JP4962272B2 - Vehicle vibration suppression control device - Google Patents

Description

  The present invention relates to a vibration damping control device for a vehicle such as an automobile, and more specifically, controls a torque (hereinafter referred to as “wheel torque”) that acts between a vehicle wheel and a grounding road surface. The present invention relates to a vibration suppression control device that suppresses vibration of a vehicle body.

Vehicle vibrations such as pitch and bounce vibrations while the vehicle is running are generated by braking / driving force (or inertial force) acting on the vehicle body during acceleration / deceleration of the vehicle or other external force acting on the vehicle body. It is reflected in the wheel torque. Therefore, in the field of vehicle vibration suppression control, it has been proposed to adjust the wheel torque through vehicle braking / driving force control to suppress vibration of the vehicle body while the vehicle is running (for example, Patent Documents). 1 and 2). In the vibration suppression control of vehicle body vibration by such wheel torque or braking / driving force control, when fluctuations in wheel torque due to vehicle acceleration / deceleration requests or turning requests are expected, or when external force (disturbance) acts on the vehicle body, Pitch / bounce vibration generated in the vehicle body using a motion model of vehicle body vibration that is constructed assuming a so-called sprung vibration of the vehicle body or a mechanical model of sprung / unsprung vibration when there is a variation in torque. The wheel torque or braking / driving force is adjusted so that the predicted vibration is suppressed. In the case of this type of vibration suppression control, the generation of vibration energy is suppressed by adjusting the source of the force that generates vibration, rather than by absorbing vibration energy generated as in the case of vibration suppression control by the suspension. Therefore, the vibration damping action is relatively quick and the energy efficiency is good. Further, in the vibration damping control as described above, since the object to be controlled is concentrated on the wheel torque or the braking / driving force of the wheel, the control adjustment is relatively easy.
JP 2004-168148 A JP 2006-69472 A JP 09-51309 A JP-A-2005-178531 JP2005-182405

  As described above, the vibration suppression control by the wheel torque control as described above is performed when the fluctuation of the wheel torque due to the acceleration / deceleration request or the turning request of the vehicle is expected, or an external force (disturbance) acts on the vehicle body. When the wheel torque varies, the vibration of the vehicle body caused by the wheel torque variation is to be suppressed by adjusting the braking / driving force of the wheel or the wheel torque.

  Among the above vibration suppression controls, the former control for suppressing the vibration caused by the fluctuation of the wheel torque due to the acceleration / deceleration request or the turning request for the vehicle is, in short, the driver or the automatic travel control (including the motion control). ) Required acceleration / deceleration (typically demanded braking / driving torque) given to the vehicle driving device or braking device from the vehicle and / or turning demand given to the vehicle steering device (typically target steering angle) ), The acceleration / deceleration request amount is compensated in order to remove or reduce the vibration component that causes the vibration of the vehicle body in the acceleration / deceleration request amount and / or the turn request amount, and the compensated acceleration / deceleration request amount thereafter. The operation of the driving device or the braking device is controlled based on the above. Therefore, in this control, in principle, when the acceleration / deceleration request for the vehicle is realized, the component that causes the vibration of the vehicle body has already been removed or reduced, and the turning request is realized. In this case, since the component that causes the vibration of the vehicle body is canceled or reduced, the generation of the force (vibration force or vibration forcing force) that causes the vibration in the vehicle body is suppressed. Expected (and are therefore often referred to as “feedforward damping control”).

  On the other hand, the vibration damping control when the wheel torque is changed due to a disturbance on the vehicle body is caused by a change in the state of the vehicle on the road surface (irregularity or foreign matter on the road surface, change in gradient or friction state). This is for suppressing fluctuations caused by fluctuations in the road surface reaction force and forces such as wind transmitted to the vehicle body as dynamic disturbances, and the disturbances becoming vibration or forcing forces. In such vibration suppression control, the action of the disturbance that becomes the vibration force or the vibration forcing force as described above eventually appears in the wheel torque. Therefore, as a specific control method, it actually acts on the wheel. The wheel torque estimated value estimated from the wheel torque value or the wheel speed is referred to, and the acceleration / deceleration request amount is compensated in order to remove or reduce the vibration component causing the vibration of the vehicle body in the wheel torque value. The operation of the driving device or braking device is controlled based on the compensated acceleration / deceleration request amount (therefore, actual wheel torque fluctuations are “feedback” to the braking / driving force control system that controls the wheel torque to control vibration. Often referred to as “feedback damping control”).

  In the case of the feedback damping control as described above, in principle, the wheel torque or the braking / driving for suppressing the disturbance or the vibration after the disturbance causing the vibration or the vibration to be suppressed due to the disturbance starts to occur. Force adjustment will be performed. Therefore, in order to satisfactorily suppress the vehicle body vibration, the time from the detection of the change in the wheel torque value to the occurrence of the change in the braking / driving force for canceling or suppressing the vibration forcing force (disturbance) or the vibration displacement ( The response time of the control is shortened as much as possible so that the change in the braking / driving force applied to the wheels can follow the change in the displacement (amplitude) of the vibration of the vehicle body. I need to be quick. However, in an actual vehicle device, there is a limit to the response speed of the braking / driving force of the driving device (engine or motor) or braking device to the signal processing speed or control command, and the control response time is made infinitely small. I can't do it. In other words, in the conventional feedback vibration suppression control in which control is executed after the occurrence of disturbance, the wheel torque is reduced from the occurrence of disturbance due to the limit of the control response time that can be shortened in the signal processing device or the drive device or braking device. Even if there is a request for further shortening the time until execution of the adjustment, such a request may not be answered, and there is a possibility that the adjustment of the wheel torque is delayed due to a change in the vibration displacement to be suppressed.

  Therefore, the inventor of the present invention is a vibration suppression control device of a type that executes vibration suppression control that suppresses vibration of the vehicle body by wheel torque control of the vehicle, and that vibration due to disturbance acting on the vehicle body is generated. Predicted from the running state of the vehicle traveling in front of the vehicle (preceding vehicle), so that when vibration due to disturbance occurs in the vehicle, the vibration intensity is not delayed without delay. A damping control device for a vehicle configured to execute the braking / driving force control is proposed. In the vibration damping control device, in short, the wheel speed or wheel rotation speed of the preceding vehicle, the engine rotation speed, the turbine rotation speed, or the transmission rotation speed (hereinafter referred to as “wheel speed or the like”). An information receiving unit that receives information representing a value, and estimates the wheel torque estimated value of the own vehicle using the information, and suppresses the amplitude of the vehicle body vibration (of the own vehicle) based on the wheel torque estimated value A vibration damping control unit is provided that calculates a wheel torque compensation component that compensates for the wheel torque and controls the wheel torque using the wheel torque compensation component. According to such a configuration, as in the conventional feedback control, the actual vehicle torque fluctuation due to the disturbance is not detected and the wheel torque compensation component is not calculated, but the vehicle is similar to the preceding vehicle in the future. It is possible to estimate the wheel torque of the host vehicle before the influence of the disturbance using the wheel speed representing the fluctuation of the wheel torque in the preceding vehicle under the assumption that the influence of the disturbance is received. Preparations for wheel torque compensation can be completed before the disturbance occurs (wheel torque disturbance preview control). Therefore, in an actual vehicle, it is expected that the problem that the execution of the control is delayed due to the limit of the control response time that can be shortened in the signal processing device, the driving device, or the braking device is expected to be solved.

  As described above, when information on the wheel speed of the preceding vehicle is used to estimate the future wheel torque of the host vehicle and the vibration suppression control is executed based on the estimated wheel torque, Even if the vehicle is affected by the same disturbance as the preceding vehicle, if the vehicle speed and tire diameter of the preceding vehicle are different from those of the host vehicle, the fluctuation amount of the wheel speed of the preceding vehicle differs between the two vehicles. It has been found that the torque compensation component may be different. For example, it has been experimentally found that when a vehicle travels on a protrusion on a certain road surface, the variation in wheel torque caused by the protrusion and the magnitude of the compensation component vary depending on the vehicle speed and the tire diameter. Therefore, as described above, when the vibration suppression control based on the fluctuation of the wheel torque of the own vehicle predicted from the response to the disturbance of the preceding vehicle is executed satisfactorily, the wheel torque compensation component is used in the preceding vehicle and the own vehicle. It is necessary to correct according to the difference in vehicle speed or tire diameter.

  Thus, an object of the present invention is to provide a vibration suppression control device for a vehicle that suppresses vibration of a vehicle body by controlling wheel torque or braking / driving force using information such as the wheel speed of the preceding vehicle. An object of the present invention is to provide a vibration damping control device modified so that an appropriate wheel torque compensation component can be calculated from information such as the wheel speed of a preceding vehicle even when the vehicle speed or the tire diameter is different from that of the host vehicle.

  According to the present invention, there is provided a vibration suppression control device for a vehicle that suppresses vehicle body vibrations by controlling wheel torque generated at a contact point between a vehicle wheel and a road surface. An information receiving unit that receives at least one of information representing a value of a wheel speed or a wheel rotational speed, an engine rotational speed, a turbine rotational speed, or a transmission rotational speed of the preceding vehicle from a preceding vehicle traveling in front of the vehicle; The wheel torque estimated value of the own vehicle is estimated using the above information, and the wheel torque compensation component for compensating the wheel torque of the own vehicle is calculated so as to suppress the amplitude of the vehicle body vibration based on the wheel torque estimated value. A vibration damping control unit that controls the wheel torque using the wheel torque compensation component, and the vibration damping control unit corrects the wheel torque compensation component based on the vehicle speed or wheel diameter of the host vehicle and the vehicle speed or wheel diameter of the preceding vehicle. Compensation It is achieved by a device which comprises a correction unit.

