JP2012002555A - Gravity center position measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gravity center position measurement device that measures a three-dimensional gravity center position of a vehicle with simple and inexpensive constitution at a fixed position.SOLUTION: The gravity center position measurement device includes a width-directional gravity center position arithmetic unit 71 which computes a width-directional gravity center position of the vehicle 3 based upon load signals from a plurality of load cells 25, 26 supporting a first mount base 11 and a plurality of load cells 27, 28 supporting a second mount base 12, a length-directional gravity center position arithmetic unit 72 which computes a length-directional gravity center position of the vehicle 3 based upon load signals from a plurality of load cells 21 to 24 supporting a third mount base 13, and a gravity center height position arithmetic unit 73 which computes a gravity center height position of the vehicle 3 based upon the load signals from the plurality of load cells 21 to 24 supporting a third mount base 13 and detection signals from vibration state amount detection means 45, 46.

Description

  The present invention relates to a center-of-gravity position measuring device that measures a three-dimensional center-of-gravity position of a vehicle.

  Vehicles such as trucks and trailers not only have a large load, but experience has shown that the position of the center of gravity of the vehicle that includes the load may deviate back and forth, left and right, and up and down depending on the form of the load, affecting the running stability of the vehicle. It has been. It has also been clarified mechanically that a rollover during turning of the vehicle or at the start of turning is caused by the three-dimensional center of gravity. Therefore, measurement of the three-dimensional center of gravity position of the vehicle is important, and there is an apparatus proposed in Patent Document 1, for example, as an apparatus that contributes to measurement of the three-dimensional center of gravity position of the vehicle.

International Publication No. 2008/062867 Pamphlet

  In the device according to Patent Document 1, the center of gravity of the vehicle in the three-dimensional space is obtained by a predetermined calculation of the calculation unit based on the detection signal from the swing detector that detects the swing of the vehicle in its own weight direction and the width direction during traveling. The position is being asked.

However, the apparatus according to Patent Document 1 has the following problems.
(1) It is necessary to input the dimensional specifications of the vehicle to the arithmetic unit, and it is troublesome to investigate the vehicle specifications and manually input the contents to the arithmetic unit, and there is a high possibility of an input error. .
(2) It is necessary to mount a rocking detector and an arithmetic unit in each vehicle, and enormous costs and time are required to spread it to all vehicles.
(3) The three-dimensional center of gravity position cannot be measured unless the vehicle travels. Therefore, traveling with the three-dimensional center-of-gravity position unknown is performed, which is not preferable from the viewpoint of safety.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a center-of-gravity position measuring apparatus that can measure the three-dimensional center of gravity of a vehicle at a fixed position with a simple and inexpensive configuration. To do.

In order to achieve the above object, the center-of-gravity position measuring apparatus according to the first invention comprises:
A center-of-gravity position measuring device that measures the three-dimensional center of gravity position of a vehicle,
(A) a first platform on which wheels on either the left or right side of the vehicle can be mounted;
(B) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the first platform;
(C) a second platform on which the left or right wheel of the vehicle can be placed;
(D) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the second platform;
(E) Width-direction center-of-gravity position calculation that calculates the center-of-gravity position in the width direction of the vehicle based on load signals from a plurality of load cells that support the first platform and a plurality of load cells that support the second platform. Means,
(F) a third platform on which all the left and right wheels of the vehicle can be mounted;
(G) a plurality of load cells arranged at predetermined intervals in the entire length direction of the vehicle and supporting the third mounting table;
(H) a full-length-direction center-of-gravity position calculating means for calculating a center-of-gravity position in the full-length direction of the vehicle based on load signals from a plurality of load cells that support the third platform;
(I) vibration generating means for freely vibrating the third platform on which the vehicle is mounted in the horizontal direction;
(J) vibration state quantity detecting means for detecting either or both of the displacement and acceleration of the third platform in a free vibration state;
(K) Center-of-gravity height position calculating means for calculating the center-of-gravity height position of the vehicle based on load signals from a plurality of load cells that support the third platform and detection signals from the vibration state quantity detecting means; It is characterized by providing.

  In the first invention, the first stage and the third stage are coupled by an elastic support or a hinge support, and the second stage and the third stage are elastically supported. It is preferred that they are joined by a body or a hinge support (second invention).

  In the first or second aspect of the invention, the vibration generating means generates an actuator that applies a horizontal force to the third platform and a restoring force with respect to a horizontal displacement of the third platform. It is possible to provide a restoring force generating mechanism (third invention).

  In the first or second aspect of the invention, the vibration generating means causes free vibration to the third stage using a force received from the vehicle that has entered the third stage when the vehicle stops. A link provided in a specific direction and a restoring force generating mechanism that generates a restoring force with respect to the horizontal displacement of the third platform can be provided (fourth invention).

Next, the center-of-gravity position measuring device according to the fifth invention is:
A center-of-gravity position measuring device that measures the three-dimensional center of gravity position of a vehicle,
(A) a first platform on which wheels on either the left or right side of the vehicle can be mounted;
(B) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the first platform;
(C) a second platform on which all the left and right wheels of the vehicle can be mounted;
(D) a plurality of load cells arranged at predetermined intervals in the width direction and the full length direction of the vehicle and supporting the second platform;
(E) Width-direction center-of-gravity position calculation that calculates the center-of-gravity position in the width direction of the vehicle based on load signals from a plurality of load cells that support the first platform and a plurality of load cells that support the second platform. Means,
(F) a full-length direction center-of-gravity position calculating means for calculating a center-of-gravity position in the full-length direction of the vehicle based on load signals from a plurality of load cells that support the second platform;
(G) vibration generating means for freely vibrating the second platform on which the vehicle is mounted in the horizontal direction;
(H) vibration state quantity detecting means for detecting either or both of the displacement and acceleration of the second platform in a free vibration state;
(I) a center-of-gravity height position calculating unit that calculates a center-of-gravity height position of the vehicle based on load signals from a plurality of load cells that support the second platform and detection signals from the vibration state quantity detecting unit; It is characterized by providing.

  5th invention WHEREIN: It is preferable that the said 1st mounting base and said 2nd mounting base are couple | bonded by the elastic support body or the hinge support body (6th invention).

  In the fifth or sixth aspect of the invention, the vibration generating means generates an actuator that applies a horizontal force to the second stage and a restoring force with respect to a horizontal displacement of the second stage. And a restoring force generating mechanism to be provided (seventh invention).

  In the fifth or sixth aspect of the invention, the vibration generating means applies free vibration to the second platform using a force received from the vehicle that has entered the second platform when the vehicle stops. A link provided in a specific direction and a restoring force generating mechanism that generates a restoring force with respect to the horizontal displacement of the second platform can be provided (eighth invention).

In the center-of-gravity position measuring apparatus according to the first aspect of the present invention, a plurality of load cells that support one platform on which one of the left and right wheels of the vehicle can be mounted and one of the left and right wheels of the vehicle can be mounted. Based on load signals from a plurality of load cells that support the second platform, the center of gravity position in the width direction of the vehicle is calculated by the width direction center of gravity position calculating means. Thereby, the gravity center position of the width direction of a vehicle can be measured.
Further, the center of gravity in the full length direction of the vehicle is calculated by the full length direction gravity center calculating means based on load signals from a plurality of load cells that support the third platform on which all the left and right wheels of the vehicle can be placed. Thereby, the center-of-gravity position in the full length direction of the vehicle can be measured.
Further, the third platform on which the vehicle is placed is brought into a free vibration state in the horizontal direction by the vibration generating means. Either or both of the displacement and acceleration of the third platform in the free vibration state are detected by the vibration state amount detection means. Then, the calculation based on the load signals from the plurality of load cells supporting the third platform and the detection signals from the vibration state quantity detection means is executed by the gravity center height position calculation means, and the center of gravity height position of the vehicle is obtained. It is done.
According to the center-of-gravity position measuring apparatus of the first invention, (1) input of dimensional specifications of the vehicle and (2) a swing detector and arithmetic unit separately mounted on the vehicle, which are required in the prior art. (3) A traveling operation or the like for measuring the center of gravity position is not required, and the three-dimensional center of gravity position can be obtained simply by mounting on the first platform, the second platform, and the third platform provided at fixed positions. Since it is measured, the three-dimensional center of gravity position of the vehicle can be measured at a fixed position with a simple and inexpensive configuration.
The term “vehicle” used in the present invention includes not only a single vehicle but also a vehicle on which a load is placed.

  By adopting the configuration of the center-of-gravity position measuring device of the second invention, the device can be made more compact than the center-of-gravity position measuring device of the first invention.

  By adopting the configurations of the third and fourth aspects of the invention, the third platform can be reliably vibrated freely in the horizontal direction with a simple configuration.

In the center-of-gravity position measuring apparatus according to the fifth aspect of the present invention, a plurality of load cells that support the first platform on which one of the left and right wheels of the vehicle can be mounted, and a second that can mount all the left and right wheels of the vehicle. Based on load signals from a plurality of load cells that support the platform, the center of gravity position in the width direction of the vehicle is calculated by the width direction center of gravity position calculating means. Thereby, the gravity center position of the width direction of a vehicle can be measured.
Further, the center of gravity position in the full length direction of the vehicle is calculated by the full length direction gravity center position calculation means based on load signals from a plurality of load cells that support the second platform on which all the left and right wheels of the vehicle can be placed. Thereby, the center-of-gravity position in the full length direction of the vehicle can be measured.
Further, the second platform on which the vehicle is placed is brought into a free vibration state in the horizontal direction by the vibration generating means. Either one or both of the displacement and acceleration of the second stage in the free vibration state is detected by the vibration state amount detection means. Then, the calculation based on the load signals from the plurality of load cells supporting the second platform and the detection signals from the vibration state quantity detection means is executed by the gravity center height position calculation means, and the center of gravity height position of the vehicle is obtained. It is done.
Also according to the center of gravity position measuring apparatus of the fifth aspect of the invention, (1) input of the dimensional specifications of the vehicle, (2) a swing detector or arithmetic unit separately mounted on the vehicle, (3) A traveling operation or the like for measuring the center of gravity position is not required, and the three-dimensional center of gravity position is measured simply by being placed on the first platform and the second platform provided at fixed positions. The three-dimensional center of gravity position of the vehicle can be measured at a fixed position with an inexpensive configuration.

  By adopting the configuration of the center-of-gravity position measuring apparatus of the sixth invention, the apparatus can be made more compact than the center-of-gravity position measuring apparatus of the fifth invention.

  By adopting the configurations of the seventh invention and the eighth invention, the second stage can be surely freely vibrated in the horizontal direction with a simple configuration.

BRIEF DESCRIPTION OF THE DRAWINGS It is structure explanatory drawing of the gravity center position measuring apparatus which concerns on the 1st Embodiment of this invention, AA sectional view taken on the line (a) of (a), (b), BB sectional drawing of (b) C part enlarged view of (c) and (b) (d) Fig.1 (a) DD sectional view Explanatory drawing of the support structure of the platform Theoretical illustration of the generation of restoring force Schematic system configuration diagram of a control system of the center-of-gravity position measuring apparatus according to the first embodiment Microprocessor functional block diagram Definition diagram of coordinate system for horizontal center of gravity of vehicle The figure showing the state of load change when the vehicle is placed on the third platform, and showing the relationship between the position x of the first axle and P ₁₃ (x) and P ₁₃ (t) State diagram (a) of loads acting on the first and second platforms when the vehicle is placed on the first platform and a skeleton (b) showing the resultant action point position for each axle The flowchart explaining the measurement operation | movement of the horizontal surface gravity center position by the gravity center position measuring apparatus of 1st Embodiment. FIG. 2 is a theoretical explanatory view (1) of how to obtain the height of the center of gravity, and is a plan view (a) and a cross-sectional view taken along the line E-E of (a) showing a model of a state where the vehicle is mounted on a third platform. Fig. 11 (a) is a cross-sectional view taken along line FF in Fig. 11 (a), which is a theoretical illustration (2) of how to obtain the center of gravity The flowchart explaining the measurement operation | movement of the gravity center height position by the gravity center position measuring apparatus of 1st Embodiment. Time chart for explaining the measurement operation of the center of gravity height position by the center of gravity position measuring apparatus of the first embodiment It is structure explanatory drawing of the gravity center position measuring apparatus which concerns on the 2nd Embodiment of this invention, GG sectional drawing (b) of a top view (a) and (a), HH sectional drawing of (a) Sectional view taken along line II of (c) and (b) (d) A state diagram (a) of a load acting on the left and right wheels of the first axle of the vehicle on the first platform and the second platform, respectively, and a plan view showing the center of gravity position of the vehicle ( b) The flowchart explaining the measurement operation | movement of the horizontal plane gravity center position by the gravity center position measuring apparatus of 2nd Embodiment. It is structure explanatory drawing of the gravity center position measuring apparatus which concerns on the 3rd Embodiment of this invention, JJ sectional view (b) of a top view (a) and (a), KK sectional drawing of (b) (C) Enlarged view of L part of (c) and (b) State diagram of load acting when vehicle is placed on second platform (a) and graph (b) showing load change The flowchart explaining the measurement operation | movement of the horizontal plane gravity center position by the gravity center position measuring apparatus of 3rd Embodiment. It is structure explanatory drawing of the gravity center position measuring apparatus which concerns on the 4th Embodiment of this invention, MM sectional view taken on the plane (a) and (a), (b), NN sectional drawing of (a) OO line sectional view of (c) and (b) (d) Explanatory drawing of another example of load vertical transmission mechanism Structure explanatory diagram of hinge support Structural explanatory diagram of the main part of other means for giving the initial condition of free vibration to the mounting table (a) and theoretical explanatory diagram of displacement restraint of the mounting table (b) Flowchart for explaining the measurement operation of the center of gravity height position by the center of gravity position measuring apparatus of the first embodiment when the initial condition of free vibration is given to the platform by the link mechanism Time chart for explaining the measurement operation of the center-of-gravity height position by the center-of-gravity position measurement device of the first embodiment when the initial condition of free vibration is given to the mounting base by the link mechanism It is explanatory drawing (1) of the other example of a mounting base support structure, PP sectional view (b) of front view (a) and (a), and Q section enlarged view (c) of (a) It is explanatory drawing (2) of the other example of a mounting support structure, RR sectional view (b) of front view (a) and (a), and the S section enlarged view (c) of (a) It is explanatory drawing (3) of the other example of a mounting base support structure, TT sectional view taken on the line of the front view (a) and (a) (b)

  Next, specific embodiments of the center-of-gravity position measuring apparatus according to the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a structural explanatory view of the center-of-gravity position measuring apparatus according to the first embodiment of the present invention, and is a cross-sectional view taken along the line A-A in FIGS. The C section enlarged view (d) of -B sectional view (c) and (b) is each shown.

