JP6629691B2 - Sensor packages and self-driving vehicles - Google Patents

Description

  The present invention relates to a sensor device and an automatic driving vehicle.

  2. Description of the Related Art In recent years, applications such as automobile safety support and automatic driving, robot control, and autonomous flight devices called so-called drones have become widespread. In these applications, detecting the posture and angle of the target is important for the control. For this reason, inertial sensors that detect angular velocity and acceleration are important components in these applications.

  Furthermore, an inertial sensor having a practical level of accuracy and precision has come to be marketed today by using a micromechanical device called MEMS (Micro Electro Mechanical Systems), which is manufactured using a semiconductor fine processing technique. Since an inertial sensor manufactured by MEMS is manufactured by a semiconductor process, sensor elements (mechanical structures for detecting inertial force) can be manufactured in parallel and in large quantities. This has led to a reduction in the price of the conventionally expensive inertial sensor, and has become a driving force for generalizing the above-mentioned applications.

In general, there are two main principles of posture detection using an inertial sensor. The first is to use the fact that gravity is always 1 G (9.8 m / s ² ) in the vertical direction, and to determine in which direction gravity is applied from an acceleration sensor with sensitivity in each of the X, Y, and Z directions Is a method of obtaining the inclination direction, that is, the posture. According to this principle, when an object is accelerating or in a state where a centrifugal force is applied to an acceleration sensor due to a rotational motion, an error occurs due to the inertial force (disturbance).

  As another principle of attitude detection, there is one that integrates the angular velocity sensor with time and calculates the amount of angle change from the integration start time. This detection principle is essentially unaffected by the acceleration of the object or the application of centrifugal force due to rotational movement to the sensor. This is a feature not found in the principle of detecting a posture using an acceleration sensor.

  However, according to the principle of detecting the posture by time integration, the absolute posture cannot be obtained, and only the relative posture from the initial posture can be obtained. It is possible to define the initial posture by some method and obtain the posture by adding the relative posture. However, since the bias error is integrated by integration, the drift of the offset increases, and the error with respect to the absolute attitude increases with time. Therefore, there is a case where a measurement system combining signal processing, in which the absolute posture is appropriately corrected by the acceleration sensor and the posture is detected by the angular velocity sensor, is used in some cases.

  As a background art in this technical field, there is, for example, Patent Document 1. In Patent Document 1, an inertial measurement device that processes the outputs of a three-axis angular velocity sensor and an acceleration sensor with a Kalman filter and estimates an offset drift of the angular velocity sensor is provided with a fourth angular velocity sensor. A technique for accurately estimating the offset drift of the above is disclosed. Further, Patent Document 2 discloses a sensor in which a redundant detection axis having sensitivity for all the detection axes is provided, and when the detection axis fails, the redundant axis is used in place of the redundant axis. I have.

JP 2012-52904 A JP 2001-264351 A

  As a result of studying an inertial sensor configured to obtain the attitude angle from the integration of the angular velocity and the acceleration as shown in Patent Literature 1, the following problems were clarified. That is, since the absolute attitude cannot be obtained by the angular velocity sensor, it is important to accurately obtain the initial attitude to accurately obtain the absolute attitude using the angular velocity sensor, and it is necessary to improve the accuracy of the acceleration sensor. .

  Patent Document 1 discloses a technique for improving an offset drift or the like of an angular velocity sensor, but does not disclose a technique for improving the accuracy of absolute posture detection. Further, the technique disclosed in Patent Document 2 is for improving the tolerance when a failure occurs, and is not a technique for improving the accuracy of posture detection.

  For example, regarding the improvement of the accuracy of an acceleration sensor, there is a technique using an acceleration sensor having a detection mass with mass, which is called a bulk type as opposed to a MEMS type. However, since it imposes a burden on cost and size, it is not realistic from the viewpoint of realizing an application that has not been widely used due to cost as described in the background art.

  Also, in MEMS sensors, by developing a detection element with a particularly large detection mass, or by developing a low-noise circuit using a large-sized MOS (Metal-Oxide Semiconductor) transistor for the detection circuit. It is possible to improve the accuracy of the acceleration sensor. However, in addition to the design cost for development, it also takes time for development.

  The present invention has been made in view of the above problems, and has as its object to improve the detection accuracy of a physical sensor.

  The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows. One is a sensor device including a plurality of physical sensors that output detection results on a plurality of detection axes, each of the plurality of detection axes having a detection direction along the detection axis, and a plurality of physical sensors. A first physical sensor in the sensor has a first detection axis in a plurality of detection axes of the first physical sensor, and a second physical sensor in the plurality of physical sensors is The second physical sensor has a second detection axis among a plurality of detection axes, the first detection axis and the second detection axis overlap, and a detection direction of the first detection axis and The first physical sensor and the second physical sensor are arranged such that a detection direction of a second detection axis is opposite.

  According to the present invention, it is possible to improve the detection accuracy of a physical sensor.

FIG. 3 is a diagram illustrating an example of an inertial sensor according to the first embodiment. FIG. 3 is a top view illustrating an example of a first combined inertial sensor according to the first embodiment. FIG. 3 is a side view illustrating an example of a first combined inertial sensor according to the first embodiment. FIG. 4 is a top view illustrating an example of a second composite inertial sensor according to the first embodiment. FIG. 5 is a side view illustrating an example of a second composite inertial sensor according to the first embodiment. FIG. 3 is a diagram illustrating an example of a signal processing integrated circuit chip. It is a figure showing an example of signal processing of difference calculation. FIG. 4 is a diagram illustrating an example of signal processing of a Kalman filter. FIG. 7 is a diagram illustrating an example in which in-phase noise exists in a sensor output. It is a figure showing an example where uncorrelated noise exists in a sensor output. FIG. 4 is a diagram illustrating a relationship between a sensor output band and a sampling rate. FIG. 13 is a top view illustrating an example of a composite inertial sensor according to the second embodiment. FIG. 13 is a side view illustrating an example of a composite inertial sensor according to the second embodiment. FIG. 13 is a diagram illustrating an example of an inertial sensor according to a third embodiment. FIG. 14 is a diagram illustrating an example of an inertial sensor according to a fourth embodiment. FIG. 15 is a diagram illustrating an example of an inertial sensor according to a fifth embodiment. FIG. 14 is a diagram illustrating an example of an inertial sensor according to a sixth embodiment. FIG. 21 is a diagram illustrating an example of an automobile according to a seventh embodiment.