  In the above configuration, the vehicle body vibration to be suppressed is a vibration in which a mechanical disturbance appearing in the wheel torque becomes a vibration forcing force or a vibration generating force, and is canceled or reduced by adjusting the wheel torque. The vibration may be, for example, the pitch or bounce vibration of the vehicle body, the drive system vibration of the vehicle, or the shake vibration of the vehicle engine. The wheel torque control is typically control of drive output of a vehicle drive device (engine, motor, etc.). In this case, the wheel torque is controlled by adjusting drive output or drive torque or drive force. Will be. However, the wheel torque may be controlled by adjusting the longitudinal force on the wheel (force in the rotational direction around the axle) by the operation of the braking system device or the steering system device. In addition, the information receiving unit of the apparatus of the present invention may preferably be configured to receive information such as wheel speed from the preceding vehicle by inter-vehicle communication between the host vehicle and the preceding vehicle. Further, regarding the execution of wheel torque control in the above-described apparatus of the present invention, the disturbance to the vehicle is typically a road surface unevenness or a mechanical action such as a cross wind, a tail wind, or a head wind. Since it often occurs at a specific position on the route, the vibration suppression control unit is used when the vehicle reaches the position of the preceding vehicle when the information on the preceding vehicle used for calculating the wheel torque compensation component is generated. In addition, the wheel torque may be controlled so that the wheel torque compensation component calculated based on the wheel torque value estimated from the information is reflected on the wheel. In this case, at the same time as the disturbance occurs in the host vehicle, a wheel torque compensation component that cancels or reduces the action of the disturbance is generated in the wheel, so that a good vibration damping effect can be obtained. There is expected.

  In the apparatus of the present invention, as understood from the above description, the wheel torque compensation component calculated by the vibration suppression control unit using information such as the wheel speed of the preceding vehicle is used as the vehicle for controlling the wheel torque. When the control component is given as a control command to the braking / driving force generation device (engine / motor or braking device), the compensation component correction unit is based on the vehicle speed of the host vehicle and the vehicle speed of the preceding vehicle and / or the wheel of the host vehicle. The wheel torque compensation component is configured to be corrected based on the diameter and the wheel diameter of the preceding vehicle. Thereby, even if there is a difference in vehicle speed between the own vehicle and the preceding vehicle, or even if there is a difference in tire diameter between the own vehicle and the preceding vehicle, the deviation of the wheel torque compensation component due to these differences is corrected, It is expected that a good vibration damping action is achieved in the host vehicle.

  In the embodiment, in the correction of the wheel torque compensation component based on the vehicle speed, the control gain for the wheel torque compensation component is determined based on the vehicle speed of the host vehicle and the vehicle speed of the preceding vehicle, and the wheel torque compensation component is controlled. Wheel torque control may be executed by a value multiplied by the gain. Since the vehicle speed changes from moment to moment, the control gain may be determined as needed. More specifically, the compensation component correction unit is provided with a gain factor determination unit that determines a control gain factor of the wheel torque compensation component as a function of the vehicle speed. The gain factor determination unit corresponds to the vehicle speed of the host vehicle. The control gain for the wheel torque compensation component is determined on the basis of the control gain coefficient determined by the control parameter and the control gain coefficient determined by the gain coefficient determination unit corresponding to the vehicle speed of the preceding vehicle. The wheel torque may be controlled by a value multiplied by the torque compensation component. Here, the control gain coefficient is an amount representing the dependence of the magnitude of the compensation component on the vehicle speed, if necessary. Therefore, as described above, according to the method in which the control gain coefficients are determined separately for the preceding vehicle and the own vehicle, and the final control gain is determined based on the control gain coefficients, the preceding vehicle and the own vehicle Even if the vehicle is traveling at any vehicle speed, it can be corrected. In this case, the control gain coefficient is a value determined based on a wheel torque compensation component that suppresses the amplitude of vehicle body vibration given when the vehicle travels on a predetermined road surface at an arbitrary vehicle speed. Good.

  In the correction of the wheel torque compensation component based on the tire diameter, the control gain for the wheel torque compensation component is determined based on the wheel diameter of the host vehicle and the wheel diameter of the preceding vehicle, as in the case of the correction based on the vehicle speed. Wheel torque control may be executed by a value obtained by multiplying the wheel torque compensation component by the control gain. More specifically, the compensation component correction unit includes a gain coefficient determination unit that determines a control gain coefficient of the wheel torque compensation component as a function of the wheel diameter, and the control gain for the wheel torque compensation component is set to the wheel diameter of the host vehicle. Correspondingly, the control gain coefficient determined by the gain coefficient determination unit and the control gain coefficient determined by the gain coefficient determination unit corresponding to the wheel diameter of the preceding vehicle may be determined. The control gain coefficient in this case is also an amount representing the dependence of the compensation component on the wheel diameter, as in the case of the vehicle speed. According to the configuration in which the control gain coefficient is determined for each vehicle instead of the wheel diameter difference, the compensation component can be corrected for a vehicle having an arbitrary wheel diameter. The control gain coefficient may be a value determined based on a wheel torque compensation component that suppresses the amplitude of vehicle body vibration given when a vehicle having an arbitrary wheel diameter travels on a predetermined road surface.

  By the way, the wheel diameter is preferably given as one of specifications in each vehicle, and is an amount used in calculating the wheel speed and in other controls. Therefore, in principle, the wheel diameter of the host vehicle is grasped in advance by the control device, and the wheel diameter of the preceding vehicle can be acquired by inter-vehicle communication or the like. That is, while the vehicle is traveling, the control gain, which is a function of the wheel diameter, can be calculated by obtaining the wheel diameter of the preceding vehicle from the inter-vehicle communication or the like. However, in a vehicle, the tire is often changed by the user and the wheel diameter may be changed. Therefore, the wheel diameter of the host vehicle and the wheel diameter of the preceding vehicle may be estimated from the respective wheel speeds. Specifically, when the absolute vehicle speed is known, the wheel diameter may be calculated based on the wheel rotational speed and the absolute vehicle speed, or the primary rotation component detected by frequency analysis of the wheel speed. The wheel diameter may be calculated from the frequency and the absolute vehicle speed. The determination of the wheel diameter for determining the control gain here is for detecting the difference in the size of the compensation component between the host vehicle and the preceding vehicle. In consideration of the fact that it varies depending on the vehicle speed of the vehicle, the wheel diameter of each vehicle is preferably executed when the vehicle speeds of the two vehicles are equal (error due to the difference in vehicle speed is reduced). Therefore, preferably, the control gain for the wheel torque compensation component may be determined when the difference between the vehicle speed of the vehicle and the vehicle speed of the preceding vehicle is substantially the same.

  In general, the present invention relates to a vibration damping control device that detects or estimates the occurrence of a disturbance acting on a vehicle from the state of a preceding vehicle and compensates for wheel torque against the disturbance. If there is a difference in the vehicle speed and / or tire diameter, the assumption that the state of the preceding vehicle is the future state (for example, several seconds later) of the host vehicle is not necessarily satisfied. It can be said that it is a thing to deal with. Since the vibration damping control that is the subject of the present invention is executed by manipulating the braking / driving force of the vehicle with the wheel torque, if the wheel torque compensation component is excessive or insufficient, the vibration suppression control effect In some cases, not only worsening but also anti-phase vibrations may occur. According to the present invention, occurrence of such a problem is reduced.

  As described above, the correction of the wheel torque compensation component with respect to the vehicle speed and the correction of the wheel torque compensation component with respect to the wheel diameter are determined by substantially the same processing except that the parameters for determining the control gain coefficient of each vehicle are different. It should be understood that it can be done. The present invention mainly corrects the dependency of the magnitude of the compensation component on the vehicle speed or wheel diameter. However, when there is a difference in the magnitude of the compensation component between the preceding vehicle and the host vehicle due to other factors. However, it should be understood that correction can be made in the same manner as described above.

  Other objects and advantages of the present invention will become apparent from the following description of preferred embodiments of the present invention.

  The present invention will now be described in detail with reference to a few preferred embodiments with reference to the accompanying drawings. In the figure, the same reference numerals indicate the same parts.

Diagram 1 of the apparatus is a vehicle such as an automobile in which the preferred embodiment of the vibration damping control device is mounted of the present invention is schematically shown. In the figure, the vehicle 10 having the left and right front wheels 12FL and 12FR and the left and right rear wheels 12RL and 12RR is driven in the normal manner according to the depression of the accelerator pedal 14 by the driver. A drive device 20 that generates torque is mounted. In the illustrated example, the driving device 20 transmits driving torque or rotational driving force from the engine 22 to the rear wheels 12RL and 12RR via the torque converter 24, the automatic transmission 26, the differential gear device 28, and the like. It is configured as follows. However, the drive device may be an electric drive in which an electric motor is used instead of the engine 22 or a hybrid drive device having both an engine and an electric motor. The vehicle may be a four-wheel drive vehicle or a front wheel drive vehicle. Although not shown for the sake of simplicity, the vehicle 10 is provided with a braking system device that generates a braking force on each wheel and a steering device for controlling the steering angle of the front wheels or the front and rear wheels, as in a normal vehicle. It is done.