<Description of Schematic Configuration of Center of Gravity Position Measuring Device According to First Embodiment>
The center-of-gravity position measuring apparatus 1 shown in FIG. 1 includes a first platform 11, a second platform 12, and a third platform 13.
The first platform 11 and the second platform 12 are arranged on the upstream side of the travel route when the vehicle 3 such as a truck or a trailer travels forward on the installation base 2.
The third platform 13 is arranged on the downstream side of the forward travel path of the vehicle 3 with respect to the first platform 11 and the second platform 12 on the installation base 2.
In the present embodiment, the vehicle 3 has one axle 7, 8, 9 with wheels 4 a, 5 a, 6 a; 4 b, 5 b, 6 b mounted on the left and right respectively, below the driver's seat and below the loading platform. This is a three-axis vehicle having two, three in total (see FIG. 7).
In the following description, the front-rear and left-right directions are determined based on the forward direction of the vehicle 3.

<Overview of the first to third platforms>
The first platform 11 is composed of a rectangular plate-like member on which the left wheels 4 a, 5 a, 6 a of the axles 7, 8, 9 of the vehicle 3 can be placed one by one.
The second platform 12 is formed of a rectangular plate-like member on which the right wheels 4b, 5b, 6b of the axles 7, 8, 9 of the vehicle 3 can be placed one by one.
The third platform 13 is formed of a rectangular plate-like member on which all the left and right wheels 4a, 5a, 6a; 4b, 5b, 6b of the vehicle 3 can be placed simultaneously.

<Description of Arrangement of First Load Cell to Fourth Load Cell>
A first load cell 21, a second load cell 22, a third load cell 23, and a fourth load cell 24 are interposed between the installation base 2 and the third mounting base 13, respectively.
The first load cell 21 is disposed so that the left corner of the third platform 13 on the upstream side of the vehicle forward travel path can be supported from below.
The second load cell 22 is disposed so that the left corner of the third platform 13 on the downstream side of the vehicle forward travel path can be supported from below.
The third load cell 23 is arranged so that the right corner of the third platform 13 on the upstream side of the vehicle forward travel path can be supported from below.
The fourth load cell 24 is arranged so that the right corner of the third platform 13 on the downstream side of the vehicle forward travel path can be supported from below.

<Description of basic structure of first load cell to fourth load cell>
As shown in FIG. 3, the first load cell 21 to the fourth load cell 24 are column type load cells using a double convex loading type strain gauge, and include an elastic body 31 and a sealed casing 32.
The elastic body 31 is made of, for example, a metal such as an aluminum alloy or stainless steel and is formed in a substantially cylindrical shape, and is arranged upright with its axis line directed in the vertical direction.
The elastic body 31 has a strain generating portion 33 formed at the central portion in the axial direction, an upper convex surface 34 formed at the upper end, and a lower convex surface 35 formed at the lower end. Each of the upper convex surface 34 and the lower convex surface 35 is formed in a partial spherical shape having a predetermined radius of curvature R.
The elastic body 31 is incorporated in the sealed casing 32 in a state where the strain generating portion 33 is hermetically housed in the sealed casing 32 and the upper end portion and the lower end portion are exposed from the sealed casing 32.
A required strain gauge (not shown) attached to the strain generating portion 33 converts the load applied to the elastic body 31 into an electrical load signal according to the magnitude and outputs the electrical load signal.

<Description of the upper receiving member and the lower receiving member of the first load cell to the fourth load cell>
An upper receiving member 36 is interposed between the upper end portion of the elastic body 31 and the third mounting table 13. The upper receiving member 36 has a horizontal seating surface 37, and is fixed to the third platform 13 in a state where the horizontal seating surface 37 is in contact with the upper convex surface 34 of the elastic body 31.
A lower receiving member 38 is interposed between the lower end portion of the elastic body 31 and the installation base 2. The lower receiving member 38 has a horizontal seating surface 39, and is fixed to the installation base 2 in a state where the horizontal seating surface 39 is in contact with the lower convex surface 35 of the elastic body 31.

<Description of basic configuration of restoring force generation mechanism>
The restoring force generating mechanism includes an upper convex surface 34 of the elastic body 31 and a horizontal seating surface 37 of the upper receiving member 36, and a lower convex surface 35 of the elastic body 31 and a horizontal seating surface 39 of the lower receiving member 38. . The restoring force generating mechanism generates a restoring force F with respect to the horizontal displacement y ₀ of the third platform 13. This restoring force F will be described below with reference to FIG.

<Theoretical explanation of the generation of restoring force>
In FIG. 4, the elastic body 31 of the first load cell 21 to the fourth load cell 24 moves from the vertical state by y _{0 in the} horizontal direction and tilts by θ with the horizontal displacement y ₀ of the third platform 13. The state is shown. Symbols in the figure are defined as follows.
y ₀ : Amount of movement of the upper part of the elastic body 31 S: Length of contact point between the upper and lower parts of the elastic body 31 H: Height of the elastic body 31 (height of the load cells 21 to 24)
A: radius of curvature of upper convex surface 34 (= R)
B: radius of curvature of lower convex surface 35 (= R)
N: Vertical load acting on the elastic body 31 θ: Inclination angle of the elastic body 31 Of the symbols, H, A, and B are known values, and these values are stored in a memory 68 described later.

<Theoretical explanation of the generation of restoring force>
In FIG. 4, if the value of the inclination angle θ of the elastic body 31 is very small, the following equation (1) is established.
tan θ≈y ₀ / H (1)

Further, the contact point length S between the upper and lower portions of the elastic body 31 can be expressed by the following equation (2).
S≈A · tan θ + (B−H) tan θ
= (A + B−H) · y ₀ / H (2)

The ratio K between the vertical load N and the restoring force F can be expressed by the following equation (3).
K = F / N≈S / H = (A + B−H) · y ₀ / H ² (3)

From the equation (3), the restoring force F can be expressed by the following equation (4).
F = N · (A + B−H) · y ₀ / H ² (4)

<Description of actuator giving initial conditions for free vibration>
As shown in FIG. 2, a hydraulic cylinder 40 is disposed in the vicinity of the side on which the third load cell 23 and the fourth load cell 24 are installed in the third platform 13. The hydraulic cylinder 40 pushes the side surface of the third mounting table 13 with the piston rod 40a during the extension operation, and applies a horizontal force to the third mounting table 13, whereby the horizontal pressure is applied to the third mounting table 13. Displacement and speed can be given. The hydraulic cylinder 40 functions as an actuator that gives an initial condition of free vibration to the third platform 13. In place of the hydraulic cylinder 40, for example, a pneumatic cylinder or a magnetic fluid cylinder may be used.
Here, the “initial condition” is a concept including “initial displacement” and “initial velocity”, and is a collective term for these.

<Description of hydraulic circuit of hydraulic cylinder>
The hydraulic cylinder 40 is connected to a hydraulic pump 42 via an electromagnetic valve 41. When the hydraulic pump 42 is driven by the operation of the electric motor 43, the pressure oil from the hydraulic pump 42 is supplied to the head side oil chamber or the bottom side oil chamber of the hydraulic cylinder 40 according to the switching operation of the electromagnetic valve 41. It has become.

<Description of hydraulic cylinder operation>
When a solenoid valve control signal indicating an extension command for the hydraulic cylinder 40 is transmitted from the control device 60 described later to the solenoid valve 41, the solenoid valve 41 performs the following oil path switching operation in accordance with the solenoid valve control signal. To do. That is, the solenoid valve 41 supplies the pressure oil from the hydraulic pump 42 to the bottom side oil chamber of the hydraulic cylinder 40, and at the same time, returns the oil inside the head side oil chamber of the hydraulic cylinder 40 to the tank 44. Switch. As a result, the hydraulic cylinder 40 is extended, and the side surface of the third platform 13 is pushed by the piston rod 40a, so that the horizontal displacement and speed are given to the third platform 13.
On the other hand, when a solenoid valve control signal indicating a contraction command for the hydraulic cylinder 40 is transmitted to the solenoid valve 41 from a control device 60 described later, the solenoid valve 41 responds to the solenoid valve control signal as follows. Perform the switching operation. That is, the solenoid valve 41 supplies the pressure oil from the hydraulic pump 42 to the head side oil chamber of the hydraulic cylinder 40 and at the same time returns the oil in the bottom side oil chamber of the hydraulic cylinder 40 to the tank 44. Switch. As a result, the hydraulic cylinder 40 is contracted and the contact between the third platform 13 and the piston rod 40a is released.

<Description of the free vibration of the third platform>
In order to freely vibrate the third platform 13 in the horizontal direction (y direction), first, initial conditions (initial displacement and initial speed) are given to the third platform 13 by the expansion / contraction operation of the hydraulic cylinder 40. A restoring force F from a restoring force generating mechanism with respect to a displacement in the horizontal direction acts on the third platform 13. In this way, by applying the restoring force F to the horizontal displacement of the third platform 13, the third platform 13 can be freely vibrated in the horizontal direction.

<Description of displacement sensor>
A displacement sensor 45 is arranged in the vicinity of the side on which the first load cell 21 and the second load cell 22 are installed in the third platform 13 so as to face the hydraulic cylinder 40. The displacement sensor 45 functions as a displacement detection unit that detects the displacement of the third stage 13 in a free vibration state. As the displacement sensor 45, various types of sensors can be adopted, and examples thereof include an optical displacement sensor, an eddy current displacement sensor, and a differential transformation displacement sensor.

<Description of acceleration sensor>
An acceleration sensor 46 is disposed in the vicinity of the side on which the first load cell 21 and the second load cell 22 are installed in the third platform 13 so as to face the hydraulic cylinder 40. The acceleration sensor 46 functions as an acceleration detection unit that detects the acceleration of the third platform 13 in a free vibration state. As the acceleration sensor 46, various types of sensors can be employed, such as a capacitance type acceleration sensor, a metal strain gauge type acceleration sensor, a semiconductor strain gauge type acceleration sensor, and a piezoelectric acceleration sensor. It is done.

<Explanation of arrangement of fifth and sixth load cells>
As shown in FIG. 1, a fifth load cell 25 and a sixth load cell 26 are interposed between the installation base 2 and the first platform 11, respectively.
The fifth load cell 25 is disposed so as to support the left side portion of the first mounting base 11 from below.
The sixth load cell 26 is disposed so as to support the right side portion of the first mounting base 11 from below.

<Arrangement description of seventh load cell and eighth load cell>
A seventh load cell 27 and an eighth load cell 28 are interposed between the installation base 2 and the second mounting table 12, respectively.
The seventh load cell 27 is disposed so as to support the left side portion of the second mounting table 12 from below.
The eighth load cell 28 is arranged so that the right side of the second mounting table 12 can be supported from below.

<Functional description of the fifth to eighth load cells>
The fifth load cell 25 to the eighth load cell 28 are strain gauge column type load cells having a general structure in which the restoring force generation mechanism provided in the first load cell 21 to the fourth load cell 24 is not particularly provided. Accordingly, it has a function of converting it into an electrical load signal and outputting it.

<Description of load vertical transmission mechanism>
A required load vertical transmission mechanism 50 is further interposed between the installation base 2 and the second platform 12. The load vertical transmission mechanism 50 includes a leg portion 51 fixed to the installation base 2, a parallelogram-shaped link portion 52, and a platform support portion 53 that supports the second platform 12. The Roverval mechanism 52 eliminates the influence of the eccentric load in the front-rear direction of the second platform 12 and is integrally formed of a metal elastic body. By providing this load vertical transmission mechanism 50 between the installation base 2 and the second platform 12, the seventh load cell 27 and the right load wheels 4b, 5b, 6b of the vehicle 3 through the second platform 12 and The load acting on the eighth load cell 28 can be transmitted only in the vertical direction.
The load vertical transmission mechanism 50 is also interposed between the installation base 2 and the first platform 11 in the same manner, and the first platform 11 is moved from the left wheels 4a, 5a, 6a of the vehicle 3. Thus, the load acting on the fifth load cell 25 and the sixth load cell 26 can be transmitted only in the vertical direction.

