WO2010143238A1

WO2010143238A1 - Vehicle vibration control device and control method for same

Info

Publication number: WO2010143238A1
Application number: PCT/JP2009/002683
Authority: WO
Inventors: 水野浩
Original assignee: トヨタ自動車株式会社
Priority date: 2009-06-12
Filing date: 2009-06-12
Publication date: 2010-12-16
Also published as: JPWO2010143238A1

Abstract

Disclosed is a vehicle vibration control device that, by controlling the power generated by a vehicle-mounted power source, generates a vibration control torque that suppresses sprung vibration on the drive wheels to which this power is transmitted. The vibration control torque, which includes a parameter pertaining to the center of gravity of the vehicle, is generated as a result of the control of power in accordance with a dynamic motion model based on at least the sprung vibration of the vehicle. By correcting this parameter in accordance with a change in the center of gravity of the vehicle, the power is changed in such a way that the vibration control torque generated by the vehicle vibration control device is altered in accordance with the center of gravity of the vehicle. A sufficient vibration reduction effect is able to be produced thereby.

Description

Vehicle damping control device and control method for vehicle damping control device

The present invention relates to a vehicle damping control device and a control method for the vehicle damping control device.

2. Description of the Related Art Conventionally, as a vehicle vibration suppression control device that suppresses vehicle vibration, a vehicle vibration suppression control device that executes so-called sprung mass vibration suppression control that suppresses vehicle sprung vibration is known. Here, the sprung vibration of the vehicle is a frequency component (1 to 4 Hz) of the vibration generated in the vehicle body via the suspension by the input from the road surface to the vehicle wheel when the excitation source is the road surface (vehicle type or vehicle). The frequency components that appear prominently differ depending on the configuration of the vehicle, and many vehicles refer to vibrations with a frequency component in the vicinity of 1.5 Hz. The sprung vibrations of this vehicle include components in the vehicle pitch direction or bounce direction (vertical direction). It is included. The sprung mass damping referred to here is to suppress the sprung mass vibration of the vehicle.

In a conventional vehicle vibration damping control device, for example, as shown in Patent Document 1, a device that performs sprung mass damping by controlling a braking / driving force according to a required braking / driving force filtered by a damping filter. Proposed. This conventional vehicle vibration suppression control device corrects the filter characteristics based on the vehicle load weight, so that the actual vehicle sprung vibration characteristic and the vibration suppression control characteristic shift due to the increase or decrease of the vehicle load weight. The purpose is to suppress a reduction in vibration reduction effect due to control.

Further, as a conventional vehicle damping control device, for example, as shown in Patent Document 2, a device that performs sprung damping by wheel torque control based on power control of power generated by a power source mounted on a vehicle is proposed. Has been. This conventional vehicle damping control device performs sprung mass damping by means of wheel torque. When there is fluctuation in wheel torque, a dynamic motion model such as a sprung vibration model or a sprung / lower vibration model is used. Is used to predict the sprung vibration of the vehicle and control the power generated by the power source so as to generate the wheel torque that suppresses the predicted sprung vibration of the vehicle.

JP 2006-298293 A JP 2004-168148 A

By the way, in the vehicle vibration damping control device using the dynamic motion model, the wheel torque control is performed so as to predict the displacement in the pitch direction around the center of gravity of the vehicle or the displacement in the bounce direction at the center of gravity and suppress the displacement. This suppresses the sprung vibration. Here, the position of the center of gravity of the vehicle changes depending on the behavior of the vehicle, the number of passengers, the presence or absence of luggage, and the like. Therefore, in the dynamic motion model based on the center of gravity position set in advance according to the specifications of the vehicle, the accuracy of the center of gravity assumed in the mechanical motion model is different from the actual center of gravity position of the vehicle. There was a risk of lowering. In other words, the conventional vehicle vibration suppression control device may not be able to obtain a sufficient vibration reduction effect.

The present invention has been made in view of the above, and an object of the present invention is to provide a vehicle vibration suppression control device and a vehicle vibration suppression control device control method capable of sufficiently obtaining a vibration reduction effect.

In order to solve the above-described problems and achieve the object, the present invention controls the power generated by a power source mounted on a vehicle, thereby suppressing sprung vibration on a drive wheel that transmits the power. In the vehicle vibration suppression control device that generates vibration torque, the power is changed so that the vibration suppression torque is generated based on the position of the center of gravity of the vehicle.

In the vehicle vibration damping control device, the damping torque includes a parameter relating to a position of the center of gravity of the vehicle, and the power is controlled based on at least a mechanical motion model based on the sprung vibration of the vehicle. It is preferable that the parameter is corrected based on a change in the center of gravity position of the vehicle.

In the vehicle vibration control device, the center of gravity position of the vehicle is preferably estimated based on a detection value detected by a center-of-gravity position change detecting unit that detects a change in the center of gravity position of the vehicle.

In the vehicle vibration control device, it is preferable that the center-of-gravity position change detecting unit detects whether or not an occupant sitting on the vehicle is seated.

The present invention also provides a control of a vehicle damping control device that generates a damping torque that suppresses sprung vibration on a driving wheel that transmits the power by controlling the power generated by a power source mounted on the vehicle. In the method, the power for generating a vibration damping torque changed based on a position of the center of gravity of the vehicle is generated.

The vehicle vibration suppression control device and the vehicle vibration suppression control device control method according to the present invention have an effect that a vibration reduction effect can be sufficiently obtained by improving the accuracy of the mechanical motion model.

FIG. 1 is a diagram illustrating a schematic configuration example of a vehicle on which the vehicle vibration suppression control device according to the embodiment is mounted. FIG. 2 is a schematic diagram showing a functional configuration example of the vehicle vibration control unit in the form of a control block. FIG. 3 is a diagram for explaining the state variables of the vehicle body vibration that are suppressed in the vehicle vibration suppression control unit. FIG. 4 is a diagram illustrating an example of a dynamic motion model of vehicle body vibration assumed in the vehicle vibration suppression control unit. FIG. 5 is a diagram illustrating an example of a dynamic motion model of vehicle body vibration assumed in the vehicle vibration suppression control unit. FIG. 6 is a diagram illustrating a flowchart of the center-of-gravity position estimation method by the center-of-gravity position estimation unit.

Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same. In the following embodiment, a vehicle will be described in which only a gasoline engine is mounted as a power source for generating power, and an AT that is an automatic transmission is mounted as a transmission.

FIG. 1 is a diagram illustrating a schematic configuration example of a vehicle on which a vehicle vibration control device according to the embodiment is mounted. FIG. 2 is a schematic diagram showing a functional configuration example of the vehicle vibration control unit in the form of a control block. FIG. 3 is a diagram for explaining the state variables of the vehicle body vibration that are suppressed in the vehicle vibration suppression control unit. FIG. 4 is a diagram for explaining an example of a dynamic motion model of vehicle body vibration assumed in the vehicle vibration suppression control unit. FIG. 5 is a diagram illustrating an example of a dynamic motion model of vehicle body vibration assumed in the vehicle vibration suppression control unit. FIG. 6 is a diagram illustrating a flowchart of the center-of-gravity position estimation method by the center-of-gravity position estimation unit.

