JP2936640B2 - Comprehensive control system for auxiliary steering angle and wheel load distribution - Google Patents

Abstract

PURPOSE:To make the total control effect of both control devices optimum in a vehicle mounted simultaneously with an auxiliary steering angle control device and a wheel load distribution control device by discriminating the vehicle state region by parameters including lateral largeness of control effect. CONSTITUTION:In an integrated control device comprising an auxiliary steering angle control device (a) for controlling the steering angle of at least either front wheels or rear wheels at the time of steering the front wheels, and a wheel load distribution control device (b) for controlling the load moving quantity distribution of each wheel, mounted on a vehicle, there is provided a lateral acceleration detecting means (d) for detecting the lateral acceleration YG acting upon the vehicle. The auxiliary steering angle control sensitivity alphas and the wheel load distribution control sensitivity alphaR are set by an integrated control sensitivity setting means (e) in such a way that the wheel load distribution control sensitivity alphaR becomes larger in relation to the auxiliary steering angle control sensitivity alphaS as the lateral acceleration detection value becomes larger. The total control effect of both control devices (a), (b) can be thereby made optimum while preventing the restriction of control quantity on the control device side with larger control effect during the simultaneous operation of both control devices (a), (b).

Description

Description: TECHNICAL FIELD The present invention relates to an integrated control device for auxiliary steering angle and wheel load distribution.

2. Description of the Related Art Conventionally, as a rear wheel steering angle control device which is an example of an auxiliary steering angle control device, for example, a device described in JP-A-59-77968 is known. At low vehicle speed or when the front wheel steering angle is large, the rear wheels are steered in the opposite phase, and at high vehicle speed or when the front wheel steering angle is small, the rear wheels are steered in phase. The contents to improve the steering performance are shown.

Conventionally, as a suspension control device which is an example of a wheel load distribution control device, for example, Japanese Patent Application Laid-Open No. 62-292516
The device described in Japanese Patent Application Publication No. H11-209,991 is known. According to this conventional source, a vehicle attitude change due to a roll, pitch, bounce, and the like of a vehicle is continuously and widely changed by changing a spring constant or a damping constant of a suspension. Are shown.

(Problems to be Solved by the Invention) However, when the rear wheel steering angle control device and the suspension control device are simultaneously mounted on one vehicle, the auxiliary steering angle control sensitivity and the wheel load distribution control sensitivity are independently set. If the rear wheel steering angle control and the wheel load distribution control are performed independently based on the set sensitivity and the set sensitivity, the control effect of the vehicle state area where the control effect of the auxiliary steering angle control is large and the control effect of the wheel load distribution control are originally large. However, since this point is not considered at all even though the vehicle state area is different from the large vehicle state area, the total control effect of the two control devices is not optimal.

In addition, when the rear wheel steering angle control and the wheel load distribution control are performed simultaneously, the control amount is the same as when the vehicle is mounted alone and the total energy consumption is reduced even in the vehicle state where one of the control effects is small. In a vehicle equipped with a plurality of control devices as described above, when the total energy consumption is limited for reasons such as fuel efficiency, the control amount on the side where the control effect is large may be controlled. .

Therefore, it is conceivable to simply perform cooperative control to improve a certain performance or perform control to compensate for the other performance degradation by changing one control and link the controls with each other. In this case, the effect can be obtained only for this purpose, and the optimization of the total control effect cannot be achieved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In a general control device for a vehicle in which an auxiliary steering angle control device and a wheel load distribution control device are simultaneously mounted, control is performed when both control devices are simultaneously operated. It is an object of the present invention to optimize the total control effect of both control devices while preventing the device amount from being controlled on the device side having a large effect.

(Means for Solving the Problems) In order to solve the problems described above, the integrated control device for assisting steering angle and wheel load distribution according to the present invention has a large control effect of assisting steering angle control and a vehicle state area and wheel load distribution control. A vehicle state region having a large control effect is distinguished by the same parameter including at least the lateral acceleration, and the control sensitivity is changed according to the magnitude of the control effect.