<Description of System Configuration of Control System of Center of Gravity Position Measuring Device of First Embodiment>
As shown in FIG. 5, the center-of-gravity position measurement apparatus 1 according to the first embodiment includes a control device 60, an operation device 61, and a display device 62.

<Overview of control device>
The control device 60 mainly includes an amplifier 63, a low-pass filter 64, a multiplexer 65, an A / D converter 66, an I / O circuit 67, a memory 68, and a microprocessor (MPU) 69. Yes.
The amplifier 63 has a function of amplifying and sending out a signal to be sent to a size that allows A / D conversion.
The low-pass filter 64 has a function of allowing only a low frequency to pass as a signal.
The multiplexer 65 has a function of selectively sending out a plurality of signals to be sent based on a command of the selection control signal.
The A / D converter 66 has a function of converting an analog signal from the multiplexer 65 into a digital signal.
The I / O circuit 67 has a function of exchanging various signals and data among the solenoid valve 41, the operation device 61, the display device 62, the multiplexer 65, the A / D converter 66, and the MPU 69. Have.
The memory 68 includes a PROM, a RAM, and the like, and has a function of storing a predetermined program, basic data, and the like for a long time, and temporarily storing various data, numerical values for calculation, and the like.
The MPU 69 receives necessary signals via the I / O circuit 67 in accordance with instructions of a predetermined program stored in the memory 68, receives necessary data from the memory 68, and performs an operation based on the received signals and data. Has the function to execute.

<Overview of operating device>
The operation device 61 includes operation switches and numerical keys, and is used in various operations such as measurement start / end operations, zero point adjustment operations, use mode switching operations, and numerical value setting operations.

<Overview of display device>
The display device 62 is composed of, for example, a liquid crystal display, and displays measurement results and various data input / output screens.

<Schematic Explanation of Processing Operation of Control System of Center of Gravity Position Measuring Device of First Embodiment>
In the control system of the center-of-gravity position measuring apparatus 1, the signals output from the load cells 21 to 28, the displacement sensor 45, and the acceleration sensor 46 are supplied to an amplifier 63, a low-pass filter 64, a multiplexer 65, and an A / D converter 66. And sent to the MPU 69 via the I / O circuit 67. The MPU 69 takes in a signal from the I / O circuit 67 according to a predetermined program stored in the memory 68, reads various data stored in the memory 68, and determines the vehicle 3 based on these signals and data. Performs calculation of the 3D center of gravity position. The calculation result is displayed on the display device 62.

<Functional explanation of MPU>
In the MPU 69, by executing a predetermined program, as shown in FIG. 6, a width direction gravity center position calculation unit 71, a full length direction gravity center position calculation unit 72, a gravity center height position calculation unit 73, and a solenoid valve control signal generation The functions of the unit 74 and the display signal generation unit 75 are realized. In the following, when the width-direction center-of-gravity position calculation unit 71 and the full-length-direction center-of-gravity position calculation unit 72 are collectively expressed, they are referred to as “horizontal center-of-gravity position calculation unit 70”.

<Theoretical explanation of how to obtain the coordinates (X _G , Y _G ) of the horizontal center of gravity position of the center of gravity G of the vehicle>
Next, how to obtain the coordinates (X _G , Y _G ) of the horizontal center of gravity position of the center of gravity G of the vehicle 3 will be described mainly with reference to FIGS.
In FIG. 7, the X axis is defined along the vehicle center line that passes through the center position in the width direction of the vehicle 3 and extends in the full length direction, the Y axis is defined along the first axle 7, and the first axle 7 of the vehicle 3 and the vehicle An orthogonal coordinate system O-XY is defined by taking the origin at the intersection with the center line.
The x-axis is defined along a center line extending in the full length direction through the center position in the width direction of the third platform 13, and along the center line extending in the width direction through the center position in the length direction of the third platform 13 Then, the y axis is determined, the origin is set at the center of the third stage 13, and the orthogonal coordinate system o-xy is determined.
Assume that the output of each of the load cells 21 to 24 is adjusted to zero when there is no load.

<Explanation of symbol definitions (vehicle-related)>
The meanings of symbols used in FIGS. 7 to 9 and in the theoretical formula are defined as follows.
G: Center of gravity of the vehicle 3 G _i : Resulting point of resultant force of both wheels of the i-th axle of the vehicle 3 i (= 1, 2,..., K): Axle number k: Number of axles X _G : Coordinate system O− center of gravity of the entire length direction of the vehicle 3 in the XY Y _G: gravity center position in the width direction of the vehicle 3 in the coordinate system O-XY x _G: gravity center position of the total length direction of the vehicle 3 in the coordinate system o-xy y _G: coordinate system o The center-of-gravity position in the width direction of the vehicle 3 at -xy B _i : Effective tread width The “tread width” here is the distance between the centers of the left and right wheels (wheel distance).
l _j : Distance between axles j (= 1, 2,..., k−1): Number between axles (k ≧ 2)
CL _T: center line showing the center position in the width direction of the tread width GL _i: vertical line e _i through the resultant force acting point _{G i:} distance between the center line CL _T and the vertical line GL _i

<Explanation of symbol definitions (related to load cells)>
LC1: first load cell 21
LC2: second load cell 22
LC3: Third load cell 23
LC4: Fourth load cell 24
LC5: Fifth load cell 25
LC6: Sixth load cell 26
LC7: Seventh load cell 27
LC8: Eighth load cell 28
a: Center-to-center distance between the first load cell 21 (third load cell 23) and the second load cell 22 (fourth load cell 24) b: First load cell 21 (second load cell 22) and third load cell 23 (fourth load cell 24) B _i : Distance between the center point of the fifth load cell 25 and the operating point of the left wheel load of the i-th axle b _i ': The distance between the center point of the eighth load cell 28 and the right wheel load of the i-th axle Distance to working point C _i : Distance between the center point of the fifth load cell 25 and the vertical line GL _{i 10} : Distance between the centers of the second load cell 22 (fourth load cell 24) and the first axle Of these, a and b are known values, and these values are stored in the memory 68 in advance.

<Explanation of symbol definitions (table-related)>
CL _S: first the platform 11 and the center line b ₀ indicating an intermediate position between the second load platform 12: the width dimension of the first mounting base 11 (second load platform 12) L: third mounting of Dimensions in the full length direction of the table 13 Of the symbols, b ₀ and L are known values, and these values are stored in the memory 68 in advance.

<Description of symbol definition (relative position relation between vehicle and platform)>
f: distance between the X-axis and the x-axis (distance between the center line CL _T and the center line CL _S)

<Explanation of symbol definitions (mechanics)>
W _Li : Wheel load (left side)
W _Ri : Wheel load (right side)
W _i : Axial weight of the i-th axis W: Gross weight P _i : Force acting on the i-th load cell (static load) [= Force acting on the platform from the load cell (static load)]
P _j : force acting on the jth load cell (static load) [= force acting on the platform from the load cell (static load)]
P _ij : P _i + P _j
P = P ₁ + P ₂ + P ₃ + P ₄
^Pi : Effect of the i-th axle on P

<Description of Measurement of X _G , l _j : See FIG. 8>
FIG. 8 is a diagram showing how the load changes when the vehicle is placed on the third platform, and a diagram showing the relationship between the position x of the first axle and P ₁₃ (x) and P ₁₃ (t). It is shown.
For the measurement of X _G, it is essential to measure the _{l j.} Further, l _j can be obtained from the waveforms of the outputs P ₁ (t) to P ₄ (t) of the first load cell 21 to the fourth load cell 24.

<Description of how to obtain l ₁ and l ₂ >
The time when the peak first occurs in the P ₁₃ (t) waveform is taken as the time origin (t = 0), and the time when the extreme value occurs after that is defined as t ₁ , t ₂ , and t ₃ .
Let r be the distance between the position x of the first axle 7 corresponding to P ₁₃ (0) and the vehicle forward travel path upstream end of the third platform 13. This r is equivalent to half the tire ground contact length. Further, s is the distance between the position x of the first axle 7 corresponding to P ₁₃ (0) and the center point of the first load cell 21 (third load cell 23).
For the distance s, the following equation (11) is established.
P ¹ (0) / (a + s) = W ₁ / a (11)
Here, W ₁ = P ¹ (t), 0 <t <t ₁ .

S can be obtained from the above equation (11) as shown by the following equation (12).
s = {P ¹ (0) / W ₁ −1} a (12)

On the other hand, the following equation (13) is established for the distance r and the distance s.
r + s = L / 2−a / 2 (13)

From the equation (13), r can be obtained as shown by the following equation (14).
r = L / 2−a / 2−s (14)

<Determination of the explanation _{l 1>}
With respect to the distance l ₁ between the first axle 7 and the second axle 8, a relational expression represented by the following expression (15) is established.
P ¹ (0) / (a + s) = P ¹ (t ₁ ) / (a + s−l ₁ + r) (15)

From the above formula (15), l ₁ can be obtained as shown in the following formula (16).
l ₁ = (a + s) {1−P ¹ (t ₁ ) / P ¹ (0)} + r (16)

<Determination of description _{l 2>}
In obtaining the distance l ₂ between the second axle 8 and the third axle 9, first, P ¹ (t ₂ ) and P ² (t ₂ ) are obtained.

For P ¹ (t ₂ ), the relational expression expressed by the following expression (17) is established.
P ¹ (0) / (a + s) = P ¹ (t ₂ ) / (a + s−1 ₁ ) (17)

From the equation (17), P ¹ (t ₂ ) can be obtained as shown by the following equation (18).
P ¹ (t ₂ ) = {(a + s−l ₁ ) / (a + s)} P ¹ (0) (18)

^Further, P 2 _{(t 2)} can be obtained from the following equation (19).
P ² (t ₂ ) = P ₁₃ (t ₂ ) −P ¹ (t ₂ ) (19)

<Determination of description _{l 2>}
Next, P ¹ (t ₃ ) and P ² (t ₃ ) are represented by P ¹ (t ₂ ), P ² (t ₂ ), and l ₂ .

The following equation (20) is established for P ¹ (t ₃ ).
P ¹ (t ₂ ) −P ¹ (t ₃ ) = {(l ₂ −r) / (a + s)} P ¹ (0)
... (20)

From the equation (20), P ¹ (t ₃ ) can be obtained as shown in the following equation (21).
P ¹ (t ₃ ) = P ¹ (t ₂ ) − {(l ₂ −r) / (a + s)} P ¹ (0)
... (21)

Further, the following equation (22) is established for P ² (t ₃ ).
^{_{P 2 (t 2) -P 2}} (t 3) = {(l 2 -r) / (a + s)} P 2 (t 2)
(22)

From the equation (22), P ² (t ₃ ) can be obtained as shown in the following equation (23).
^{_{P 2 (t 3) = P}} 2 (t 2) - {(l 2 -r) / (a + s)} P 2 (t 2)
(23)

<Determination of description _{l 2>}
P ₁₃ (t ₃ ) can be expressed by the following equation (24).
P ₁₃ (t ₃ ) = P ¹ (t ₃ ) + P ² (t ₃ ) (24)

The equations (21) and (23) are substituted into the equation (24), respectively.
P ₁₃ (t ₃ ) = P ¹ (t ₂ ) − {(l ₂ −r) / (a + s)} P ¹ (0)
+ P ² (t ₂ ) − {(l ₂ −r) / (a + s)} P ² (t ₂ )
... (25)

The equation (25) can be modified as shown in the following equation (26).
{(L ₂ −r) / (a + s)} · (P ¹ (0) + P ² (t ₂ )) =
P ¹ (t ₂ ) + P ² (t ₂ ) −P ₁₃ (t ₃ ) (26)

From the equation (26), l ₂ can be obtained as shown by the following equation (27).
l ₂ = (a + s) [{(P ¹ (t ₂ ) + P ² (t ₂ ) −P ₁₃ (t ₃ )} / {(P ¹ (0) + P ² (t ₂ )}] + r. 27)

<Determination of the description of _{X G>}
As apparent from FIG. 7 (a), the center-of-gravity position X _G in the overall length direction of the vehicle 3 can be expressed by the following equation (28).
X _G = − {(a / 2−l ₀ ) −x _G } (28)

From the balance of moments when all the wheels 4a, 5a, 6a; 4b, 5b, 6b are placed on the third platform 13 (t ₄ <t <t ₅ : see FIG. 29) holds.
W ₁ l ₀ + W ₂ (l ₀ + l ₁ ) + W ₃ (l ₀ + l ₁ + l ₂ ) −P ₁₃ a = 0
... (29)

From the above equation (29), l ₀ can be obtained as shown in the following equation (30).
l ₀ = {P ₁₃ a−W ₂ l ₁ −W ₃ (l ₁ + l ₂ )} / W (30)

Here, W in the formula (30) is represented by the following formula (31).

前記式（３２）からｘ_Ｇは次式（３４）で示されるように求めることができる。
ｘ_Ｇ＝ａ（Ｐ_２４／Ｐ−１／２） ・・・（３４）

前記式（２８）（３０）（３４）から車両３の全長方向の重心位置Ｘ_Ｇを求めることができる。 <Determination of the description of _{X G>}
Similarly, the following equation (32) is established from the moment balance of the vehicle 3 at time t (t ₄ <t <t ₅ ).
_{(A / 2 + x G)} P = aP 24 ··· (32)

Here, P in the formula (32) is represented by the following formula (33).