The vehicle vibration suppression control device 1 according to the present embodiment is applied to a vehicle 10 equipped with a gasoline engine 21 (hereinafter simply referred to as “engine”) as a power source, as shown in FIG. In the vehicle 10 to which the vehicle vibration suppression control device 1 according to the present embodiment is applied, the engine 21 is mounted on the front portion in the forward traveling direction of the vehicle 10 and the driving wheels are the left and right rear wheels 30RL, 30RR. The rear wheel drive. In addition, the mounting position of the engine 21 of the vehicle 10 is not limited to only the front portion, and may be mounted on either the rear portion or the central portion. Further, the drive format of the vehicle 10 is not limited to only the rear wheel drive, and may be any format of front wheel drive and four wheel drive.

The vehicle 10 to which the vehicle vibration damping control device 1 is applied has wheels 30FL and 30FR which are left and right front wheels and wheels 30RL and 30RR which are left and right rear wheels, as shown in FIG. Further, the vehicle 10 detects an accelerator pedal 60 operated by the driver and a request value by the driver's accelerator operation, that is, an accelerator pedal depression amount θa that is a depression amount of the accelerator pedal 60, and corresponds to the accelerator pedal depression amount θa. It has an accelerator pedal sensor 70 that outputs an electrical signal to an ECU (Electric Control Unit) 50. The vehicle 10 is mounted with a driving device 20 that applies driving force to the wheels 30RL and 30RR in accordance with the driver's accelerator operation in various known modes. In the illustrated example, the drive device 20 is configured such that power (drive torque) generated by the engine 21 is transmitted to the wheels 30RL and 30RR via the AT 22, the differential gear device 23, and the like. Although not shown here, the vehicle 10 is provided with a braking device for generating 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 various known vehicles. It is done.

The operation of the drive device 20 is controlled by an ECU 50 that is also used as the vehicle vibration damping control device 1. The ECU 50 may include various known types of microcomputers and drive circuits having a CPU, ROM, RAM and input / output port devices interconnected by a bidirectional common bus. The ECU 50 receives a signal representing a wheel speed Vwi (i = FL, FR, RL, RR) from a wheel speed sensor 40i (i = FL, FR, RL, RR) mounted on the wheels 30FL, 30FR, 30RL, 30RR. Then, signals of the engine rotation speed (output rotation speed of the engine 21) Er and the accelerator pedal depression amount θa from the sensors provided in each part of the vehicle 10 are input. In addition to the above, the ECU 50 detects various detection signals for obtaining various parameters necessary for various controls to be executed in the vehicle 10 of the present embodiment, for example, parameters corresponding to the operating environment of the engine 21 (cooling water). Temperature, intake air temperature, intake air pressure, atmospheric pressure, oil temperature, etc.).

As shown in FIG. 2, for example, the ECU 50 controls the operation of the engine 21, in particular, the power generated by the engine 21 based on a controlled variable, in this embodiment, a drive control device that also functions as a drive control device that controls the required torque Te. The vibration control device 1 includes a vibration control device 2 that controls the operation of a brake device (not shown). In the present embodiment, the driving force control device is described as being configured to be shared by the vehicle vibration suppression control device 1, but the present invention is not limited to this, and the driving force control device and the ECU 50 are configured separately. The driving force control device may be connected to the ECU 50. Similarly, the brake control device 2 may be individually configured, and the brake control device 2 may be connected to the ECU 50.

As shown in FIG. 1, the braking control device 2 generates a pulse-type electrical signal that is sequentially generated each time the wheels 30FL, 30FR, 30RL, and 30RR rotate by a predetermined amount, and the wheel speed sensors 40FL, 40FR, and 40RL. 40RR, each wheel rotation speed ωi (i = FL, FR, RL, RR) is calculated by measuring the time interval at which this sequentially input pulse signal arrives, and the wheel radius r Each wheel speed Vwi is calculated by multiplying. In the present embodiment, the braking control device 2 determines the average value r · ω of the wheel speeds VwFL, VwFR, VwRL, and VwRR corresponding to the wheels 30FL, 30FR, 30RL, and 30RR, respectively. Then, it outputs to the vehicle vibration suppression control part 4). The calculation from the wheel rotation speed to the wheel speed may be performed by the vehicle vibration suppression control device 1. In that case, the wheel rotation speed is output from the braking control device 2 to the vehicle vibration suppression control device 1).

The braking control device 2 also performs various types of known ABS control, automatic braking control such as VSC (Vehicle Stability Control), TRC (Traction Control), that is, frictional force between the wheels 30FL, 30FR, 30RL, 30RR and the road surface. (The vector sum of the longitudinal force and lateral force of the wheels 30FL, 30FR, 30RL, and 30RR) is excessively suppressed and exceeds the limit, or the frictional force of the wheels 30FL, 30FR, 30RL, and 30RR exceeds the limit. It is possible to control the longitudinal force or slip rate on the wheels to suppress the deterioration of the behavior of the vehicle 10 due to exceeding, or the wheels 30FL, 30FR, 30RL, 30RR of ABS control, VSC, TRC. VDIM (Ve) which stabilizes the behavior of the vehicle 10 including steering control in addition to slip ratio control hicle Dynamics Integrated Management). In addition, when VDIM is mounted, the braking control apparatus 2 will comprise a part of VDIM. Here, the braking control device 2 performs a control by changing the behavior of the vehicle 10 in the automatic braking control (ABS control, VSC, TRC, VDIM), that is, a stable behavior is obtained by changing the behavior of the vehicle 10. In order to positively control the power, the power generated by the engine 21 may be controlled. In the present embodiment, the braking control device 2 changes the required torque Te when performing driving force control to change and control the behavior of the vehicle 10 based on automatic braking control. That is, the braking control device 2 also has a function as a vehicle behavior control unit. When the required torque Te is changed based on the automatic braking control, the braking control device 2 determines the braking torque correction amount that can change the driving torque of the engine 21 so that the behavior of the vehicle 10 becomes a stable behavior. Output to the vibration control device 1. Here, the braking torque correction amount output from the braking control device 2 to the vehicle damping control device 1 is added to or subtracted from the required torque Te calculated by the required torque calculation unit 3a. As a result, the required torque Te is changed so as to change and control the behavior of the vehicle 10 based on the damping torque correction amount, and a control command corresponding to the changed required torque Te is sent from the control command determination unit 3c to the engine. 21 will be output. Note that the braking control device 2 may calculate the accelerator pedal depression amount when controlling the engine torque in order to change and control the behavior of the vehicle 10 based on the automatic braking control. In this case, the calculated accelerator pedal depression amount is output to the required torque calculation unit 3a of the vehicle vibration suppression control device 1.