That is, as shown in the claim correspondence diagram of FIG. 1, in the invention according to claim 1, an auxiliary steering angle control device a for controlling at least one of the front wheels or the rear wheels during steering of the front wheels, and a load on each wheel. Wheel load distribution control device b for controlling distribution of moving amount
When the lateral acceleration detecting means d for detecting a lateral acceleration Y _G acting on the vehicle, the auxiliary steering angle control proportional constant when representing the auxiliary steering angle target value obtained by multiplying a proportional constant and basic control steering angle formula Sensitivity α _S is defined, and the proportional constant when the wheel load distribution target value is represented by an equation obtained by multiplying the proportional constant by the basic wheel load distribution is defined as the wheel load distribution control sensitivity α _R. Overall control sensitivity setting the auxiliary steering angle control sensitivity alpha _S and wheel load distribution control sensitivity alpha _S to relatively increase the wheel load distribution control sensitivity alpha _R relative to the larger value the auxiliary steering angle control sensitivity alpha _S And setting means e.

Further, in the invention according to claim 2, an auxiliary steering angle control device a for controlling at least one steering angle of the front wheel or the rear wheel at the time of front wheel steering, and a wheel load distribution control device for controlling distribution of a load movement amount of each wheel. and b, a longitudinal acceleration detecting means c for detecting a longitudinal acceleration X _G acting on the vehicle, the lateral acceleration acting on the vehicle
A lateral acceleration detecting means d for detecting the Y _G, the proportionality constant when expressed auxiliary steering angle target value proportional constant and the basic control and the steering angle multiplied by the formula was defined as the auxiliary steering angle control sensitivity alpha _S, wheels when the proportional constant when representing the load distribution target value obtained by multiplying a proportional constant and basic wheel load distribution formula defined as wheel load distribution control sensitivity alpha _R, the square of the square and the lateral acceleration detected value of the longitudinal acceleration detected value Calculates the sum of (X _G ² + Y _G ² ) and sums this (X _G ² + Y _G ² )
Auxiliary steering angle control sensitivity alpha _S and wheel load distribution control sensitivity so that the value of the ratio of the wheel load distribution control feeling degree _{α R (α R / α S} ) is increased relative to the higher the value the auxiliary steering angle control sensitivity alpha _S α _R
And a total control sensitivity setting means e for setting

(Operation) According to the first aspect of the present invention, when the vehicle is running, the total control sensitivity setting means e sets the auxiliary steering angle target value by a formula obtained by multiplying the proportional constant by the basic control steering angle. the proportionality constant is defined as the auxiliary steering angle control sensitivity alpha _S, defining the proportionality constant in the case of representing the wheel load distribution target value by the formula obtained by multiplying a proportional constant and basic wheel load distribution between the wheel load distribution control sensitivity alpha _R when, as the value of the lateral acceleration detection value is larger auxiliary steering angle control sensitivity alpha _S wheel load distribution control sensitivity alpha auxiliary steering angle control sensitivity to relatively large _R alpha _S and wheel load distribution control sensitivity alpha relative _R is set.

According to the second aspect of the present invention, when the vehicle is running, the total control sensitivity setting means e detects the square of the longitudinal acceleration detection value detected by the longitudinal acceleration detection means c and the lateral acceleration detection means d. the sum of the squares of the lateral acceleration detection value _{^{(X G 2 + Y G 2}} ) is calculated, the sum _{^{(X G 2 + Y G 2}} ) wheel load distribution control sensitivity higher the value for the auxiliary steering angle control sensitivity alpha _S of alpha _R the ratio auxiliary steering angle control sensitivity so that the value of (α _R / α _S) increases alpha _S and wheel load distribution control sensitivity alpha _R is set for.

In other words, the two control sensitivities α _S and α _R are set and changed using Y _G or (X _G ² + Y _G ² ) as a parameter.
This is for the following reason.

Wheel load distribution control is to control the cornering power of the tire by controlling the amount of load movement between the left and right wheels or between the front and rear wheels, so the control effect is large in the area where the load movement is large, and the control effect is large. The region can be referred to as a region where the longitudinal acceleration and the lateral acceleration are large.

On the other hand, the auxiliary steering angle control has an effect in the cornering power characteristic of the tire from a linear region to a non-linear region, but since the effect of other control devices is large in the non-linear region, the control effect is relatively large in the linear region of the tire characteristic. A region that is large and has a large control effect can be regarded as a region where the longitudinal acceleration and the lateral acceleration in which the wheel load distribution movement is small are small.