  In the following embodiments (examples), where necessary for convenience, the description will be made by dividing into a plurality of sections or embodiments, but unless otherwise specified, they are not unrelated to each other. One has a relationship of some or all of the other modifications, details, supplementary explanations, and the like. Further, in the following embodiments, when referring to the number of elements (including the number, numerical value, amount, range, etc.), a case where it is particularly specified, and a case where it is clearly limited to a specific number in principle, etc. However, the number is not limited to the specific number, and may be more than or less than the specific number.

  Further, in the following embodiments, the constituent elements (including element steps, etc.) are not necessarily essential unless otherwise specified, and when it is deemed essential in principle. Needless to say. Similarly, in the following embodiments, when referring to the shapes, positional relationships, and the like of the constituent elements, the shapes are substantially the same unless otherwise specified and in cases where it is considered that it is not clearly apparent in principle. And the like. This is the same for the above numerical values and ranges.

  In the following embodiments, “acceleration” and “angular velocity” can be interchanged with each other unless otherwise specified. However, for the sake of simplicity, one embodiment is described as a combination of “acceleration” and “angular velocity”. It will be shown.

  FIG. 1 is a diagram illustrating an example of an inertial sensor. In the inertial sensor according to the first embodiment, a first composite inertial sensor 102, a second composite inertial sensor 103, a microcontroller (microcomputer or microprocessor) 104, a power regulator IC (Integrated Circuit) ) 105.

  The first composite inertial sensor 102 includes a first acceleration detection axis 108a having an acceleration sensitivity in the positive X direction of FIG. 1, a second acceleration detection axis 108b having an acceleration sensitivity in the Y positive direction of FIG. A first angular velocity detection axis 109 having angular velocity sensitivity in the positive direction (Yaw) around the first Z axis is provided.

  The second composite inertial sensor 103 includes a third acceleration detection axis 106a having an acceleration sensitivity in the negative X direction of FIG. 1 and a fourth acceleration detection axis 106b having an acceleration sensitivity in the positive Z direction of FIG. , A second angular velocity detection axis 107 having angular velocity sensitivity in the positive direction (Roll) around the Y axis in FIG.

  Therefore, each of the first compound inertial sensor 102 and the second compound inertial sensor 103 is a so-called three-axis detection sensor having two acceleration detection axes and one angular velocity detection axis. A state in which a sensor having a plurality of detection axes is sealed in one package by a packaging technique such as a transfer mold package or a pre-mold package is sometimes referred to as a “sensor module”. That is, in the present embodiment, two three-axis sensor modules are mounted on the sensor package unit 101. It can be said that the sensor module is the smallest unit in which the sensor is mounted.

  Here, the power supply regulator IC 105 converts the power supply voltage supplied from the connector 110 into a voltage suitable for the first composite inertial sensor 102 and the second composite inertial sensor 103, and supplies the voltage via the wiring 111. That is, the first composite inertial sensor 102 and the second composite inertial sensor 103 receive power supply from the same power supply regulator IC 105.

  The microcontroller 104 is connected to the first composite inertial sensor 102 and the second composite inertial sensor 103 by wiring (not shown) of a printed circuit board and the like, and is also connected to the connector 110. The measurement result (output result) of the second composite inertial sensor 103 and information on the attitude of the sensor package unit 101 based on the measurement result are output through the connector 110. Signal processing for calculating the content and attitude of the output signal will be described later.

  FIG. 2 is a top view showing an example of the first composite inertial sensor 102 (sensor module). Here, the Z positive direction in FIG. The first composite inertial sensor 102 includes a package 201, external electrodes 203, a signal processing integrated circuit chip (LSI) 204, an acceleration detection element chip 205, an angular velocity detection element chip 206, a pad 207, and a bonding wire 208. Then, for example, the pad 207 and the angular velocity detecting element chip 206 are connected by wiring.

  FIG. 3 is a side view showing an example of the first composite inertial sensor 102. Here, the Y negative direction in FIG. The package 201 includes a package lid 202 omitted in FIG. 1 and is an exterior for protecting a semiconductor chip and the like included therein, and is, for example, a pre-mold package. As shown in FIG. 2, in addition to the structure having a cavity (chamber) in the package 201, a structure in which the cavity is filled with a thermosetting resin to form a package may be used. In FIG. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals.

  As described above, since the package 201 includes the acceleration detection element chip 205 and the angular velocity detection element chip 206, even if the package 201 is a single unit, its output is an output of two-axis acceleration and one axis of angular velocity. This is the output of the module.

  The signal processing integrated circuit chip 204 is fixed to the cavity in the package 201 with an adhesive (not shown), and the acceleration detection element chip 205 and the angular velocity detection element chip 206 are respectively bonded to the signal processing integrated circuit chip 204 with an adhesive. (Not shown) or the like. Then, the signal processing integrated circuit chip 204, the acceleration detection element chip 205, and the angular velocity detection element chip 206 fixed in the package 201 are electrically connected through the pad 207.

  First, how the acceleration detection element chip 205 and the signal processing integrated circuit chip 204 detect and process acceleration will be described. On the acceleration detection element chip 205, a first detection element 211 for detecting acceleration and a second detection element 212 are arranged with orthogonal detection axes. For this reason, the acceleration detection element chip 205 can detect biaxial acceleration. Note that the first detection element 211 and the second detection element 212 are portions respectively surrounded by broken lines in FIG.

  The first detection element 211 is an element for detecting the acceleration in the Y direction in FIG. 2, and a spring-mass system in which the detection mass portion 211c is suspended from the anchor portion 211a through the spring portion 211f is constructed. Here, when a static linear acceleration is applied,

ｍ：検出マス部２１１ｃの質量、ａ：印加された加速度、
ｋ：ばね部２１１ｆのばね定数、ｘ：変位量
の式１に従った変位が発生する。

m: mass of the detection mass unit 211c, a: applied acceleration,
k: a spring constant of the spring portion 211f, and x: displacement occurs according to the equation 1 of displacement.

  This displacement causes a change in the gap between the detection mass portion 211c and the detection electrode 211b, and changes the capacitance. The signal processing integrated circuit chip 204 electrically obtains this change in capacitance and calculates acceleration. This detailed configuration will be described later. The second detection element 212 also has the same structure as the first detection element 211, but has a different detection axis, so that the arrangement of the detection electrodes is different.