As shown in FIG. 2, the vehicle vibration suppression control device 1 is a drive control device in which a drive request from the driver is a required torque that is a drive torque of the engine 21 requested by the driver based on the accelerator pedal depression amount θa. Determined as Te. Here, in the vehicle vibration suppression control device 1, control for suppressing vibration in the pitch direction and bounce direction of the vehicle 10 by controlling the driving torque of the engine 21, that is, control for suppressing sprung vibration. In order to execute the control, the required torque Te is corrected, and a control command corresponding to the corrected required torque Te is given to the engine 21. The vehicle vibration damping control device 1 includes a drive control unit 3 and a vehicle vibration damping control unit 4.

The drive control unit 3 includes a required torque calculation unit 3a, an adder 3b, and a control command determination unit 3c. The required torque calculation unit 3a calculates the required torque Te based on the accelerator depression amount θa by a known arbitrary method. The adder 3b corrects the required torque Te calculated by the required torque calculation unit 3a with the damping torque correction amount calculated by the vehicle braking control unit 4, that is, the required torque Te calculated by the required torque calculation unit 3a. Is corrected based on the damping torque. The control command determination unit 3c generates a control command for the engine 21 based on the required torque Te corrected by the damping torque correction amount, and outputs the generated control command to each controller (not shown) of the engine 21.

The vehicle vibration damping control unit 4 executes so-called sprung mass damping control that suppresses sprung vibration of the vehicle 10. Here, the sprung vibration of the vehicle 10 refers to an input from the road surface to the wheels 30FL and 30FR that are the left and right front wheels of the vehicle 10 and the wheels 30RL and 30RR that are the left and right rear wheels according to the unevenness of the road surface via the suspension. The vibration generated in the vehicle body of the vehicle 10 is a vibration having a frequency component of 1 to 4 Hz, more specifically 1.5 Hz, and the sprung vibration of the vehicle 10 includes the pitch direction or the bounce direction (vertical direction) of the vehicle 10. ) Ingredients are included. The sprung mass damping referred to here is to suppress the sprung mass vibration of the vehicle 10. The vehicle vibration suppression control unit 4 receives a frequency component of 1 to 4 Hz (notably depending on the type of vehicle and the configuration of the vehicle) by inputting from the road surface to the wheels 30FL and 30FR that are the left and right front wheels of the vehicle 10 and the wheels 30RL and 30RR that are the left and right rear wheels. The frequency components appearing in the motor are different, and in many vehicles, when the vibration in the pitch direction or the bounce direction (vertical direction) of the vehicle 10 occurs, the engine 21 generates power in the opposite phase. Then, the "wheel torque" (torque acting between the wheel and the grounding road surface) acting on the road surface by the wheel (drive wheel during driving) is adjusted to suppress the vibration. In other words, the vehicle damping control unit 4 controls the power of the engine 21, that is, the driving torque, thereby generating the damping torque that suppresses the sprung vibration on the driving wheels 30RL and 30RR that transmit the driving torque. Torque control is performed to suppress the vibration. As a result, the vehicle vibration suppression control unit 4 of the vehicle 10 improves the driver's steering stability, the ride comfort of the occupant, and the like. Further, according to the control of the power generated by the engine 21, that is, the vibration suppression control by the power control, the vibration is suppressed rather than suppressed by absorbing the vibration energy generated as in the vibration suppression control by the suspension. Since the generation of vibration energy is suppressed by adjusting the source of the generated force, there is an advantage that the damping action is relatively quick and the energy efficiency is good. Further, in the vibration suppression control by power control, since the control target is concentrated on the power (drive torque) of the power source, the control adjustment is relatively easy.

In the vehicle damping control unit 4, (1) acquisition of wheel torque of a wheel by a force acting between the road surface and a wheel, (2) acquisition of a pitch / bounce vibration state quantity, and (3) pitch / bounce vibration state. The calculation of the correction amount of the wheel torque that suppresses the amount and the change of the required torque Te based on this are executed. In the present embodiment, the wheel torque (1) is calculated based on the wheel speed (or the wheel rotation speed of the wheel) of the wheel received from the braking control device 2, but the present invention is not limited to this. As the wheel torque, a wheel torque estimated value may be calculated based on the engine rotation speed, or a sensor that can directly detect the value of the wheel torque while the vehicle 10 is traveling, for example, a wheel torque sensor or a wheel halve. It may be a detected value of wheel torque actually generated in the wheel by a force meter or the like. The vehicle damping control unit 4 is realized in the processing operations (1) to (3).

In the vehicle 10, for example, when a change in wheel torque occurs based on the driver's accelerator operation, that is, the driver's drive request, in the vehicle body of the vehicle 10 illustrated in FIG. 3, the vertical direction of the center of gravity Cg of the vehicle body ( Z-direction bounce vibration (bounce direction vibration) and pitch direction (θ direction) pitch vibration (pitch direction vibration) around the center of gravity of the vehicle body may occur. Further, when an external force or torque (disturbance) is applied by the input from the road surface to the wheels 30FL, 30FR, 30RL, 30RR of the vehicle 10 according to the unevenness of the road surface while the vehicle 10 is traveling, the disturbance is transmitted to the vehicle 10, Again, pitch / bounce vibration can occur in the car body. Therefore, the vehicle vibration suppression control unit 4 constructs a dynamic motion model of the pitch / bounce vibration of the vehicle body of the vehicle 10, and in the model, the requested torque Te (which is a control amount corresponding to the driving request of the driver is changed to the wheel torque. ) And the current wheel torque (estimated value) are input to the vehicle body displacements z and θ and the rate of change dz / dt and dθ / dt, that is, the state variables of the vehicle body vibration are calculated. Then, the power control of the engine 21 is performed so that the state variable obtained from the model converges to 0, that is, the pitch / bounce vibration can be suppressed (that is, a request that is a control amount corresponding to the driving request of the driver). The torque Te will be changed.)

As shown in FIG. 2, the vehicle vibration suppression control unit 4 includes a feedforward control unit 4a, a feedback control unit 4b, a gravity center position estimation unit 4c, and a drive torque conversion unit 4d.

The feedforward control unit 4a has a so-called optimum regulator configuration, and here includes a wheel torque conversion unit 4e, a motion model unit 4f, and an FF secondary regulator unit 4g. In the feedforward control unit 4a, a value (driver requested wheel torque Two) obtained by converting the required torque Te into the wheel torque by the wheel torque conversion unit 4e is input to the motion model unit 4f of the pitch / bounce vibration of the vehicle body of the vehicle 10. . In the motion model unit 4f, the response of the state variable of the vehicle 10 to the input torque is calculated, and the driver request wheel that converges the state variable to the minimum based on a predetermined gain K described later in the FF secondary regulator unit 4g. As the correction amount of the torque Two, the FF vibration damping torque correction amount U · FF is calculated. This FF system damping torque correction amount U · FF is the FF control amount of the required torque Te in the feedforward control unit 4a based on the required torque Te for the engine 21.

