JP5396936B2 - Vehicle stabilizer system - Google Patents

Description

  The present invention relates to a vehicle stabilizer system capable of changing a torsional reaction force generated by a pair of torsion bars by operation of an actuator.

  In recent years, a vehicle stabilizer system as described in the following patent document, specifically, a system that controllably generates a torsional reaction force of a stabilizer bar constituted by a pair of torsion bars has been studied, Already put into practical use.

JP 2006-347406 A

  In the system described in the above-mentioned patent document, the amount of roll that reduces the amount of roll generated by turning the torsional reaction force of the pair of torsion bars due to turning of the vehicle by controlling the relative rotation amount of the pair of torsion bars. It is possible to execute roll amount reduction control that acts as a reduction force. In recent years, it has been studied to execute roll vibration damping control in which the torsional reaction force acts as a roll vibration damping force that attenuates the roll vibration of the vehicle body. A system capable of executing the two controls of the roll amount reduction control and the roll vibration damping control is still under development, and there remains much room for improvement in the control method of the two controls. Therefore, it is possible to improve the practicality of the system by making various improvements. This invention is made | formed in view of such a situation, and makes it a subject to provide a highly practical vehicle stabilizer system.

  In order to solve the above-described problems, the vehicle stabilizer system of the present invention can change the torsional reaction force of the pair of torsion bars by rotating the pair of torsion bars and the pair of torsion bars relative to each other. The control relative rotation amount, which is the relative rotation amount of the pair of torsion bars from the set reference relative rotation position, is used as an index for indicating the actual relative rotation amount of the pair of torsion bars. , A stabilizer system that controls the torsional reaction force by controlling the actuator so that the control relative rotation amount becomes the target relative rotation amount, the reference relative rotation position for executing the roll amount reduction control, and the roll The reference relative rotational position for executing the vibration damping control is set based on different rules.

  Since the roll amount reduction control is a control for reducing the roll amount of the vehicle body caused by the turning of the vehicle, it is executed exclusively when the vehicle turns. When the vehicle turns, the stabilizer bar constituted by a pair of torsion bars is generally twisted in one direction, so there are few problems even if the actuator is controlled based on the state where the stabilizer bar is twisted to some extent. On the other hand, roll vibration damping control may be performed not only when the vehicle is turning but also when the vehicle is traveling straight. When the vehicle is traveling straight, the actuator is controlled based on the state that the stabilizer bar is twisted to some extent. It is not desirable to do so. In the stabilizer system of the present invention, the reference relative rotational position can be set based on different rules at the start time of the roll amount reduction control and the start time of the roll vibration damping control. According to this system, it is possible to set a reference relative rotational position suitable for each control. By having such an advantage, the stabilizer system of the present invention becomes highly practical.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

In each of the following items, the combination of items (1) to (4), (7), (8) corresponds to claim 1 , and claims (9), (11 ) And (12) are added with the technical features described in claim 2 , and the technical features described in (13) are added to claim 1 in claim 3. to any one (14) technically claim 4 which features were added according to the preceding claims 3 to claims 1 any one of claims 4 (15) according to claim The addition of technical features corresponds to claim 5 respectively.

(1) A pair of left and right wheels that are provided corresponding to the left and right wheels, each extending in the vehicle width direction, and each tip portion being connected to a wheel holding portion that holds a corresponding one of the left and right wheels. A torsion bar,
An actuator capable of changing the torsional reaction force generated by the pair of torsion bars by holding the pair of torsion bars so as to be rotatable relative to each other and rotating the pair of torsion bars relative to each other. When,
As an indicator of the actual relative rotation amount of the pair of torsion bars, a control relative rotation amount that is a relative rotation amount from a set reference relative rotation position is used, and the control relative rotation amount is a target relative rotation amount. A vehicle stabilizer system comprising: a control device that controls a torsional reaction force generated by the pair of torsion bars by controlling the actuator to have a rotation amount;
The control device is
A roll vibration damping control execution unit for performing roll vibration damping control for controlling the torsional reaction force so that at least a part thereof is a roll vibration damping force for damping the roll vibration of the vehicle body;
A roll amount reduction control execution unit that executes roll amount reduction control for controlling the torsional reaction force so that at least a part thereof becomes a roll amount reduction force for reducing the roll amount generated due to turning of the vehicle. When,
A vehicle stabilizer system comprising: a reference relative rotation position setting unit that sets the reference relative rotation position based on different rules at a start time of the roll vibration damping control and a start time of the roll amount reduction control.

  Since the roll amount reduction control is a control that causes the torsional reaction force to act as a roll amount reduction force for reducing the roll amount of the vehicle body caused by the turning of the vehicle, it is executed exclusively when the vehicle turns. During one turn of the vehicle, a stabilizer bar constituted by a pair of torsion bars is twisted in approximately one direction in order to reduce the roll amount of the vehicle body. For this reason, there are few problems even if the actuator is controlled based on the state in which the stabilizer bar is twisted to some extent. That is, when the relative rotation position of the pair of torsion bars in the state where the pair of torsion bars are assumed not to rotate relative to each other is defined as the neutral relative rotation position, the reference for executing the roll amount reduction control There are few problems even if the relative rotational position is set to a position deviated to some extent from the neutral relative rotational position. On the other hand, the roll vibration damping control may be executed not only when the vehicle turns but also when the vehicle goes straight. Since the relative rotational position of the pair of torsion bars when the vehicle is stationary on a horizontal and flat road surface is assumed to be the neutral relative rotational position, the reference relative rotational position is neutral relative when the vehicle is traveling straight. If it is set to a position that deviates to some extent from the rotational position, roll vibration damping control may be executed with reference to a state in which the vehicle is tilted left and right. Thus, it is not desirable to set the reference relative rotational positions of two different controls in the same way.

  In view of the above, the vehicle stabilizer system described in this section sets the reference relative rotational position based on different rules at the start time of the roll amount reduction control and the start time of the roll vibration damping control. It is possible to do. Therefore, according to the stabilizer system described in this section, it is possible to set a reference relative rotational position suitable for each control, and the stabilizer system becomes highly practical.

  The “reference relative rotation position setting unit” described in this section is based on different rules for the reference relative rotation position for executing the roll amount reduction control and the reference relative rotation position for executing the roll vibration damping control. The reference relative rotational position for executing the roll amount reduction control and the reference relative rotational position for executing the roll vibration damping control may be set at the same position. That is, as a result of setting the reference relative rotation position of each control based on different rules, the two reference relative rotation positions may be the same position.

(2) When the relative rotational position of the pair of torsion bars in the state where the pair of torsion bars is assumed not to rotate relative to each other is defined as a neutral relative rotational position,
The vehicle according to (1), wherein the control device includes a target relative rotation amount determination unit that determines a relative rotation amount from the neutral relative rotation position corresponding to the torsional reaction force to be generated as the target relative rotation amount. Stabilizer system.

  The “neutral relative rotational position” described in this section can be defined as the relative rotational position of a pair of torsion bars in a state where it is assumed that a stabilizer bar constituted by a pair of torsion bars is not twisted. It is. Each of the pair of torsion bars includes, for example, a shaft portion that extends in the vehicle width direction and an arm portion that extends continuously across the shaft portion and intersects the shaft portion. In this case, the “neutral relative rotational position” can be defined as the relative rotational position of the pair of shaft portions in a state where the pair of arm portions are parallel from the viewpoint from the side of the vehicle.

(3) A component that constitutes the target relative rotation amount, and when the component for the roll amount reduction control is defined as a roll amount reduction component,
The target relative rotation amount determination unit is
The vehicle stabilizer system according to item (2), configured to determine the roll amount reduction component according to a value of a roll moment index that indexes a roll moment received by a vehicle body.

  According to the stabilizer system described in this section, the roll amount of the vehicle body can be appropriately reduced. The “roll moment index” described in this section is a parameter that directly or indirectly represents the magnitude of the roll moment received by the vehicle body. Specifically, for example, the steering of the vehicle including the roll moment itself is used. Various factors such as an angle, a vehicle traveling speed, a lateral acceleration generated in the vehicle body, and a yaw rate of the vehicle correspond to the roll moment index.

(4) The reference relative rotational position setting unit is
When the roll amount reduction control is started at the reference relative rotation position, the control relative rotation amount at that time becomes equal to the roll amount reduction component determined by the target relative rotation amount determination unit at that time. The vehicle stabilizer system according to (3), configured to be set as described above.

  In the system described in this section, the reference relative rotational position for executing the roll amount reduction control is specifically limited. In a stabilizer system that controls the actuator so that the control relative rotation amount becomes the target relative rotation amount, if the difference between the control relative rotation amount at the start of control and the target relative rotation amount at that time is large, the control is performed. The amount of operation of the actuator at the start time becomes relatively large, and the actuator operates suddenly and greatly, and there is a possibility that an impact may occur with the rapid operation. On the other hand, if the control relative rotation amount at the control start time is the target relative rotation amount at that time, the actuator operation amount at the control start time is zero. Therefore, according to the system described in this section, it is not necessary to operate the actuator at the start of the roll amount reduction control, and it is possible to suppress the rapid operation of the actuator at the start of the roll amount reduction control.