The operation of the driving device 20 is controlled by the electronic control device 50. The electronic control unit 50 may include a microcomputer having a CPU, a ROM, a RAM, and an input / output port device, which are connected to each other by a bidirectional common bus, and a driving circuit. The electronic control unit 50 includes a signal Vwi (i = FL, FR, RL, RR) representing a wheel speed from a wheel speed sensor 30i (i = FL, FR, RL, RR) mounted on each wheel, and G Signals such as the longitudinal acceleration α of the vehicle from the sensor 32, the rotational speed ne of the engine, the rotational speed no of the transmission, and the accelerator pedal depression amount θa from the sensors provided in each part of the vehicle are input. In addition to the above, various detection signals for obtaining various parameters necessary for various controls to be executed in the vehicle of the present embodiment, for example, each of the load sensors that may be arbitrarily provided on each wheel It should be understood that a signal representing wheel load, engine output shaft torque, etc. may be input. Furthermore, the vehicle 10 communicates with a vehicle-to-vehicle communication system 70 and a GPS artificial satellite that can communicate with each other any information such as a running / driving state with a vehicle traveling in front of or around the vehicle 10. And a GPS device (car navigation system) 72 for acquiring various information such as the position information of the own vehicle and / or a detector for measuring a relative distance and a relative speed with respect to a stationary object, a preceding vehicle, etc. in front of the vehicle (Millimeter wave sensor (FMCW method), radar device, sonar device, etc.) 74 may be provided, and the data output of these devices is also transmitted to the electronic control device 50. The inter-vehicle communication system 70, the GPS device 72, or the detector 74 may be of any known type, from these systems or devices for previewing wheel torque disturbances in the control of the present invention and Various information used for obtaining the absolute vehicle speed (vehicle speed relative to the road surface) Vs of the vehicle used there, that is, the traveling state of the preceding vehicle such as the position of the preceding vehicle, vehicle speed, wheel speed, gear stage, gear ratio, etc. It is assumed that the value / signal indicating the vehicle speed and the vehicle speed of the host vehicle can be used as appropriate. The vehicle speed of the host vehicle and the vehicle speed of the preceding vehicle may be determined by any method such as referring to the wheel speed of the driven wheel, but may be acquired by any of the following methods.
(A) Detection by GPS information: The absolute vehicle speed Vs is calculated from the time differential value of the position information of each vehicle from the GPS device 72.
(B) Absolutely based on the relative speed of the sonar device, radar device 74, etc. (for example, FMCW radar device employing a millimeter wave sensor) or a stop in front of the host vehicle, a road surface marker, and a preceding vehicle acquired by a video camera image. The vehicle speed Vx is calculated (when the relative speed with the preceding vehicle is detected, the vehicle speed of the preceding vehicle is acquired by inter-vehicle communication with the preceding vehicle).
(C) The absolute vehicle speed Vs is determined from the time integral value from the start of the vehicle in the longitudinal acceleration of the G sensor or the like.

  The vibration damping control device of the present invention is realized in the electronic control device 50 described above. FIG. 2 shows the internal configuration of an embodiment of such an electronic control device 50 in the form of a control block.

  Referring to FIG. 2, an electronic control unit 50 includes a drive control unit 50a that controls the operation of the engine, a braking control unit 50b that controls the operation of a braking unit (not shown), and a known electronic vehicle unit. You may comprise from the various control apparatuses (not shown) with which a control apparatus is equipped. It is understood that the configuration and operation of various control devices such as a drive control device including a vibration suppression control device are realized by processing operations of the CPU and the like in the electronic control device 50 during operation of the vehicle. Should.

  As shown in the figure, the braking control device 50b includes a pulse-type electric power that is sequentially generated every time the wheel rotates by a predetermined amount from the wheel speed sensor 30i (i = FR, FL, RR, RL) of each wheel. The wheel rotational speed ω is calculated by measuring the time interval between arrival of such sequentially input pulse signals, and the wheel radius value r · ω is multiplied by the wheel rotational speed r. Is calculated. Then, the wheel speed value r · ω is transmitted to the drive control device 50a and used for calculation of the estimated wheel torque value in order to execute vibration suppression control which will be described in detail later. The calculation from the wheel rotation speed to the wheel speed may be performed by the drive control device 50a. In this case, the wheel rotation speed is given from the braking control device 50b to the drive control device 50a.

  As a basic configuration, the drive control device 50a includes a required drive torque determining unit 51 that determines a required drive torque value of the engine requested by the driver based on the accelerator pedal depression amount θa from the accelerator pedal sensor, and a wheel torque ( Feedforward damping control unit 52a and feedback damping control which calculates a requested driving torque compensation component for executing pitch / bounce vibration damping control of the vehicle body by driving torque) control and compensates (corrects) the requested driving torque value Based on the required drive torque value compensated by the unit 52b and the two vibration suppression control units, a control command for each part of the engine is generated in an arbitrary known manner, and the corresponding control is performed. The engine control command part 53 to be transmitted to the device is included. [The control command includes a target throttle opening for a gasoline engine, a target fuel injection amount for a diesel engine, a target current amount for a motor, and the like. ]

  In such a basic configuration, the required drive torque determination unit 51 determines the required drive torque value from the accelerator pedal depression amount θa (and / or a request by any automatic travel control) by any known method. It's okay. As shown in the figure, the feedforward vibration suppression control unit 52a receives the required drive torque value (before compensation) determined by the required drive torque determination unit 51, and performs a required drive torque value ( A compensation component that reduces or cancels a vibration component that may cause pitch bounce vibration in the vehicle body before compensation) is calculated. The compensation component is superimposed on the required driving torque value (before compensation) in the adder a1. [The feedforward vibration suppression control unit further calculates a compensation component for suppressing the pitch bounce vibration caused by the change in the wheel torque generated in the wheel by the brake operation or the steering operation by the driver. It may be. In that case, as indicated by the dotted line in the figure, an estimated wheel torque value based on the brake operation amount or the steering operation amount is input to the feedforward vibration suppression control unit, and is the same as the required drive torque value. To calculate a compensation component. ]

  On the other hand, the feedback vibration suppression control unit 52b receives an estimated value of the wheel torque estimated from the wheel speed r · ω by the wheel torque estimator 52c in a mode described in detail later, and uses the estimated value of the wheel torque. A compensation component that reduces or cancels a vibration component that can cause pitch bounce vibration in the vehicle body, that is, a disturbance vibration component in the wheel torque is calculated. The compensation component of the feedback vibration damping control unit is superimposed on the required drive torque value by the adder a2 via the output delay unit 54a and the control gain multiplier 52d described later.

  In addition to the basic configuration described above, the electronic control device incorporating the vibration suppression control device of the present invention has a configuration for previewing the preceding vehicle of the wheel torque disturbance, that is, in the column “Disclosure of the Invention”. As described above, the occurrence of vibration due to disturbance acting on the vehicle body is predicted from the traveling state of the vehicle traveling in front of the own vehicle (preceding vehicle), so that the vibration due to disturbance is generated in the own vehicle. There is provided a configuration for executing the braking / driving force control for damping without delaying the change in the vibration intensity when it occurs. That is, in the vibration suppression control apparatus of the present invention, when executing the preceding vehicle preview control, the vibration suppression control for the wheel torque disturbance is performed based on the fluctuation of the wheel torque estimated from the wheel speed of the own vehicle. Instead of this, it is configured to be executed using fluctuations in wheel torque estimated from the wheel speed or the like of the preceding vehicle. As a configuration for the preceding vehicle preview control, specifically, an information receiving unit 70 (an inter-vehicle communication system) that receives information representing the wheel speed value from the preceding vehicle and gives the wheel speed value to the wheel torque estimator 52c. ) And on the basis of information from the inter-vehicle communication system 70, the GPS device 72 and / or the on-vehicle radar device or the sonar device 74, it is determined whether or not the vehicle is following the trajectory of the preceding vehicle. The wheel torque compensation component calculated by the preview determination unit 54b for determining whether or not the preceding vehicle preview control can be executed, and the feedback vibration damping control unit 52b based on the preceding vehicle wheel speed when the preceding vehicle preview control is executed. Output delay device 54a for measuring the output timing of the vehicle, and wheel torque due to a difference in vehicle speed and / or wheel diameter between the preceding vehicle and the own vehicle when the preceding vehicle preview control is executed. A control gain 54c for correcting the amount of deviation between 償成 content is provided. The detailed configuration and operation of each control unit for the preceding vehicle preview control will be described later.

  Further, in the vibration suppression control device, a low-pass filter (LPF), a high-pass filter (HPF) or a band is used in order to avoid an unnecessary vibration component being input to the wheel torque estimator 52c. A pass filter (BPF) 55 may be provided. LPF processing mainly includes vibration components that deviate from the resonant frequency of pitch / bounce vibration (usually about 1 to 2 Hz) and vibration components that are not true wheel torque vibrations (sensor errors, artifacts, etc.). Used to remove. The HPF process is used to remove a fluctuation component caused by the driver's accelerator or brake operation in the preceding vehicle, particularly when the wheel speed of the preceding vehicle is used.

  In this embodiment, the wheel torque is controlled by controlling the driving torque transmitted from the driving device to the wheel, and the wheel torque is further controlled by operating the braking device or the steering device. It should be understood that it may be adapted.

Device Operation (i) Pitch / Bounce Vibration Suppression Control In the above configuration, the pitch / bounce vibration suppression control by the feedforward vibration suppression control unit 52a and the feedback vibration suppression control unit 52b in FIG. May be done.