The feedback control unit 4b has a so-called optimal regulator configuration, and includes a wheel torque estimation unit 4h, a motion model unit 4f also used as a feedforward control unit 4a, and an FB secondary regulator unit 4i. Consists of. As will be described later in the wheel torque estimation unit 4h, the feedback control unit 4b calculates a wheel torque estimated value Tw based on the average value r · ω of the wheel speed, and this wheel torque estimated value Tw Input to the model unit 4f. Here, since the motion model unit of the feedforward control unit 4a and the motion model unit of the feedback control unit 4b are the same, they are also used by the motion model unit 4f, but may be provided separately. In the motion model unit 4f, the response of the state variable of the vehicle 10 to the input torque is calculated, and the driver request wheel that converges the state variable to the minimum based on a predetermined gain K described later in the FB secondary regulator unit 4i. As the correction amount of the torque Two, the FB vibration damping torque correction amount U · FB is calculated. The feedback control unit according to the fluctuation of the wheel speed based on the external force or torque (disturbance) caused by the input from the road surface to the wheels 30FL, 30FR, 30RL, 30RR of the vehicle 10 from the road surface. This is the FB control amount of the required torque Te in 4b.

In the vehicle damping control unit 4, the FF system damping torque correction amount U · FF, which is the FF control amount of the feedforward control unit 4a, and the FB type damping torque correction amount U · FB, which is the FB control amount of the feedback control unit 4b. Are added to the adder 4k, and the adder 4k adds the FF vibration damping torque correction amount U · FF and the FB vibration damping torque correction amount U · FB to calculate the vibration damping torque, thereby converting the drive torque. The part 4d converts the damping torque into a damping torque correction amount that is a value obtained by converting the damping torque into a unit of driving torque, and the converted damping torque correction amount is output to the adder 3b. That is, the vehicle vibration suppression control unit 4 corrects the required torque Te, which is a control amount, based on the vibration suppression torque acquired based on the mechanical motion model, and reduces the vibration suppression torque that suppresses the sprung vibration of the vehicle 10. Change to a value that can occur.

Accordingly, the vehicle vibration suppression control unit 4 changes the driving torque generated by the engine 21 to generate the wheel torque that reduces the fluctuation of the wheel speed that causes the vehicle 10 to generate the vibration of 1 to 4 Hz by the fluctuation of the driving torque. Can be performed.

Here, in the sprung mass damping control in the vehicle damping control unit 4, as described above, the driver requested wheel torque Two, the wheel are assumed assuming the dynamic motion model in the pitch direction and the bounce direction of the vehicle body of the vehicle 10. A state equation of a state variable in the pitch direction or bounce direction is configured with the estimated torque value Tw (disturbance) as input. From such a state equation, the input (vibration torque) for converging the state variables in the pitch direction and the bounce direction to zero is determined using the theory of the optimal regulator, and the required torque Te is determined based on the obtained vibration damping torque. It is corrected.

As a dynamic motion model in the bounce direction or pitch direction of the vehicle body of the vehicle 10, for example, as shown in FIG. 4, the vehicle body is regarded as a rigid body S having a mass M and an inertia moment I, and this rigid body S has an elastic modulus kf and damping. It is assumed that the vehicle is supported by a front wheel suspension of a rate cf, a rear wheel suspension of an elastic modulus kr, and a damping rate cr (a vehicle body sprung vibration model). In this case, the motion equation in the bounce direction (the mechanical motion model in the bounce direction) and the motion equation in the pitch direction (the mechanical motion model in the pitch direction) of the center of gravity Cg of the vehicle body are expressed as the following formula 1. be able to.

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

The above equations (1a) and (1b) are shown in the following equation (2a), with the displacements z and θ of the vehicle body of the vehicle 10 and their change rates dz / dt and dθ / dt as the state variable vector X (t). Can be rewritten in the form of a state equation (of a linear system).

dX (t) / dt = A · X (t) + B · u (t) (2a)

In the above formula (2a), X (t), A, and B are respectively

The elements a1 to a4 and b1 to b4 of the matrix A are given by putting together the coefficients of z, θ, dz / dt, dθ / dt in the above 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 above state equation (2a). Therefore, from the above equation (1b), the element p1 of the matrix B is
p1 = h / (I · r)
It is.

In the above state equation (2a),

u (t) = − K · X (t) (2b)

Then, the equation of state (2a) is

dX (t) / dt = (A−BK) · X (t) (2c)

It becomes. Therefore, 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). ), A 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 If K is determined, the damping torque u (t) that suppresses the bounce / pitch vibration is determined.

The gain K can be determined using a so-called optimal regulator theory. According to this theory, a quadratic evaluation function (integral range is 0 to ∞)

J = ∫ (X ^T QX + u ^T Ru) dt (3a)

When the value of is minimized, 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 Here, P is, Rikatti 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.

Note that Q and R in the evaluation function J and the Riccati equation are respectively a semi-positive definite symmetric matrix and a positive definite symmetric matrix, and are weight matrices of the evaluation function J determined by the system designer. For example, in the case of the motion model here, Q and R are

In Equation (3a), the norm (magnitude) of a particular one of the state vector components, for example, dz / dt, dθ / dt, is the other component, for example, the norm of z, θ. When the value is set larger, 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. Here, the gain K corresponding to the feedforward control unit 4a may be different from the gain K corresponding to the feedback control unit 4b. For example, the gain K corresponding to the feedforward control unit 4a may be a gain corresponding to the driver's feeling of acceleration, and the gain K corresponding to the feedback control unit 4b may be a gain corresponding to the driver's response and responsiveness.

In the actual sprung mass damping control in the vehicle damping control unit 4, as shown in the block diagram of FIG. 2, the motion model unit 4f uses the torque input value to calculate the differential equation of the equation (2a). By solving, the state variable vector X (t) is calculated. Next, the gain K determined to converge the state variable vector X (t) to 0 or the minimum value as described above by the FF secondary regulator unit 4g and the FB secondary regulator unit 4i is output from the motion model unit 4f. The value u (t) obtained by multiplying the state vector X (t), that is, the FF system damping torque correction amount U · FF and the FB system damping torque correction amount U · FB is the engine 21 in the drive torque converter 4d. The required torque Te is corrected by the adder 3b. The system represented by the equations (1a) and (1b) is a resonant system, and the value of the state variable vector for an arbitrary input is substantially only the natural frequency component of the system. Therefore, by configuring so that the required torque Te is corrected by u (t) (converted value thereof), a component of the natural frequency of the system, that is, pitch / bounce in the vehicle body of the vehicle 10 among the required torque Te. The component causing the vibration is corrected, and the pitch / bounce vibration in the vehicle body of the vehicle 10 is suppressed. When the component of the natural frequency of the system disappears in the required torque Te according to the driving request of the driver, the component of the natural frequency of the system in the control command according to the required torque Te output to the engine 21 is -U (t) only, and vibration due to Tw (disturbance) converges.