  (5) The roll amount reduction control execution unit is configured to start execution of the roll amount reduction control when the value of the roll moment index exceeds a roll amount reduction control start threshold (3) or The vehicle stabilizer system according to (4).

  (6) The roll amount reduction control execution unit is configured to end the execution of the roll amount reduction control when the value of the roll moment index does not exceed the roll amount reduction control end threshold ( The vehicle stabilizer system according to item 5)

  In the system described in the above two items, the start time and the end time of execution of the roll amount reduction control are specifically limited. When the value of the roll moment index is small, there is little need to generate a roll amount reducing force, and therefore a control dead zone is provided in the roll amount reduction control. In the system described in the former section, the roll amount reduction component at the start of the roll amount reduction control has a magnitude corresponding to the roll amount reduction control start threshold value, and thus has a certain value. For this reason, if the relative rotation amount for control at the start of control becomes a small value, the actuator may operate rapidly at the start of control. Therefore, in the system described in the former section, the effect of setting the reference relative rotation position in the roll amount reduction control so that the control relative rotation amount at the start of control becomes equal to the roll amount reduction component at that time. Is fully utilized.

(7) When the component constituting the target relative rotation amount and the component for the roll vibration damping control is defined as a roll vibration damping component,
The target relative rotation amount determination unit is
The vehicle stabilizer according to any one of (2) to (6), wherein the roll vibration damping component is determined in accordance with a value of a roll speed index that indicates a speed of roll vibration of the vehicle body. system.

  According to the stabilizer system described in this section, it is possible to appropriately attenuate the roll vibration of the vehicle body. The “roll speed index” described in this section is a parameter that directly or indirectly represents the roll speed of the vehicle body. Specifically, for example, the spring top on the left wheel side and the spring top on the right wheel side It may be derived from the relative displacement speed, and is derived from the speed difference between the relative speed between the spring upper part and the unsprung part on the left wheel side and the relative speed between the spring upper part and the unsprung part on the right wheel side. Also good.

(8) The reference relative rotational position setting unit is
When the roll vibration attenuation control is started at the reference relative rotation position, the control relative rotation amount at that time becomes smaller than the roll vibration attenuation component determined by the target relative rotation amount determination unit at that time. The vehicle stabilizer system according to (7), configured to be set as follows.

  When the two controls are not executed, the actual relative rotational position of the pair of torsion bars is often near the neutral relative rotational position. For this reason, the reference relative rotation position in the roll vibration damping control is set to the same rule as in the roll amount reduction control, that is, the control relative rotation amount at the start of control becomes equal to the roll vibration damping component at that time. If set according to the rule, the reference relative rotational position in the roll vibration damping control is a position obtained by relatively rotating the pair of roll vibration damping components of the roll vibration damping component at the control start time from the actual relative rotational position. The position is shifted to some extent from the rotational position. That is, roll vibration damping control is executed based on a state in which a stabilizer bar constituted by a pair of torsion bars is twisted to some extent. Unlike the roll amount reduction control, the roll vibration damping control may be executed when the vehicle is traveling straight, and when the vehicle is traveling straight, the reference relative rotational position is set to a position that is somewhat deviated from the neutral relative rotational position. The roll vibration damping control may be executed based on the state where the vehicle is tilted left and right. Therefore, in the system described in this section, the reference relative rotational position in the roll vibration damping control is based on a rule such that the control relative rotational amount at the start of control is smaller than the roll vibration damping component at that time. It is possible to set the reference relative rotational position in the roll vibration damping control at a position that is set and does not deviate so much from the neutral relative rotational position.

  The concept of “being less than the roll vibration damping component” described in this section is a concept including the fact that it is less than the roll vibration damping component and becomes zero. That is, the “reference relative rotation position setting unit” described in this section sets the reference relative rotation position so that the relative rotation amount for control at that time becomes 0 at the start time of the roll vibration damping control. It is good.

  (9) The roll vibration damping control execution unit is configured to start execution of the roll vibration damping control when a value of the roll speed index exceeds a roll vibration damping control start threshold value, The vehicle stabilizer system according to item (8).

  (10) The roll vibration attenuation control execution unit is configured to end the execution of the roll vibration attenuation control when a state in which the value of the roll speed index does not exceed the roll vibration attenuation control end threshold continues for a set time. The vehicle stabilizer system according to (9).

  In the system described in the above two items, the start and end of execution of roll vibration damping control are specifically limited. When the value of the roll speed index is small, the necessity of generating the roll vibration damping force is small, so a control dead zone is provided in the roll vibration damping control.

(11) A component constituting the target relative rotation amount, wherein the component for the roll amount reduction control is defined as a roll amount reduction component.
The target relative rotation amount determination unit is
The roll amount reduction component is configured to be determined according to a value of a roll moment index that indicates a roll moment received by the vehicle body,
The roll amount reduction control execution unit is configured to start execution of the roll amount reduction control when a value of the roll moment index exceeds a roll amount reduction control start threshold,
The roll vibration damping control start threshold is
The roll vibration damping component determined when the roll speed index value exceeds the roll vibration damping control start threshold is determined when the roll moment index value exceeds the roll amount reduction control start threshold. The vehicle stabilizer system according to item (9) or (10), wherein the vehicle stabilizer system is set to be greater than the roll amount reducing component.

  When a control dead zone is provided for each of the roll amount reduction control and the roll vibration attenuation control, the roll vibration occurrence frequency is higher than the vehicle turn occurrence frequency. Therefore, the control dead zone of the roll vibration attenuation control is the roll amount reduction control. It is often set wider than the control dead zone. That is, the roll vibration attenuation component at the start of roll vibration attenuation control is larger than the roll amount reduction component at the start of roll amount reduction control. For this reason, for example, if the reference relative rotation position in the roll vibration damping control is set based on the same rule as the roll amount reduction control, the reference relative rotation position is set to be considerably shifted from the neutral relative rotation position. Become. Therefore, in the system described in this section, the reference relative rotation position in the roll vibration damping control is set to a rule different from that of the roll amount reduction control, that is, the control relative rotation amount at the start of control is the roll vibration at that time. The effect of setting based on a rule such that the amount is less than the attenuation component is fully utilized.

(12) The reference relative rotational position setting unit is
When the roll amount reduction control is started at the reference relative rotation position, the control relative rotation amount at that time becomes equal to the roll amount reduction component determined by the target relative rotation amount determination unit at that time. And set
The vehicle according to (11), wherein the reference relative rotation position is set to the reference relative rotation position set in the previous roll amount reduction control at the start of the roll vibration damping control. Stabilizer system.

When the control dead zone of the roll vibration attenuation control is set wider than the control dead zone of the roll amount reduction control, as described above, the roll vibration attenuation component at the start of the roll vibration attenuation control is the same as that at the start of the roll amount reduction control. More than the roll amount reducing component. That is, in the system described in this section, the reference relative-rotation position of the roll amount reduction control, the control relative rotation of the control start point on the roll amount reducing component equally by ing UNA rules at that time based has set, the reference relative-rotation position of the roll-vibration damping control, a control relative rotation of the control start time is set based on the rules Una by that of less than rolling vibration damping component at that time ing. Therefore, according to the system described in this section, it is possible to suppress the rapid operation of the actuator at the start of the roll amount reduction control and to execute the roll vibration damping control based on the state in which the vehicle is substantially horizontal. .

(13) The reference relative rotational position setting unit is
The reference relative rotation position is configured to set the relative rotation amount for control at that time to be 0 at the start time of the roll vibration damping control. (1) to (11) The vehicle stabilizer system as described in any one.

  In the system described in this section, the relative rotation amount from the reference relative rotation position becomes zero at the start of the roll vibration damping control. That is, the “reference relative rotation position setting unit” described in this section uses the reference relative rotation position as the actual relative rotation position of the pair of torsion bars at the start of the roll vibration damping control. It is set to. Since the actual relative rotational position of the pair of torsion bars at the start of control is substantially at the neutral relative rotational position, according to the system described in this section, the roll vibration is moved to a position where there is little deviation from the neutral relative rotational position. It becomes possible to set the reference relative rotational position in the attenuation control.

(14) The roll vibration attenuation control execution unit is configured to be able to execute the roll vibration attenuation control in parallel with the roll amount reduction control,
When the execution of the roll amount reduction control is already started, the reference relative rotation position setting unit sets the reference relative rotation position to the roll amount reduction control even if execution of the roll vibration damping control is started. The vehicle stabilizer system according to any one of items (1) to (13), wherein the vehicle is maintained at the reference relative rotational position set at the start time of the item (1).

(15) The roll amount reduction control execution unit is configured to be able to execute the roll amount reduction control in parallel with the roll vibration damping control,
When the execution of the roll vibration damping control has already started, the reference relative rotational position setting unit sets the reference relative rotational position to the roll vibration damping control even when the roll amount reduction control is started. The vehicle stabilizer system according to any one of items (1) to (14), wherein the vehicle is maintained at the reference relative rotational position set at a starting time of (1).

  If the reference relative rotation position is changed when each control is executed, the control relative rotation amount may change abruptly, causing the actuator to operate rapidly. In the system described in the above two sections, the reference relative rotational position is not changed while each control is being executed, and it is possible to suppress a rapid operation of the actuator during the control. Become.