(Principle of vibration suppression control)
In the vehicle, when the driving device is activated based on the driving request of the driver and the wheel torque fluctuates, the vertical position of the center of gravity Cg of the vehicle body in the vehicle body 10 as illustrated in FIG. The bounce vibration in the direction (z direction) and the pitch vibration in the pitch direction (θ direction) around the center of gravity of the vehicle body can occur. In addition, if a force or torque (disturbance) acts on wheels due to changes in road surface conditions or wind while the vehicle is running, the disturbance is transmitted to the vehicle, and vibrations in the bounce direction and pitch direction are also generated in the vehicle body. obtain. Therefore, in the pitch / bounce vibration damping control exemplified here, a motion model of the pitch / bounce vibration of the vehicle body is constructed, and the required drive torque (value converted to wheel torque) or current Vehicle wheel displacement z and θ and their rate of change dz / dt and dθ / dt when the estimated wheel torque value (or the future wheel torque estimated from the preceding vehicle wheel speed) is input, that is, the state of the vehicle body vibration The driving torque of the driving device (engine) is adjusted so that the state variable obtained from the model converges to 0, that is, the pitch / bounce vibration is suppressed (the required driving torque is corrected). ) Note that the adjustment amount of the drive torque calculated when the required drive torque is input is a compensation component from the feedforward vibration suppression control unit, and the adjustment amount of the drive torque calculated when the current wheel torque is input is This is a compensation component from the feedback damping control unit.

ここに於いて、Ｌｆ、Ｌｒは、それぞれ、重心から前輪軸及び後輪軸までの距離であり、ｒは、車輪半径であり、ｈは、重心の路面からの高さである。なお、式（１ａ）に於いて、第１、第２項は、前輪軸から、第３、４項は、後輪軸からの力の成分であり、式（１ｂ）に於いて、第１項は、前輪軸から、第２項は、後輪軸からの力のモーメント成分である。式（１ｂ）に於ける第３項は、駆動輪に於いて発生する車輪トルクＴが車体の重心周りに与える力のモーメント成分である。 Thus, first, as a dynamic motion model in the bounce direction and the pitch direction of the vehicle body in the vibration suppression control, for example, as shown in FIG. 3B, the vehicle body is a rigid body S having a mass M and an inertia moment I. It is assumed that the rigid body S is supported by a front wheel suspension having an elastic modulus kf and a damping rate cf, and a rear wheel suspension having an elastic modulus kr and a damping rate cr (vehicle body sprung vibration model). In this case, the motion equation in the bounce direction and the motion equation in the pitch direction of the center of gravity of the vehicle body are expressed as the following Equation 1.

Here, Lf and Lr are distances from the center of gravity to the front wheel shaft and the rear wheel shaft, respectively, r is a wheel radius, and h is a height of the center of gravity from the road surface. In Equation (1a), the first and second terms are components of force from the front wheel shaft, and the third and fourth terms are components of force from the rear wheel shaft. In Equation (1b), the first term Is the moment component of the force from the front wheel shaft, and the second term is the force from the rear wheel shaft. The third term in the equation (1b) is a moment component of the force that the wheel torque T generated in the drive wheel gives to the periphery of the center of gravity of the vehicle body.

であり、行列Ａの各要素a1-a4及びb1-b4は、それぞれ、式（１ａ）、（１ｂ）のｚ、θ、ｄｚ／ｄｔ、ｄθ／ｄｔの係数をまとめることにより与えられ、
a1=-(kf+kr)/M、a2=-(cf+cr)/M、
a3=-(kf・Lf-kr・Lr)/M、a4=-(cf・Lf-cr・Lr)/M、
b1=-(Lf・kf-Lr・kr)/I、b2=-(Lf・cf-Lr・cr)/I、
b3=-(Lf²・kf+Lr²・kr)/I、b4=-(Lf²・cf+Lr²・cr)/I
である。また、ｕ(t)は、
ｕ(t)＝Ｔ
であり、状態方程式（２ａ）にて表されるシステムの入力である。従って、式（１ｂ）より、行列Ｂの要素p1は、
p1=h/(I・r)
である。 The above formulas (1a) and (1b) are expressed as (linear) as shown in the following formula (2a) with the vehicle body displacements z and θ and their change rates dz / dt and dθ / dt as the state variable vector X (t). It can be rewritten in the form of a system state equation.
dX (t) / dt = A · X (t) + B · u (t) (2a)
Here, X (t), A, and B are respectively

And each element a1-a4 and b1-b4 of the matrix A is given by combining the coefficients of z, θ, dz / dt, dθ / dt in the equations (1a) and (1b), respectively.
a1 =-(kf + kr) / M, a2 =-(cf + cr) / M,
a3 =-(kf ・ Lf-kr ・ Lr) / M, a4 =-(cf ・ Lf-cr ・ Lr) / M,
b1 =-(Lf ・ kf-Lr ・ kr) / I, b2 =-(Lf ・ cf-Lr ・ cr) / I,
b3 =-(Lf ²・ kf + Lr ²・ kr) / I, b4 =-(Lf ²・ cf + Lr ²・ cr) / I
It is. U (t) is
u (t) = T
And is an input of the system represented by the state equation (2a). Therefore, from equation (1b), the element p1 of the matrix B is
p1 = h / (I ・ r)
It is.

In the equation of state (2a)
u (t) = − K · X (t) (2b)
Then, the equation of state (2a) is
dX (t) / dt = (A-BK) .X (t) (2c)
It becomes. Accordingly, the initial value X ₀ (t) of X (t) is set as X ₀ (t) = (0,0,0,0) (assuming that there is no vibration before torque is input). ), The gain that converges the magnitude of X (t), that is, the displacement in the bounce direction and the pitch direction and its time change rate, to 0 when the differential equation (2c) of the state variable vector X (t) is solved When K is determined, a torque value u (t) for suppressing pitch bounce vibration is determined. A value obtained by converting the torque value u (t) into a unit of engine driving torque is a compensation component given to the engine by vibration suppression control.

The gain K can be determined by using a so-called optimal regulator theory. According to this theory, a quadratic evaluation function J = 1/2 · ∫ (X ^T QX + u ^T Ru) dt (3a)
(Integral range is 0 to ∞)
When the value of is the minimum, the matrix K that minimizes the evaluation function J by the stable convergence of X (t) in the state equation (2a) is
K = R ⁻¹・ B ^T・ P
It is known to be given by Where P is the Riccati equation
^{-dP / dt = A T P +} PA + Q-PBR -1 B T P
Is the solution. The Riccati equation can be solved by any method known in the field of linear systems, which determines the gain K.

などと置いて、式（３ａ）に於いて、状態ベクトルの成分のうち、特定のもの、例えば、ｄｚ／ｄｔ、ｄθ／ｄｔ、のノルム（大きさ）をその他の成分、例えば、ｚ、θ、のノルムより大きく設定すると、ノルムを大きく設定された成分が相対的に、より安定的に収束されることとなる。また、Ｑの成分の値を大きくすると、過渡特性重視、即ち、状態ベクトルの値が速やかに安定値に収束し、Ｒの値を大きくすると、消費エネルギーが低減される。 Q and R in the evaluation function J and Riccati equation are a semi-positive definite symmetric matrix and a positive definite symmetric matrix, respectively, which are arbitrarily set, and are weight matrices of the evaluation function J determined by the system designer. For example, in the case of the motion model considered here, Q and R are

In Equation (3a), a specific one of the components of the state vector, for example, the norm (magnitude) of dz / dt, dθ / dt, and the other components, for example, z, θ If the value is set larger than the norm of, the component having the larger norm is converged relatively stably. Further, when the value of the Q component is increased, the transient characteristics are emphasized, that is, the value of the state vector quickly converges to a stable value, and when the value of R is increased, the energy consumption is reduced.

ここに於いて、xf、xrは、前輪、後輪のばね下変位量であり、mf、mrは、前輪、後輪のばね下の質量である。式（４ａ）−（４ｂ）は、ｚ、θ、xf、xrとその時間微分値を状態変数ベクトルとして、図３（Ｂ）の場合と同様に、式（２ａ）の如き状態方程式を構成し（ただし、行列Ａは、８行８列、行列Ｂは、８行１列となる。）、最適レギュレータの理論に従って、状態変数ベクトルの大きさを０に収束させるゲイン行列Ｋを決定することができる。 As a dynamic motion model in the bounce direction and the pitch direction of the vehicle body, for example, as shown in FIG. 3C, in addition to the configuration in FIG. 3B, the spring elasticity of the front and rear tires A model that takes into account the above (vehicle body sprung / lower vibration model) may be employed. Assuming that the front and rear tires have the respective elastic moduli ktf and ktr, the motion equation in the bounce direction and the motion equation in the pitch direction of the center of gravity of the vehicle body are as understood from FIG. The following equation 4 is expressed.

Here, xf and xr are unsprung displacement amounts of the front and rear wheels, and mf and mr are unsprung masses of the front and rear wheels. Equations (4a)-(4b) form a state equation as shown in Equation (2a) using z, θ, xf, xr and their time differential values as state variable vectors, as in FIG. 3B. (However, the matrix A has 8 rows and 8 columns and the matrix B has 8 rows and 1 column.) According to the theory of the optimal regulator, the gain matrix K that converges the magnitude of the state variable vector to 0 can be determined. it can.