The parameters of the mechanical motion model used in the motion model unit 4f are stored in the vehicle vibration control device 1. The vehicle damping control device 1 stores parameters such as M, I, Lf, Lr, h, r, kf, cf, kr, cr, and the like, and the FF system damping torque correction amounts U / FF and FB This is used when calculating the system damping torque correction amount U · FB. In addition, the vehicle vibration suppression control device 1 stores in advance reference specifications that are specifications of the vehicle 10 based on a state in which no occupant is in the vehicle and no load is loaded. Includes Lfb, the distance from the center of gravity Cgb to the front wheel axis, Lrb, the distance from the center of gravity Cgb to the rear wheel axis, hb, the distance from the road surface to the center of gravity Cgb, and Mb, the mass at the center of gravity Cgb. Here, initial values of the parameters M, Lf, Lr, and h are Lfb, Lrb, hb, and Mb, respectively.

As a dynamic motion model in the bounce direction or pitch direction of the vehicle body of the vehicle 10, for example, as shown in FIG. 5, a model that takes into account the spring elasticity of the tires of the front wheels and the rear wheels in addition to the configuration of FIG. 4. (A sprung / lower vibration model of the vehicle body of the vehicle 10) may be employed. Assuming that the tires of the front wheels and the rear wheels have the elastic moduli ktf and ktr, respectively, as understood from FIG. 5, the motion equation in the bounce direction and the motion equation in the pitch direction of the center of gravity Cg of the vehicle body are , Which can be expressed as the following mathematical formula 4.

In the above equation 4, 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)-(4d) constitute a state equation like Equation (2a) as in FIG. 4 using z, θ, xf, xr and their time differential values as state variable vectors (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 size of the state variable vector to 0 can be determined. The actual vibration suppression control in the vehicle vibration suppression control unit 4 is the same as in the case of FIG.

Here, in the feedback control unit 4b of the vehicle vibration suppression control unit 4 of FIG. 2, for example, the wheel torque input as a disturbance is actually detected by providing a torque sensor on each wheel 30FL, 30FR, 30RL, 30RR. Although it may be configured, the wheel torque estimated value Tw estimated by the wheel torque estimating unit 4h from other detectable values in the traveling vehicle 10 is used here.

The estimated wheel torque value Tw is estimated by the following equation (5) using, for example, the average value ω of the wheel rotation speed obtained from the wheel speed sensor corresponding to each wheel or the time derivative of the average value r · ω of the wheel speed. Can be calculated.

Tw = M · r ² · dω / dt (5)

In the above formula (5), M is the mass of the vehicle, and r is the wheel radius. That is, assuming that the sum of the driving forces generated at the ground contact points of the driving wheels is equal to the overall driving force M · G (G is acceleration) of the vehicle 10, the estimated wheel torque value Tw is given by (5a).

Tw = M · G · r (5a)

The acceleration G of the vehicle is given by the following equation (5b) from the differential value of the wheel speed r · ω.

G = r · dω / dt (5b)

Therefore, the wheel torque is estimated as in the above equation (5).

By the way, the vehicle vibration suppression control unit 4 of the present embodiment is an FF system control that is an FF control amount of the required torque Te in the feedforward control unit 4a based on the required torque Te that is a control amount according to the driving request of the driver. Vehicle damping that sets damping torque on the basis of the amount of vibration torque correction and the amount of FB system damping torque correction that is the FB control amount of the required torque Te in the feedback control unit 4b based on the wheel speed of the wheel of the vehicle 10 The control unit 4 corrects the FF system damping torque correction amount or the FB system damping torque correction amount based on the driving state of the vehicle 10 to achieve appropriate damping control according to the driving state of the vehicle 10. ing.

Here, as described above, the vehicle vibration suppression control unit 4 is basically an independent separate control system, although the feedforward control unit 4a and the feedback control unit 4b also serve as the motion model unit 4f. After calculating the FF system damping torque correction amount and the FB system damping torque correction amount, respectively, the FF system damping torque correction amount and the FB system damping torque correction amount are added to obtain the damping torque. It is set. For this reason, the vehicle vibration suppression control unit 4 performs the FF system damping torque correction amount of the feedforward control unit 4a and the FB system damping torque correction amount of the feedback control unit 4b before the actual damping torque is set. Thus, it is possible to individually perform upper and lower limit guards and to perform corrections. In addition, this makes it easy to block either one of the controls depending on the situation of the vehicle 10.

The vehicle vibration suppression control unit 4 of this embodiment includes an FF control correction unit 4l and an FF control gain setting unit 4m in the feedforward control unit 4a, and an FB control correction unit 4n and an FB control gain in the feedback control unit 4b. And a setting unit 4o. The vehicle damping control unit 4 corrects the FF system damping torque correction amount by the FF control correcting unit 4l and the FF control gain setting unit 4m, while the FB control correcting unit 4n and the FB control gain setting unit 4o The damping torque correction amount is corrected. That is, the vehicle damping control unit 4 sets the FF control gain according to the state of the vehicle 10 with respect to the FF system damping torque correction amount, and multiplies the FF system damping torque correction amount by the FF control gain. By correcting the system damping torque correction amount, setting the FB control gain according to the state of the vehicle 10 with respect to the FB system damping torque correction amount, and multiplying the FB system damping torque correction amount by this FB control gain, the FB Correct the system damping torque correction amount.

The FF control correction unit 4l is positioned after the FF secondary regulator unit 4g and before the adder 4k, and the FF system damping torque correction amount U / FF is input from the FF secondary regulator unit 4g to correct the FF system control. The vibration torque correction amount U · FF is output to the adder 4k. The FF control correction unit 4l multiplies the FF system damping torque correction amount U · FF by the FF control gain K · FF set by the FF control gain setting unit 4m, thereby FF system damping torque correction amount U · FF. -Correct FF based on FF control gain K-FF. The FF control gain setting unit 4m sets the FF control gain K · FF according to the state of the vehicle 10. In other words, the FF system damping torque correction amount U / FF input from the FF secondary regulator unit 4g to the FF control correction unit 4l is changed according to the state of the vehicle 10 by the FF control gain setting unit 4m. Thus, the FF control correction unit 4l corrects it according to the state of the vehicle 10.