Wherein _{x G} from formula (32) can be obtained as shown in the following equation (34).
x _G = a (P ₂₄ / P−1 / 2) (34)

Formula (28) (30) (34) to be able to determine the center of gravity position _{X G} in the overall length direction of the vehicle 3.

<Description of measurement of Y _G and B _i : see FIG. 9>
FIG. 9 shows a state diagram (a) of a load acting on the platforms when the vehicle is placed on the first platform and the second platform, and a skeleton (b) showing the resultant action point position for each axle. Are shown respectively.
To measure the Y _{G, B i} and _{b i, b} i 'measurement is essential.

<Description of how to obtain Y _G and B _i >
As is clear from FIGS. 9A and 9B, the following expression (35) is established with respect to the center of gravity position Y _{G in} the width direction of the vehicle 3.
(W ₁ + W ₂ + W ₃ ) Y _G = W ₁ e ₁ + W ₂ e ₂ + W ₃ e ₃ (35)

From the above equation (35), Y _G can be expressed as the following equation (36).
Y _G = (W ₁ e ₁ + W ₂ e ₂ + W ₃ e ₃ ) / (W ₁ + W ₂ + W ₃ ) (36)

C _i from the equation the moment balance in the state shown in FIG. 9 (a) can be expressed by the following equation (37).
C _i = {b _i W _Li + (b _i + B _i ) W _{R i} } / W _i
= B _i + W _Ri B _i / W _i (37)

Here, W _Ri can be obtained from the following equation (38).
W _Ri = P ⁱ ₇₈ (38)

<Description of how to obtain Y _G and B _i >
E _i As is clear from FIG. 9 (a) can be expressed by the following equation (39).
e _i = b _i + B _i / 2−C _i (39)

When the equation (37) is substituted into the equation (39), e _i can be expressed as the following equation (40).
e _i = b _i + B _i / 2−b _i + W _Ri B _i / W _i
= B _i / 2-W _Ri B _i / W _i
= (1 / 2-W _Ri / W _i ) B _i (40)

図９（ａ）から明らかなようにＢ_ｉは次式（４２）のように表わすことができる。
Ｂ_ｉ＝ｂ−（ｂ_ｉ＋ｂ_ｉ´） ・・・（４２）

ｂ_ｉは、第５ロードセル２５および第６ロードセル２６に作用する荷重の比から次式（４３）から求めることができる。
ｂ_ｉ＝（Ｐ_６／Ｐ_５６）ｂ_０ ・・・（４３）

同様にして、ｂ_ｉ´は第７ロードセル２７および第８ロードセル２８に作用する荷重の比から次式（４４）から求めることができる。
ｂ_ｉ´＝（Ｐ_７／Ｐ_７８）ｂ_０ ・・・（４４）

前記式（４１）（４２）（４３）（４４）から車両３の幅方向の重心位置Ｙ_Ｇを求めることができる。 <Description of how to obtain Y _G and B _i >
Y _G can be expressed by the following equations (41) from the equations (36) and (40).

As is clear from FIG. 9A, B _i can be expressed by the following equation (42).
B _i = b− (b _i + b _i ′) (42)

b _i can be obtained from the following equation (43) from the ratio of the loads acting on the fifth load cell 25 and the sixth load cell 26.
b _i = (P ₆ / P ₅₆ ) b ₀ (43)

Similarly, b _i ′ can be obtained from the following formula (44) from the ratio of loads acting on the seventh load cell 27 and the eighth load cell 28.
b _i ′ = (P ₇ / P ₇₈ ) b ₀ (44)

The center-of-gravity position Y _G in the width direction of the vehicle 3 can be obtained from the equations (41), (42), (43), and (44).

<Description of Measuring Operation of Horizontal Center of Gravity Position of Center of Gravity Position Measurement Device of First Embodiment>
Next, the horizontal barycentric position measurement operation of the center-of-gravity position measuring apparatus 1 will be described below mainly using the functional block diagram of FIG. 6 and the flowchart of FIG. In FIG. 10, symbols “S” and “T” represent steps.

<Description of Processing Contents of Step S1 to Step S3>
The width direction center-of-gravity position calculation unit 71 reads the load signals of the fifth load cell 25 to the eighth load cell 28, and based on the read load signals and the equations (42), (43), and (44), the effective tread width B _i is calculated, and the center-of-gravity position Y _G in the width direction of the vehicle 3 in the coordinate system O-XY is calculated based on the obtained value of the effective tread width B _i and the equation (41) (S1). .
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the width direction gravity center position calculation unit 71 (S2). Thereby, the value of the barycentric position in the width direction of the vehicle 3 is displayed on the display device 62 (S3).

<Description of Processing Contents of Step T1 to Step T3>
The full-length direction center-of-gravity position calculation unit 72 reads the load signals of the first load cell 21 to the fourth load cell 24, and based on the read load signals and the equations (16) and (27), the inter-axle distances l ₁ , l ₂ and the center of gravity of the vehicle 3 in the full length direction in the coordinate system O-XY based on the calculated values of the inter-axle distances l ₁ and l ₂ and the expressions (28), (30), and (34). The position _XG is calculated (T1).
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the full length direction gravity center position calculation unit 72 (T2). Thereby, the value of the barycentric position in the full length direction of the vehicle 3 is displayed on the display device 62 (T3).

<Theoretical explanation of how to find the center of gravity height h of the vehicle>
Next, how to obtain the center of gravity height h of the vehicle 3 will be described below mainly using FIG. 11 and FIG. In the following theoretical explanation, it is assumed that the third platform 13 on which the vehicle 3 is placed is in a free vibration state. The hydraulic cylinder 40 gives an initial condition of free vibration, and the restoring force F from the restoring force generating mechanism is applied, so that the third platform 13 on which the vehicle 3 is placed can be freely moved in the horizontal direction (y direction). Vibrate. In FIG. 12, the y coordinate y _G of the center of gravity G of the vehicle 3 at rest is represented by d. The 0-yz coordinate system is a coordinate system fixed in space. In order to simplify the explanation of the theory, it is assumed that the third platform 13 is a rectangular parallelepiped having a constant density. The origin of the coordinate systems 0 to xyz is set at the center of the third platform 13. Assume that the output of each of the load cells 21 to 24 is adjusted to zero when there is no load.

  Here, a new symbol used in the following description is defined.

(Sentence 1)

Of the symbols, m ₀ , c, and e are known values, and these values are stored in the memory 68 in advance.

If the vehicle 3 is rigid, the relative displacement in the Z-direction between the center of gravity G ₀ of the center of gravity G and the third load platform 13 of the vehicle 3 is zero. When the vehicle 3 is a non-rigid body, the relative displacement is not zero, but the amount is very small. Therefore, the amount of the relative displacement is ignored in the following equation of motion. That is, Z ₀ (t) = Z _G (t) is set. At this time, the equation of motion of the system is expressed by the following equations (49) and (50).

The expressions (49) and (50) are established regardless of whether or not the vehicle 3 is a rigid body.
Further, the following equation (51) is obtained as a balance condition for the overturning moment.

ここに、δは、重心Ｇの重心Ｇ_０に対するｙ方向の相対変位である。δは（ｂ／２−ｄ）に比較して微小であるから以下の式変形においては無視する。

Here, [delta] is the relative displacement in the y direction relative to the center of gravity G ₀ of the center of gravity G. Since δ is very small compared to (b / 2−d), it is ignored in the following equation modification.

(Sentence 2)

前記式（５２）より、車両３の重心高さｈを求める次式（５３）が得られる。

From the equation (52), the following equation (53) for obtaining the center-of-gravity height h of the vehicle 3 is obtained.

  In Equation (4) for obtaining the restoring force F described above, the vertical load N acting on the elastic body 31 is Mg (g: gravitational acceleration), and the radii of curvature A and B of the upper convex surface 34 and the lower convex surface 35 of the elastic body 31 are Since both have the predetermined radius R, the restoring force F of the third platform 13 supported by the load cells 21 to 24 can be expressed by the following equation (54).

前記式（５４）を前記式（５３）に代入してｈを書き直すと次式（５５）となる。

Substituting the equation (54) into the equation (53) to rewrite h, the following equation (55) is obtained.

ただし、ｋは次式（５６）で表わされるものである。

However, k is represented by the following equation (56).

(Sentence 3)

(Sentence 4)

  Here, the term “rigid body” refers to a “perfect rigid body” in which deformation due to external force does not occur at all. It includes “deemed rigid bodies” that have no problem. The “non-rigid body” is a generic expression of objects that are deformed by an external force and whose influence cannot be ignored in measuring the height of the center of gravity.

(Sentence 5)

<Description of correction of load signal detected by load cell>
By the way, with the free vibration of the 3rd mounting base 13 in the horizontal direction, the load cells 21 to 24 become rotational vibration. As a result, the load acting in the axial direction of the load cells 21 to 24 is a function of the rotation angle θ. Now, it is assumed that the load P _i ′ (t) detected by the load cells 21 to 24 is the axial load.

ただし、Ｆｉ（ｔ）およびθはそれぞれ次式（５９）および式（６０）で表わされる。

ここに、Ｆ_ｉ（ｔ）は、各ロードセル２１〜２４に生じる復元力Ｆの符号を逆にしたものである。
前記式（５８）により次式（５８）´が得られる。

この式（５８）´によりＰ_ｉ（ｔ）がＰ_ｉ´（ｔ）とｙ_０（ｔ）から求まることがわかる。
なお、傾斜補正の成されたデジタルロードセルを用いる場合は、その出力はＰ_ｉ（ｔ）であるから、上述の補正は不要となる。 At this time, P _i ′ (t) can be expressed by the following equation (58).

However, Fi (t) and θ are represented by the following equations (59) and (60), respectively.

Here, F _i (t) is obtained by reversing the sign of the restoring force F generated in each of the load cells 21 to 24.
The following equation (58) ′ is obtained from the equation (58).

From this equation (58) ′, it can be seen that P _i (t) is obtained from P _i ′ (t) and y ₀ (t).
When a digital load cell with tilt correction is used, the output is P _i (t), and thus the above correction is unnecessary.

<Description of Measurement Operation of Center of Gravity Height Position of Center of Gravity Position Measurement Apparatus of First Embodiment>
The measurement operation of the center-of-gravity height position of the center-of-gravity position measuring apparatus 1 configured as described above will be described below mainly using the functional block diagram of FIG. 6, the flowchart of FIG. 13, and the time chart of FIG. To do. In FIG. 13, the symbol “S” represents a step.
The following description of the measurement operation is an example in the case where the vehicle 3 is a vehicle (cargo truck) carrying a load.

<Description of Processing Contents of Steps S11 to S14>
Wait until the vehicle 3 that has entered the third platform 13 stops (S11).
After the time (t ₁ + Δt) after the minute time Δt has elapsed from the time t ₁ when the vehicle 3 stopped, the horizontal plane gravity center position calculation unit 70 receives the static load signals P _i (i = 1, 2) from the load cells 21 to 24. , together with the read 3,4) to determine the mass of the vehicle 3 (by weight) from the read static load signal _{P i} (S12).
Further, the horizontal plane center-of-gravity position calculation unit 70 calculates k based on the following equation (56) (S13), and executes the processes of step S1 and step T1 (see FIG. 10) described above, respectively. The plane coordinates (x _G , y _G ) of the center of gravity G are calculated (S14).

<Description of Processing Contents of Step S15>
At time t ₂ , the electromagnetic valve control signal generation unit 74 transmits an electromagnetic valve control signal indicating the extension operation of the hydraulic cylinder 40 to the electromagnetic valve 41. As a result, the hydraulic cylinder 40 is extended, and the side surface of the third platform 13 is pushed by the piston rod 40a, so that the horizontal displacement and speed are given to the third platform 13. Thereafter, at a predetermined displacement, the electromagnetic valve control signal generation unit 74 transmits an electromagnetic valve control signal indicating a contraction operation of the hydraulic cylinder 40 to the electromagnetic valve 41. As a result, the hydraulic cylinder 40 is contracted, the contact between the third platform 13 and the piston rod 40a is released, and an initial condition of free vibration is given to the third platform 13. And since the restoring force F from the restoring force generation mechanism with respect to the displacement in the horizontal direction acts on the third platform 13, the third platform 13 freely vibrates in the horizontal direction (y direction).

<Description of processing contents of steps S16 and S17>
(Sentence 6)

<Description of Processing Contents of Step S18>
In between times t ₅ from the third time point t ₄ after the load platform 13 is stationary, the height of the center of gravity position computing unit 73, the dynamic load signal P which is Shutoku static loads signal P _i and step S16 obtained in step S12 ΔP (t) and ΔP ₃₄ (t) are calculated based on _i (t), respectively.

<Description of Processing Contents of Step S19>
In a period from after time t ₅ at time t _6, the height of the center of gravity position computing unit 73 computes the center-of-gravity height h of the center of gravity G of the vehicle 3 based on the following equation (55). Note that the measured value of h is the average value of h calculated by Equation (55) at each sampling time within a predetermined time interval.

<Description of Processing Contents of Step S20>
Then, the front time signal generating unit 75 generates a display signal for causing the display device 62 to display the value of the center of gravity height h obtained as a result of the calculation in step S19. Thereby, the value of the center-of-gravity height h obtained by the calculation in step S19 is displayed on the display device 62.