(Configuration of vibration control unit)
The control configurations of the feedforward damping control unit 52a and the feedback damping control unit 52b for calculating the compensation component U for the pitch / bounce damping control are shown in FIGS. 4A and 4B, respectively. ing. First, referring to FIG. 4A, in the feedforward vibration suppression control unit 52a of FIG. 2, after the required drive torque value from the required drive torque determining unit 51 is converted into the wheel torque Two, The wheel torque input T is input to the motion model (the estimated wheel torque value corresponding to the brake operation amount or the steering operation amount may also be input). In the motion model, the torque input value Two is used. The state variable vector X (t) is calculated by solving the differential equation of Expression (2a). Next, a value u (t) obtained by multiplying the state vector X (t) by the gain K determined to converge the state variable vector X (t) to 0 or the minimum value as described above is calculated. t) is converted into a compensation component U (t) in units of engine driving torque and transmitted to the adder a1. Then, in the adder a1, the compensation component U (t) is subtracted from the required drive torque value. As can be seen from equations (1a) and (1b), the body pitch-bounce vibration system is a resonant system, and for any input, the value of the state variable vector is essentially Only frequency components in a band having a certain spectral characteristic with the frequency (about 1 to 5 Hz) as the center are provided. Thus, by configuring so that U (t) is subtracted from the required driving torque, the component of the natural frequency of the required driving torque, that is, the component causing the pitch bounce vibration in the vehicle body is reduced or eliminated. Thus, pitch bounce vibrations in the vehicle body are suppressed.

  The configuration of the feedback vibration suppression control unit 52b shown in FIG. 4B is that the wheel torque currently generated in the wheel (estimated value) or the preceding vehicle preview control as described later is advanced. Except for the fact that a (future) wheel torque estimated value Tw estimated based on the vehicle wheel speed or the like is input as the wheel torque input T, it is the same as the feedforward vibration suppression control unit. However, when the wheel torque Tw is input, a feedback control gain FB (gain for adjusting the balance of contribution between the driver requested wheel torque Tw0 and the estimated wheel torque value Tw in the motion model) is multiplied. It may be. Further, as shown in FIG. 2, the compensation component that is the output of the feedback damping control unit is superimposed on the required drive torque by the adder a2 via the output delay unit 54a and the control gain adjuster 52d, The engine output is adjusted to suppress pitch bounce vibration caused by wheel torque disturbance.

(ii) Estimation of wheel torque Since the value of wheel torque input in FIG. 4B reflects the effect of disturbance, this wheel torque is ideally applied to each wheel. Although a sensor may be provided and actually detected, it is difficult to provide a torque sensor on each wheel of a normal vehicle. Therefore, in the illustrated example, the wheel torque estimated value estimated by the wheel torque estimator 52c (FIG. 2) from other detectable values in the running vehicle is used as the disturbance input of the wheel torque. The wheel torque estimated value Tw is typically obtained by using a wheel rotational speed ω obtained from a wheel speed sensor of a driving wheel or a time derivative of a wheel speed value r · ω,
Tw = M · r ² · dω / dt (5)
Can be estimated. Here, M is the mass of the vehicle, and r is the wheel radius. [If the sum of the driving forces generated at the contact points of the driving wheels on the road surface is equal to the overall driving force MG (G is acceleration) of the vehicle, the wheel torque Tw is
Tw = M · G · r (5a)
Given in The acceleration G of the vehicle is obtained from the differential value of the wheel speed r · ω,
G = r · dω / dt (5b)
Therefore, the wheel torque is estimated as shown in Equation (5). Note that the estimated wheel torque value is not estimated from the wheel speed, but from the rotational speed of the rotating shaft of the drive system operatively connected to the drive wheels, such as the engine rotational speed, the transmission rotational speed, and the turbine rotational speed. It may be. When the rotational speed ne of the output shaft of the engine or motor of the driving device is used, the wheel rotational speed of the driving wheel is
ωe = ne x transmission (transmission) gear ratio x differential (differential gear) gear ratio (6)
Given by. When using the rotational speed no of the output shaft of the transmission,
ωo = no x differential gear ratio (7)
Given by. Then, the estimated value of the wheel rotational speed ω of the drive wheel in Expression (6) or (7) is substituted into Expression (5), and the estimated wheel torque value is calculated.

  At the time of execution of the preceding vehicle preview control described below, when the wheel torque is estimated from the wheel speed of the preceding vehicle, the wheel rotational speed ω is calculated from the wheel speed transmitted from the preceding vehicle, and the wheel diameter is The value of the own vehicle is used. Therefore, in order to obtain the wheel rotation speed from the preceding vehicle wheel speed, the value of the wheel diameter is also acquired from the preceding vehicle. Further, when the wheel torque is estimated from the engine rotational speed, transmission rotational speed, and turbine rotational speed transmitted from the preceding vehicle, values such as a transmission gear ratio and a differential gear ratio are also acquired.

(Iii) Preceding Vehicle Preview Control Referring to FIG. 5A, as shown in FIG. 5A, at the position of a distance L in front of the host vehicle (strictly, the distance between driving wheels). When the preceding vehicle is traveling, if the wheel torque changes due to road surface unevenness or the like in the preceding vehicle, the wheel that the host vehicle takes after time τ _movement (= L / Vs: Vs is the vehicle speed of the host vehicle). When reaching the position where the torque fluctuation has occurred, it is expected that the wheel torque will also fluctuate due to similar unevenness of the road surface in the host vehicle. That is, generally speaking, it is possible to predict that the disturbance that is actually acting on the preceding vehicle will act on the own vehicle in the future, or that the state of the preceding vehicle is the future state of the own vehicle. Therefore, in the preceding vehicle preview control, on the assumption that the disturbance that acts on the vehicle in the future has already been applied to the preceding vehicle traveling ahead of the own vehicle, inter-vehicle communication with the preceding vehicle, the preceding vehicle, etc. The position and wheel speed of the preceding vehicle are obtained using information technology or intelligence technology of the vehicle that has been rapidly developing in recent years, such as a radar or sonar device that detects relative distance and speed with GPS, and GPS. By predicting the occurrence of a disturbance acting on the host vehicle from fluctuations in wheel speed, etc., before the host vehicle reaches the position where the disturbance occurs, it can act as an excitation force of the disturbance according to the timing of the disturbance or Control of wheel torque or braking / driving force is executed so as to suppress vibration caused by the vibration (FIG. 5B).

  In the preceding vehicle preview control, first, the preview determination unit 54b uses the inter-vehicle communication system (preceding vehicle information receiving unit) 70, the GPS device 72, the radar or sonar device 74 while the vehicle is traveling. It is determined from the acquired information whether there is a preceding vehicle and whether the preceding vehicle preview control as described above is permitted. When execution of the preceding vehicle preview control is determined, the information is switched to the wheel torque estimator 52c, the output switching unit 52e, the output delay unit 52a provided on the output side of the feedback damping control unit, and the feedback control. This is transmitted to each of the control gain adjusters 54c for adjusting the magnitude of the control gain of the control gain multiplier 52d of the vibration control unit, and the preceding vehicle preview control is executed. Hereinafter, a specific embodiment of the preceding vehicle preview control will be described.

(A) Precedence Car Preview Control Executability Judgment—Configuration and Operation of Preview Judgment Unit The preceding car preview control execution feasibility judgment may be executed by the preview judgment unit 54b as described above. FIG. 6 shows the operation of the preview determination unit in the form of a flowchart. With reference to the figure, the preview determination unit first determines whether or not there is a preceding vehicle (step 100) as illustrated in FIG. If present, whether or not the vehicle is following the trail of the preceding vehicle and / or the phase of the wheel speed of the own vehicle is the wheel of the preceding vehicle when the preceding vehicle is at the position of the own vehicle. It is detected whether or not it substantially matches the speed phase (step 120). Then, if it is determined that the host vehicle is following the track of the preceding vehicle and / or the phase of the wheel speeds of the host vehicle and the preceding vehicle match, it is determined that preview is possible (step) 130) Execution of preview control is instructed (step 140). On the other hand, when it is determined that the preceding vehicle does not exist or the preview is not possible even if the preceding vehicle is present, non-execution or cancellation of the preview control is instructed (step 110).

  The presence / absence of the preceding vehicle in step 100 may be executed by a known determination method of any type, for example, information from the GPS device 72 or the vehicle-mounted radar or sonar device 74. Such a determination may be performed simultaneously with the determination in step 120.

  The detection of whether or not the vehicle in step 120 follows the trajectory of the preceding vehicle may be the same as the detection method used in LKA or the like. Alternatively, if the preceding vehicle is equipped with a GPS device, the position coordinates of the own vehicle are determined from the position coordinates of the preceding vehicle by comparing the position coordinates of the preceding vehicle with the position coordinates of the own vehicle from the information of the GPS device. In the case where it coincides with the trajectory, the vehicle may be detected or determined as following the preceding vehicle.

Further, in step 120, instead of or together with the determination of the coincidence of the trajectory between the preceding vehicle and the own vehicle, the phase of the wheel speed of the own vehicle is the wheel when the preceding vehicle is at the position of the own vehicle. Detection of whether or not the speed phase is substantially the same, that is, the phase difference between the wheel speeds may be executed. FIG. 7A shows the processing for detecting the wheel speed phase difference in the form of a control block diagram. Passing with reference to the drawing, first, the preceding vehicle wheel speed, considering that the preceding vehicle is traveling ahead by also _moving time τ from the vehicle, the preceding vehicle wheel speed value a1 is the delayer Is done. The delay unit may be configured to output its input with a delay of τ _movement = L / Vs and output the wheel when the preceding vehicle is at the current position of the host vehicle. (The delay time here does not depend on the vehicle speed of the preceding vehicle because the own vehicle arrives at the position where the preceding vehicle has transmitted a signal.) More precisely, the delay time may be a value obtained by subtracting the time τ _transmission required for transmission / reception of wheel speed information from the preceding vehicle, τ _movement- τ _{transmission,} as will be described later.