Therefore, by using Y _G or (X _G ² + Y _G ² ) as a parameter, it is possible to distinguish areas according to the magnitude of the control effect.
The Y _G or ^{_{(X G 2 + Y G 2}} ) during running value is small, that the auxiliary steering angle control sensitivity alpha _S is relatively enhanced with respect to the wheel load compounding control sensitivity alpha _R, wheel load compounding control Therefore, the change in the steering characteristic due to the above is suppressed to a small extent, and the auxiliary steering angle control having a large control effect is fully utilized.

On the other hand, during the running value is large Y _G or ^{_{(X G 2 + Y G 2}} ), by the wheel load compounding control sensitivity alpha _R is relatively enhanced with respect to the auxiliary steering angle control sensitivity alpha _S, auxiliary steering The change in the amount of movement of the wheel load due to the change in the side slip angle of the tire accompanying the angle control is suppressed small, and the wheel load distribution control with a large control effect is fully utilized, and both control devices a, b Thus, the control effect can be totally optimized.

Further, even if the total energy consumption is limited due to reasons such as fuel efficiency, the energy consumption on the side of the device having a small control effect is reduced by the change control of the two control sensitivities α _S and α _R. Among them, the control amount limitation on the side of the device having a large control effect is prevented.

First Embodiment First, the configuration will be described.

FIG. 2 shows a front and rear wheel steering angle control device (an example of an auxiliary steering angle control device), a front and rear wheel driving force distribution control device (an example of a braking / driving force control device), and an active suspension control device (an example of a wheel load distribution control device). FIG. 1 is an overall system diagram showing a vehicle simultaneously mounted with the above.

The vehicle equipped with each control system is a torque split four-wheel drive vehicle based on a rear wheel drive, and the right and left rear wheels 1R, 1L are equipped with an engine 2, a transmission 3, a rear propeller shaft 3, a rear differential 5, Engine driving force is transmitted via rear drive shafts 6R and 6L.

The engine driving force is transmitted to the left and right front wheels 7R, 7L from a transfer 8 provided in the middle of the rear propeller shaft 4 via a front propeller shaft 9, a front differential 10, and left and right front drive shafts 11R, 11L.

Further, between the front steering gear device 12 for steering the front wheels 7R, 7L and the left and right rear wheels 1R, 1L, front and rear wheel steering for giving an auxiliary steering angle to the front wheels 7R, 7L and the rear wheels 1R, 1L by a piston stroke by the supplied hydraulic pressure. A front wheel hydraulic power cylinder 13 and a rear wheel hydraulic power cylinder 14 are provided as angle control actuators.

Further, the transfer 8 has a built-in hydraulic multi-plate clutch 15 as a front and rear wheel driving force distribution control actuator for giving a variable transmission torque to the front wheels by engagement pressure control.

In addition, a hydraulic cylinder as an active suspension control actuator between the sprung and unsprung positions of each wheel that actively suppresses vehicle body swing by independent control of supply hydraulic pressure
16FR, 16FL, 16RR, 16RL are provided.

The supply hydraulic pressure to the front wheel hydraulic power cylinder 13 and the rear wheel hydraulic power cylinder 14 is controlled by a front wheel hydraulic control valve 17F.
And a valve operation control command from the steering angle control controller 18 for the rear wheel hydraulic control valve 17R.A detection signal is input to the steering angle control controller 18 from a front wheel steering angle sensor 19, a vehicle speed sensor 20, and the like. In addition, model adaptation control of yaw rate for obtaining a desired yaw rate response at the time of turning, phase inversion control for achieving both steering response and steering stability, and the like are performed.

The control of the supply hydraulic pressure to the hydraulic multi-plate clutch 15 is performed by a valve operation control command from the driving force distribution controller 22 to the driving force distribution control valve 21, and the driving force distribution controller 22 includes a right front wheel rotation sensor 23, Left front wheel rotation sensor 24, Right rear wheel rotation sensor 25, Left rear wheel rotation sensor 2
6, Detection signals from the lateral acceleration sensor 27 etc. are input and the driving force distribution is changed from rear wheel drive (0: 100) to rigid 4WD (50:50)
By the above-described front and rear wheel driving force distribution control that continuously controls the vehicle, for example, while starting or accelerating, the driving wheel distribution is reduced by reducing the driving force distribution to the front wheels during turning to reduce rear wheel driving tendency. For example, control for improving both driving performance and turning performance is performed.