<Description of Effects of the Center of Gravity Position Measuring Device of the First Embodiment>
According to the center-of-gravity position measuring apparatus 1 of the first embodiment, the three-dimensional center-of-gravity position of the vehicle 3, that is, the horizontal center-of-gravity position G (X _G , Y _G ) and the center-of-gravity height h can be obtained with a simple and inexpensive configuration. It is possible to measure and to provide effective data contributing to prevention of rollover of the vehicle 3 to the driver or the like.

[Second Embodiment]
FIG. 15 is an explanatory diagram of the structure of the center-of-gravity position measuring apparatus according to the second embodiment of the present invention, and is a plan view (a), a cross-sectional view taken along line GG in (a), (H) in (a). -H sectional view (c) and II sectional view (d) of (b) are respectively shown.
Further, FIG. 16 shows a state diagram (a) of loads acting on the first and second wheels when the left and right wheels of the first axle of the vehicle are respectively placed on the first and second platforms. A plan view (b) showing the position of the center of gravity is shown.
Note that in the center of gravity position measuring apparatus 1A of the second embodiment, the same or similar parts as those of the center of gravity position measuring apparatus 1 of the first embodiment are given the same reference numerals and detailed description thereof is omitted. The following description will focus on differences from the gravity center position measuring apparatus 1 of the first embodiment.

<Description of Schematic Configuration of Center of Gravity Position Measuring Device of Second Embodiment>
The center-of-gravity position measuring apparatus 1A shown in FIG. 15 is installed on the first mounting base 11A, the second mounting base 12A, the third mounting base 13A, and the installation base 2, and the third mounting base 13A. The first load cell 21A, the second load cell 22A, the third load cell 23A, and the fourth load cell 24A, and the sixth load cell 26A that is installed on the third platform 13A and supports the first platform 11A, And a seventh load cell 27A that is installed on the third platform 13A and supports the second platform 12A.

<Description of the first to third platforms>
11A of 1st platforms are comprised with the square-shaped plate-shaped member in which the wheel 4a, 5a, 6a of the left side of each axle shaft 7,8,9 of the vehicle 3 can mount 1 each.
The second platform 12A is formed of a rectangular plate-like member on which the right wheels 4b, 5b, 6b of the axles 7, 8, 9 of the vehicle 3 can be placed one by one.
The third platform 13A is formed of a rectangular plate-like member on which all the left and right wheels 4a, 5a, 6a; 4b, 5b, 6b of the vehicle 3 can be placed simultaneously.
The first platform 11A and the second platform 12A are arranged on the third platform 13A on the upstream side of the travel path when the vehicle 3 travels forward, and are integrated with the third platform 13A. Built in.

<Description of the concave portion of the third platform>
As shown in FIG. 16A, a first recess 76a, a second recess 76b, and a third recess 76c are formed at the upstream end of the vehicle forward travel path in the third platform 13A. Yes.
The first recess 76a can accommodate the first platform 11A such that the surface of the first platform 11A and the surface of the third platform 13A are flush with each other. a concave portion formed on the third mounting base 13A so exists a predetermined clearance S ₁ between.
The second recess 76b can accommodate the second platform 12A so that the surface of the second platform 12A and the surface of the third platform 13A are flush with each other. a concave portion formed on the third mounting base 13A so exists a predetermined clearance S ₂ between.
Here, the predetermined clearance _{S 1,} when the left wheel 4a of each axle 7, 8, 9 of the vehicle 3, 5a, 6a are placed on the first mounting base 11A, FLEXIBLE first mounting base 11A is slightly Even so, the size is determined so that the first mounting base 11A does not interfere with the third mounting base 13A. Further, as the predetermined clearance S ₂ is also a predetermined clearance S _1, even bent the second mounting base 12A is slightly in size so that the second mounting base 12A does not interfere with the third mounting base 13A Is determined.
The third recess 76c can accommodate both the sixth load cell 26A and the seventh load cell 27A, and the surface of each of the first platform 11A and the second platform 12A and the surface of the third platform 13A are separated from each other. It is a recessed part formed in the 3rd mount 13A so that these mounts 11A and 12A can be accommodated so that it may become flush.

<Explanation of respective coupling portions of the first platform and the third platform, and the second platform and the third platform>
The first mounting base 11A is accommodated over substantially the left half of the first concave portion 76a and the third concave portion 76c of the third mounting base 13A. The left end portion of the first mounting base 11 </ b> A and the third mounting base 13 </ b> A are coupled by an elastic support body 77.
Here, the elastic support body 77 maintains a support state in which, when an external force is applied to the first mounting base 11A, a reaction force proportional to the displacement generated by the external force is applied to the first mounting base 11A. It is comprised with the member which can do. In the present embodiment, the plate-like member constituting the first mounting base 11A and the plate-like member constituting the third mounting base 13A are integrally joined, and an upward convex R chamfer is applied to the joint portion. Thus, an elastic support 77 is formed.
The second mounting base 12A is accommodated over substantially the right half of the second recess 76b and the third recess 76c of the third mounting base 13A. The right end portion of the second mounting table 12A and the third mounting table 13A are also coupled by an elastic support 77.

<Description of Arrangement of First Load Cell to Fourth Load Cell>
21 A of 1st load cells are arrange | positioned so that the left corner | angular part in the vehicle forward travel path | route upstream in the 3rd mounting base 13A can be supported from lower side. Here, the center point of the first load cell 21A and the elastic support point of the first mounting base 11A by the elastic support body 77 coincide with each other in the vertical direction.
The second load cell 22A is disposed so that the left corner of the third platform 13A on the downstream side of the vehicle forward travel path can be supported from below.
The third load cell 23A is arranged so that the right corner of the third platform 13A on the upstream side of the vehicle forward travel path can be supported from below. Here, the center point of the third load cell 23 </ b> A and the elastic support point of the second mounting base 12 </ b> A by the elastic support body 77 coincide with each other in the vertical direction.
The fourth load cell 24A is arranged so that the right corner of the third platform 13A on the downstream side of the vehicle forward travel path can be supported from below.

<Arrangement explanation of 6th load cell and 7th load cell>
The sixth load cell 26A is installed in the third recess 76c and is arranged so as to support the right side of the first mounting base 11A from the lower side.
The seventh load cell 27A is installed in the third recess 76c and is arranged so as to support the left side of the second mounting table 12A from the lower side.

<Description of measurement of Y _G and B ₁ >
In the structure in which the first platform 11A and the second platform 12A are integrally coupled to each other via the third platform 13A and the elastic support body 77, B _i (B ₁ ) Can only be determined. The reason is that all the axial loads on the third platform 13A act on the first load cell 21A and the third load cell 23A.
For the measurement of _YG, the measurement of B ₁ and b ₁ , b ₁ ′ is indispensable.

<Determination of the description of _{B 1:} see FIG. 16>
The following formulas (61), (62), (63), and (64) are established regarding the load acting on the first platform 11A and the second platform 12A and the reaction force from the load cells 21A, 23A, 26A, and 27A.
P ₆ = W _L1 b ₁ / b ₀ (61)
P ₇ = W _R1 b ₁ ′ / b ₀ (62)
P ₁ = W _L1 (b ₁ ′ + B ₁ ) / b + W _R1 b ₁ ′ / b (63)
P ₃ = W _R1 (b ₁ + B ₁ ) / b + W _L1 b ₁ / b (64)

From the equations (61) to (64), b ₁ can be obtained from the following equation (65), and b ₁ ′ can be obtained from the following equation (66).
b ₁ = αbP ₆ / {P ₁ + α (P ₆ −P ₇ )} (65)
b ₁ ′ = αbP ₇ / {P ₃ + α (P ₇ −P ₆ )} (66)
Here, α = b ₀ / b.

By substituting the formula (65) following equation (66) (67), can be obtained _{B 1.}
B ₁ = b− (b ₁ + b ₁ ′) (67)

<Description of how to obtain the _{Y G:} see FIGS. 7 and 16>
As is clear from FIG. 7A, Y _G can be obtained from the following equation (68).
Y _G = y _G −f (68)

Here, f is obtained from the following equation (69) on the assumption that it is approximately equal to f ₁ .
_{f = b / 2- (b 1} + B 1/2)
= (B ₁ '-b ₁ ) / 2 (69)

In FIG. 16A, the following equation (70) is established from the balance of moments.
(B / 2 + y _G ) P = bP ₁₂ (70)

From the above formula (70), y _G can be expressed as the following formula (71).
y _G = b (P ₁₂ / P−1 / 2) (71)

The center-of-gravity position Y _G in the width direction of the vehicle 3 can be obtained from the equations (68), (69), and (71).

<Description of Measurement Operation of Horizontal Center of Gravity Position of Center of Gravity Position Measurement Device of Second Embodiment>
Next, the measurement operation of the horizontal center of gravity position of the center of gravity position measuring apparatus 1A will be described below mainly using the functional block diagram of FIG. 6 and the flowchart of FIG. In FIG. 17, symbols “S” and “T” each represent a step.

<Description of processing contents of steps S21 and T21>
The width-direction center-of-gravity position calculation unit 71 reads the load signals of the first load cell 21A, the third load cell 23A, the sixth load cell 26A, and the seventh load cell 27A, and the read load signals and the equations (65) (66) (67 ) and on the basis, as well as calculating the effective tread widths _{B 1,} based on the equation (65) (66) (69), the distance between the X-axis and the x-axis (center line CL _T and the center line CL _S (Distance) f ₁ is calculated (S21).
Moreover, the width direction gravity center position calculation unit 71 reads the load signals of the first load cell 21A to the fourth load cell 24A, and based on the read load signal and the equation (71), the vehicle 3 in the coordinate system O-XY. calculating a centroid position _{y G} in the width direction (T21).

<Description of Processing Contents of Step S22 to Step S24>
Widthwise center-of-gravity position computing unit 71, and _{f 1} calculated in step S21, based on the _{y G} calculated in step T21, the equation (68), the width direction of the vehicle 3 in the coordinate system O-XY calculating a center of gravity position _{Y G} (S22).
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the width direction gravity center position calculation unit 71 (S23). Thereby, the value of the barycentric position in the width direction of the vehicle 3 is displayed on the display device 62 (S24).

<Description of Processing Contents of Step T21 to Step T23>
The full length direction gravity center position calculation unit 72 reads the load signals of the first load cell 21A to the fourth load cell 24A, and based on the read load signals and the equations (16) and (27), the inter-axle distances l ₁ , l ₂ and the center of gravity of the vehicle 3 in the full length direction in the coordinate system O-XY based on the calculated values of the inter-axle distances l ₁ and l ₂ and the expressions (28), (30), and (34). calculating the position _{X G} (T21).
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the full length direction gravity center position calculation unit 72 (T22). Thereby, the value of the barycentric position in the full length direction of the vehicle 3 is displayed on the display device 62 (T23).

<Description of Measurement Operation of Center of Gravity Height Position of Center of Gravity Position Measurement Device of Second Embodiment>
In addition, about the measurement operation | movement of the gravity center height position of 1 A of gravity center position measuring apparatuses of 2nd Embodiment, it is the theoretical description of how to obtain | require the gravity center height h of the vehicle 3 by the gravity center position measuring apparatus 1 of 1st Embodiment. The meanings of symbols used in the theoretical formula are newly defined as follows, and then the mounting assembly 80A (explanation of later definition) is determined by the operation of the expansion and contraction of the hydraulic cylinder 40 and the restoring force from the restoring force generating mechanism. In the horizontal direction, the same operation as the measurement operation of the center-of-gravity height position of the center-of-gravity position measurement apparatus 1 of the first embodiment is basically performed. Thereby, the value of the center of gravity height h of the vehicle 3 is obtained, and the obtained value of the center of gravity height h is displayed on the display device 62.

<Explanation of new definitions of symbols used in the theoretical formula for determining the height of the center of gravity of a vehicle>
The meanings of symbols in FIGS. 11 and 12 and symbols used in the theoretical formula are newly defined as follows. In the following, only newly defined items will be described.
G ₀ : A mounting assembly including the first mounting table 11A, the second mounting table 12A and the third mounting table 13A, the sixth load cell 26A and the seventh load cell 27A, and elastic supports 77 and 77. Center of gravity of 80A a: Distance between load cell 21A (23A) and load cell 22A (24A) b: Distance between load cell 21A (22A) and load cell 23A (24A) c: Height of mounting assembly 80A H: Height of load cells 21A-24A (height of elastic body 31)
P _i : Static load acting on each of the load cells 21A to 24A (i = 1, 2, 3, 4)
m ₀ : Mass of the mounting assembly 80A e: Distance from the lower surface of the mounting assembly 80A to the center of gravity G ₀ P _i (t): Dynamic load acting on the load cells 21A to 24A (i = 1, 2, 3, 4)
F ₁₂ (t): Sum of forces acting on the mounting assembly 80A from the load cells 21A, 22A in the horizontal direction F ₃₄ (t): Sum of forces acting on the mounting assembly 80A in the horizontal direction from the load cells 23A, 24A

<Description of Effects of Center of Gravity Position Measuring Device of Second Embodiment>
According to the center-of-gravity position measuring apparatus 1A of the second embodiment, the same operational effects as those of the center-of-gravity position measuring apparatus 1 of the first embodiment can be obtained.
Furthermore, according to the center-of-gravity position measuring apparatus 1A of the second embodiment, the first mounting base 11A and the third mounting base 13A are coupled by the elastic support body 77, and the second mounting base 12A and the second mounting base 12A are connected. 3A and 13B are coupled by the elastic support body 77, and the first platform 11A and the second platform 12A are integrally incorporated in the third platform 13A. The apparatus can be made compact, and the fifth load cell 25 and the eighth load cell 28 that are required in the center-of-gravity position measuring apparatus 1 of the first embodiment can be omitted to simplify the apparatus. Can do.