  Thus, when the time of the wheel speeds of the own vehicle and the preceding vehicle is adjusted, the wheel speeds of both are subjected to BPF processing, and a fluctuation component in the wheel speed is extracted from the wheel speed value (FIG. 7 ( B)). Here, the components to be removed are a DC component (component corresponding to an average value) and a noise component in the wheel speed value. The reason why the DC component is removed is that the vehicle speed may be different between the preceding vehicle and the host vehicle. And the fluctuation component which permeate | transmitted BPF process of both wheel speeds is each transmitted to a zero point detector. When detecting that the value of the fluctuation component has changed from a negative value to a positive value, that is, that the fluctuation component has passed the zero point, the zero point detector provides a signal indicating that to the timer. The timer starts timing in response to detection of the zero point passing of either the own vehicle wheel speed or the preceding vehicle wheel speed, and stops timing in response to detection of the other zero point passing, The time measurement result Δt is output. Thus, when the time interval Δt for passing the zero point is smaller than the predetermined value to, the phase difference between the wheel speeds of the own vehicle and the preceding vehicle is small as shown in the right diagram of FIG. 7B (amplitude). May be different), it is detected that the phases of the wheel speeds of the two are substantially the same. The predetermined value to may be appropriately set experimentally or theoretically.

  Thus, in step 120, the own vehicle travels following the trajectory of the preceding vehicle, or the phase of the wheel speeds of the own vehicle and the preceding vehicle (when both are in the same position) are approximately the same. In this case, as already mentioned, it is determined in step 130 that preview is possible, and execution of control in step 140 is instructed. In step 140, first, the preview determination unit 54b sets the input switching unit 52e so that the wheel speed of the preceding vehicle from the preceding vehicle information receiving unit 70 is input to the wheel torque estimator 52c ( Figure 2). Thereby, the wheel torque estimator 52c calculates the wheel torque estimated value as described above using the wheel speed of the preceding vehicle, and the value is transmitted to the feedback vibration suppression control unit 52b. Then, the feedback damping control unit 52b calculates a wheel torque compensation component using the input wheel torque estimated value. Also, the preview determination unit 54b transmits a signal indicating that preview control is executed to the output delay unit 54a and the control gain adjuster 54c, whereby the output delay unit 54a and the control gain adjuster 54c , Each will operate in the manner described below.

  On the other hand, if there is no preceding vehicle, or there is a preceding vehicle, but the vehicle does not follow the trajectory of the preceding vehicle, or if the phase difference between the two wheel speeds is large, or the preceding vehicle switches to preview control. When necessary information cannot be acquired and preview control cannot be executed, in step 110, the preview determination unit 54b performs preview control on the input switching unit 52e, the output delay unit 54a, and the control gain adjuster 54c. A signal indicating that is not executed. In this case, the input switching unit 52e may switch the input to the wheel torque estimator 52c to the wheel speed of the host vehicle or block the input itself.

(B) Anti-vibration control during execution of preceding vehicle preview control-configuration and operation of output delay device As described above, the disturbance generated in the preceding vehicle is
τ _movement = L / Vs (8)
It is presumed that it occurs in the host vehicle after the time given by Therefore, generally speaking, in the host vehicle, the wheel torque compensation component is realized in the wheel torque after the τ _movement time after the occurrence or detection of the wheel speed from the preceding vehicle. By giving the control command, it is expected that the wheel torque is compensated in accordance with the occurrence of the disturbance in the host vehicle, and the vibration suppression is satisfactorily achieved. Therefore, in the control device of the present invention, the wheel torque compensation component calculated using the wheel speed or the like from the preceding vehicle is sent to the output delay unit 54a, and when the preceding vehicle preview control is executed, The delay unit 54a delays the received wheel torque compensation component by the control delay time τ _delay determined by the following mode so that the realization time of the wheel torque compensation component coincides with the occurrence of the disturbance, and the engine control command determination unit 53 Send to.

FIG. 5B illustrates the time from when the value of wheel speed or the like is generated (detected) in the preceding vehicle until the wheel torque control is achieved in the host vehicle, and the control delay time τ. An example of time to be taken into account in determining the _delay is shown. As understood from the figure, in the time τ _movement from the occurrence of the wheel speed or the like from the preceding vehicle to the realization of the wheel torque compensation component, the time τ required for information transmission / reception is _{transmitted from} the received information. Time τ _{signal processing} for calculating the wheel torque compensation component, and time τ _response time from when the control command is given to the drive device (engine, etc.) until the required drive torque or wheel torque of the control command is realized Are required (ie, these times are spent). Therefore, in order to realize the wheel torque compensation component in accordance with the occurrence of disturbance in the own vehicle, the output delay unit 54a has a control delay time obtained by subtracting the time required for the processing from the time τ _movement. τ _delay , ie
τ _delay = τ _movement −τ _transmission −τ _{signal processing} −τ _response (9)
The transmission of the wheel torque compensation component to the engine control command determination unit is delayed by the time given by

Regarding the time deducted from the above time τ _movement , first, the transmission / reception time τ _transmission is performed after the value of the wheel speed or the like is detected in the preceding vehicle, and the detected value information is between the preceding vehicle and the own vehicle. This is the time until transmission to the vehicle by the communication system. In an inter-vehicle communication system, typically, information to be transmitted and received is digitized information. Therefore, _transmission / reception time τ _transmission of detected value information such as wheel speed is _transmitted in the inter-vehicle communication system. From the speed K [bit / sec] and the information amount A [bit] of the detected value such as the wheel speed (a signal amount for representing one wheel speed value),
τ _transmission = A / K (10)
Given by. The value of K can be obtained during transmission / reception, and the value of A is obtained when transmission / reception is completed.

The signal processing time τ _{signal processing} is a component (DC component, a component that does not contribute to pitch bounce vibration) other than disturbance included in information such as the wheel speed from the preceding vehicle as mentioned in the description related to FIG. That is, it is the sum of the time required for filtering to remove components not used for vibration suppression control from values such as wheel speed and the time required to calculate the wheel torque estimation / compensation component (in general, the HPF or LPF of the signal). Processing requires more processing time.) Since the signal processing time τ _{signal processing} is typically estimated from the signal processing amount, it may be determined in advance from the signal amount to be processed. Alternatively, it may be given by measuring the time from the completion of reception of a detected value such as one wheel speed from the preceding vehicle to the calculation of the wheel torque compensation component.

Further, as described above, the realization system response time τ _response is a response time required for adjusting the wheel torque after the drive device receives the control command. In the case of an engine, the response time is the engine speed. It can be determined by the generated torque. Therefore, a response time map using the engine speed and the generated torque as input parameters is prepared in advance, and the response time may be acquired from the map from the actual values of the engine speed and the generated torque.

In operation, when the preceding vehicle preview control is executed, the detected value such as the wheel speed of the preceding vehicle passes through the LPF / HPF 55 and then is input to the wheel torque estimator 52c as understood from the above. Further, the estimated wheel torque value is input to the feedback damping control unit 52b to calculate the wheel torque compensation component. When the output delay unit 54a receives the wheel torque compensation component, the output delay unit 54a calculates τ _movement from the distance L from the preceding vehicle before time τ _transmission + τ _{signal processing} and the vehicle speed Vs of the host vehicle, and the remaining time τ until the torque is realized. _remaining
τ _remaining = τ _movement− (τ _transmission + τ _{signal processing} ) (11)
Is calculated. The remaining time τ _remaining is a time value that decreases with time after calculation, and is compared with the realization system response time τ _response given from the instantaneous engine speed and the engine torque value,
Remaining time τ _remaining ≦ realization system response time τ _response (12)
When is established, the wheel torque compensation component is transmitted to the engine control command determination unit 53 via the (control gain multiplier 52d). Thus, the wheel torque compensation component is delayed and transmitted to the engine control command determination unit 53 in the control delay time given by the equation (9).

The specific configuration of the output delay unit 54a may be achieved by a program appropriately configured in the electronic control unit so as to realize the above operation. For example, since the wheel torque compensation component sequentially arrives at the output delay device, each value of the wheel torque compensation component is associated with the remaining time τ _remaining unique to the compensation component and temporarily stored in the memory. The remaining time τ _remaining stored in the memory is updated so as to be reduced every moment, and for each, it is determined whether or not the condition (12) is satisfied, and the value of the remaining time when the condition (12) is satisfied The wheel torque compensation component associated with may be transmitted. Further, as already described, since the control device of the present invention is a digital process, the process proceeds every predetermined control cycle time. Therefore, referring to the value obtained by dividing each of the above times by the control cycle time Tc, that is, the number of control cycles,
Remaining time τ _remaining / Tc <realization system response time τ _response / Tc + 1 (12a)
The wheel torque compensation component may be sent when the above is established. The reason why 1 is added to the right side is that both sides become integers.

  When the preceding vehicle preview control is not executed (when an instruction to stop the preview control is received from the preview determination unit), the feedback damping control using the wheel speed of the host vehicle is executed as described above. (Or, the vibration suppression control for disturbance is stopped). In that case, the output delay device transmits (passes through) the wheel torque compensation component without delay.