(16) A component that defines the target relative rotation amount by defining a relative rotation position of the pair of torsion bars in a state where the pair of torsion bars are assumed not to rotate relative to each other as a neutral relative rotation position. When the component for the roll amount reduction control is defined as a roll amount reduction component, and the component for the roll vibration damping control is defined as a roll vibration damping component, respectively,
The control device is
A determining unit that determines a relative rotation amount from the neutral relative rotation position corresponding to the torsional reaction force to be generated as the target relative rotation amount, wherein the roll amount reduction control and the roll vibration damping control are performed in parallel; The roll amount reduction component according to the roll moment index value indicating the roll moment received by the vehicle body, and the roll vibration damping according to the roll speed index value indicating the roll vibration speed of the vehicle body. Item (14) or (15) has a target relative rotation amount determination unit that determines each component and determines the target relative rotation amount by adding the determined roll amount reduction component and the roll vibration damping component. The vehicle stabilizer system described in the item).

  In the system described in this section, the target relative rotation amount when the two controls are executed in parallel is specifically limited. According to the system described in this section, it is possible to appropriately execute two controls in parallel.

(17) Each of the pair of torsion bars extends in the vehicle width direction, extends continuously across the shaft portion and intersects the shaft portion, and the left and right wheels An arm portion connected to a wheel holding portion for holding a corresponding one,
The vehicle stabilizer system according to any one of (1) to (16), wherein the actuator relatively rotates a shaft portion of the pair of torsion bars.

  In the system described in this section, the configuration of the torsion bar and the actuator is specifically limited. According to the system described in this section, the torsional reaction force generated by the pair of torsion bars can be changed efficiently. The torsion bar may be a member in which the shaft portion and the arm portion are separate members, and may be combined, or may be integrally formed.

  (18) The actuator includes an electromagnetic motor, a speed reducer that decelerates rotation of the electromagnetic motor, and a housing that holds the electromagnetic motor and the speed reducer, and one shaft of the pair of torsion bars The vehicle stabilizer system according to (17), wherein a portion is connected to the housing in a relatively non-rotatable manner, and the other shaft portion is connected to the output portion of the speed reducer in a relatively non-rotatable manner.

  In the system described in this section, the structure of the actuator and the connection and arrangement relationship between the actuator and the torsion bar are specifically limited. The mechanism of the “reduction gear” described in this section is not particularly limited. For example, it may be called a harmonic gear mechanism (“harmonic drive (registered trademark) mechanism”, “strain wave gearing mechanism”, etc.). It is possible to employ speed reducers having various mechanisms such as a hypocycloid speed reducing mechanism. Considering the miniaturization of the electromagnetic motor, it is desirable that the reduction ratio of the speed reducer is relatively large (meaning that the operation amount of the actuator is small relative to the operation amount of the electromagnetic motor). It is desirable to use a harmonic gear mechanism.

  (19) The vehicle stabilizer system according to (18), wherein the reduction gear has a structure in which a reduction ratio thereof is 1/100 or less.

  If the actuator employs a reduction gear having a relatively large reduction ratio, the actuator is hardly moved by an external input. For this reason, when the roll moment index and the roll speed index are small, that is, when the respective controls are not executed, the actual relative rotational position of the pair of torsion bars is easily maintained at the neutral relative rotational position. Therefore, the system described in this section has the effect of setting the reference relative rotational position in the roll vibration damping control so that the control relative rotational amount at the start of control is smaller than the roll vibration damping component at that time. It is fully utilized.

It is a schematic diagram which shows the whole structure of the stabilizer system for vehicles which is a claimable invention. It is a schematic diagram which shows the stabilizer apparatus and suspension apparatus with which the vehicle stabilizer system of FIG. 1 is provided from the viewpoint from the vehicle upper side. It is a schematic diagram which shows the stabilizer apparatus and suspension apparatus with which the stabilizer system for vehicles of FIG. 1 is provided from the viewpoint from the vehicle front. It is a schematic sectional drawing which shows the actuator with which a stabilizer apparatus is provided. FIG. 2 is a circuit diagram in a state where an inverter and an electromagnetic motor included in the vehicle suspension system of FIG. 1 are connected. It is a table | surface which shows the switching state of the switching element by the inverter of FIG. 5 in each operation mode of an electromagnetic motor. 6 is a chart schematically showing changes in the actual lateral acceleration, roll amount reduction component, actual motor rotation angle, and control motor rotation angle with time in the initial turning of the vehicle. 6 is a chart schematically showing changes in roll speed, roll vibration attenuation component, actual motor rotation angle, and control motor rotation angle with time when roll vibration occurs. It is a flowchart which shows a stabilizer apparatus control program. It is a flowchart which shows the roll amount reduction component determination subroutine performed in a stabilizer apparatus control program. It is a flowchart which shows the roll vibration damping component determination subroutine performed in a stabilizer apparatus control program. It is a block diagram which shows the function of the control apparatus which manages control of a stabilizer system. It is a chart which shows roughly change with time passage of roll speed at the time of roll vibration generation in a modification, roll vibration attenuation component, real motor rotation angle, and control motor rotation angle.

  Hereinafter, embodiments and modifications of the claimable invention will be described in detail with reference to the drawings. In addition to the embodiments described below, the present invention can be claimed in various aspects including various modifications and improvements based on the knowledge of those skilled in the art, including the aspects described in the above [Aspect of the Invention] section. Can be implemented.

<Configuration of vehicle stabilizer system>
i) Overall Configuration of Stabilizer System FIG. 1 schematically shows a vehicle stabilizer system 10 according to this embodiment. The stabilizer system 10 includes a pair of stabilizer devices 14 disposed on the front wheel side and the rear wheel side of the vehicle. Each of the stabilizer devices 14 includes a stabilizer bar 20 connected to a suspension arm (see FIGS. 2 and 3) as a wheel holding member that holds the left and right wheels 16 at both ends. The stabilizer bar 20 includes a stabilizer bar member 22 as a pair of torsion bars into which the stabilizer bar 20 is divided. The pair of stabilizer bar members 22 are connected by an actuator 26 so as to be relatively rotatable.

ii) Configuration of Suspension Device A vehicle on which the system 10 is mounted is provided with four suspension devices corresponding to the wheels 16. The suspension device for the front wheel that is the steered wheel and the suspension device for the rear wheel that is the non-steered wheel can be regarded as substantially the same configuration except for the mechanism that enables the wheel to steer, The wheel suspension device will be described as a representative. As shown in FIGS. 2 and 3, the suspension device 30 is of an independent suspension type and is a multi-link type suspension device. The suspension device 30 includes a first upper arm 32, a second upper arm 34, a first lower arm 36, a second lower arm 38, and a toe control arm 40, each of which is a suspension arm. One end of each of the five arms 32, 34, 36, 38, 40 is rotatably connected to the vehicle body, and the other end is rotatable to an axle carrier 42 that rotatably holds the wheel 16. It is connected. With these five arms 32, 34, 36, 38, and 40, the axle carrier 42 can move up and down so as to draw a substantially constant locus with respect to the vehicle body. In addition, the suspension device 30 includes a coil spring 44 and a hydraulic shock absorber 46, which respectively include a mount portion 48 provided on a tire housing, which is a component of the spring upper portion, and a spring lower portion. They are arranged in parallel with each other between the second lower arm 38 which is one component. That is, the suspension device 30 elastically supports the sprung portion and the unsprung portion together, and generates a damping force against vibration associated with the approach and separation.

iii) Structure of Stabilizer Device As shown in FIGS. 2 and 3, each stabilizer bar member 22 of the stabilizer device 14 has a shaft portion 50 extending generally in the vehicle width direction, and is integrally formed with the shaft portion 50 so as to intersect therewith. It can be divided into an arm portion 52 extending generally in front of the vehicle. The shaft portion 50 of each stabilizer bar member 22 is rotatably held by a holder 54 fixedly provided on the vehicle body at a location close to the arm portion 52 and is coaxially arranged. Each shaft portion 50 has an end portion (an end portion opposite to the arm portion 52 side) connected to the actuator 26 as will be described in detail later. On the other hand, the end portion of each arm portion 52 (the end portion opposite to the shaft portion 50 side) is connected to the second lower arm 38 via a link rod 56. The second lower arm 38 is provided with a link rod connecting portion 57. One end of the link rod 56 is connected to the link rod connecting portion 57, and the other end is connected to the end of the arm portion 52 of the stabilizer bar member 22. It is linked so that it can move.

  As shown in FIG. 4, the actuator 26 included in the stabilizer device 14 includes an electromagnetic motor 60 as a drive source, and a speed reducer 62 that reduces and transmits the rotation of the electromagnetic motor 60. The electromagnetic motor 60 and the speed reducer 62 are provided in a housing 64 that is an outer shell member of the actuator 26. One end of the housing 64 is fixedly connected to the end of one shaft portion 50 of the pair of stabilizer bar members 22, while the other of the pair of stabilizer bar members 22 is connected to the housing 64. It is arranged in a state extending from the other end to the inside thereof, and is connected to a speed reducer 62 as will be described in detail later. Further, the other of the pair of stabilizer bar members 22 is rotatably held by the housing 64 via the bush type bearing 70 at the axial intermediate portion thereof.