  Next, the principle of how the angular velocity detecting element chip 206 and the signal processing integrated circuit chip 204 detect and process angular velocity will be described. On the angular velocity detecting element chip 206, a detecting element 210 for detecting an angular velocity is arranged. The detection element 210 is an element that detects the angular velocity around the Z-axis in FIG. 2 and is a part surrounded by a broken line in FIG. 2 and a spring mass in which the detection mass portion 210f is suspended from the anchor portion 210c through the spring portion 210g. A system is built.

  Here, the detection mass section 210f is driven by an AC signal applied from the signal processing integrated circuit chip 204 to a capacitor constituted by the detection mass section 210f and the drive electrode 210b, so that a constant frequency and vibration Vibrates with amplitude (drive vibration). In order to maintain a constant frequency and vibration amplitude, a driving monitor electrode 210a is separately provided, and the frequency and vibration amplitude in the Y direction are input to the signal processing integrated circuit chip 204 as a change in capacitance. The details of the signal processing integrated circuit chip 204 relating to the drive vibration will be described later.

  Here, when the displacement speed caused by the vibration of the detection mass unit 210f in the Y direction is set to v, when the angular velocity Ω around the Z axis is applied,

の式に従ったコリオリ力が図２のＸ方向に発生する。
Ｆ：コリオリ力、ｍ：検出マス部２１０ｆの質量、
Ω:印加角速度、ｖ： 検出マス部２１０ｆの変位速度

A Coriolis force is generated in the X direction in FIG.
F: Coriolis force, m: mass of the detection mass unit 210f,
Ω: applied angular velocity, v: displacement velocity of the detection mass unit 210f

  The signal processing integrated circuit chip 204 obtains the displacement in the X direction generated by the Coriolis force as a change in capacitance between the detection mass 210f and the detection electrode 210d, and calculates the angular velocity. The displacement amount generated here is expressed by an equation similar to Equation 1, but is actually an equation that depends on the sealing pressure of the angular velocity detecting element chip 206, the frequency in the driving direction, and the frequency in the detection direction. . The description of the details of this equation is omitted. The signal processing integrated circuit chip 204 for electrically obtaining the change in capacitance will be described later.

  FIG. 4 is a top view showing an example of the second composite inertial sensor 103 (sensor module). Here, the Z positive direction in FIG. The second composite inertial sensor 103 includes a package 301, external electrodes 303, a signal processing integrated circuit chip 304, an acceleration detection element chip 305, an angular velocity detection element chip 306, a pad 307, and a bonding wire 308. Then, for example, the pad 307 and the angular velocity detecting element chip 306 are connected by wiring.

  FIG. 5 is a side view showing an example of the second composite inertial sensor 103. Here, the Y negative direction in FIG. The package 301 includes a package lid 302 omitted in FIG. 4, and the structure of the package 301 is the same as the structure of the package 201 shown in FIGS. Since the package 301 includes the acceleration detection element chip 305 and the angular velocity detection element chip 306, even if the package 301 is a single unit, its output is the output of two-axis acceleration and one axis of angular velocity, and the output of the three-axis detection module. Become.

  On the acceleration detection element chip 305, a first detection element 311 for detecting acceleration and a second detection element 312 are arranged having orthogonal detection axes. For this reason, the acceleration detection element chip 305 can detect biaxial acceleration. Note that the first detection element 311 and the second detection element 312 are each a portion surrounded by a broken line in FIG. The first detection element 311 is an element for detecting the acceleration in the Y direction in FIG. 4 and has the same structure as the first detection element 211, and thus the description is omitted.

  The second detection element 312 is an element for detecting acceleration in the Z direction in FIG. 4, and a spring mass system is constructed in which the detection mass portion 312c is suspended from the anchor portion 312a through the spring portion 312f. Note that, in FIG. 4, since the detection mass portion 312c is hidden by the out-of-plane electrode 312b, it is shown in FIG. Here, when a static linear acceleration is applied, a displacement according to Equation 1 occurs.

  In order to obtain this displacement as a change in capacitance, the second detection element 312 is provided with an out-of-plane electrode 312b in the Z direction of the acceleration detection element chip 305 as shown in FIG. Since a change in the gap between the detection mass portion 312c and the out-of-plane electrode 312b causes a change in the capacitance, the signal processing integrated circuit chip 204 electrically obtains this change in the capacitance and calculates the acceleration. This detailed configuration will be described later.

  Further, a detection element 310 for detecting an angular velocity is arranged on the angular velocity detection element chip 306 shown in FIG. The detection element 310 is a portion surrounded by a broken line in FIG. 4 and detects the angular velocity around the X axis in FIG. 4, and the spring mass in which the detection mass portion 310f is suspended from the anchor portion 310c through the spring portion 310g. A system is built. In FIG. 4, since the detection mass portion 310f is hidden by the out-of-plane electrode 310d, it is shown in FIG.

  Then, when the displacement speed generated by the vibration of the detection mass portion 310f in the Y direction is set to v, when an angular velocity Ω around the X axis is applied, a force according to Expression 2 is generated in the Z direction in FIG. In order to detect the displacement in the Z direction generated by the Coriolis force, the detection element 310 is provided with an out-of-plane electrode 310d as shown in FIG. The change in capacitance between the electrodes 310d is obtained, and the angular velocity is calculated.

  2 to 4 show an example in which two detection electrodes 211b and 210d and two out-of-plane electrodes 312b and 310d are provided for the detection mass portions 211c, 210f, 312c, and 310f, respectively. As long as a large change in capacitance is obtained, one electrode may be used.

  Next, an example of the signal processing integrated circuit chip 204 of the first composite inertial sensor 102 will be described with reference to FIG. The signal processing integrated circuit chip 204 is supplied with the power supplied to the sensor package unit 101 via the connector 110 adjusted to a predetermined voltage by the power supply regulator IC 105. Here, one power supply regulator IC 105 supplies power to the second composite inertial sensor 103 in addition to the first composite inertial sensor 102 through the same wiring 111 as shown in FIG.

  The voltage of the supplied power is further adjusted by an LSI regulator unit 502 in the signal processing integrated circuit chip 204, and is used as an analog reference voltage of the signal processing integrated circuit chip 204. The analog section reference voltage is, for example, an oscillator 503, a carrier generation section 504, a drive signal generation section 505, a drive side CV conversion section 508, a drive side ADC section 509, a detection side CV conversion section 513, a detection side ADC section 514, Y The signals are supplied to the side CV converter 516, the Y-side ADC 517, the X-side CV converter 518, the X-side ADC 519, the temperature sensor 522, and the carrier generator 524 as shown by the thick line in FIG. preferable.