[Third Embodiment]
FIG. 18 is an explanatory view of the structure of the center-of-gravity position measuring apparatus according to the third embodiment of the present invention, and is a cross-sectional view taken along line JJ in (a) and (a) of FIG. The L section enlarged view (d) of -K sectional view (c) and (b) is shown, respectively.
FIG. 19 shows a state diagram of a load acting on the platform when the vehicle is mounted on the second platform.
Note that in the third embodiment, the same or similar parts as those in the above embodiments are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted. In the following, differences from the above embodiments are mainly described. It will be explained in the following.

<Description of Schematic Configuration of Center of Gravity Position Measuring Device According to Third Embodiment>
The center-of-gravity position measuring apparatus 1B shown in FIG. 18 includes a first platform 11B and a second platform 12B.
The first platform 11B is disposed on the installation base 2 on the upstream side of the travel route when the vehicle 3 such as a truck or trailer travels forward.
The second platform 12B is disposed on the downstream side of the forward travel path of the vehicle 3 with respect to the first platform 11B on the installation base 2.

<Description of the first to third platforms>
The first platform 11 </ b> B is composed of a rectangular plate-like member on which the left wheels 4 a, 5 a, 6 a of the axles 7, 8, 9 of the vehicle 3 can be placed one by one.
The second platform 12 is composed of a rectangular plate-like member on which all the left and right wheels 4a, 5a, 6a; 4b, 5b, 6b of the vehicle 3 can be placed simultaneously.

<Description of Arrangement of First Load Cell to Fourth Load Cell>
A first load cell 21B, a second load cell 22B, a third load cell 23B, and a fourth load cell 24B are interposed between the installation base 2 and the second platform 12B.
The first load cell 21B is arranged so that the left corner of the second platform 12B on the upstream side of the vehicle forward travel path can be supported from below.
The second load cell 22B is disposed so that the left corner of the second platform 12B on the downstream side of the vehicle forward travel path can be supported from below.
The third load cell 23B is arranged so that the right corner of the second platform 12B on the upstream side of the vehicle forward travel path can be supported from below.
The fourth load cell 24B is arranged so that the right corner of the second platform 12B on the downstream side of the vehicle forward travel path can be supported from below.

<Explanation of arrangement of fifth and sixth load cells>
A fifth load cell 25B and a sixth load cell 26B are interposed between the installation base 2 and the first mounting base 11B.
The fifth load cell 25B is arranged so as to support the left side portion of the first mounting base 11B from the lower side.
The sixth load cell 26B is arranged so as to support the right side portion of the first mounting base 11B from the lower side.

<Description of load vertical transmission mechanism>
The load vertical transmission mechanism 30 described above is interposed between the installation base 2 and the first mounting base 11B.

<Description of how to obtain the _{Y G:} see FIG. 19 (a) (b)>
Y _G can be obtained from the following equation (81) as described above.
Y _G = (W ₁ e ₁ + W ₂ e ₂ + W ₃ e ₃ ) / (W ₁ + W ₂ + W ₃ ) (81)

Moreover, as is clear from FIG. 19 (a), _{e i} can be obtained from the following equation (82).
e _i = b _i + B _i / 2−C _i (82)

b _i can be obtained by the following equation (83).
b _i = (P ₆ / P ₅₆ ) b ₀ (83)

C _i can be expressed by the following equation (84).
C _i = {b _i W _Li + (b _i + B _i ) W _{R i} } / W _i
= B _i + W _Ri B _i / W _i (84)

Meanwhile, _{W i} and _{W Li} can be respectively expressed by the following equation (85) and equation (86).
W _i = W _Li + W _Ri (85)
W _Li = P ⁱ ₅₆ (86)

From the equations (85) and (86), W _Ri can be obtained by the following equation (87).
W _Ri = W _i −P ⁱ ₅₆ (87)

Therefore, b _i and C _i can be obtained. Therefore, as long demanded _{B i,} the equation (82) to be able to determine the _{e i,} using the _{e i,} so that the formulas (81) can be obtained _{Y G.}

<Determination description of _{B i:} FIG. 19 (a), the reference (b)>
The following equations (88) and (89) are established from the balance of moments related to the i-th axle wheel load in the second platform 12B.
b _i W _Li + (b _i + B _i ) W _R ⁱ −bP ⁱ ₃₄ = 0 (88)
b _i W _Li + (b _i + B _i ) (W _i −W _Li ) −bP ⁱ ₃₄ = 0 (89)

These formula (88) (89) from _{B i} can be calculated as shown in the following equation (90).
B _i = (bP ⁱ ₃₄ −b _i W _i ) / (W _i −W _Li ) (90)
However,
P ¹ ₃₄ = P ₃₄ (t) (0 <t <t ₁ )
P ² ₃₄ = P ₃₄ (t) −P ¹ ₃₄ (t ₂ <t <t ₃ )
P ³ ₃₄ = P ₃₄ (t) −P ² ₃₄ (t ₄ <t <t ₅ )
It is.
Incidentally, _{W i} from FIG _{8, P} 34 (t) can be obtained from FIG. 19 (b).

<Description of Measuring Operation of Horizontal Center of Gravity Position of Center of Gravity Position Measurement Device of Third Embodiment>
Next, the measurement operation of the horizontal gravity center position of the gravity center position measurement apparatus 1B of the third embodiment will be described below mainly using the functional block diagram of FIG. 6 and the flowchart of FIG. In FIG. 20, symbols “S” and “T” each represent a step.

<Description of Processing Contents of Step S31 to Step S33>
Widthwise center-of-gravity position computing unit 71 reads the load signals of the first load cell 21B~ sixth load cell 26B, respectively, and the load signal read, based on the above formula (90), as well as calculating the effective tread widths B _i Then, e _i is calculated from the calculated effective tread width B _i and the equation (82), and the width of the vehicle 3 in the coordinate system O-XY is calculated from the equation (81) based on the calculated e _i. It calculates a direction of the _{Y G} (S31).
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the width direction gravity center position calculation unit 71 (S32). Thereby, the value of the barycentric position in the width direction of the vehicle 3 is displayed on the display device 62 (S33).

<Description of Processing Contents of Step T31 to Step T33>
The full length direction gravity center position calculation unit 72 reads the load signals of the first load cell 21B to the fourth load cell 24B, and based on the read load signals and the equations (16) and (27), the inter-axle distances l ₁ , l ₂ and the center of gravity of the vehicle 3 in the full length direction in the coordinate system O-XY based on the calculated values of the inter-axle distances l ₁ and l ₂ and the expressions (28), (30), and (34). It computes the position _{X G} (T31).
Then, the display signal generation unit 75 generates a display signal that causes the display device 62 to display the calculation result by the full length direction gravity center position calculation unit 72 (T32). Thereby, the value of the barycentric position in the full length direction of the vehicle 3 is displayed on the display device 62 (T33).

<Description of Measurement Operation of Center of Gravity Height Position of Center of Gravity Position Measurement Device of Third Embodiment>
In addition, about the measurement operation | movement of the gravity center height position of the gravity center position measurement apparatus 1B of 3rd Embodiment, it is the theoretical description of how to obtain | require the gravity center height h of the vehicle 3 by the gravity center position measurement apparatus 1 of 1st Embodiment. The meanings of the symbols used in the theoretical formula are newly defined as follows, and the second platform 12B is freely vibrated in the horizontal direction by the operation of the expansion and contraction of the hydraulic cylinder 40 and the restoring force from the restoring force generating mechanism. Thus, basically the same operation as the measurement operation of the center-of-gravity height position of the center-of-gravity position measurement apparatus 1 of the first embodiment is performed. Thereby, the value of the center of gravity height h of the vehicle 3 is obtained, and the obtained value of the center of gravity height h is displayed on the display device 62.

<Explanation of new definitions of symbols used in the theoretical formula for determining the height of the center of gravity of a vehicle>
The meanings of symbols in FIGS. 11 and 12 and symbols used in the theoretical formula are newly defined as follows. In the following, only newly defined items will be described.
G ₀ : Center of gravity of the second platform 12B a: Distance between the load cell 21B (23B) and the load cell 22B (24B) b: Distance between the load cell 21B (22B) and the load cell 23B (24B) c: First 2 height 12B: height of load cells 21B-24B (height of elastic body 31)
P _i : Static load acting on each of the load cells 21B to 24B (i = 1, 2, 3, 4)
m ₀ : Mass of the second mounting table 12B e: Distance from the lower surface of the second mounting table 12B to the center of gravity G ₀ P _i (t): Dynamic load acting on the load cells 21B to 24B (i = 1, 2, 3, 4)
F ₁₂ (t): Sum of forces acting on the second platform 12B in the horizontal direction from the load cells 21B, 22B F ₃₄ (t): Forces acting on the second platform 12B in the horizontal direction from the load cells 23B, 24B Sum of

<Description of Effects of Center of Gravity Position Measuring Device of Third Embodiment>
Also with the barycentric position measuring apparatus 1B of the third embodiment, the same effects as those of the barycentric position measuring apparatus 1 of the first embodiment can be obtained.
Furthermore, according to the center-of-gravity position measuring apparatus 1B of the third embodiment, the second platform 12, the seventh load cell 27, and the eighth load cell 28 are required in the center-of-gravity position measuring apparatus 1 of the first embodiment. Can be omitted, and the apparatus can be simplified.

[Fourth Embodiment]
FIG. 21 is a structural explanatory view of the center-of-gravity position measuring apparatus according to the fourth embodiment of the present invention, and is a cross-sectional view taken along the line MM of FIGS. The cross-sectional view (d) taken along the line OO of the -N line cross-sectional views (c) and (b) is shown, respectively.
Note that in the fourth embodiment, the same or similar parts as those in the above embodiments are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted. In the following, points different from those in the above embodiments are mainly described. It will be explained in the following.

<Description of Schematic Configuration of Center of Gravity Position Measuring Device According to Fourth Embodiment>
The center-of-gravity position measuring apparatus 1C shown in FIG. 21 includes a first loading table 11C, a second loading table 12C, and a first load cell 21C that is installed on the installation base 2 and supports the second loading table 12C. A second load cell 22C, a third load cell 23C, and a fourth load cell 24C, and a sixth load cell 26C that is installed on the second platform 12C and supports the first platform 11C.

<Description of the first platform and the second platform>
11C of 1st platforms are comprised with the square-shaped plate-shaped member in which the wheel 4a, 5a, 6a of the left side of each axle shaft 7,8,9 of the vehicle 3 can mount 1 each.
The second platform 12C is formed of a rectangular plate-like member on which all the left and right wheels 4a, 5a, 6a; 4b, 5b, 6b of the vehicle 3 can be placed simultaneously.
The first platform 11C is arranged on the second platform 12C on the upstream side of the travel path when the vehicle 3 travels forward, and is integrated into the second platform 12C.

<Description of the concave portion of the second platform>
A first recess 58a and a second recess 58b are formed at the upstream end of the vehicle forward travel path in the second platform 12C.
The first recess 58a can accommodate the first platform 11C such that the surface of the first platform 11C and the surface of the second platform 12C are flush with each other. a recess formed in the second mounting base 12C so exists a predetermined clearance S ₃ between.
Here, the predetermined clearance _{S 3,} when the left wheel 4a of each axle 7, 8, 9 of the vehicle 3, 5a, 6a are placed on the first mounting base 11C, FLEXIBLE first mounting base 11C slightly Even so, the size is determined so that the first mounting base 11C does not interfere with the second mounting base 12C.
The second recess 58b can accommodate the sixth load cell 26C, and can accommodate the first platform 11C so that the surface of the first platform 11C and the surface of the second platform 12C are flush with each other. It is a recessed part formed in the 2nd mounting base 12C so that it may become possible.

<Description of the connecting portion between the first platform and the second platform>
The first platform 11C is accommodated from the first recess 58a to the second recess 58b of the second platform 12C. The left end portion of the first mounting base 11C and the second mounting base 12C are also coupled by an elastic support 77.

<Description of Arrangement of First Load Cell to Fourth Load Cell>
The first load cell 21C is disposed so as to be able to support the left corner of the second platform 12C on the upstream side of the vehicle forward travel path from below. Here, the center point of the first load cell 21 </ b> C and the elastic support point of the first mounting base 11 </ b> C by the elastic support body 77 coincide with each other in the vertical direction.
The second load cell 22C is arranged so that the left corner of the second platform 12C on the downstream side of the vehicle forward travel path can be supported from below.
The third load cell 23C is arranged so that the right corner of the second platform 12C on the upstream side of the vehicle forward travel path can be supported from below.
The fourth load cell 24C is arranged so that the right corner of the second platform 12C on the downstream side of the vehicle forward travel path can be supported from below.

<Explanation of 6th load cell arrangement>
The sixth load cell 26C is installed in the second recess 58b and is arranged so as to support the right side of the first mounting base 11C from the lower side.

<Description of Measuring Operation of Horizontal Position of Center of Gravity Position Measuring Device of Fourth Embodiment>
The horizontal plane gravity center position measurement operation of the gravity center position measurement apparatus 1C of the fourth embodiment configured as described above is basically the horizontal plane gravity center position of the gravity center position measurement apparatus 1B of the third embodiment. The same operation as the measurement operation is performed. Thereby, the value of the horizontal center of gravity position of the vehicle 3 is obtained, and the obtained value of the horizontal center of gravity position is displayed on the display device 62.