By the way, in the above example, τ _transmission , τ _{signal processing} , and τ _response time are given as examples to be considered in determining the control delay time, but those having a short length are not considered. (FIG. 5B shows the exaggerated length of each time for the sake of explanation). In the vibration control of the current general vehicle pitch / bounce vibration, the resonance frequency of the pitch / bounce vibration is about 1 to 2 Hz. In the case of this level of vibration, the conventional feedback vibration suppression control is executed. even if the delay of realization system response time τ _response is found to be too small to be a problem (control in time.). However, according to the control method of the preview control of the present invention, not only the realization system response time τ _response but also the processing time of frequency discrimination processing such as HPF can be “absorbed” by adjusting the control delay time. (The longer the processing time is, the shorter the control delay time is.) Therefore, it is advantageous in that a time for executing a more precise calculation of the wheel torque estimation / compensation component is given. In addition, when damping various body vibrations (drive system vibrations, engine shake vibrations, etc.) having a resonance frequency higher than the resonance frequency of the pitch bounce vibration, Although it may not be in time, according to the preview control according to the present invention, it is possible to control the braking / driving force or the wheel torque in time for the occurrence of a disturbance or the change of its vibration displacement by adjusting the control delay time. It should be understood that Furthermore, it should be understood that the time to be considered in determining the control delay time may be other than the above, and such a case also falls within the scope of the present invention.

(C) Control Gain Adjustment—Configuration and Operation of Control Gain Adjuster The wheel torque compensation component sent from the output delay unit 54a is added to the required drive torque by the adder a2 before being added to the control gain multiplier 52d. And the contribution is adjusted (although not shown, a similar control gain multiplier may be provided for the output of the feedforward damping control). In the control gain adjuster 52d, the compensation component U of the vibration suppression control is multiplied by the control gain λ,
λ · U (13)
Is sent to the adder a2. The value of the control gain λ is usually adjusted to limit the output so as not to send an unreasonable request to the drive device. However, in the present invention, when the preceding vehicle preview control is executed, in order to further adapt the wheel torque compensation component given using the wheel speed of the preceding vehicle to the vibration suppression control of the own vehicle, The control gain λ is calculated by the control gain adjuster 54c in the following manner, and the resultant control gain λ is used for the multiplication process in the control gain multiplier 52d of Expression (13).

Specifically, in the control gain adjuster 54c, the control gain λ is:
λ = λ _{vehicle speed difference} , λ _{wheel diameter} , λo (14)
Given by. Here, λo is a basic value, and is usually set to λo = 1, but may be set to λo <1 for any reason.

Among the factors of the control gain λ described above, the λ _{vehicle speed difference} is for correcting the magnitude of the disturbance effect caused by the difference in vehicle _{speed between} the preceding vehicle and the host vehicle. According to the research by the inventors of the present invention, when a certain vehicle is subjected to a certain disturbance, for example, when a certain vehicle passes over a protrusion on the road surface, the fluctuation of the wheel speed or the wheel torque caused thereby. The quantity was found to vary depending on the vehicle speed. Accordingly, when information about the wheel speed of the preceding vehicle is used to estimate the future wheel torque of the host vehicle and the vibration suppression control is executed based on the estimated wheel torque, the host vehicle is the same as the preceding vehicle. Even if it is affected by disturbances, if the vehicle speed of the preceding vehicle is different from that of the host vehicle, the amount of variation such as the wheel speed of the preceding vehicle is different from the amount of variation actually generated in the host vehicle. Deviations may occur in the magnitude of the torque compensation component. Therefore, in the present invention, the wheel torque compensation component calculated using the wheel speed or the like of the preceding vehicle is corrected based on the vehicle speed of the preceding vehicle and the vehicle speed of the host vehicle, and the calculated wheel torque compensation component is An attempt is made to make it suitable for vibration control of the own vehicle.

More specifically, the control gain λ _{vehicle speed difference} is
λ _{vehicle speed difference} = νv _{(own vehicle)} / νv _{(preceding vehicle)} (15)
May be given by Here, νv _{(own vehicle)} and νv _{(preceding vehicle)} are “control gain coefficients” determined as functions of the vehicle speed of the own vehicle and the preceding vehicle, respectively, and are given by the map of FIG. If necessary, the control gain coefficient νv in the map shown in the figure is the magnitude of the wheel torque compensation component generated when a certain disturbance is applied to the vehicle, and may be given experimentally or theoretically. During execution of the vibration suppression control, the control gain adjuster 54c determines the vehicle speed Vs of the own vehicle and the vehicle speed of the preceding vehicle at the time of occurrence of the wheel speed of the preceding vehicle that is the basis of the wheel torque compensation component to be transmitted. The vehicle speed, that is, the vehicle speed before time (τ _delay + τ _transmission + τ _{signal processing} ) is referred to, and control gain coefficients νv _{(own vehicle)} and νv _{(preceding vehicle)} corresponding to each vehicle speed are selected from the map. Then, the control gain λ _{vehicle speed difference} may be given by the above equation (15).

Among the factors of the above control gain λ, the λ _{wheel diameter} corrects the magnitude of the disturbance effect due to the difference in the wheel diameter between the preceding vehicle and the own vehicle (where the wheel diameter is the drive wheel diameter). Is to do. As in the case of the difference in vehicle speed, according to the research by the inventors of the present invention, when a certain vehicle is affected by a certain disturbance, for example, when a certain vehicle passes over a protrusion on the road surface, It has been found that the variation in wheel speed or wheel torque caused thereby varies depending on the wheel diameter. Therefore, when the vibration suppression control is executed using information such as the wheel speed of the preceding vehicle, if the wheel diameter of the preceding vehicle is different from that of the own vehicle, the amount of change such as the wheel speed of the preceding vehicle is Therefore, the magnitude of the wheel torque compensation component may vary. Therefore, in the present invention, the wheel torque compensation component calculated by using the wheel speed of the preceding vehicle or the like is roughly the same as the case where there is a difference in the vehicle speed between the preceding vehicle and the own vehicle. Correction is made based on the wheel diameter of the vehicle and the wheel diameter of the own vehicle, and an attempt is made to make the calculated wheel torque compensation component suitable for vibration control of the own vehicle.

More specifically, the control gain λ _{wheel diameter} is
λ _{wheel diameter} = νr _{(own vehicle)} / νr _{(preceding vehicle)} (16)
May be given by Here, νs _{(own vehicle)} and νs _{(preceding vehicle)} are control gain coefficients determined as functions of the wheel diameters of the own vehicle and the preceding vehicle, respectively, and are given by the map of FIG. If necessary, the control gain coefficient νs in the map of FIG. 6 is a magnitude of a wheel torque compensation component generated when a certain disturbance is applied to the vehicle, and may be given experimentally or theoretically. However, the wheel diameter is not a value that changes from moment to moment like the vehicle speed. Therefore, basically, at the stage when execution of the preceding vehicle preview control is instructed, the wheel diameter of the preceding vehicle is stored in the electronic control unit by inter-vehicle communication with the preceding vehicle. The control gain λ _{wheel diameter} may be determined by acquiring the values of the various specifications and determining the control gain coefficient νs from the map of FIG.

However, the wheel diameter of the vehicle may be changed by a tire change by the user, and the value after the change may not be reflected in the value of the specification in the electronic control unit of each vehicle. In preparation for such a case, in the apparatus of the present invention, the control gain adjuster 54c detects the wheel diameters of the preceding vehicle and the host vehicle while the vehicle is running, and the control gain λ is detected from the detected value. _{The wheel diameter} may be determined. FIG. 9B shows the determination process of the control gain λ _{wheel diameter} in the form of a flowchart. Referring to the figure, in the process of determining the control gain λ _{wheel diameter} , it is first determined whether or not there is a preceding vehicle (step 200). Here, it may be determined whether or not the preceding vehicle preview control is being executed. If there is a preceding vehicle, it is determined whether or not the difference in vehicle speed between the own vehicle and the preceding vehicle is smaller than a predetermined value ΔVs, that is, whether or not the vehicle speeds of the own vehicle and the preceding vehicle are substantially equal (step 220). ). Such conditions are referred to in order to eliminate errors due to deviations in vehicle speed in determining the wheel diameter and selecting the control gain coefficient (therefore, setting or changing the value of the control gain λ _{wheel diameter} is This is executed not only when the vehicle speed difference between the host vehicle and the preceding vehicle is smaller than the predetermined value ΔVs.

Thus, if it is determined that the vehicle speeds of the own vehicle and the preceding vehicle are substantially the same, the wheel speeds of each vehicle and the frequency analysis are executed (step 220). Here, as schematically shown in FIG. 9C, frequency analysis is performed by FFT of wheel speed, and a power spectrum of wheel speed is calculated. In the calculated spectrum, the frequency of the rotation primary component of the wheel speed is detected (usually, the rotation primary component appears as a peak in the spectrum and can be detected by any known peak detection method. .) Is executed. Since the primary rotation component is a fluctuation in the wheel speed that occurs every time the wheel rotates once, its frequency F corresponds to the rotation speed, and the wheel diameter r is
r [m] = Vs [km / hours] / (3.6 [k · hour / sec] × 2πF [Hz]) (17)
As given. Then, when the wheel diameter is calculated by the equation (17) for each of the own vehicle and the preceding vehicle, the control gain coefficient is determined using the map of FIG. 9A, and the equation (16) is determined. Thus, the control gain λ _{wheel diameter} is determined.

  Note that each factor of the control gain λ in the above equation (14) may be arbitrarily considered by the user or designer, except for λo, and all of the factors need not be reflected in the value of the control gain λ. Also good. In addition, a control gain factor for correcting the error of the compensation component by the preceding vehicle preview may be multiplied by a factor other than the vehicle speed difference or the wheel diameter difference. When the preview determination unit determines that preview is not possible, the calculation of Expression (14) may not be executed, and the control gain λ may be reduced. In particular, λ = 0 may be set. In this case, the vibration suppression control for the disturbance is completely stopped.