  Note that the signal processing integrated circuit chip 204 of the first composite inertial sensor 102 does not include the LSI regulator unit 502, and even if power supplied from the power supply regulator IC 105 is directly supplied to each unit in the signal processing integrated circuit chip 204. Good.

  Hereinafter, signal processing for acceleration detection in the signal processing integrated circuit chip 204 will be described. The signal processing integrated circuit chip 204 uses the oscillator 503 to generate an AC signal having a frequency of about 100 KHz. The AC signal is adjusted to a predetermined voltage level by the carrier generation section 524 and applied to the detection mass section 211c of the acceleration detection element chip 205 through the pad 207 and the bonding wire 208. This AC signal is called a carrier signal.

  Since the carrier signal applied to the detection mass unit 211c is an AC signal, if the capacitance between the detection mass unit 211c and the detection electrodes 211b-1 and 211b-2 changes due to the application of acceleration, the detection electrode 211b- 1, there is a change in the alternating current of 211b-2. Assuming that the change in the alternating current is a change in the capacitance, the capacitance is converted into a voltage signal by the CV converter 516, and is converted into a digital signal through an ADC (Analog-Digital Converter) unit 517.

  Further, a carrier signal is also applied from the carrier generation unit 524 to the detection mass unit 212c of the acceleration detection element chip 205, and a change in the alternating current of the detection electrodes 212b-1 and 212b-2 is regarded as a change in capacitance. The capacitance is converted into a voltage signal by the CV converter 518, and is converted into a digital signal through the ADC 519. The digital signals converted by the ADC units 517 and 519 are input to the correction circuit 521.

  The correction content is stored in the memory 520 in advance, and the correction circuit 521 performs offset and sensitivity correction in accordance with the correction content of the memory 520, and performs temperature dependency compensation according to the output of the temperature sensor 522. The information of the detected acceleration is output to the outside of the first combined inertial sensor 102 through a digital communication circuit 523 such as SPI (Serial Peripheral Interface) communication.

  Next, signal processing for detecting angular velocity in the signal processing integrated circuit chip 204 will be described. To detect the angular velocity, it is necessary to vibrate the detection mass unit 210f at a constant frequency and amplitude. In order to realize this, the signal processing integrated circuit chip 204 uses the oscillator 503 to generate an AC signal serving as a drive signal for vibrating the detection mass unit 210f.

  In the example of FIG. 6, the oscillator 503 that is output to the carrier generation unit 524 for detecting acceleration is also used for generating an AC signal for detecting angular velocity, but is a separate body independent of the oscillator for detecting acceleration. It may be an oscillator. When AC signals having different frequencies are used for acceleration detection and angular velocity detection, a frequency divider or a multiplier (not shown) may be provided at the output of the oscillator 503 to generate each AC signal.

  The AC signal output from the oscillator 503 is amplified to a predetermined voltage by the drive signal generation unit 505, and further applied to the drive electrode 210b-2 of the angular velocity detection element chip 206 through the gain adjustment unit 506. The AC signal whose output from the gain adjustment unit 506 is inverted in phase by the phase inverter 507 is applied to the drive electrode 210b-1. The application of these AC signals generates an electrostatic force, and the detection mass unit 210f vibrates.

  In order to detect the amplitude and frequency of this vibration, the oscillator 503 generates an AC signal having a frequency of about several hundred KHz. This frequency may be the same as or different from the carrier signal for detecting the capacitance. If the frequencies are the same, the circuit configuration becomes simple, but signal coupling may occur. Therefore, it is preferable to use different frequencies.

  The AC signal output from the oscillator 503 is adjusted to a predetermined voltage level by the carrier generation unit 504, and is applied to the detection mass unit 210f of the angular velocity detection element chip 206 through the pad 207 and the bonding wire 208. This AC voltage signal is called a carrier signal. Since the carrier signal applied to the detection mass unit 210f is an AC signal, if the detection mass unit 210f is displaced, the capacitance between the detection mass unit 210f and the drive monitor electrodes 210a-1 and 210a-2 changes. , A change occurs in the alternating current of the drive monitor electrodes 210a-1 and 210a-2.

  Assuming that the change in the alternating current is a change in the capacitance, the capacitance is converted into a voltage signal by the CV converter 508 and sent to the synchronous detector 510 via the ADC 509. The synchronous detection unit 510 extracts two components, a phase difference between the driving vibration of the detection mass unit 210f and a predetermined frequency, and an amplitude component of the displacement of the detection mass unit 210f, and outputs the extracted phase difference to the frequency control unit 511. Then, the extracted amplitude component is output to amplitude control section 512.

  Frequency control section 511 outputs a control signal to oscillator 503 based on the phase difference between the drive vibration of detection mass section 210f and the predetermined frequency so that the frequency of the drive vibration matches the predetermined frequency. Further, amplitude control section 512 outputs a control signal to gain adjustment section 506 so as to maintain a predetermined drive amplitude of detection mass section 210f. By these two control signals, the drive vibration of the detection mass unit 210f maintains a constant amplitude and a constant frequency.

  When an angular velocity is applied in a state where the driving vibration of the detection mass portion 210f of the angular velocity detection element chip 206 is maintained, a displacement of the detection mass portion 210f with respect to the detection electrodes 210d-1 and 210d-2 occurs due to Coriolis force. This causes a change in the capacitance between the detection mass portion 210f and the detection electrodes 210d-1 and 210d-2. Since a carrier signal has been applied from the carrier generation unit 504 to the detection mass unit 210f, the capacitance is converted into a voltage signal by the CV conversion unit 513 and sent to the detection unit 515 through the ADC unit 514.

  The detection unit 515 extracts the amplitude component of the displacement of the detection mass unit 210f by the synchronous detection processing, and calculates the force applied to the detection mass unit 210f, that is, the Coriolis force. The calculated Coriolis force is a force proportional to the applied angular velocity as shown in Expression 2, and the other coefficients are constants, and thus may be referred to as the detected applied angular velocity. The detected applied angular velocity is subjected to offset / gain adjustment by the correction circuit 521 or temperature dependence compensation according to the output of the temperature sensor 522, and then to the outside of the first composite inertial sensor 102 through the digital communication circuit 523. Is output.