<Description of Measurement Operation of Center of Gravity Height Position of Center of Gravity Position Measurement Device of Fourth Embodiment>
On the other hand, the measurement operation of the center-of-gravity height position of the center-of-gravity position measurement apparatus 1C according to the fourth embodiment is a theoretical explanation of how the center-of-gravity height measurement apparatus 1 according to the first embodiment calculates the center-of-gravity height h. The meanings of the symbols used in the theoretical formula are newly defined as follows, and the mounting assembly 80C (explanation of later definition) is determined by the expansion / contraction operation of the hydraulic cylinder 40 and the restoring force from the restoring force generating mechanism. In the horizontal direction, the same operation as the measurement operation of the center-of-gravity height position of the center-of-gravity position measurement apparatus 1 of the first embodiment is basically performed. Thereby, the value of the center of gravity height h of the vehicle 3 is obtained, and the obtained value of the center of gravity height h is displayed on the display device 62.

<Explanation of new definitions of symbols used in the theoretical formula for determining the height of the center of gravity of a vehicle>
The meanings of symbols in FIGS. 11 and 12 and symbols used in the theoretical formula are newly defined as follows. In the following, only newly defined items will be described.
G ₀ : Center of gravity of the stage assembly 80C including the first stage 11C and the second stage 12C, the sixth load cell 26C, and the elastic support 77 a: load cell 21C (23C) and load cell 22C ( B: distance between the load cell 21C (22C) and the load cell 23C (24C) c: height of the mounting assembly 80C H: height of the load cells 21C to 24C (height of the elastic body 31) )
P _i : Static load acting on each of the load cells 21C to 24C (i = 1, 2, 3, 4)
m ₀ : Mass of the mounting assembly 80C e: Distance from the lower surface of the mounting assembly 80C to the center of gravity G ₀ P _i (t): Dynamic load acting on the load cells 21C to 24C (i = 1, 2, 3, 4)
F ₁₂ (t): sum of forces acting on the mounting assembly 80C in the horizontal direction from the load cells 21C, 22C F ₃₄ (t): sum of forces acting on the mounting assembly 80C in the horizontal direction from the load cells 23C, 24C

<Description of Effects of Center of Gravity Position Measuring Device of Fourth Embodiment>
According to the center-of-gravity position measuring apparatus 1C of the fourth embodiment, it is possible to obtain the same effects as the center-of-gravity position measuring apparatus 1B of the third embodiment.
Furthermore, according to the center-of-gravity position measuring apparatus 1C of the second embodiment, the first mounting base 11C and the second mounting base 12C are coupled by the elastic support body 77, and the first mounting base 12C is connected to the first mounting base 12C. Since the structure in which the platform 11C is integrated is adopted, the apparatus can be made compact, and the fifth load cell 25B required in the gravity center position measuring apparatus 1B of the third embodiment is omitted. This simplifies the apparatus.

  As described above, the center-of-gravity position measuring apparatus of the present invention has been described based on a plurality of embodiments. However, the present invention is not limited to the configurations described in the above-described embodiments, and the configurations described in the embodiments are appropriately combined. The configuration can be changed as appropriate without departing from the spirit of the invention.

For example, instead of the load vertical transmission mechanism 50 (see FIG. 1D), a load vertical transmission mechanism 90 as shown in FIGS. 22A and 22B may be adopted.
The load vertical transmission mechanism 90 includes a first link 91 and a second link 92 arranged between the second platform 12 and the installation base 2.
A rear end portion of the first link 91 is connected to a bracket 93 provided on the installation base 2 below the rear end portion of the second mounting base 12 by a first pin 94.
A first roller 95 that contacts the lower surface of the front end portion of the second platform 12 is connected to the front end portion of the first link 91 by a second pin 96 so as to be able to roll in the front-rear direction.
The rear end portion of the second link 92 is connected to a bracket 97 provided on the lower surface of the rear end portion of the second platform 12 by a third pin 98.
A second roller 99 that is in contact with the installation base 2 below the front end portion of the second platform 12 is connected to the front end portion of the second link 92 by a fourth pin 100 so as to be able to roll in the front-rear direction.
The central portion of the first link 91 and the central portion of the second link are connected to each other by a fifth pin 101 so as to be rotatable.
The link mechanism including the first link 91, the second link 92, the first roller 95, the second roller 99, and various pins 94, 96, 98, 100, 101 has a predetermined interval in the width direction of the vehicle 3. The second pin 96 and the fourth pin 100 are connected so that the link mechanisms are interlocked with each other.
This load vertical transmission mechanism 90 also transmits the load acting on the seventh load cell 27 and the sixth load cell 28 from the right wheels 4b, 5b, 6b of the vehicle 3 via the second platform 12 only in the vertical direction. Can do.

In the first embodiment, the number of load cells used for the first platform 11 and the second platform 12 is two, but the load vertical transmission is received by four load cells for each platform. The mechanism 50 may be omitted.
The same applies to the first stage 11B of the third embodiment.

Further, instead of the elastic support body 77 (see FIG. 16A), a hinge support body 110 as shown in FIG. 23 may be adopted.
The hinge support 110 connects the bracket 111 provided on the third platform 13A so as to correspond to the left end of the first platform 11A, and the bracket 111 and the left end of the first platform 11A. The load 112 acting on the sixth load cell 26A can be transmitted only in the vertical direction from the left wheels 4a, 5a, 6a of the vehicle 3 via the first platform 11A. ing.
Needless to say, the center point of the first load cell 21A and the pin 112, which is the rotation fulcrum of the hinge support 110, are aligned in the vertical direction.

<Description of other means for giving initial conditions of free vibration to the platform>
In the above-described embodiment, the initial condition of free vibration is given to the third platform 13, the platform assembly 80A, the second platform 12B, or the platform assembly 80C by the expansion and contraction operation of the hydraulic cylinder 40. However, the third mounting 13, the mounting assembly 80 </ b> A, the second mounting 12 </ b> B or the mounting assembly 80 </ b> C and the installation base 2 are connected by the required link 115, whereby the third mounting is achieved. An initial condition of free vibration may be given to the stage 13, the stage assembly 80A, the second stage 12B, or the stage assembly 80C. Hereinafter, as a representative example, a specific configuration will be described, as shown in FIG.

<Explanation of link arrangement and restraint of displacement of platform due to the link>
As shown in FIG. 24B, the link 115 is arranged with an inclination of θ with respect to the x coordinate axis. By this link 115, the displacements x ₀ and y _{0 in} the x direction and the y direction of the third mounting table 13 are constrained to the relationship represented by the following equation (92).

y ₀ = αx ₀ , α = 1 / tan θ (known) (92)

<Description of free vibration of the platform>
The link 115 uses the force received from the vehicle 3 when the vehicle 3 traveling in the positive direction of the x-axis stops before entering the third platform 13. The direction of the free vibration is constrained to a horizontal direction (specific direction u) perpendicular to the link 115 (see FIG. 24B). A restoring force F from a restoring force generation mechanism with respect to a displacement in the u direction acts on the third platform 13. In this way, by applying the restoring force F to the displacement of the third platform 13 in the horizontal direction (u direction), the third platform 13 can be freely vibrated in the horizontal direction (u direction).

前記式（９３）において、ΔＰ_ｙ（ｔ），ΔＰ_３４ｙ（ｔ）は、ロードセル２１〜２４に生じた荷重変化であるが、自由振動はｘ方向へも生じているから、ロードセル２１〜２４で検出される変化量ΔＰ（ｔ），ΔＰ_３４（ｔ）とは異なる。
以下では、ΔＰ_ｙ（ｔ）およびΔＰ_３４ｙ（ｔ）がそれぞれΔＰ（ｔ）およびΔＰ_３４（ｔ）によって求めることができることを示す。なお、添字ｘを付す記号はｘ方向の振動成分によりロードセル２１〜２４に作用する力を表わすものとする。 <Theoretical explanation of how to find the center of gravity height h of the vehicle>
When the free vibration of the third platform 13 is constrained in the horizontal direction (u direction), the force acting on the load cells 21 to 24 by the vibration component in the y direction is denoted by the suffix y and ΔP _y (t) (= ΔP _1y (t) +... + ΔP _4y (t)), ΔP _34y (t) (= ΔP _3y (t) + ΔP _4y (t)) At this time, the theoretical formula of the center of gravity height h is expressed by the following formula (93).

In the equation (93), ΔP _y (t) and ΔP _34y (t) are load changes generated in the load cells 21 to _24. However, since free vibration also occurs in the x direction, in the load cells 21 to 24, This is different from the detected changes ΔP (t) and ΔP ₃₄ (t).
In the following, it is shown that ΔP _y (t) and ΔP _34y (t) can be obtained by ΔP (t) and ΔP ₃₄ (t), respectively. Note that the symbol with the suffix x represents the force acting on the load cells 21 to 24 due to the vibration component in the x direction.

<Theoretical explanation of how to obtain ΔP _y (t)>
ΔP _y (t) can be expressed as follows using ΔP (t) (= ΣΔP _i (t)).

ΔP (t) = ΔP _x (t) + ΔP _y (t) = (1 + 1 / α ² ) · ΔP _y (t)
Therefore, ΔP _y (t) can be expressed by the following equation (94).
ΔP _y (t) = α ² · ΔP (t) / (1 + α ² ) (94)
ΔP _x (t) can be expressed by the following equation (95).
ΔP _x (t) = ΔP (t) / (1 + α ² ) (95)

<Theoretical explanation of how to obtain ΔP _34y (t)>
ΔP _34y (t) can be expressed using ΔP ₃₄ (t) and ΔP (t).
That is,
_{ΔP 34 (t) = ΔP 34x} (t) + ΔP 34y (t)
_Therefore , ΔP _34y (t) can be expressed by the following equation (96).
_{ΔP 34y (t) = ΔP 34} (t) -ΔP 34x (t)
≈ΔP ₃₄ (t) −ΔP _x (t) / 2 (∵b / 2 >> d)
= ΔP ₃₄ (t) −ΔP (t) / 2 (1 + α ² ) (96)

<Description of measurement operation of horizontal center of gravity position>
Regarding the center-of-gravity position measuring apparatus 1 of the first embodiment, even when the third platform 13 and the installation base 2 are connected by a required link 115, the center-of-gravity position of the first embodiment described above is basically used. The same measurement operation as the measurement operation of the horizontal plane center of gravity position of the measurement apparatus 1 is performed, and the display signal generation unit 75 generates a display signal for displaying the calculation result of the horizontal plane center of gravity position calculation unit 70 on the display device 62. Thereby, the value of the horizontal gravity center position of the vehicle 3 is displayed on the display device 62.

<Explanation of measurement operation of center of gravity height position>
Regarding the center of gravity position measuring apparatus 1 of the first embodiment, the operation of measuring the center of gravity height position when the third platform 13 and the installation base 2 are connected by the required link 115 is mainly shown in FIG. This will be described below with reference to a functional block diagram, a flowchart of FIG. 25, and a time chart of FIG. In FIG. 25, the symbol “S” represents a step.
In the following description of the measurement operation, the vehicle 3 is a vehicle (cargo truck) on which a load is loaded, and the vehicle 3 traveling in the positive direction of the x axis enters and stops the third platform 13. This is an example of measuring the height of the center of gravity of 3.

<Description of Processing Contents of Step S41>
Wait until the vehicle 3 that has entered the third platform 13 stops (S41).
At this time, the link 115 uses the force received from the vehicle 3 when the vehicle 3 enters / stops the third platform 13 to cause free vibration to the third platform 13 in a specific direction (u direction). To give. And since the restoring force F from the restoring force generation mechanism with respect to the displacement in the u direction acts on the third table 13, the third table 13 freely vibrates in the u direction.

<Description of processing contents of steps S42 and S43>
(Sentence 7)

<Description of Processing Contents of Steps S44 to S46>
At time t ₄ from the third time point t ₃ after the load platform 13 is shifted to the stationary state from the free vibration state of the planar center of gravity calculating section 70 reads in a static load signal P _i from the load cell 11 to 14, read i from static load signal _{P i} determining the mass of the vehicle 3 (by weight) (S44).
Further, the planar center-of-gravity calculation unit 70 calculates k based on the following equation (56) (S45), and executes the processes of step S1 and step T1 (see FIG. 10) described above, respectively. The plane coordinates (x _G , y _G ) of the center of gravity G are calculated (S46).

<Description of Processing Contents of Step S47>
Between time t ₄ and time t ₅ , the center-of-gravity height position calculation unit 73 is based on the static load signal P _i acquired in step S 44 and the dynamic load signal P _i (t) stored in the memory 68. ΔP (t) and ΔP ₃₄ (t) are respectively calculated.

ΔＰ_ｙ（ｔ）＝α^２・ΔＰ（ｔ）／（１＋α^２） ・・・（９４）
ΔＰ_３４ｙ（ｔ）＝ΔＰ_３４（ｔ）−ΔＰ（ｔ）／２（１＋α^２） ・・・（９６）
<Description of Processing Contents of Step S48>
In a period from the time _{t 5} the time _{t 6,} the height of the center of gravity position computing unit 73, the following equation (93), (94), calculates the center-of-gravity height h of the center of gravity G of the vehicle 3 based on (96).