  Thus, according to the above description, when the preceding vehicle preview control is executed, the occurrence is predicted prior to the occurrence of the disturbance in the own vehicle, and the occurrence or vibration of the vibration due to the influence of the disturbance is matched to the generation time. The braking / driving force control or the wheel torque control can be executed so as to cancel or reduce the force.

  In the above embodiment, the preview determination unit is provided to determine whether or not the preceding vehicle preview control can be executed. Based on the determination, the vibration suppression control based on the preceding vehicle preview control and the normal feedback vibration suppression control are determined. It is to be understood that the vibration suppression control is continued even if there is no appropriate preceding vehicle. Furthermore, as another aspect, when it is determined that the vehicle does not follow the trajectory of the preceding vehicle and the vibration suppression control based on the appropriate preceding vehicle preview control cannot be executed (step 130 in FIG. 6A). Furthermore, a vehicle that can achieve appropriate preceding vehicle preview control may be searched from a vehicle that travels ahead of the preceding vehicle (first-to-first vehicle) or a vehicle that travels further ahead.

  Although the above description has been made in relation to the embodiment of the present invention, many modifications and changes can be easily made by those skilled in the art, and the present invention is limited to the embodiment exemplified above. It will be apparent that the invention is not limited and applies to various devices without departing from the inventive concept.

  For example, the vibration suppression control in the above embodiment is a vibration suppression control using the theory of an optimal regulator assuming a sprung or sprung / unsprung movement model as a motion model. As long as it uses wheel torque, it can also be applied to those that adopt a motion model other than those introduced here, or those that control vibration using a control method other than the optimal regulator. It belongs to the scope of the invention. The control philosophy of vibration suppression control based on the preceding vehicle preview of wheel torque disturbance according to the present invention is caused not only by pitch / bounce vibration, but also by fluctuations in wheel torque in the drive wheels such as drive system vibration and engine shake vibration. The present invention is also applicable to damping control of various vibrations appearing in the wheel torque, and such a case should be understood as belonging to the scope of the present invention. Further, the modification of the vibration suppression control may be performed by a method / algorithm other than that illustrated, and such a case should be understood to be within the scope of the present invention.

FIG. 1 shows a schematic diagram of an automobile in which a preferred embodiment of a vibration damping control device according to the present invention is realized. FIG. 2 shows the internal configuration of the electronic control unit of FIG. 1 in the form of a control block diagram. Each of the preceding vehicle information receiving unit, the radar, and the GPS device has a signal processing device in the electronic control device, and is configured to appropriately output information or signals necessary for the control of the present invention. Although not shown, necessary parameters in each control unit are input as appropriate. FIG. 3A is a diagram illustrating a state variable of vehicle body vibration that is suppressed in the operation of the vibration suppression control unit of the drive control device that is one of the preferred embodiments of the present invention. FIG. 3B is a diagram for explaining a “sprung vibration model” which is one of the mechanical motion models of the vehicle body vibration assumed in the vibration damping control unit of the preferred embodiment of the present invention. It is a figure explaining "a sprung and unsprung vibration model." FIG. 4 is a diagram showing the configuration of the vibration damping control unit in the preferred embodiment of the present invention in the form of a control block diagram. 4A and 4B are configurations of the feedforward vibration suppression control unit 52a and the feedback vibration suppression control unit 52b in FIG. 2, respectively. FIG. 5A is a schematic diagram showing the positional relationship between the host vehicle and the preceding vehicle when executing the preceding vehicle preview control in the present invention. The inter-vehicle distance is drawn smaller than the actual distance. FIG. 5B shows the passage of time until information such as the wheel speed of the preceding vehicle is transmitted to the host vehicle and a wheel torque compensation component based on the wheel speed is realized in the host vehicle. FIG. 6 shows, in the form of a flowchart, the control processing operation of the preview determination unit that determines whether or not the preceding vehicle preview control of the present invention can be executed. FIG. 7A is a block diagram showing a control configuration for detecting a shift in the wheel speed phase between the host vehicle and the preceding vehicle in the preview determination unit of FIG. The process of FIG. 7A may be executed independently of the control process of FIG. FIG. 7B schematically shows a change over time of the wheel speed processed in FIG. 7A. The wheel speed of each vehicle in the left figure is subjected to BPF processing to extract only its fluctuation component, and the amount of phase shift between the two is detected by passing the fluctuation component through the zero point. FIG. 8 is a graph showing a map for determining the control gain coefficient as a function of the vehicle speed used for determining the control gain in the form of a graph. FIG. 9A is a graph showing a map for determining the control gain coefficient as a function of the wheel diameter used for determining the control gain in the form of a graph. FIG. 9B shows a part of the control processing of the control gain adjuster for detecting the wheel diameter of the vehicle and determining the control gain while the vehicle is running in the form of a flowchart. FIG. 9C is a diagram illustrating a process of calculating the wheel diameter by performing frequency analysis on the wheel speed value in step 220 in FIG. 9B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vehicle body 12FL, FR, RL, RR ... Wheel 14 ... Accelerator pedal 20 ... Drive device 30FL, FR, RL, RR ... Wheel speed sensor 32 ... G sensor 50 ... Electronic control unit 70 ... Inter-vehicle communication system 72 ... GPS device 74: On-vehicle radar device or sonar device

Claims (12)

  A vibration suppression control device for a vehicle that suppresses vehicle body vibration of the vehicle by controlling a wheel torque generated at a contact point between a vehicle wheel and a road surface, the vehicle being controlled from a preceding vehicle traveling in front of the vehicle. An information receiving unit for receiving at least one of information representing wheel speed or wheel rotation speed, engine rotation speed, turbine rotation speed or transmission rotation speed value of a preceding vehicle; and a wheel of the vehicle using the information A wheel torque compensation component that compensates a wheel torque of the vehicle so as to suppress an amplitude of the vehicle body vibration based on the wheel torque estimation value is estimated and the wheel torque compensation component is used to estimate the torque estimated value and use the wheel torque compensation component to calculate the wheel A damping control unit that controls torque, and the damping control unit corrects the wheel torque compensation component based on the vehicle speed or wheel diameter of the vehicle and the vehicle speed or wheel diameter of the preceding vehicle. Apparatus characterized by comprising a correction unit.   2. The apparatus according to claim 1, wherein the vehicle body vibration is a pitch or bounce vibration of the vehicle body, a drive system vibration of the vehicle, or a shake vibration of the engine of the vehicle.   The apparatus according to claim 1, wherein the information receiving unit receives the information from the preceding vehicle through inter-vehicle communication between the vehicle and the preceding vehicle.   2. The apparatus according to claim 1, wherein the vibration suppression control unit receives the information when the vehicle reaches the position of the preceding vehicle when the information on the preceding vehicle used for calculating the wheel torque compensation component is generated. 3. The wheel torque control is executed so that the wheel torque compensation component calculated based on the wheel torque estimated value estimated by the step is reflected in the wheel.   The apparatus according to claim 1, wherein the compensation component correction unit determines a control gain for the wheel torque compensation component based on a vehicle speed of the vehicle and a vehicle speed of the preceding vehicle, and determines the wheel torque compensation component. The wheel torque is controlled by a value obtained by multiplying the control gain.   6. The apparatus of claim 5, wherein the compensation component correction unit includes a gain coefficient determination unit that determines a control gain coefficient of the wheel torque compensation component as a function of vehicle speed, and the control gain for the wheel torque compensation component is Determined based on the control gain coefficient determined by the gain coefficient determination unit corresponding to the vehicle speed of the vehicle and the control gain coefficient determined by the gain coefficient determination unit corresponding to the vehicle speed of the preceding vehicle. A device characterized by that.   7. The apparatus according to claim 6, wherein the control gain coefficient is determined based on a wheel torque compensation component that suppresses an amplitude of the vehicle body vibration given when the vehicle travels on a predetermined road surface at an arbitrary vehicle speed. A device characterized in that the value is a measured value.   The apparatus according to claim 1, wherein the compensation component correction unit determines a control gain for the wheel torque compensation component based on a wheel diameter of the vehicle and a wheel diameter of the preceding vehicle, and the wheel torque compensation. The wheel torque is controlled by a value obtained by multiplying a component by the control gain.   9. The apparatus of claim 8, wherein a wheel diameter of the vehicle is estimated from a wheel speed of the vehicle, and a wheel diameter of the preceding vehicle is estimated from a wheel speed of the preceding vehicle.   9. The apparatus according to claim 8, wherein a control gain for the wheel torque compensation component is determined when a difference between a vehicle speed of the vehicle and a vehicle speed of the preceding vehicle is substantially the same.   9. The apparatus of claim 8, wherein the compensation component correction unit includes a gain coefficient determination unit that determines a control gain coefficient of the wheel torque compensation component as a function of a wheel diameter, and the control gain for the wheel torque compensation component Is based on the control gain coefficient determined by the gain coefficient determination unit corresponding to the wheel diameter of the vehicle and the control gain coefficient determined by the gain coefficient determination unit corresponding to the wheel diameter of the preceding vehicle A device characterized by being determined.   12. The apparatus according to claim 11, wherein the control gain coefficient is based on a wheel torque compensation component that suppresses an amplitude of the vehicle body vibration that is given when the vehicle having an arbitrary wheel diameter travels on a predetermined road surface. A device characterized in that it is a determined value.

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