  By the way, when the drive amplitude increases and the speed in the drive direction also increases, the Coriolis force generated by the angular velocity also increases in proportion to this, as shown in Expression 2. Therefore, from the viewpoint of increasing the sensitivity (Scale Factor) of the sensor, it is desirable to maximize the drive amplitude. In order to obtain the maximum drive amplitude within a limited voltage range, it is preferable in terms of efficiency to drive at the resonance frequency of the detection mass unit 210f. Therefore, it is preferable that the frequency control unit 511 controls the drive signal to be at the resonance frequency (generally, substantially equal to the natural frequency) of the detection mass unit 210f.

  The first composite inertial sensor 102 may be a circuit that operates on a single power supply, or may be a circuit that operates on a power supply of a plurality of voltages. When the circuit operates with a single power supply, the power supply regulator IC 105 and the LSI regulator unit 502 may output one voltage as a power supply.

  In order to express the acceleration or angular velocity in the positive direction and the acceleration or angular velocity in the negative direction using one power supply voltage as analog signals, for example, an analog signal in the state where no acceleration or angular velocity is applied is half of the power supply voltage. It may be a voltage. The analog signal representing the positive direction may be a voltage larger than half the power supply voltage, and the analog signal representing the negative direction may be a voltage smaller than half the power supply voltage.

  The information on the acceleration and the angular velocity of the digital communication circuit 523 includes information on the positive direction and information on the negative direction. For example, based on the two's complement expression, the polarity with the positive direction being a positive value and the negative direction being a negative value is determined. May be included. Further, the digital communication circuit 523 may receive a data request from outside the first composite inertial sensor 102 and transmit data of acceleration or angular velocity information at the time of receiving the data request. In particular, a data request may be received from microcontroller 104 and data may be transmitted to microcontroller 104.

  Next, signal processing of the microcontroller 104 will be described. The microcontroller 104 calculates the total two-axis angular velocity output obtained from the first composite inertial sensor 102 and the second composite inertial sensor 103 and the three-axis acceleration output (however, the one-axis acceleration of the three axes is two composite axes). (Obtained from the inertial sensor), and the attitude of the sensor package unit 101 is calculated from the information.

  When the posture is calculated using the acceleration and the angular velocity, the microcontroller 104 calculates, for example, the initial posture using the acceleration sensor output and the inverse trigonometric function, and the subsequent posture change is a relative change obtained by time integration of the angular velocity. Is performed. It also implements a filtering technology that always uses the values of acceleration and angular velocity, such as the so-called Kalman Filter, to directly estimate the target's attitude, or to compensate for sensor errors that correspond to an application called a complementary filter. May be performed to perform signal processing for obtaining a posture.

  Regardless of the type of signal processing, acceleration for detecting the absolute posture is required. Therefore, it is important to improve the accuracy of the acceleration sensor in estimating the posture. Therefore, in this embodiment, each one axis of the two three-axis composite inertial sensors is used as a common detection axis. That is, in the example of FIG. 1, the first acceleration detection axis 108a of the first composite inertial sensor 102 and the third acceleration detection axis 106a of the second composite inertial sensor 103 are overlapped with detection axes (X (Axis), the first combined inertial sensor 102 and the second combined inertial sensor 103 are arranged.

  Then, the signal of the first acceleration detection axis 108a and the signal of the third acceleration detection axis 106a are combined, and the signal quality (SNR, Signal to Noise Ratio) calculated as the X-axis acceleration is improved. For this purpose, the microcontroller 104 calculates, for example, a difference between the signal of the first acceleration detection axis 108a and the signal of the third acceleration detection axis 106a. As shown in FIG. 7, this difference calculation is performed by converting the output of the first acceleration detection axis 108a and the output of the third acceleration detection axis 106a into a signal XG + and a signal XG-, and inverting the polarity of the signal XG- to 2 The two signals may be added and halved to obtain signal XG + '.

  For example, as shown in FIG. 9, a noise factor (common noise) common to the first acceleration detection axis 108a and the third acceleration detection axis 106a is in phase with the signal XG + and the signal XG- which are the respective sensor outputs. Appears (common mode noise). On the other hand, since the microcontroller 104 adds one of the signals of the axes having the opposite sensitivities and measuring the same physical quantity, the polarity of which is inverted, a signal in which the common noise is canceled is obtained as the signal XG + '.

  An example of the common noise in the present embodiment is that the power regulator IC 105 is common to the first composite inertial sensor 102 and the second composite inertial sensor 103, so that if the voltage output from the power regulator IC 105 fluctuates, The noise appears in the output of the first composite inertial sensor 102 and the output of the second composite inertial sensor 103.

  In the case of this voltage fluctuation, in FIG. 9, “Voltage” is a voltage of a single power supply, and when the voltage temporarily decreases, the voltage of the signal XG +, which is an analog signal, also decreases according to the power supply voltage. Since "0" of the signal XG-, which is an analog signal, is half of the power supply voltage, the voltage of the signal XG- changes so as to increase the difference from "0", as shown in FIG.

  Further, the influence of an external electromagnetic wave or the like generated according to the installation environment of the sensor package unit 101 also appears as common noise in the outputs of the first composite inertial sensor 102 and the second composite inertial sensor 103 whose physical distances are short. Canceling these common noises is suitable for improving the signal quality of the acceleration sensor, and is useful for improving the accuracy of the posture calculation.

  Further, as shown in FIG. 10, the output of the first composite inertial sensor 102 and the output of the second composite inertial sensor 103 are not limited to the power supply and the external electromagnetic wave, and the random number of the detection mass portion due to Brownian motion, for example. Thermal noise of a circuit related to displacement and detection is generated as uncorrelated noise. Even for such uncorrelated noise, the microcontroller 104 adds one of the signals of the axes measuring the same physical quantity having the opposite sensitivities by inverting the polarity and adding the signal component, and the noise component is doubled. √2 times, and the signal quality of the signal XG + 'is improved by √2 times (3 dB).

  In the present embodiment, the first acceleration detection axis 108a and the third acceleration detection axis 106a measure the same physical quantity (including the axis) having opposite sensitivities, but have the same sensitivity and common noise. Is output in the opposite polarity direction, or when there is uncorrelated noise with the same sensitivity, the process of adding and inverting the polarity shown in FIG. May be replaced by Further, the same signal processing may be performed on the temperature sensor 522 mounted on the first composite inertial sensor 102 shown in FIG. 6, and the same signal processing is performed on the temperature sensors of other composite inertial sensors. May be applied.