  The electromagnetic motor 60 includes a plurality of coils 72 fixed on a circumference along the inner surface of the peripheral wall of the housing 64, a hollow motor shaft 74 rotatably held in the housing 64, and the coil 72. And a permanent magnet 76 which is fixedly disposed on the outer periphery of the motor shaft 74. The electromagnetic motor 60 is a motor in which the coil 72 functions as a stator and the permanent magnet 76 functions as a rotor, and is a three-phase DC brushless motor. A motor rotation angle sensor 78 for detecting the rotation angle of the motor shaft 74, that is, the rotation angle of the electromagnetic motor 60 is provided in the housing 64. The motor rotation angle sensor 78 mainly includes an encoder and is used for controlling the actuator 26, that is, controlling the stabilizer device 14.

  The speed reducer 62 includes a wave generator 80, a flexible gear (flex spline) 82, and a ring gear (circular spline) 84. ”And so on). The wave generator 80 is configured to include an elliptical cam and a ball bearing fitted on the outer periphery thereof, and is fixed to one end of the motor shaft 74. The flexible gear 82 has a cup shape in which the peripheral wall portion can be elastically deformed, and a plurality of teeth (400 teeth in the speed reducer 62) are formed on the outer periphery on the opening side of the peripheral wall portion. The flexible gear 82 is connected to and supported by the ends of the other shaft portion 50 of the pair of stabilizer bar members 22 described above. More specifically, the shaft portion 50 of the stabilizer bar member 22 passes through the motor shaft 74, and penetrates the bottom portion of the flexible gear 82 as the output portion of the speed reducer 62 on the outer peripheral surface of the portion extending therefrom. In the state, it is connected to the bottom portion by spline fitting so that relative rotation is impossible. The ring gear 84 is generally ring-shaped and has a plurality of teeth (402 teeth in the present speed reducer 62) formed on the inner periphery, and is fixed to the housing 64. The flexible gear 82 is fitted into the ring gear 84 at two locations located in the major axis direction of the ellipse, and is not meshed at other locations, with its peripheral wall portion being fitted on the wave generator 80 and elastically deformed into an elliptical shape. It is said that. With such a structure, when the wave generator 80 rotates once (360 degrees), that is, when the motor shaft 74 of the electromagnetic motor 60 rotates once, the flexible gear 82 and the ring gear 84 are relatively rotated by two teeth. . That is, the reduction ratio of the reduction gear 62 is 1/200.

  From the above configuration, when the left and right stabilizer bar members 22 are relatively rotated by the operation of the actuator 26, the respective arm portions 52 are relatively rotated while the shaft portions 50 are twisted, and the left and right wheels 16 are rotated. One of the distances between the unsprung and unsprung portions is increased and the other is decreased. In other words, due to the torsional reaction force of each shaft portion 50, one of the upper and lower spring portions of the left and right wheels 16 is separated and the other is moved closer. That is, the stabilizer device 14 generates a stabilizer force as a torsional reaction force, which is a force for relatively approaching and separating the upper and lower spring portions of the left and right wheels 16. In addition, if the relative rotation amount of the left and right stabilizer bar members 22 is changed by operating the actuator 26, the stabilizer force can be changed. That is, the stabilizer device 14 can generate the stabilizer force in a controllable manner.

  The relative rotation amount of the left and right stabilizer bar members 22 here refers to the rotation amount from the reference relative rotation position when the reference relative rotation position of the left and right stabilizer bar members 22 is the reference relative rotation position. This means that the operation of the electromagnetic motor 60 is controlled so that the control relative rotation amount used for controlling the actuator 26 becomes the target relative rotation amount which is the target rotation amount. In addition, since the relative rotation amount of the left and right stabilizer bar members 22 has a corresponding relationship with the operation amount of the actuator 26, that is, the rotation amount of the electromagnetic motor 60, in the control of the stabilizer device 14, Instead of the relative rotation amount, the control for the motor rotation angle acquired by the motor rotation angle sensor 78 is performed. Specifically, when the rotation angle of the electromagnetic motor 60 when the relative rotation position of the left and right stabilizer bar members 22 is the reference relative rotation position is defined as the reference motor rotation angle, from the reference motor rotation angle The operation of the electromagnetic motor 60 is controlled so that the rotation angle of the electromagnetic motor 60 becomes the target motor rotation angle.

iv) Configuration of Control Device In this system 10, as shown in FIG. 1, an electronic control unit (ECU) 90 corresponding to the two stabilizer devices 14 is provided. The ECU 90 is a control device that controls the operation of each stabilizer device 14, specifically, each actuator 26, and includes two inverters 92 as a drive circuit corresponding to the electromagnetic motor 60 included in each actuator 26, CPU, ROM, and RAM Etc., and a controller 96 mainly composed of a computer equipped with the above (see FIG. 12). Each of the inverters 92 is connected to the battery 100 via the converter 98 and is connected to the electromagnetic motor 60 of the corresponding stabilizer device 14. The electromagnetic motor 60 is driven at a constant voltage, and the power supplied to the electromagnetic motor 60 is changed by changing the amount of supplied current. The supply current amount is changed by the inverter 92 changing the ratio (duty ratio) between the pulse on time and the pulse off time by PWM (Pulse Width Modulation).

  In addition to the motor rotation angle sensor 78, the controller 96 includes a steering sensor 102 for detecting an operation angle of the steering wheel, which is an operation amount of the steering operation member as a steering amount, and a lateral acceleration actually generated in the vehicle body. A lateral acceleration sensor 104 that detects a certain actual lateral acceleration and a sprung vertical acceleration sensor 106 that is provided on the mount 48 of the vehicle body and detects a sprung vertical acceleration are connected. The controller 96 is further connected to a brake electronic control unit (hereinafter also referred to as “brake ECU”) 108 which is a control device of the brake system. The brake ECU 108 is connected to a wheel speed sensor 110 that is provided for each of the four wheels and detects the rotational speed of each of the four wheels. Has a function of estimating the traveling speed of the vehicle (hereinafter sometimes referred to as “vehicle speed”). The controller 96 acquires the vehicle speed from the brake ECU 108 as necessary. Further, the controller 96 is also connected to each inverter 92 and controls them to control the electromagnetic motor 60 of each stabilizer device 14. Note that a ROM included in the computer of the controller 96 stores a program related to control of the stabilizer device 14 to be described later, various data, and the like.

<Operation mode of electromagnetic motor>
As shown in FIG. 5, the electromagnetic motor 60 is a Δ-connected three-phase DC brushless motor, and corresponding to each phase (U, V, W), energization terminals 122u, 122v, 122w (hereinafter collectively referred to as “general names”). In some cases, it may be referred to as an “energizing terminal 122”. The inverter 92 includes two switching elements on the high (positive) side and the low (negative) side corresponding to each energization terminal, that is, each phase (U, V, W). That is, three high-potential side switching elements (hereinafter, each of the three switching elements may be referred to as “UHC”, “VHC”, and “WHC”) 124 and three low-potential side switching elements (hereinafter, “3HC”). Each of the two switching elements is provided with 126 (which may be referred to as “ULC”, “VLC”, or “WLC”). Further, the switching element switching circuit, determines the rotation angle (electrical angle) by the detection signals of the three Hall elements H _A provided in the electromagnetic motor 60, H _B, H _C (in the figure, is indicated as H) Then, on / off switching of each of the six switching elements is performed based on the rotation angle. The inverter 92 is connected to a high potential side terminal 130 h and a low potential side terminal 130 l of the battery 100 via a converter 98.

  In the present system 10, the electromagnetic motor 60 is operable in four operation modes, and is operated in one operation mode selected based on conditions set from the four operation modes. The operation mode is determined by the operation state of the inverter 92, in other words, the switching mode of the switching elements 124 and 126. Specifically, the operation mode is switched by changing the ON / OFF switching mode of the switching elements 124 and 126 of the inverter 92.

  The operation mode can be roughly divided into two modes. One of them is a control energization mode, in which ON / OFF control according to the duty ratio, that is, duty control is performed, and an operation mode in which power can be supplied from the battery 100 to the electromagnetic motor 60. is there. The other is an operation mode in which power is not supplied from the battery 100 to the electromagnetic motor 60. In the present system 10, three modes of a brake mode, a free mode, and a standby mode can be adopted. Hereinafter, each operation mode will be described.

i) Control energization mode Referring to FIG. 6, in the control energization mode, each switching element UHC, ULC, VHC, VLC, WHC, WLC is turned on / off by a so-called 120 ° energization rectangular wave drive. OFF is switched according to the rotation angle of the electromagnetic motor 60. Specifically, one switching element among the high potential side switching elements UHC, VHC, WHC and one switching element among the low potential side switching elements ULC, VLC, WLC are turned on (closed state). At the same time, all of the remaining switching elements are turned off (open state), and the two switching elements that are turned on (closed state) correspond to the detection signals of the three hall elements H _A , H _B , and H _C. Be changed. Further, only the low potential side switching elements ULC, VLC, WLC execute the duty control, and the amount of current supplied to the electromagnetic motor 60 is changed by changing the duty ratio. ing. “1 *” in FIG. 6 indicates this. By the way, the switching mode of each switching element differs depending on the direction in which the motor force is generated. For convenience, the directions will be referred to as the right direction (CW direction) and the left direction (CCW direction).