The FF control correction unit 4l may perform upper and lower limit guards so that the FF system damping torque correction amount U · FF is within a preset upper and lower limit guard value range. The FF control correction unit 4l is, for example, an allowable engine torque fluctuation as an allowable driving force fluctuation value of the engine 21 set in advance for the FF system damping torque correction amount U · FF input from the FF secondary regulator unit 4g. The upper / lower limit guard value is set to a value corresponding to the upper / lower limit guard value (for example, a value converted to the unit of the drive torque of the engine 21 from the range of tens of Nm to 0 Nm), and the FF system damping torque correction amount U · FF may be corrected. As a result, the FF control correction unit 41 can set an appropriate FF system damping torque correction amount U / FF taking into account other controls than the sprung mass damping control by the vehicle damping control unit 4, for example. That is, interference between the sprung mass damping control by the vehicle damping control unit 4 and other controls can be suppressed. Further, the FF control correction unit 4l sets, for example, a value corresponding to an allowable acceleration / deceleration of the vehicle 10 set in advance to the FF system damping torque correction amount U · FF before being output to the adder 4k as an upper limit guard. Upper limit guarding may be performed as a value (for example, a range that is less than +0.00 G when acceleration / deceleration is converted), and the FF vibration damping torque correction amount U / FF may be corrected. Thereby, the FF control correction unit 4l is driven by a change in motion of the vehicle 10 by sprung mass damping control by the vehicle vibration damping control unit 4 for improving the driving stability of the driver, the ride comfort of the occupant, and the like. It is possible to set an appropriate FF system damping torque correction amount U · FF that can prevent the driver from unexpectedly increasing and prevent the driver from feeling uncomfortable.

The FB control correction unit 4n is positioned after the FB secondary regulator unit 4i and before the adder 4k, and receives the FB system damping torque correction amounts U and FB from the FB secondary regulator unit 4i. The vibration torque correction amount U · FB is output to the adder 4k. The FB control correction unit 4n multiplies the FB system damping torque correction amount U · FB by the FB control gain K · FB set by the FB control gain setting unit 4o, thereby obtaining the FB system damping torque correction amount U · FB. -Correct FB based on FB control gain K / FB. The FB control gain setting unit 4o sets the FB control gain K · FB according to the driving state of the vehicle 10. That is, the FB system damping torque correction amount U / FB input from the FB secondary regulator unit 4i to the FB control correction unit 4n is set to the driving state of the vehicle 10 by the FB control gain setting unit 4o. By setting accordingly, the FB control correction unit 4n will correct the vehicle 10 according to the driving state.

The FB control correction unit 4n may perform upper and lower limit guards so that the FB system damping torque correction amount U · FB is within a preset upper and lower limit guard value range. The FB control correction unit 4n is, for example, an allowable engine torque fluctuation as an allowable driving force fluctuation value of the engine 21 set in advance for the FB system damping torque correction amount U · FB input from the FB secondary regulator unit 4i. The upper / lower limit guard is performed with the value corresponding to the value as the upper / lower limit guard value (for example, a range of ± several tens of Nm in terms of the drive torque unit of the engine 21), and the FB system damping torque correction amount U · FB is set to It may be corrected. As a result, the FB control correction unit 4n can set an appropriate FB system damping torque correction amount U / FB taking into account other controls than the sprung mass damping control by the vehicle damping control unit 4, for example. That is, interference between the sprung mass damping control by the vehicle damping control unit 4 and other controls can be suppressed. Further, the FB control correction unit 4n sets, for example, values corresponding to the allowable acceleration / deceleration of the vehicle 10 set in advance to the FB system damping torque correction amount U · FB before being output to the adder 4k. Upper and lower limit guards may be performed as a guard value (for example, a range that is within ± a / 100 G when acceleration / deceleration is converted) to correct the FB system damping torque correction amount U · FB. As a result, the FB control correction unit 4n is driven by a change in motion of the vehicle 10 by sprung mass damping control by the vehicle vibration damping control unit 4 for improving the driving stability of the driver, the ride comfort of the occupant, and the like. It is possible to set an appropriate FB system damping torque correction amount U · FB that can prevent the driver from unexpectedly increasing and prevent the driver from feeling uncomfortable.

The vehicle vibration suppression control unit 4 of the present embodiment uses the vehicle speed of the vehicle 10 as a parameter representing the state of the vehicle 10, the gear stage if the AT 22 mounted on the vehicle 10 has a plurality of gear stages, and the engine 21. Based on the engine rotation speed and the required torque Te as the output rotation speed, the FF control correction unit 4l and the FB control correction unit 4n may correct the FF system damping torque correction amount and the FB system damping torque correction amount. Further, the vehicle damping control unit 4 may correct the FB system damping torque correction amount based on the driving state of the AT 22 mounted on the vehicle 10 by the FB control correcting unit 4n. Further, when the power source is a diesel engine, the vehicle damping control unit 4 may correct the FB system damping torque correction amount based on the allowable target fuel injection amount of the diesel engine by the FB control correction unit 4n. That is, the FF control gain setting unit 4m and the FB control gain setting unit 4o may set the FF control gain K · FF and the FB control gain K · FB based on these.

The center-of-gravity position estimation unit 4 c estimates the center-of-gravity position of the actual vehicle 10. The center-of-gravity position estimation unit 4 c estimates the actual center-of-gravity position of the vehicle 10 based on the detection value detected by the center-of-gravity position change detection unit that detects a change in the center-of-gravity position of the vehicle 10. In the embodiment, the center-of-gravity position estimation unit 4c is a parameter (hereinafter, referred to as a parameter relating to the center-of-gravity position of the vehicle 10 in the mechanical motion model) based on the load Fi (i ≧ 1) detected by the load sensor 80i (i ≧ 1). The center of gravity position of the actual vehicle 10 is estimated by correcting the “center of gravity parameter”. That is, the center-of-gravity position estimation unit 4c corrects the center-of-gravity parameter based on the change in the center-of-gravity position of the vehicle. Here, the center-of-gravity parameter refers to a parameter related to the position of the center of gravity Cg in the longitudinal direction of the vehicle 10, a parameter related to the position of the center of gravity Cg in the vertical direction of the vehicle 10, and preferably includes a parameter related to the mass of the vehicle 10 at the center of gravity Cg. . In the embodiment, the center-of-gravity parameters are the distance Lf from the center of gravity Cg to the front wheel axis, the distance Lr from the center of gravity Cg to the rear wheel axis, the distance h from the road surface to the center of gravity Cg, and the mass M at the center of gravity Cg of the vehicle 10.

Here, the load sensor 80i changes its output in accordance with the mass of the occupant who rides on the vehicle 10 and the mass of the luggage loaded on the vehicle 10, and is a detection value detected by the gravity center position estimation unit 4c. The load Fi is output. One or more load sensors 80i are provided in places such as each seat and trunk. That is, the center-of-gravity position estimation unit 4c is based on the load Fi (detected value detected as a change in the center-of-gravity position of the vehicle 10) output from the load sensor 80i and the installation distance Li, Lfb, Lrb, hb, Mb. Thus, Lf, Lr, h, and M are corrected. The vehicle vibration suppression control device 1 includes an installation longitudinal distance Li (i ≧ 1) that is a distance in the longitudinal direction of the vehicle 10 from the center of gravity Cgb of the reference specifications to the load sensor 80i, and from the center of gravity Cgb to the load sensor 80i. A preset vertical distance hi (i ≧ 1) that is a distance in the vertical direction of the vehicle 10 is stored in advance.