  Also, in the case of performing signal processing for detecting the orientation of an object by always using the output of an acceleration sensor and the output of an angular velocity sensor as filter inputs, such as a Kalman filter, the same physical quantity (including an axis) having the opposite sensitivity is measured. By inputting both outputs of the first acceleration detection axis 108a and the third acceleration detection axis 106a to the filter, the accuracy of posture detection can be improved.

  For example, an example in which a complementary filter which is a kind of the Kalman filter as shown in FIG. 8 is used will be described. Here, θGyro is the attitude calculated by the time integration of the angular velocity sensor, and θXG + and θXG- are the attitudes calculated by the inverse trigonometric function from the output of the acceleration sensor. This complementary filter estimates the time integration error of the angular velocity sensor and compensates for it.

  At this time, according to the configuration of the present embodiment, the signals (θGyro, θXG−) input to the complementary filter can be increased as shown in FIG. In the complementary filter, a plausible error of θGyro is estimated based on a plurality of input signals. Therefore, if independent signal components are included in θXG + and θXG−, the error estimation accuracy of the complementary filter can be improved.

  Note that the microcontroller 104 has a sample rate that is at least twice as fast as the band of the acceleration signal detected on each of the first acceleration detection axis 108a and the third acceleration detection axis 106a that measure the same physical quantity (including the axis). Then, data is read from each of the first combined inertial sensor 102 and the second combined inertial sensor 103. FIG. 11 shows, as an example, a frequency response graph when the acceleration signal detected on the third acceleration detection axis 106a has a band of 100 Hz. That is, the frequency of 100 Hz at which the response is reduced by at least -3 dB is set as the upper limit of the band of the signal detected on the third acceleration detection axis 106a.

  At least from DC to 100 Hz, which is this band, includes a signal component representing acceleration, common noise, and uncorrelated noise, and the sampling rate (readout speed, composite inertial sensor If the data request transmission interval is less than 200 Hz, the signal waveform of acceleration, signal noise of common noise, and uncorrelated noise may be distorted by the aliasing phenomenon, and the operation described above may not be obtained. There is. For this reason, it is desirable that the sampling rate be 200 Hz or more, that is, twice or more as fast as indicated by an arrow 701 in FIG.

  As described above, the signal quality improvement using the first acceleration detection axis 108a and the third acceleration detection axis 106a for measuring the same physical quantity (including the axis) having the opposite sensitivity obtained in the present embodiment is particularly new. It is not obtained by adding an additional acceleration detection axis, but the detection axis that is inevitably duplicated in a configuration using two 3-axis sensor modules that provide the function of an acceleration / angular velocity sensor by itself is used as an input for signal processing. May be used. As a result, accurate acceleration sensor output, that is, absolute posture detection, can be realized without adding special costs (hardware cost, development period, installation area).

  In the first embodiment, the example in which the first combined inertial sensor 102 includes the first detection element 211 and the second detection element 212 and has two detection axes has been described. An example of the first detection element 211 having an axis will be described. FIG. 12 is a top view illustrating an example of the composite inertial sensor according to the second embodiment. FIG. 13 is a side view illustrating an example of the composite inertial sensor according to the second embodiment. The description of the structure already described with reference to FIGS.

  The spring portion 211f has a degree of freedom in which the detection mass portion 211c can be displaced in both the X axis and the Y axis in FIG. 12, and the displacement when a static linear acceleration in the X direction in FIG. 12 is applied is detected. The displacement when the static linear acceleration in the Y direction in FIG. 12 is detected by the electrode 211e is detected by the detection electrode 211b. As a result, the first detection element 211 performs biaxial acceleration detection. Then, the first composite inertial sensor 102 of the sensor package unit 101 shown in FIG. 1 has the structure shown in FIGS.

  With this configuration, it is possible to realize a smaller size and a lower price such as a reduction in the area of the acceleration detection element chip 205 while utilizing the same advantages as the first embodiment.

  In the first embodiment, the example in which the first composite inertial sensor 102 and the second composite inertial sensor 103 are arranged as shown in FIG. 1 has been described. In the third embodiment, the first composite inertial sensor 402 and the second An example in which the composite inertial sensor 403 is arranged as shown in FIG. 14 will be described. FIG. 14 is a diagram illustrating an example of the inertial sensor according to the third embodiment. The inertial sensor according to the third embodiment includes a first composite inertial sensor 402, a second composite inertial sensor 403, a microcontroller 404, and a power regulator IC 405 in a sensor package unit 401. The power regulator IC 405 supplies power to the first composite inertial sensor 402 and the second composite inertial sensor 403.

  Here, the inertial sensor according to the third embodiment is different from the inertial sensor according to the first embodiment in that the first composite inertial sensor 402 and the second composite inertial sensor 403 are substantially rectangular parallelepipeds having the same shape. Although it is a composite inertial sensor having the same detection axis with respect to the surface and having the same physical and electrical specifications, the surface on which the first composite inertial sensor 402, the microcontroller 404, and the power supply regulator IC 405 are arranged (the XY plane) The second composite inertial sensor 403 is arranged on a step 411 (XZ plane) substantially perpendicular to ()).

  Therefore, for example, the first composite inertial sensor 402 includes a first acceleration detection axis 407a having acceleration sensitivity in the positive X direction in FIG. 14 and a second acceleration detection axis having acceleration sensitivity in the positive Y direction in FIG. 14 is provided with a first angular velocity detection axis 408 having angular velocity sensitivity in the positive direction (Yaw) around the Z axis in FIG. 14, whereas the second composite inertial sensor 403 is provided with a negative X direction in FIG. 14, a fourth acceleration detection axis 408b having an acceleration sensitivity in the positive Z direction in FIG. 14, and an angular velocity sensitivity in a positive direction (Roll) around the Y axis in FIG. The second angular velocity detection axis 409 will be provided.

  Accordingly, the inertial sensor shown in FIG. 14 can detect accelerations in the X, Y, and Z directions, can detect the angular velocities of Yew and Roll, and can also detect the positive X direction as in the example of the inertial sensor shown in FIG. And the acceleration in the negative X direction can be detected independently.

  This configuration has the following advantages as compared with the first embodiment. That is, by performing the difference calculation between the first acceleration detection axis 407a and the third acceleration detection axis 408a that measure the same physical quantity having opposite sensitivities, the effect of improving the signal quality shown in the first embodiment can be obtained. .