  As described above, the control energization mode is a mode in which the direction in which the electromagnetic motor 60 generates a motor force (hereinafter sometimes referred to as “motor force generation direction”) and the amount of power supplied to the electromagnetic motor 60 can be controlled. In this control energization mode, the electromagnetic motor 60 can generate a motor force having a magnitude corresponding to the amount of supplied current in an arbitrary direction. Therefore, the stabilizer force generated by the stabilizer device 14 can be controlled.

ii) Brake mode In the brake mode, the energization terminals of the electromagnetic motor 60 are electrically connected to each other, and this operation mode is considered as a kind of all-terminal conduction mode. That is, all of the switching elements arranged on one of the high side and the low side are kept in a closed state, and all those arranged on the other of the high side and the low side are kept in an open state. Specifically, in the present system 10, as shown in FIG. 6, all of the high potential side switching elements UHC, VHC, WHC are turned on (closed state), and the low potential side switching elements ULC, VLC are turned on. , WLC are both in the OFF state (open state). The high-potential side switching elements UHC, VHC, and WHC that are turned on are in a state where the phases of the electromagnetic motor 60 are short-circuited with each other. In such a state, a so-called short-circuit braking effect is obtained for the electromagnetic motor 60. Therefore, the actuator 26 exhibits a relatively large resistance even when power is not supplied from the battery 100 to the electromagnetic motor 60 when the actuator 26 is forced to operate at a high speed by an external input such as a roll of the vehicle body.

iii) Free mode In the free mode, energization from the high-potential-side terminal 130h of the battery 100 to the three energization terminals 122 of the electromagnetic motor 60 is prohibited, and the battery 100 is activated from the three energization terminals 122 of the electromagnetic motor 60. Energization of the terminal 130l on the potential side is prohibited. That is, this operation mode can be considered as a kind of all-terminal de-energization mode. Specifically, as shown in FIG. 6, all of the switching elements UHC, ULC, VHC, VLC, WHC, and WLC are turned off (open state). For this reason, in this operation mode, the braking effect by the electromagnetic motor 60 is hardly obtained, or even if obtained, only a relatively small effect is obtained. Therefore, when this operation mode is adopted, when an external input acts on the actuator 26, the actuator 26 operates without receiving much resistance.

iv) Standby mode In the standby mode, switching of each switching element is executed in accordance with the command of the motor force generation direction, but no power is actually supplied from the power source to the electromagnetic motor 60. As shown in FIG. 6, the switching elements UHC, ULC, VHC, VLC, WHC, and WLC are turned on / off according to the rotational phase of the electromagnetic motor 60 as in the control energization mode. However, unlike the control energization mode, duty control is not performed in any of the low potential side switching elements ULC, VLC, and WLC (it can also be said that duty control is performed so that the duty ratio becomes 0). That is, since the pulse-on time does not exist and the low potential side switching elements ULC, VLC, WLC are actually in the OFF state (open state), the electromagnetic motor 60 is actually connected to the battery 100 from the battery 100. The power is not supplied. “0 *” in FIG. 6 indicates this.

  In the standby mode, since electric power is not supplied to the electromagnetic motor 60, the operation of the electromagnetic motor 60 cannot be controlled. However, since the switching elements are switched as described above, it is possible to respond quickly to the transition from this mode to the control energization mode, so that control delay is small, quick response, response, etc. There is an advantage of superiority. In addition, since switching of the switching element is performed, a certain amount of electromotive force is generated when the electromagnetic motor 60 is rotated by an external input by adjusting the rotation direction of the electromagnetic motor 60 and the motor force generation direction. It is possible. In this case, a certain degree of braking effect is obtained with respect to the rotation of the electromagnetic motor 60, and resistance to the operation of the actuator 26 is generated. In addition, the braking effect by this operation mode is an intermediate braking effect between the above-described brake mode and free mode.

<Control of vehicle stabilizer system>
In the present system 10, as described above, the stabilizer device 14 controllably generates a stabilizer force that is a force for relatively approaching and separating the spring top and the spring bottom of the left and right wheels 16 in the control energization mode. It is possible. Therefore, by controlling the stabilizer force generated by the stabilizer device 14, it is possible to execute control for suppressing the roll of the vehicle body caused by turning of the vehicle, undulation of the traveling road surface of the vehicle, and the like. There are two types of restraint control of the roll of the vehicle body in this system 10, that is, a roll amount reduction control for reducing the roll amount of the vehicle body and a roll vibration damping control for attenuating vibration in the roll direction of the vehicle body. A control in which these two controls are integrated is executed. In this integrated control, the relative rotation amount of the pair of stabilizer bar members 22 in order to generate an appropriate stabilizer force based on the roll moment received by the vehicle body, the roll speed of the vehicle body, etc. in the stabilizer device 14, that is, The motor rotation angle of the electromagnetic motor 130 is controlled. Specifically, the rotation amount from the reference motor rotation angle is defined as a motor rotation angle (hereinafter sometimes referred to as “control motor rotation angle”) θ _S used for the control, and the control motor rotation angle θ _S is The electromagnetic motor 60 is controlled so that the target motor rotation angle θ ^* is determined based on the roll moment received by the vehicle body, the roll speed of the vehicle body, and the like.

In the present system 10, the above-described target motor rotation angle θ ^* is determined by summing the target motor rotation angle components, which are target value components for each control of roll amount reduction control and roll vibration damping control. The components for each control are
Roll amount reduction target motor rotation angle component (roll amount reduction component) θ ^* _T
Roll vibration attenuation target motor rotation angle component (roll vibration attenuation component) θ ^* _G
It is. In the following, each of the roll amount reduction control and roll vibration damping control will be described in detail with a focus on the determination method of each target motor rotation angle component, and the power supplied to the electromagnetic motor 60 based on the target motor rotation angle will be described. The determination and calculation of the control motor rotation angle will be described in detail.

i) Roll amount reduction control In roll amount reduction control, the roll amount corresponding to the roll moment received by the vehicle body due to the turn to reduce the roll amount of the vehicle body caused by the turn when the vehicle turns. Generate a reduction force. Specifically, first, as the lateral acceleration that indicates the roll moment received by the vehicle body, the estimated lateral acceleration Gyc estimated based on the steering angle δ of the steering wheel and the vehicle traveling speed v, and the actually measured actual lateral acceleration Gyr. Based on the above, the control lateral acceleration Gy ^* , which is the lateral acceleration used for the control, is determined according to the following equation.
Gy ^* = K ₁ · Gyc + K ₂ · Gyr
Here, K ₁ and K ₂ are gains, and the roll amount reduction component θ ^* _T is determined based on the control lateral acceleration Gy ^* determined as described above. The controller 96 stores map data of the roll amount reduction component θ ^* _T having the control lateral acceleration Gy ^* as a parameter, and the roll amount reduction component θ ^* _T is determined with reference to the map data. In the present system 10, execution of the roll amount reduction control is started when the actual lateral acceleration Gyr for the roll-moment index exceeds the set閾加speed Gy _1, the actual lateral acceleration Gyr is set閾加speed Gy ₁ below When it becomes, it is stopped. That is, the set threshold acceleration Gy ₁ functions as a roll amount reduction control start threshold value for starting execution of the roll amount reduction control and also functions as a roll amount reduction control end threshold value for ending the control.

ii) Roll vibration damping control In roll vibration damping control, in order to attenuate the vibration in the roll direction of the vehicle body, the stabilizer force is set to a roll vibration damping force having a magnitude corresponding to the roll speed of the vehicle body with respect to the horizontal plane. I have control. Specifically, first, the sprung absolute velocity Vu is calculated based on the sprung vertical acceleration Gu of each sprung portion detected by a sprung vertical acceleration sensor 106 provided corresponding to each wheel 16. An average sprung absolute speed Vu _AVR corresponding to the right front wheel, which is an average value of the absolute sprung speed corresponding to the right front wheel and the absolute sprung speed corresponding to the right rear wheel, and the absolute sprung speed corresponding to the left front wheel The difference between the average value on the left wheel corresponding to the average sprung speed corresponding to the wheel and the average absolute speed on the left wheel Vu _AVL is calculated, and the difference between the speed and the average value between the tread width on the front wheel side and the tread width on the rear wheel side Based on the average tread width L, the roll speed ω of the vehicle body is determined according to the following equation.
ω = (Vu _AVR −Vu _AVL ) / L
Based on the determined roll speed ω of the vehicle body, the damping moment M is calculated according to the following equation.
M = Cr · ω
Here, Cr is a gain for generating a damping force corresponding to the operation speed in the roll direction of the vehicle body, and can be considered as a damping coefficient for the roll operation of the vehicle body. Based on the damping moment M thus determined, the roll vibration damping component θ ^* _G is determined. The controller 96 stores map data of the roll vibration damping component θ ^* _{G using} the damping moment M as a parameter, and the roll vibration damping component θ ^* _G is determined with reference to the map data. In the present system 10, execution of the roll-vibration damping control is started when the vehicle body roll speed as roll speed indicator which indicates the roll of the vehicle body speed omega exceeds the set threshold velocity omega _1, the roll speed omega is When the set threshold speed ω ₁ does not exceed the set time t ₀ , it is stopped. That is, the set threshold speed ω ₁ functions as a roll vibration attenuation control start threshold value for starting execution of roll vibration attenuation control and also functions as a roll vibration attenuation control end threshold value for ending the control.