Next, a method for correcting the centroid parameter in the centroid position estimating unit 4c will be described. The method for correcting the center-of-gravity parameter is stored in advance in the vehicle vibration suppression control device 1 as a correction execution program, for example, and is repeatedly executed every control cycle. As shown in FIG. 6, the center-of-gravity position estimation unit 4c first determines whether or not the vehicle 10 is stopped (step ST1). Here, the center-of-gravity position estimation unit 4c determines, for example, whether or not the vehicle 10 is stopped based on the average wheel speed r · ω that is output and acquired by the vehicle vibration suppression control device 1. Then, it is determined whether or not the vehicle 10 is stationary.

Next, when it is determined that the vehicle 10 is stopped (Yes at step ST1), the center-of-gravity position estimation unit 4c acquires the load Fi. Here, the center-of-gravity position estimation unit 4c acquires the load Fi output from the load sensor 80i (step ST2).

Next, the center-of-gravity position estimation unit 4c calculates a mass change amount ΔM (step ST3). Here, the center-of-gravity position estimation unit 4c calculates ΔM as a change amount with respect to Mb based on the acquired Fi. The center-of-gravity position estimation unit 4c calculates ΔM based on Fi and the following equation (6). Here, g is a gravitational acceleration.

ΔM = ΣFi / g (6)

Next, the center-of-gravity position estimation unit 4c calculates a change amount ΔL before and after the center-of-gravity position (step ST4). Here, the center-of-gravity position estimation unit 4c calculates ΔL as the amount of change in the front-rear direction of the vehicle 10 with respect to the center-of-gravity Cgb of the reference specifications, based on the acquired Fi, Li, and Mb. The center-of-gravity position estimation unit 4c calculates ΔL based on Fi, Li, Mb, and the following equation (7). Here, Li is positive behind the vehicle 10.

ΔL · Mb = Σ ((Fi / g) · (Li−ΔL)) (7)

Next, the center-of-gravity position estimation unit 4c calculates a center-of-gravity position vertical change amount Δh (step ST5). Here, the center-of-gravity position estimation unit 4c calculates Δh as the amount of change in the vertical direction of the vehicle 10 with respect to the center-of-gravity Cgb of the reference specifications based on the acquired Fi, hi, and Mb. The center-of-gravity position estimation unit 4c calculates Δh based on Fi, hi, Mb, and the following equation (8). Here, hi is positive above the vehicle 10.

Δh · Mb = Σ ((Fi / g) · (hi−Δh)) (8)

Next, the center-of-gravity position estimation unit 4c corrects Lf, Lr, h, and M (step ST6). Here, the center-of-gravity position estimation unit 4c corrects Lf, Lr, h, and M based on the calculated ΔM, ΔL, and ΔH. The center-of-gravity position estimation unit 4c calculates Lf based on ΔL, ΔH, ΔM, Lfb, Lrb, hb, Mb, and the following equations (9), (10), (11), and (12). , Lr, h, M are corrected. That is, Lf, Lr, h, M, that is, the centroid parameter is corrected based on the change in the centroid position.

Lf = Lfb + ΔL (9)
Lr = Lrb−ΔL (10)
h = hb + Δh (11)
M = Mb + ΔM (12)

Then, the vehicle vibration control device 1 updates the stored center-of-gravity parameters Lf, Lr, h, and M to the corrected values. Therefore, the vehicle damping control unit 4 acquires the damping torque based on the dynamic motion model using the corrected center-of-gravity parameter. That is, the vehicle vibration suppression control device 1 performs power control that causes the engine 21 to generate the required torque Te that can be generated by changing the vibration suppression torque based on the position of the center of gravity of the vehicle 10. As a result, the vehicle vibration suppression control device 1 changes the drive torque generated by the engine 21 so that the vibration suppression torque is generated based on the position of the center of gravity of the vehicle 10. Note that if the vehicle center position estimation unit 4c determines that the vehicle 10 is not stopped (No in step ST1), the vehicle vibration damping control device 1 does not update the gravity center parameter.

As described above, the vehicle vibration suppression control device 1 according to the embodiment performs power control that causes the engine 21 to generate the required torque Te that can be generated by changing the vibration suppression torque based on the position of the center of gravity of the vehicle 10. Since the damping torque is acquired based on the dynamic motion model using the center of gravity parameter corrected based on the center of gravity position of the vehicle 10, the change of the center of gravity position (including the change of the mass of the vehicle 10) is also included. Accordingly, the damping torque calculated by the vehicle damping control unit 4b changes, and the required torque Te changes based on the changed damping torque. That is, since the shift of the center of gravity position assumed in the dynamic motion model with respect to the center of gravity position of the actual vehicle 10 can be suppressed, vibration suppression is performed based on a highly accurate mechanical motion model corresponding to the actual vehicle 10. Control can be performed. Therefore, a vibration reduction effect can be sufficiently obtained by the vibration suppression control performed by the vehicle vibration suppression control device 1.

In the above embodiment, the load sensor 80i is used as the gravity center position changing means, but the present invention is not limited to this. Center-of-gravity position detection means detects presence / absence of an occupant seated in the vehicle, for example, a seat detection switch that is turned on when the occupant is seated, or a seat belt connection switch that is turned on when the seat belt is worn by the occupant It may be. In the case of these barycentric position detecting means, the barycentric position estimating unit 4c outputs whether or not a passenger is seated as a detected value. The vehicle vibration damping control device 1 stores in advance the mass Madd per passenger and the installation longitudinal distance Li (i ≧ 1) and the set vertical distance hi (i ≧ 1) as in the case of the load sensor 80i. Has been. Therefore, the center-of-gravity position estimation unit 4c has the number N of passengers seated on ΔM, ΔL, and ΔH, Madd, Mb, Li, hi, and the following equations (13), (14), (15 ), And Lf, Lr, h, and M may be corrected based on the calculated ΔM, ΔL, and Δh. As a result, even if an inexpensive center-of-gravity position detecting means is used as compared with the load sensor 80i or the like, the shift of the center-of-gravity position assumed in the dynamic motion model with respect to the actual center-of-gravity position of the vehicle 10 can be suppressed. The vibration suppression control can be performed based on a highly accurate dynamic motion model corresponding to the actual vehicle 10. Therefore, a vibration reduction effect can be sufficiently obtained by the vibration suppression control performed by the vehicle vibration suppression control device 1.