ΔP _y (t) = α ² · ΔP (t) / (1 + α ² ) (94)
ΔP _34y (t) = ΔP ₃₄ (t) −ΔP (t) / 2 (1 + α ² ) (96)

<Description of Processing Contents of Step S49>
Then, the display signal generation unit 75 generates a display signal for causing the display device 62 to display the value of the center of gravity height h obtained as a result of the calculation in step S48. Thereby, the value of the center-of-gravity height h obtained by the calculation in step S48 is displayed on the display device 62.

<Description of effects>
In the center-of-gravity position measuring apparatus 1 according to the first embodiment, according to the configuration in which the third mounting base 13 and the installation base 2 are connected by the required link 115, the vehicle 3 becomes the third mounting base 13. Since the third platform 13 is caused to freely vibrate in the u direction by the link 115 using the force received by the third platform 13 from the vehicle 3 when entering or stopping, the first implementation The hydraulic cylinder 40, the electromagnetic valve 41, the hydraulic pump 42, the electric motor 43, the tank 44, the hydraulic piping, and the like that are required in the center-of-gravity height measuring apparatus 1 can be omitted, and the apparatus configuration can be simplified. be able to.

<Overview of modified example of mounting support structure>
In the center-of-gravity position measuring apparatus 1 according to the first embodiment, as shown in FIG. 3, double-convex loading type column type load cells 21 to 24, an upper receiving member 36, and a lower receiving member 38. Although the structure for supporting the third platform 13 is employed, the present invention is not limited to this, and a platform support structure as shown in FIG. 27 may be employed. The same applies to other embodiments.

<Description of another example (1) of the platform support structure>
27 is mounted on the installation base 2 so as to be positioned between the pair of leg members 121 and 121 suspended from the third stage 13 and the pair of leg members 121 and 121. A pair of upright support members 122, 122; an axial load cell 123 connecting the upper ends of the pair of support members 122, 122; a lower pin 124 connecting the lower ends of the pair of leg members 121, 121; A suspension ring member 125 spanned between the shaft-shaped load cell 123 and the lower pin 124 is provided.
The axial load cell 123 has a recess 126 that is recessed with a predetermined radius of curvature over the entire circumference at the center in the axial direction. The upper part of the suspension ring member 125 is hooked on the recess 126. Similarly, the lower pin 124 has a recessed portion 127 that is recessed with a predetermined radius of curvature over the entire circumference at the center in the axial direction. The lower part of the suspension ring member 125 is hooked on the recess 127.
In this platform support structure, a restoring force against the displacement of the third platform 13 in the front-rear direction (horizontal direction orthogonal to the axis of the axial load cell 123) acts by the action of the pendulum around the axis of the axial load cell 123. To do. Further, since the upper portion of the suspension ring member 125 is hooked on the recess portion 126 of the axial load cell 123, when the suspension ring member 125 moves in the axial direction of the axial load cell 123, the suspension ring member 125 is moved to the recess portion. A swing-back force that returns to the lowest part of 126 acts. Due to the action of the swing back force, a restoring force against the displacement of the third platform 13 in the left-right direction (the axial direction of the axial load cell 123) acts.

<Description of another example (2) of the platform support structure>
Moreover, it can replace with the mounting base support structure shown in FIG. 27, and can also employ | adopt the mounting base support structure shown in FIG.
In the mounting support structure shown in FIG. 28, the pair of leg members 121, 121 suspended from the third mounting base 13 and the installation base 2 so as to be positioned between the pair of leg members 121, 121. A pair of support members 122, 122 standing upright, an upper pin 128 connecting the upper ends of the pair of support members 122, 122, a lower pin 124 connecting the lower ends of the pair of leg members 121, 121, A suspension ring member 129 is provided between the upper pin 128 and the lower pin 124.
The upper pin 128 has a recessed portion 130 that is recessed with a predetermined radius of curvature over the entire circumference at the center in the axial direction. The upper part of the suspension ring member 129 is hooked on the recess 130.
A tension load cell 131 is interposed at the center of the hanging ring member 129 in the vertical direction.
In this mounting table support structure, a restoring force acts on the displacement of the third mounting table 13 in the front-rear direction (horizontal direction orthogonal to the axis of the upper pin 128) by the action of the pendulum around the axis of the upper pin 128. Further, since the upper portion of the suspension ring member 129 is hooked on the recess portion 130 of the upper pin 128, when the suspension ring member 129 moves in the axial direction of the upper pin 128, the suspension ring member 129 is moved to the recess portion 130. A rocking force to return to the lowest part acts. Due to the action of the swing back force, a restoring force against the displacement of the third platform 13 in the left-right direction (the axial direction of the upper pin 128) acts.

<Description of another example (3) of the platform support structure>
Moreover, it can replace with the mounting base support structure shown in FIG. 27, and can also employ | adopt the mounting base support structure shown in FIG.
29, the upper receiving member 141 fixed to the lower surface of the third mounting base 13, the lower receiving member 142 fixed to the installation base 2, and the lower receiving member 142. In the mounting support structure shown in FIG. A load cell 143 installed on the upper side and a steel ball 144 disposed between the load cell 143 and the upper receiving member 141 are provided.
The upper receiving member 141 is formed with an upper receiving seat 145 that is interposed between the upper receiving member 141 and the steel ball 144. The upper receiving seat 145 has a concave seat surface 146 that comes into contact with the spherical surface 144 a of the steel ball 144.
The load cell 143 is formed with a lower receiving seat 147 interposed between the steel ball 144 and the load cell 143. The lower receiving seat 147 has a concave seat surface 148 that comes into contact with the spherical surface 144 a of the steel ball 144.
The radius of curvature of the recessed seat surfaces 146 and 148 is set to be larger than the radius of curvature of the spherical surface 144a of the steel ball 144.
The restoring force generation mechanism includes a spherical surface 144a of the steel ball 144 and a concave seat surface 146 of the upper receiving seat 145, and a spherical surface 144a of the steel ball 144 and a concave seat surface 148 of the lower receiving seat 147. A restoring force is generated with respect to the horizontal displacement of the table 13.

<Explanation of terms>
The hydraulic cylinder 40 corresponds to the “actuator” of the present invention.
The configuration including the displacement sensor 45 and the acceleration sensor 46 corresponds to the “vibration state quantity detecting means” of the present invention.
The configuration including the upper convex surface 34 of the elastic body 31 and the horizontal seating surface 37 of the upper receiving member 36, and the lower convex surface 35 of the elastic body 31 and the horizontal seating surface 39 of the lower receiving member 38 is the “restoring force generation” of the present invention. Corresponds to "mechanism".
A configuration including the leg member 121, the support member 122, the axial load cell 123, the lower pin 124, and the suspension ring member 125 corresponds to the “restoring force generation mechanism” of the present invention.
A configuration including the leg member 121, the support member 122, the upper pin 128, the lower pin 124, and the suspension ring member 129 corresponds to the “restoring force generation mechanism” of the present invention.
The structure including the spherical surface 144a of the steel ball 144 and the concave seating surface 146 of the upper receiving seat 145 and the spherical surface 144a of the steel ball 144 and the concave seating surface 148 of the lower receiving seat 147 is the “restoring force generating mechanism” of the present invention. Equivalent to.

<Description of another example of acceleration detecting means>
In the first embodiment, the example in which the acceleration sensor 46 is used as the acceleration detection means for detecting the acceleration of the third platform 13 in the free vibration state has been described. However, the present invention is not limited to this. For example, the center-of-gravity height position calculation unit 73 can obtain the acceleration of the third platform 13 by executing the differential calculation twice based on the detection signal of the displacement sensor 45. In this case, the acceleration sensor 46 becomes unnecessary. There may be a mode in which the differential calculation is not performed by the center-of-gravity height position calculation unit 73 but an acceleration calculation unit is provided separately, and the acceleration calculation unit executes the differential calculation. The same applies to other embodiments.

<Description of another example of measurement of dynamic load fluctuation ΔP (t)>
(Sentence 8)

  The center-of-gravity position measuring apparatus of the present invention has the characteristic that the three-dimensional center-of-gravity position of a vehicle can be measured at a fixed position with a simple and inexpensive configuration. It can use suitably for the use of provision.

DESCRIPTION OF SYMBOLS 1 Center-of-gravity position measuring device 3 Vehicle 11 1st mounting base 12 2nd mounting base 13 3rd mounting base 21 1st load cell 22 2nd load cell 23 3rd load cell 24 4th load cell 25 5th load cell 26 6th load cell 27 Seventh load cell 28 Eighth load cell 31 Elastic body 34 Upper convex surface 35 Lower convex surface 36 Upper receiving member 37 Horizontal seating surface 38 Lower receiving member 39 Horizontal seating surface 40 Hydraulic cylinder 45 Displacement sensor 46 Acceleration sensor 70 Horizontal plane center of gravity position calculation unit 71 Width direction gravity center position calculation unit (width direction gravity center position calculation means)
72 Full length direction gravity center position calculation unit (Full length direction gravity center position calculation means)
73 Center of gravity height position calculation unit (center of gravity height position calculation means)
77 Elastic support member 110 Hinge support member 115 Link 121 Leg member 122 Support member 123 Axial load cell 124 Lower pin 125 Suspension ring member 128 Upper pin 129 Suspension ring member 144 Steel ball 144a Spherical surface 145 Upper receiving seat 146 Concave seat surface 147 Lower side Seat 148 Concave surface

Claims (8)

A center-of-gravity position measuring device that measures the three-dimensional center of gravity position of a vehicle,
(A) a first platform on which wheels on either the left or right side of the vehicle can be mounted;
(B) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the first platform;
(C) a second platform on which the left or right wheel of the vehicle can be placed;
(D) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the second platform;
(E) Width-direction center-of-gravity position calculation that calculates the center-of-gravity position in the width direction of the vehicle based on load signals from a plurality of load cells that support the first platform and a plurality of load cells that support the second platform. Means,
(F) a third platform on which all the left and right wheels of the vehicle can be mounted;
(G) a plurality of load cells arranged at predetermined intervals in the entire length direction of the vehicle and supporting the third mounting table;
(H) a full-length-direction center-of-gravity position calculating means for calculating a center-of-gravity position in the full-length direction of the vehicle based on load signals from a plurality of load cells that support the third platform;
(I) vibration generating means for freely vibrating the third platform on which the vehicle is mounted in the horizontal direction;
(J) vibration state quantity detecting means for detecting either or both of the displacement and acceleration of the third platform in a free vibration state;
(K) Center-of-gravity height position calculating means for calculating the center-of-gravity height position of the vehicle based on load signals from a plurality of load cells that support the third platform and detection signals from the vibration state quantity detecting means; A center-of-gravity position measuring device comprising:   The first stage and the third stage are coupled by an elastic support or a hinge support, and the second stage and the third stage are an elastic support or a hinge support. The center-of-gravity position measuring device according to claim 1, wherein the center-of-gravity position measuring device is coupled by the step.   The vibration generating means includes an actuator that applies a horizontal force to the third platform, and a restoring force generating mechanism that generates a restoring force with respect to a horizontal displacement of the third platform. The center-of-gravity position measuring device according to claim 1 or 2.   The vibration generating means includes a link that applies a free vibration to the third platform in a specific direction by using a force received from the vehicle when the vehicle that has entered the third platform stops. The center-of-gravity position measuring apparatus according to claim 1, further comprising a restoring force generating mechanism that generates a restoring force with respect to a horizontal displacement of the stage 3. A center-of-gravity position measuring device that measures the three-dimensional center of gravity position of a vehicle,
(A) a first platform on which wheels on either the left or right side of the vehicle can be mounted;
(B) a plurality of load cells arranged at predetermined intervals in the width direction of the vehicle and supporting the first platform;
(C) a second platform on which all the left and right wheels of the vehicle can be mounted;
(D) a plurality of load cells arranged at predetermined intervals in the width direction and the full length direction of the vehicle and supporting the second platform;
(E) Width-direction center-of-gravity position calculation that calculates the center-of-gravity position in the width direction of the vehicle based on load signals from a plurality of load cells that support the first platform and a plurality of load cells that support the second platform. Means,
(F) a full-length direction center-of-gravity position calculating means for calculating a center-of-gravity position in the full-length direction of the vehicle based on load signals from a plurality of load cells that support the second platform;
(G) vibration generating means for freely vibrating the second platform on which the vehicle is mounted in the horizontal direction;
(H) vibration state quantity detecting means for detecting either or both of the displacement and acceleration of the second platform in a free vibration state;
(I) a center-of-gravity height position calculating unit that calculates a center-of-gravity height position of the vehicle based on load signals from a plurality of load cells that support the second platform and detection signals from the vibration state quantity detecting unit; A center-of-gravity position measuring device comprising:   The center-of-gravity position measuring device according to claim 5, wherein the first platform and the second platform are coupled by an elastic support or a hinge support.   The vibration generating means includes an actuator that applies a horizontal force to the second platform, and a restoring force generating mechanism that generates a restoring force with respect to a horizontal displacement of the second platform. The center-of-gravity position measuring device according to claim 5 or 6.   The vibration generating means includes a link that applies a free vibration to the second platform in a specific direction using a force received from the vehicle that has entered the second platform when the vehicle stops. The center-of-gravity position measuring device according to claim 5 or 6, further comprising a restoring force generating mechanism that generates a restoring force with respect to a horizontal displacement of the stage 2.

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