iii) Determination of power supplied to electromagnetic motor As described above, when the roll amount reduction component θ ^* _T and the roll vibration damping component θ ^* _G are determined, the target motor rotation angle θ ^* is determined according to the following equation. The
θ ^* = θ ^* _T + θ ^* _G
Then, the electromagnetic motor 130 is controlled so that the control motor rotation angle θ _S becomes the determined target motor rotation angle θ ^* . In the control of the electromagnetic motor 60, the electric power supplied to the electromagnetic motor 60 has a motor rotation angle deviation Δθ (= θ ^* −θ _S ) that is a deviation of the control motor rotation angle θ _{S from} the target motor rotation angle θ ^* . To be determined. Specifically, it is determined according to a feedback control method based on the motor rotation angle deviation Δθ. Specifically, first, as will be described in detail later, the control motor rotation angle θ _S is calculated based on the detection value of the motor rotation angle sensor 78 included in the electromagnetic motor 60. Then, the motor rotation angle deviation Δθ is recognized based on the control motor rotation angle θ _S , and then the target supply current i ^* is determined according to the following equation using it as a parameter.
i ^* = K _P · Δθ + K _I · Int (Δθ)
This equation follows the PI control law. The first term and the second term mean the proportional term and the integral term, respectively, and K _P and K _I mean the proportional gain and the integral gain, respectively. Int (Δθ) corresponds to an integral value of the motor rotation angle deviation Δθ. The target supply current i ^* determined in this way represents the direction of generation of the motor force of the electromagnetic motor 60 by its sign, and the drive control of the electromagnetic motor 60 is based on the target supply current i ^* . Thus, the duty ratio and motor force generation direction for driving the electromagnetic motor 60 are determined. Then, a command regarding the duty ratio and the direction of motor force generation is issued to the inverter 92, and the drive control of the electromagnetic motor 60 based on the command is performed by the inverter 92.

iv) Calculation of control motor rotation angle As the control motor rotation angle used for control, it is conceivable to employ the actual motor rotation angle detected by the motor rotation angle sensor 78. In this case, the reference motor rotation angle serving as a reference for control is the actual motor rotation angle at the start of control, and the electromagnetic motor 60 is set such that the angle rotated from the actual motor rotation angle at the start of control becomes the target motor rotation angle. Is controlled. As described above, when the roll amount reduction control is executed using the actual motor rotation angle at the start of control as the reference motor rotation angle, the roll amount reduction control in the present system 10 is performed as follows. Since it is started when the acceleration Gy ₁ is exceeded, the target motor rotation angle at the time when the roll amount reduction control is started increases to some extent, and the actuator 26 is suddenly and greatly operated at the start of the roll amount reduction control. It will be. This will be specifically described below with reference to the drawings.

As shown in FIG. 7A, the actual lateral acceleration Gyr as a roll moment index for indexing the roll moment received by the vehicle body increases as shown in FIG. 7A, and the roll amount decreases as the actual lateral acceleration Gyr increases. The component θ ^* _T increases as shown in FIG. Roll amount reduction control is not executed when the actual lateral acceleration Gyr is set閾加speed Gy ₁ below, is executed from the time t ₁ when the actual lateral acceleration Gyr exceeds the set閾加speed Gy _1. In the system 10, if the actual lateral acceleration Gyr is set閾加speed Gy ₁ below, operation mode of the electromagnetic motor 60 is a mode of operation the power supply from the battery 100 to the electromagnetic motor 60 is not performed, the actual lateral When the acceleration Gyr exceeds the set threshold acceleration Gy ₁ , the control energization mode is an operation mode in which power can be supplied from the battery 100 to the electromagnetic motor 60. Incidentally, in the present system 10, the standby mode is adopted as an operation mode in which power supply from the battery 100 to the electromagnetic motor 60 is not performed.

In the standby mode, as described above, a certain degree of braking effect is obtained with respect to the rotation of the electromagnetic motor 60. Therefore, the actual motor rotation angle θ _R detected by the motor rotation angle sensor 78 is shown in FIG. As shown by the solid line, the value is maintained at approximately 0 until the control start time t ₁ . Incidentally, in this system 10, the motor rotation angle of the electromagnetic motor 60 corresponding to the neutral relative rotation position, which is a relative rotation position in a state where the pair of stabilizer bar members 22 are assumed not to rotate relative to each other, is set to the neutral motor rotation. The neutral motor rotation angle is 0 °. When the actual lateral acceleration Gyr exceeds the set threshold acceleration Gy ₁ , the electromagnetic motor 60 is suddenly operated so that the actual motor rotation angle becomes the roll amount reduction component α at that time, and the actual motor rotation angle. Increase rapidly (solid line in FIG. 7C). As described above, in the roll amount reduction control based on the actual motor rotation angle, the actuator 26 is suddenly actuated at the start of the control, and there is a possibility that an impact may be caused by the rapid actuation.

In view of the above, in the present system 10, when the roll amount reduction control is executed, it is detected by the motor rotation angle sensor 78 in order to suppress the rapid operation of the actuator 26 at the start of the roll amount reduction control. The control motor rotation angle θ _S is calculated on the assumption that the actual motor rotation angle θ _R is rotating the roll amount reduction component α. Specifically, based on the actual motor rotation angle θ _R , the control motor rotation angle θ _S is calculated according to the following equation.
θ _S = θ _R + α
If the control motor rotation angle θ _S is calculated in this way, the actual motor rotation angle θ _R at the start of control is 0, so the control motor rotation angle θ _S at the start of control is reduced by the roll amount. It becomes equal to the component α, and the operation amount of the actuator 26 becomes zero at the start of the roll amount reduction control. That is, the reference motor rotation angle is set so that the control motor rotation angle θ _S at the start of control becomes equal to the roll amount reduction component α at the start time, so that at the start of the roll amount reduction control, The motor rotation angle deviation Δθ becomes 0, and the rapid operation of the actuator 26 at the start of control can be suppressed.

  Specifically, referring to FIG. 7, as shown in FIG. 7D, the control motor rotation angle (solid line) at the start of control is an angle that has already been α-rotated from the neutral motor rotation angle. It is already equal to the target motor rotation angle (dotted line). For this reason, the motor rotation angle deviation Δθ at the start of control becomes 0, and the operation amount of the actuator becomes 0. Thereafter, as the target motor rotation angle (dotted line) increases, the motor rotation angle deviation Δθ increases, and the actual motor rotation angle also gradually increases as shown by the dotted line in FIG. As can be seen from FIG. 7C, when the roll amount reduction control is executed with the actual motor rotation angle at the start of the control as the reference motor rotation angle, the operation of the actuator 26 at the start of the control becomes abrupt ( (Solid line), when the roll amount reduction control is executed with the motor rotation angle at which the control motor rotation angle at the control start time becomes equal to the roll amount reduction component α at the control start time as the reference motor rotation angle, The operation of the actuator 26 is gentle (dotted line). Therefore, in the roll amount reduction control in the present system 10, the occurrence of an impact accompanying the rapid operation of the actuator 26 at the start of the control is suppressed.

On the other hand, consider the case where the reference motor rotation angle in the roll vibration damping control is set according to the same rule as in the roll amount reduction control as described above. That is, consider a case where the reference motor rotation angle is set so that the control motor rotation angle at the start of roll vibration attenuation control is equal to the roll vibration attenuation component at the start of control. When the roll speed ω of the vehicle body indexing roll vibration changes as shown in FIG. 8A, the roll vibration attenuation component θ ^* _G is changed as shown in FIG. ). Roll-vibration damping control is executed from the time t ₂ that roll speed omega exceeds the set threshold speed omega ₁ is started, is continued until a state where the roll velocity omega does not exceed a set threshold speed omega ₁ continues set time. Even in the roll vibration damping control, when the control is not executed, the operation mode of the electromagnetic motor 60 is set to the standby mode, and the actual motor rotation angle θ _R at the start time t ₂ of the roll vibration damping control. Is substantially maintained at 0 as shown by the solid line in FIG.

When the reference motor rotation angle in the roll vibration damping control is set in the same manner as the roll amount reduction control, the control motor rotation angle θ _S is calculated as shown in the following equation.
θ _S = θ _R + β
Here, β is a roll vibration attenuation component at time t ₂ when the roll speed ω exceeds the set threshold speed ω ₁ , and is larger than the roll amount reduction component α. This is because the frequency of occurrence of roll vibration is relatively high compared to the frequency of turning of the vehicle, and therefore, when the roll vibration damping component β is set low, the frequency of executing roll vibration damping control becomes considerably high.