ΔM = Σ (Madd · N) (13)
ΔL · Mb = Σ (Madd · (Li−ΔL)) (14)
Δh · Mb = Σ (Madd · (hi−Δh)) (15)

The center-of-gravity position detection means detects a change in the vehicle height before and after the vehicle 10, for example, a front vehicle height that detects a front vehicle height change amount Δhf that is a change in the vehicle height of the vehicle 10 on the front wheel axle. A rear front vehicle height sensor or the like that detects a rear vehicle height change amount Δhr that is a change amount of the vehicle height of the vehicle 10 on the sensor and the rear wheel shaft may be used. In the case of this barycentric position detecting means, Δhf and Δhr are output as detected values to the barycentric position estimating unit 4c. First, the center-of-gravity position estimation unit 4c, based on Δhf, Δhr, and the following formulas (16) and (17), the front mass change amount ΔMf that is the change amount of the mass of the vehicle 10 on the front wheel shaft and the rear A rear mass change amount ΔMr, which is a change amount of the mass of the vehicle 10 on the wheel shaft, is calculated.

ΔMf = Δhf · Kf / g (16)
ΔMr = Δhr · Kr / g (17)

Next, the center-of-gravity position estimation unit 4c sets ΔM as the sum of the calculated ΔMf and ΔMr (ΔM = ΔMf + ΔMr), ΔL becomes ΔMf, ΔMr, Lf, Lr, and the following equation (18): May be calculated, and Lf, Lr, and M may be corrected based on the calculated ΔM and ΔL. As a result, even if an inexpensive center-of-gravity position detecting means is used as compared with the load sensor 80i or the like, the shift of the center-of-gravity position assumed in the dynamic motion model with respect to the actual center-of-gravity position of the vehicle 10 can be suppressed. The vibration suppression control can be performed based on a highly accurate dynamic motion model corresponding to the actual vehicle 10. Therefore, a vibration reduction effect can be sufficiently obtained by the vibration suppression control performed by the vehicle vibration suppression control device 1. In the above description, the change in the mass before and after the vehicle 10 is calculated based on the change in the vehicle height before and after the vehicle 10. However, the center of gravity position detecting means directly detects the change in the mass before and after the vehicle 10. It may be used.

ΔL · Mb = ΔMf (Lf + ΔL) + ΔMr (Lr−ΔL) (18)

Moreover, in the said embodiment, although vibration suppression control is performed according to the change of a gravity center position by applying a load to the vehicle 10, this invention is not limited to this and comprises the vehicle 10. The present invention may be applied when the position of the center of gravity changes due to a change in the position of the part, for example, the roof of an open car, relative to the vehicle 10. Further, the vibration suppression control is performed according to the change in the center of gravity position when the vehicle 10 is stationary, but the present invention is not limited to this, and the center of gravity position changes due to the behavior change of the vehicle 10. You may apply in. In this case, the center-of-gravity position estimation unit 4c changes the mass of the vehicle 10 before and after the vehicle 10 based on the acceleration that is the detection value output from the acceleration sensor that detects the acceleration of the vehicle 10 provided in the vehicle 10, for example. It may be calculated. Further, when the driving torque of the engine 21 is the same, the mass increases as the acceleration of the vehicle 10 decreases. Therefore, the calculation of the mass change amount ΔM, that is, the estimation of the actual mass M of the vehicle 10 is not limited to the calculation method in the above embodiment, but is based on the driving torque of the engine 21 and the acceleration of the vehicle 10. It may be done.

Further, in the above-described embodiment, the sprung mass damping control has been described as being performed using the theory of an optimal regulator assuming a sprung or sprung / unsprung motion model as a motion model. Of those other than those described above, a motion model using a center of gravity parameter or a control method other than the optimal regulator may be used.

In the above embodiment, the case where the power control of the engine 21 is performed based on the driving request of the driver has been described, but the present invention is not limited to this. For example, the vehicle 10 may include an automatic travel control device and perform power control based on a required torque calculated when the engine 21 is controlled in the automatic travel control.

In the above embodiment, the control of the power generated by the power source mounted on the vehicle 10 based on the required torque Te has been described, but the present invention is not limited to this. For example, when the power source is a gasoline engine, a target intake air amount that is a value that affects the required torque or a target throttle opening that is a valve opening of a throttle valve may be used. When the power source is a diesel engine, the required torque or a target fuel injection amount that is a value that affects the required torque may be used. Further, when the power source is a motor, a required torque, a target current value, or the like may be used. Furthermore, a target driving force that acts on the vehicle 10 may be used regardless of the type of power source.

As described above, the vehicle damping control device and the vehicle damping control device control method according to the present invention are useful for the vehicle damping control device and the vehicle damping control device control method for suppressing sprung vibration, In particular, it is suitable for obtaining a sufficient vibration reduction effect.

DESCRIPTION OF SYMBOLS 1 Vehicle damping control apparatus 2 Braking control apparatus 3 Drive control part 3a Request torque calculation part 3b Adder 3c Control command determination part 4 Vehicle damping control part 4a Feedforward control part 4b Feedback control part 4c Center-of-gravity position estimation part 4d Drive torque Conversion unit 4e Wheel torque conversion unit 4f Motion model unit 4g FF secondary regulator unit 4h Wheel torque estimation unit 4i FB secondary regulator unit 4k Adder 4l FF control correction unit 4m FF control gain setting unit 4n FB control correction unit 4o FB control Gain setting unit 10 Vehicle 20 Drive device 21 Engine (power source)
22 AT
23 Differential gear unit 30FL, 30FR, 30RL, 30RR Wheel 40FL, 40FR, 40RL, 40RR Wheel speed sensor 50 ECU
60 Accelerator pedal 70 Pedal sensor 80i Load sensor

Claims

In a vehicle vibration suppression control device that generates a vibration suppression torque that suppresses sprung vibration on a drive wheel that transmits the power by controlling power generated by a power source mounted on the vehicle.
A vehicle damping control device, wherein the power is changed so that the damping torque is generated based on a position of the center of gravity of the vehicle.
The vibration damping torque is generated by controlling the power based on a dynamic motion model based on at least a sprung vibration of the vehicle including a parameter related to a center of gravity position of the vehicle.
The vehicle damping control device according to claim 1, wherein the parameter is corrected based on a change in a center of gravity position of the vehicle.
3. The vehicle vibration control according to claim 1, wherein the center-of-gravity position of the vehicle is estimated based on a detected value detected by a center-of-gravity position change detecting unit that detects a change in the center-of-gravity position of the vehicle. Control device.
The vehicle vibration damping control device according to claim 3, wherein the center-of-gravity position change detecting means detects the presence or absence of a seat of an occupant riding in the vehicle.
In a control method of a vehicle vibration suppression control device that generates a vibration suppression torque that suppresses sprung vibration on a drive wheel that transmits the power by controlling power generated by a power source mounted on the vehicle.
A control method for a vehicle vibration control device, characterized in that the power for generating a vibration suppression torque changed based on a position of a center of gravity of the vehicle is generated.