  Furthermore, since the first compound inertial sensor 402 and the second compound inertial sensor 403 are three-axis sensor modules having the same specifications, the amount of change and the sensitivity of common noise generated following the change of the power supply regulator IC 405 are reduced. In addition, it is expected that the temperature dependency (bias, sensitivity) has very similar characteristics between the two three-axis sensor modules. Since these are expected to be canceled by differential, an effect useful as the third embodiment can be obtained.

  In the first to third embodiments, an example in which two composite inertial sensors are used has been described. In the fourth embodiment, an example in which three composite inertial sensors are used will be described. FIG. 15 is a diagram illustrating an example of the inertial sensor according to the fourth embodiment. In the inertial sensor according to the fourth embodiment, a sensor package unit 101 includes a first composite inertial sensor 601, a second composite inertial sensor 602, a third composite inertial sensor 603, a microcontroller (not shown), and a power supply. It has a regulator IC 605. The power regulator IC 605 supplies power to the first combined inertial sensor 601, the second combined inertial sensor 602, and the third combined inertial sensor 603.

  Here, the substrate 610 is a double-sided substrate arranged so as to be on the XY plane in the sensor package unit 101, and the second composite inertial sensor 602 and the third composite inertial sensor 603 are mounted on the same surface of the substrate 610. The first composite inertial sensor 601 is mounted on the back side of the substrate 610 on which the second composite inertial sensor 602 and the third composite inertial sensor 603 are mounted. The first composite inertial sensor 601 is a composite inertial sensor having the same specifications as the third composite inertial sensor 603, that is, a sensor module.

  In this embodiment, as shown in FIG. 15, the first acceleration detection axis 604a of the first composite inertial sensor 601 and the second acceleration detection axis 605b of the second composite inertial sensor 602 have opposite sensitivities. It corresponds to an acceleration detection axis for measuring the same physical quantity. In addition, the second acceleration detection axis 604b of the first composite inertial sensor 601 and the second acceleration detection axis 606b of the third composite inertial sensor 603 correspond to acceleration detection axes for measuring the same physical quantity having opposite sensitivities. . In addition, the first acceleration detection axis 605a of the second composite inertial sensor 602 and the first acceleration detection axis 606a of the third composite inertial sensor 603 correspond to acceleration detection axes for measuring the same physical quantity having opposite sensitivities. .

  In this embodiment, since the power supply regulator IC 605 supplies a voltage to the composite inertial sensor relating to three axes, the effect of canceling common noise with respect to power supply fluctuation can be obtained for three-axis acceleration. The improvement of the signal quality by combining the acceleration detection axes for measuring the same physical quantity having the opposite sensitivities shown in the above can be obtained for the accelerations of the three axes.

  As described in the third embodiment, a step (not shown) is provided in the sensor package unit 101, and the first composite inertial sensor 601 and the third composite inertia are provided instead of the second composite inertial sensor 602. A composite inertial sensor having the same specifications as the sensor 603 may be mounted on the step. Thus, since the three composite inertial sensors have the same specifications, the effects described in the third embodiment can be obtained in three axes.

  Further, in order to obtain the same effect, the composite inertial sensor may have a structure of detecting two-axis angular velocity and detecting three-axis acceleration, for example. By using two 5-axis composite inertial sensors, a similar effect, that is, an improvement in signal quality by combining acceleration detection axes for measuring the same physical quantity having opposite sensitivities can be obtained for three-axis acceleration.

  In the first to fourth embodiments, the example in which the microcontrollers 104 and 404 are provided in the sensor package units 101 and 401 has been described. In the fifth embodiment, the example in which the microcontroller 1104 is provided outside the sensor package units 1010a and 1010b. explain. FIG. 16 is a diagram illustrating an example of the inertial sensor according to the fifth embodiment. Each of the sensor package units 1010a and 1010b is connected to a communication IC 1103 installed on a substrate 1102 via a communication bus 1101 connected to the connectors 1100a and 1100b.

  On the substrate 1102, the communication IC 1103 is connected to the microcontroller 1104 and the position information acquisition module 1106 via the communication line 1105. The microcontroller 1104 includes an MPU (Micro Processing Unit) having a higher calculation capability than the microcontrollers 104 and 404 of the first to fourth embodiments, and mainly includes an acceleration for measuring the same physical quantity in order to improve the signal quality described in the first embodiment. Execute signal processing using the detection axis. Thereby, even if the signal processing for the posture detection is a complicated procedure, it can be processed, and the advantages shown in the first embodiment can be continuously obtained.

  The position information acquisition module 1106 may be a module for a system that obtains absolute coordinates on the earth, such as a GPS (Global Positioning System) receiver. In this case, the microcontroller 1104 can correct the gravity that varies depending on the latitude on the earth, so that the accuracy of the posture detection can be improved. Note that the sensor package units 1010a and 1010b may be any of the sensor package units 101 and 401 described in the first to fourth embodiments.

  In the first to fifth embodiments, an example in which one composite inertial sensor has a plurality of detection axes has been described. In the sixth embodiment, an example in which one composite inertial sensor has one detection axis will be described. FIG. 17 is a diagram illustrating an example of the inertial sensor according to the sixth embodiment. The inertial sensor according to the sixth embodiment includes a first inertial sensor 1202, a second inertial sensor 1203, a microcontroller 1204, and a power regulator IC 1205 in a sensor package unit 1201.

  The first inertial sensor 1202 includes a first acceleration detection axis 1206 having an acceleration sensitivity in the positive X direction in FIG. 17, and the second inertial sensor 1203 has a second acceleration detection axis in the negative X direction in FIG. The acceleration detection axis 1207 is provided. The power supply IC 1205 supplies power to the first inertial sensor 1202 and the second inertial sensor 1203.

Even in such a configuration, it is possible to measure the inclination with one detection axis. That is, assuming that the acceleration output in the positive X direction is Xout, the inclination of one detection axis can be obtained by Sin ^-1 (Xout) although the value range is limited. Therefore, by applying the signal processing shown in the first embodiment, it is possible to combine two outputs having the opposite sensitivities and measuring the same angular velocity, and calculate the inclination with high accuracy.

  When the inertial sensor of this embodiment is an angular velocity sensor, although the initial inclination cannot be obtained, the two outputs for measuring the same angular velocity having the opposite sensitivity can be obtained by applying the signal processing shown in the first embodiment. By combining, the relative inclination can be calculated with high accuracy.