When the control motor rotation angle θ _S is calculated according to the above equation, as shown in FIG. 8D, the control motor rotation angle at the control start time t ₂ (solid line) is already β from the neutral motor rotation angle. It becomes a rotating angle and is equal to the target motor rotation angle (dotted line). As the target motor rotation angle (dotted line) changes, the control motor rotation angle changes so as to follow the target motor rotation angle. At that time, as shown by the solid line in FIG. 8C, the actual motor rotation angle θ _R starts to be controlled from the neutral motor rotation angle and changes greatly deviating from the neutral motor rotation angle. As described above, the neutral motor rotation angle is a motor rotation angle in a state in which the pair of stabilizer bar members 22 are not relatively rotated. Therefore, the actual motor rotation angle θ _R is greatly deviated from the neutral motor rotation angle. In the case of a change, it is considered that the actuator 26 is controlled with the stabilizer bar 20 being largely twisted. That is, the actuator 26 is controlled on the basis of the state in which the stabilizer bar 20 is largely twisted. This is due to the fact that the reference motor rotation angle is set so that the control motor rotation angle at the start of the roll vibration attenuation control becomes the roll vibration attenuation component β having a relatively large value. In order to control the actuator 26 with reference to a state where the rotation is not greatly twisted, the reference motor rotation angle is set so that the control motor rotation angle at the start of the roll vibration attenuation control is smaller than the roll vibration attenuation component β. There is a need.

In view of the above, in the present system 10, when roll vibration damping control is executed, the start point of roll vibration damping control is to control the actuator 26 based on the state in which the stabilizer bar 20 is hardly twisted. The reference motor rotation angle is set so that the control motor rotation angle is zero. That is, the control motor rotation angle θ _S is calculated using the reference motor rotation angle as the actual motor rotation angle at the start of control. Specifically, the actual motor rotation angle θ _R detected by the motor rotation angle sensor 78 is directly adopted as the control motor rotation angle θ _S. As described above, when the actual motor rotation angle θ _R is adopted as the control motor rotation angle θ _S , the actual motor rotation angle θ _R is obtained as shown in FIG. 8C by the target motor rotation angle (dotted line). ), And generally changes around the neutral motor rotation angle. Thus, in the present system 10, the reference motor rotation angle in the control of the electromagnetic motor 60 is set based on different rules at the start time of the roll amount reduction control and the start time of the roll vibration damping control.

<Control program>
In the present system 10, the stabilizer force generated by the stabilizer device 14 is controlled by the controller 96 executing a stabilizer device control program whose flowchart is shown in FIG. 9. This program is repeatedly executed at a set time interval Δt while the ignition switch is in the ON state. The control flow will be briefly described below with reference to the flowchart shown in the figure. This control program is executed for each actuator 26 of the pair of stabilizer devices 14 provided for the front and rear wheels. In the following description, one control program is taken into consideration for simplification of description. Processing for the actuator 26 will be described.

In the processing according to this program, first, in step 1 (hereinafter simply referred to as “S1”, the same applies to other steps), processing for executing the roll amount reduction component determination subroutine shown in the flowchart of FIG. 10 is performed. Executed. In this subroutine, first, in S21, the vehicle speed v is acquired based on the calculated value of the brake ECU 108, and in S2, the steering wheel operating angle δ is acquired based on the detected value of the steering sensor 102. Subsequently, in S23, the estimated lateral acceleration Gyc is estimated based on the acquired vehicle speed v and the operation angle δ. In S24, the actual lateral acceleration Gyr, which is the lateral acceleration actually generated in the vehicle body, is detected by the lateral acceleration sensor 104. Obtained based on the detected value. In S25, the control lateral acceleration Gy ^* is determined from the estimated lateral acceleration Gyc and the actual lateral acceleration Gyr as described above. Based on the determined control lateral acceleration Gy ^* , in S26, the roll amount reduction component θ. ^* _T is determined.

In S27, the absolute value of the actual lateral acceleration Gyr for the roll-moment index is, whether exceeds the set閾加speed Gy ₁ is determined. If it is determined that the absolute value of the actual lateral acceleration Gyr exceeds the set threshold acceleration Gy ₁ , a roll amount reduction control start flag F indicating whether or not the execution of the roll amount reduction control is started in S28. The flag value of _T is set to 1. When the flag value of the flag F _T is a 1 indicates that the execution of the roll amount reduction control is started, if there is a 0, the execution of the roll amount reduction control is ended It shows that. Next, in S29, it is determined whether the flag value of the roll amount reduction control start flag F _TP in the last execution of this program is zero, if it is determined to be 0, in S30, the control The correction value α for calculating the motor rotation angle θ _S is the roll amount reduction component θ ^* _T determined in S26. Further, when the absolute value of the actual lateral acceleration Gyr is determined not to exceed the set閾加speed Gy ₁ in S27, in S31, to indicate that execution of the roll amount reduction control is ended, the roll amount the flag value of the reduction control start flag F _T is zero, in S32, the roll amount reducing component theta ^* _T is changed to 0.

After execution of the roll amount reduction component determination subroutine, processing for executing the roll vibration damping component determination subroutine shown in the flowchart of FIG. 11 is executed in S2. In this subroutine, in S41, each sprung vertical acceleration Gu is detected by each sprung vertical acceleration sensor 106 provided in each wheel 16, and in S42, each sprung absolute speed based on each sprung vertical acceleration Gu. Vu is calculated. Next, in S43, based on each sprung absolute speed Vu calculated corresponding to each wheel 16, a right wheel corresponding average sprung absolute speed Vu _AVR and a left wheel corresponding average sprung absolute speed Vu _AVL are calculated, In S44, the roll speed ω is calculated based on the speed difference between the right wheel-corresponding average sprung absolute speed Vu _AVR and the left wheel-corresponding average sprung absolute speed Vu _AVL as described above. In S45, the damping moment M is calculated based on the calculated roll speed ω, and in S46, the roll vibration damping component θ ^* _G is determined based on the damping moment M.

Subsequently, in S47, it is determined whether or not the absolute value of the roll speed ω as the roll speed index exceeds the set threshold speed ω ₁ . If it is determined that the absolute value of the roll speed ω does not exceed the set threshold speed ω ₁ , a roll vibration damping control start flag F _G indicating whether or not the execution of the roll vibration damping control is started in S48. It is determined whether or not the flag value is set to 1. When the flag value of the flag F _G is the 1 indicates that the execution of the roll-vibration damping control is started, if there is a 0, the execution of the roll-vibration damping control is finished It shows that. When the flag value of the roll-vibration damping control start flag F _G is determined to be a 1, at S49, to measure the duration of the state where the absolute value of the roll speed omega does not exceed the set threshold speed omega ₁ It is subject to certain time Δt to measurement time t for, in S50, whether the measured time t the set time t ₀ or more is determined. Change the measured time t is determined that the setting is the time t ₀ or more, in S51, the flag value of the roll-vibration damping control start flag F _G is set to 0, in S52, the roll-vibration damping component theta ^* _G 0 Is done. Further, when the absolute value of the roll speed omega is determined to exceed the set threshold speed omega ₁ in S47, in S53, the measured time t is reset to 0, in S54, the roll-vibration damping control start flag F The flag value of _G is set to 1.

After execution of the roll vibration damping component determination subroutine, in S3, the roll amount reduction component θ ^* _T and the roll damping component θ ^* _G are summed to determine the target motor rotation angle θ ^* , and in S4, the motor Based on the rotation angle sensor 78, the actual motor rotation angle θ _R is acquired. Next, in S5, it is determined whether or not any of the roll amount reduction control and roll vibration damping control is executed. Specifically, whether or not each of the flag values of the roll amount reduction control start flag F _T and the roll-vibration damping control start flag F _G is set to 0 is determined. If it is determined that each flag value is 0, the flag value of the reference motor rotation angle setting flag F _K is set to 0 in S6. The flag F _K indicates whether or not the reference motor rotation angle is set, and if it is set, which control is set corresponding to the flag F _K. When it is 0, it indicates that the reference motor rotation angle is not set. When it is 1, it indicates that the reference motor rotation angle is set corresponding to the roll vibration damping control. 2 indicates that the reference motor rotation angle is set corresponding to the roll amount reduction control. Next, in S <b> 7, a control signal for setting the operation mode of the electromagnetic motor 60 to the standby mode is transmitted to the inverter 92.

Further, when it is determined that each of the flag values of the roll amount reduction control start flag F _T and the roll-vibration damping control start flag F _G is not zero in S5, in S8, the reference motor rotation angle setting flag It is determined whether or not the flag value of F _K is 0. If the flag value is determined to be zero, in S9, whether or not the flag value of the roll-vibration damping control start flag F _G is the 1 is determined, the flag value is 1 and when it is determined, in order to set the reference motor rotation angle corresponding to the roll-vibration damping control, in S10, the flag value of the reference motor rotation angle setting flag F _K is set to 1. Further, when the flag value of the roll-vibration damping control start flag F _G is determined to be zero, in order to set the reference motor rotation angle corresponding to the roll amount reduction control, in S11, the reference angular position The flag value of the setting flag F _K is set to 2.

Subsequently, in S12, the flag value of the reference motor rotation angle setting flag F _K whether there is a 1 is determined. If it is determined that the flag value is 1, in S13, the actual motor rotation angle θ _R detected by the motor rotation angle sensor 78 is determined as the control motor rotation angle θ _S , and the flag value is determined. Is determined to be 2, in S14, the sum of the actual motor rotation angle θ _R and the correction value α is determined as the control motor rotation angle θ _S. Next, in S15, a motor rotation angle deviation Δθ, which is a deviation of the control motor rotation angle θ _{S from} the target motor rotation angle θ ^* , is determined, and in S16, the target supply current i ^* is obtained according to the equation according to the aforementioned PI control law ^. Is determined. Then, in S17, after a control signal based on the determined target supply current i ^* is transmitted to the inverter 92, one execution of this program ends.

<Functional configuration of controller>
The controller 96 that executes the stabilizer device control program can be considered to have a functional configuration as shown in FIG. 12 in view of its execution processing. As can be seen from the figure, the controller 96 uses the target relative rotation amount determination unit 140 as a function unit that executes the processes of S1 to S3, that is, a function unit that determines the target motor rotation angle θ ^* as the target relative rotation amount. The control relative rotation amount determination unit 142 is a function unit that executes the processes of S8 to S14, that is, a function unit that determines the control motor rotation angle θ _S indicating the rotation amount from the reference motor rotation angle. As a functional unit that executes the processes of S17, S27 to S32, that is, as a functional unit that executes the roll amount reduction control, the roll amount reduction control execution unit 144 is replaced with a functional unit that executes the processes of S15 to S17, S47 to S52, That is, the roll vibration attenuation control execution unit 146 is provided as a functional unit that executes roll vibration attenuation control. The target relative rotation amount determination unit 140 functions as a functional unit that executes the processes of S21 to S26, that is, as a functional unit that determines the roll amount reduction component, and performs the processing of S41 to S46. A roll vibration damping component determination unit 150 is provided as a function unit to be executed, that is, a function unit that determines a roll vibration damping component. Incidentally, since the control motor rotation angle θ _S cannot be calculated without setting the reference motor rotation angle as the reference relative rotation position, the control relative rotation amount determination unit 142 serves as the reference relative rotation position setting unit. It is considered to have a function.

<Modification>
In the system 10, when the roll vibration damping control is executed, the actual motor rotation angle θ detected by the motor rotation angle sensor 78 so as to control the actuator 26 with reference to a state in which the stabilizer bar 20 is hardly twisted. _R is adopted as the control motor rotation angle θ _S as it is, but in order to suppress the rapid operation of the actuator 26 at the start of the roll vibration attenuation control to some extent, the reference motor rotation angle corresponding to the roll vibration attenuation control is set to the roll A reference motor rotation angle set corresponding to the amount reduction control may be used. That is, the reference motor rotation angle may be set so that the control motor rotation angle at the start of the roll vibration attenuation control becomes a roll amount reduction component α smaller than the roll vibration attenuation component β. Specifically, the control motor rotation angle θ _S in the roll vibration damping control may also be calculated according to the following equation, similarly to the roll amount reduction control.
θ _S = θ _R + α

When the control motor rotation angle θ _S in the roll vibration attenuation control is calculated as described above, the control motor rotation angle θ _S is converted into a roll vibration attenuation component θ ^* _G (dotted line) as shown in FIG. It changes following (solid line). Then, as shown in FIG. 13C, the actual motor rotation angle θ _R changes substantially around the neutral motor rotation angle, and the change of the actual motor rotation angle θ _R at the control start time t ₃ is moderate to some extent. It will be something. That is, if the reference motor rotation angle in the roll vibration damping control is the reference motor rotation angle set corresponding to the roll vibration damping control, the actuator 26 is controlled based on a state in which the twist of the stabilizer bar 20 is suppressed to some extent. It becomes possible to make the operation of the actuator 26 at the start of the control a slow movement to some extent.

  Further, in the present system 10, when neither roll vibration damping control nor roll amount reduction control is executed, the standby mode is adopted as the operation mode of the electromagnetic motor 60, but the brake mode or the free mode is adopted. May be. If the brake mode is employed as the operation mode of the electromagnetic motor, the actual motor rotation angle is difficult to deviate from the neutral motor rotation angle, and the actuator 26 can be controlled based on a state in which the stabilizer bar is less twisted. Further, if the free mode is adopted as the operation mode of the electromagnetic motor, it is possible to ensure the riding comfort of the vehicle when any control is not executed. Note that the actuator 26 in the present system 10 employs the reduction gear 62 having a relatively high reduction ratio as described above. Therefore, even if the free mode is adopted as the operation mode of the electromagnetic motor 60, the actual motor The rotation angle is not so far from the neutral motor rotation angle.

  10: Vehicle stabilizer system 16: Wheel 22: One pair of stabilizer bar members (one pair of torsion bars) 26: Actuator 38: Second lower arm (wheel holding member) 50: Shaft portion 52: Arm portion 60: Electromagnetic motor 62 : Reduction gear 64: Housing 90: Electronic control unit (control device) 140: Target relative rotation amount determination unit 142: Control relative rotation amount determination unit (reference relative rotation position setting unit) 144: Roll amount reduction control execution unit 146: Roll vibration damping control execution unit

Claims (5)

A pair of torsion bars provided corresponding to the left and right wheels, each extending in the vehicle width direction, each tip being connected to a wheel holding portion for holding a corresponding one of the left and right wheels; ,
An actuator capable of changing the torsional reaction force generated by the pair of torsion bars by holding the pair of torsion bars so as to be rotatable relative to each other and rotating the pair of torsion bars relative to each other. When,
As an indicator of the actual relative rotation amount of the pair of torsion bars, a control relative rotation amount that is a relative rotation amount from a set reference relative rotation position is used, and the control relative rotation amount is a target relative rotation amount. A vehicle stabilizer system comprising: a control device that controls a torsional reaction force generated by the pair of torsion bars by controlling the actuator to have a rotation amount;
The control device is
A roll vibration damping control execution unit for performing roll vibration damping control for controlling the torsional reaction force so that at least a part thereof is a roll vibration damping force for damping the roll vibration of the vehicle body;
A roll amount reduction control execution unit that executes roll amount reduction control for controlling the torsional reaction force so that at least a part thereof becomes a roll amount reduction force for reducing the roll amount generated due to turning of the vehicle. When,
The reference relative -rotation position, at the beginning of the roll-vibration damping control of the start time and the rolling amount reduction control, possess a reference relative rotational position setting unit that sets, based on different rules,
The relative rotation position of the pair of torsion bars in a state where the pair of torsion bars are assumed not to rotate relative to each other is a neutral relative rotation position and a component constituting the target relative rotation amount, When the component for the roll amount reduction control is defined as the roll amount reduction component and the component for constituting the target relative rotation amount and the component for the roll vibration damping control is defined as the roll vibration damping component,
The controller further includes
A relative rotation amount from the neutral relative rotation position corresponding to the torsional reaction force to be generated is determined as the target relative rotation amount, and the roll amount is determined according to a roll moment index value indicating a roll moment received by the vehicle body A reduction component is determined, and a target relative rotation amount determination unit that determines the roll vibration attenuation component according to a value of a roll speed index that indicates a roll vibration speed of the vehicle body,
The reference relative rotation position setting unit is
The reference relative rotation position is: (i) the roll amount reduction component at which the control relative rotation amount at that time is determined by the target relative rotation amount determination unit at the start time of the roll amount reduction control. And (ii) at the start of the roll vibration attenuation control, the control relative rotation amount at that time is determined by the target relative rotation amount determination unit at that time. A vehicle stabilizer system configured to be set to be less than components . When the component that constitutes the target relative rotation amount and the component for the roll amount reduction control is defined as a roll amount reduction component,
The target relative rotation amount determination unit is configured to determine the roll amount reduction component according to a value of a roll moment index that indicates a roll moment received by the vehicle body,
The roll amount reduction control execution unit is configured to start execution of the roll amount reduction control when a value of the roll moment index exceeds a roll amount reduction control start threshold,
The roll vibration damping control execution unit is configured to start execution of the roll vibration damping control when a value of the roll speed index exceeds a roll vibration damping control start threshold,
The roll vibration damping control start threshold is
The roll vibration damping component determined when the roll speed index value exceeds the roll vibration damping control start threshold is determined when the roll moment index value exceeds the roll amount reduction control start threshold. Is set to be more than the roll amount reducing component.
The reference relative rotation position setting unit is
When the roll amount reduction control is started at the reference relative rotation position, the control relative rotation amount at that time becomes equal to the roll amount reduction component determined by the target relative rotation amount determination unit at that time. And set
2. The vehicle according to claim 1 , wherein at the start of the roll vibration damping control, the reference relative rotation position is set to the reference relative rotation position set in the previous roll amount reduction control. Stabilizer system. The reference relative rotation position setting unit is
2. The vehicle stabilizer system according to claim 1, wherein the reference relative rotation position is set so that the relative rotation amount for control at that time becomes zero at the start time of the roll vibration damping control. 3. . The roll vibration attenuation control execution unit is configured to be able to execute the roll vibration attenuation control in parallel with the roll amount reduction control,
When the execution of the roll amount reduction control is already started, the reference relative rotation position setting unit sets the reference relative rotation position to the roll amount reduction control even if execution of the roll vibration damping control is started. The vehicle stabilizer system according to any one of claims 1 to 3 , wherein the vehicle stabilizer system is configured to be maintained at the reference relative rotational position set at a start time of the vehicle. The roll amount reduction control execution unit is configured to be able to execute the roll amount reduction control in parallel with the roll vibration damping control,
When the execution of the roll vibration damping control has already started, the reference relative rotational position setting unit sets the reference relative rotational position to the roll vibration damping control even when the roll amount reduction control is started. The vehicle stabilizer system according to any one of claims 1 to 4 , wherein the vehicle stabilizer system is configured to be maintained at the reference relative rotational position set at a start time of the vehicle.

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