  In the first to sixth embodiments, the example of the inertial sensor has been described. In the seventh embodiment, an application example of the inertial sensor will be described. FIG. 18 is a diagram illustrating an example of an automobile 1301. An automobile 1301 according to the seventh embodiment includes a first sensor package unit 1302, a second sensor package unit 1303, and a communication path 1304 connecting the first sensor package unit 1302, the second sensor package unit 1303, and the like.

  The first sensor package unit 1302 includes the first composite inertial sensor 102, the microcontroller 104, and the power supply regulator IC 105 shown in FIG. 1, and the first composite inertial sensor 102 of the first sensor package unit 1302 is A first acceleration detection axis 108a having acceleration sensitivity in the positive X direction of FIG. 1, a second acceleration detection axis 108b having acceleration sensitivity in the positive Y direction of FIG. 1, and a positive direction around the Z axis of FIG. Yaw) is provided with a first angular velocity detection axis 109 having angular velocity sensitivity.

  The second sensor package unit 1303 is an inertial sensor that is installed in the automobile 1301 and is used for purposes other than the detection of the attitude of the automobile. In addition, at least one acceleration detection axis of the inertial sensor of the second sensor package unit 1303 includes an inertial sensor that measures the same physical quantity having sensitivity opposite to that of the first acceleration detection axis 108a or the second acceleration detection axis 108b. .

  Then, the microcontroller 104 of the first sensor package unit 1302 obtains the acceleration detected from the second sensor package unit 1303 via the communication path 1304, and obtains the acceleration detected in the first sensor package unit 1302. Combining improves signal quality. The obtained acceleration may be used for controlling driving of the automobile 1301.

  With such a configuration, the signal quality can be improved by using an inertial sensor previously installed in the vehicle. This is suitable because it is possible to realize, at low cost, applications in which vehicle attitude detection is important, such as automatic driving and a safe driving support system. In addition, the present embodiment can be applied to a device other than an automobile, such as a robot or a drone, that performs posture control using an inertial sensor.

Reference Signs List 101 sensor package unit 102 first compound inertial sensor 103 second compound inertial sensor 104 microcontroller 105 power supply regulator IC
106a Third acceleration detection axis 108a First acceleration detection axis 111 Wiring

Claims (9)

A sensor device including a plurality of physical sensors that output detection results on a plurality of detection axes, and a sensor package that calculates the acceleration and angular velocity of a measurement target by integrating the output of the sensor device over time ,
Each of the plurality of detection axes of the acceleration and the angular velocity has a detection direction along the detection axis,
A first physical sensor among the plurality of physical sensors has a first detection axis among the plurality of detection axes of the first physical sensor,
A second physical sensor among the plurality of physical sensors has a second detection axis among the plurality of detection axes of the second physical sensor,
The first physical sensor is configured such that the first detection axis and the second detection axis overlap, and a detection direction of the first detection axis and a detection direction of the second detection axis are opposite to each other. And the second physical sensor are arranged ,
A controller to which a signal indicating acceleration detected from the first detection axis and the second detection axis is input;
The sensor package according to claim 1, wherein the controller has a complementary filter for estimating an error occurring in the first physical sensor and the second physical sensor from a signal indicating the acceleration . The sensor package according to claim 1, wherein:
The first physical sensor is a first three-axis sensor module having two detection axes for detecting acceleration including the first detection axis and one detection axis for detecting angular velocity,
The second physical sensor is a second three-axis sensor module having two detection axes for detecting acceleration including the second detection axis and one detection axis for detecting angular velocity. Sensor package . The sensor package according to claim 2 , wherein
A sensor package , wherein a common power is supplied to the first physical sensor and the second physical sensor. The sensor package according to claim 2, wherein
The first physical sensor further includes a third detection axis orthogonal to the first detection axis among a plurality of detection axes of the first physical sensor,
The second physical sensor further includes, among the plurality of detection axes of the second physical sensor, a fourth detection axis orthogonal to the second detection axis,
Furthermore, the first physical sensor and the second physical sensor are arranged so that the third detection axis and the fourth detection axis are orthogonal to each other, and the first detection axis and the third detection axis sensor package characterized by comprising a triaxial physical sensor by said fourth detection axis. The sensor package according to claim 4, wherein
The first physical sensor includes:
A fifth detection axis that is orthogonal to both the first detection axis and the third detection axis;
Detecting acceleration with the first detection axis and the third detection axis;
Detecting an angular velocity with the fifth detection axis;
The second physical sensor includes:
Further comprising a sixth detection axis orthogonal to both the second detection axis and the fourth detection axis;
Detecting acceleration with the second detection axis and the fourth detection axis;
A sensor package, wherein an angular velocity is detected by the sixth detection axis. The sensor package according to claim 2, wherein
A first substrate and a second substrate that are orthogonal to each other;
The first physical sensor and the second physical sensor have the same shape,
The first surface of the first physical sensor and the second surface of the second physical sensor have the same shape,
A third surface of the first physical sensor orthogonal to the first surface and a fourth surface of the second physical sensor orthogonal to the second surface have the same shape,
The first surface is in contact with the first substrate, the second surface is in contact with the second substrate, the first detection axis passing through the third surface, and the fourth surface The first physical sensor and the second physical axis are arranged such that the second detection axes passing therethrough overlap, and the detection direction of the first detection axis and the detection direction of the second detection axis are opposite. A sensor package in which physical sensors are arranged. The sensor package according to claim 2, wherein
Has a front and back double-sided board,
The first physical sensor and the second physical sensor have the same shape,
The first surface of the first physical sensor and the second surface of the second physical sensor have the same shape,
The third surface of the first physical sensor and the fourth surface of the second physical sensor have the same shape,
The first detection axis passing through the third surface, wherein the first surface contacts the front surface of the double-sided substrate, the second surface contacts the back surface of the double-sided substrate, and the fourth surface. The first physical sensor and the second physical axis are arranged such that the second detection axes passing therethrough overlap, and the detection direction of the first detection axis and the detection direction of the second detection axis are opposite. A sensor package in which physical sensors are arranged. The sensor package according to claim 2,
The sample rate at which the detection result is read from each of the physical sensors is
A sensor package, which is at least twice the signal band of the physical sensor. An autonomous driving vehicle comprising the sensor device according to claim 1,
The first detection axis is a detection axis for detecting acceleration,
The second detection axis is a detection axis for detecting acceleration,
Combining the detection result of the acceleration on the first detection axis with the detection result of the acceleration on the second detection axis to obtain a result of the acceleration on the first detection axis;
An automatic driving vehicle, wherein driving is controlled using a result of acceleration on the first detection axis.

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