The hydraulic pressure supplied to the hydraulic cylinders 16FR, 16FL, 16RR, 16RL is controlled by a right front wheel control valve 28FR, a left front wheel control valve 28FL,
The suspension control controller 29 controls the right rear wheel control valve 28RR and the left rear wheel control valve 28RL according to valve operation control commands. The suspension control controller 29 includes a vertical acceleration sensor 30, a lateral acceleration sensor 2
7, detection signals from the longitudinal acceleration sensor 31, the vehicle height sensor 32, and the like are input, and for example, vehicle body vertical restraint control, vehicle body roll restraint control, vehicle pitching restraint control, vehicle height change restraint control, etc. Done.

And the longitudinal acceleration sensor 31 (longitudinal acceleration detecting means)
And the detection signal from the lateral acceleration sensor 27 (lateral acceleration detecting means) and the switch signal from the manual switch 33 are input to determine the magnitude of the control effect according to the vehicle state (X _G ² +
Y _G ² ) and (X _G / Y _G ) are distinguished as parameters, and the auxiliary steering angle control sensitivity α _S , the driving force distribution control sensitivity α _T, and the wheel overload distribution control sensitivity α _R that are optimal for the vehicle state at that time are determined. There is provided a general control controller 34 (general control sensitivity setting means) which outputs the obtained control sensitivities α _S , α _T , α _R to the respective controllers 18, 22, 29. The manual switch 33
Is a switch for changing the control characteristic mode in order to reflect the driver's intention and preference. In the embodiment, two modes are set, a mode A emphasizing driving force characteristics and a mode B emphasizing turning characteristics.

FIG. 3 shows a specific example of the front and rear wheel steering angle control system, FIG. 4 shows a specific example of the front and rear wheel driving force distribution system, and FIG.
The figure shows a specific example of an active suspension control system, all of which are well known and detailed description is omitted.

Next, a basic concept regarding control sensitivity setting in the present embodiment will be described.

^{_{(I) (X G 2 + Y G}} 2), (X G / Y G) first reason for a parameter for distinguishing the magnitude region of the control ^{_{effect, (X G 2 + Y G}} 2), (X G / Y G) each control sensitivity alpha _S as a parameter for distinguishing the magnitude region of the control effect, α _T, α _R
Is changed and set for the following reason.

・ Since the braking / driving force control is a slip ratio control based on the distribution of the driving force or the braking force, the driving force or the braking force is large, and the control effect is large in a region where the slip ratio is large. It can be called an acceleration region or a deceleration region where the acceleration is large.

In the wheel load distribution control, since the cornering power of the tire is controlled by controlling the amount of load movement between the left and right wheels (or between the front and rear wheels), the control effect is large in an area where the load movement is large.

That is, it is a region where the lateral acceleration and the longitudinal acceleration are large.
However, emphasis is placed on lateral acceleration rather than longitudinal acceleration, since lateral acceleration often occurs more steadily.

-The auxiliary steering angle control has an effect from the linear range to the non-linear range in the cornering power characteristics of the tire.However, in the non-linear range, the control effect is relatively large in the linear region of the tire characteristics because the effect of other control devices is large. A region that is large and has a large control effect can be regarded as a region where the longitudinal acceleration and the lateral acceleration in which the wheel load movement is small are small.

Accordingly, FIG. 6 is a conceptual diagram showing a vehicle state region having a large control effect by the respective control sensitivities α _S , α _T , and α _R.

(B) Problems when control sensitivity is fixed value a) Problems in the area where (X _G ² + Y _G ² ) is good at assisting steering angle control ・ About braking / driving force control Basically, control is not performed in this area. It is unnecessary and wastes power, and despite the desire to increase the auxiliary steering angle control effect by applying a lot of power (for example, hydraulic pressure during hydraulic control) to the auxiliary steering angle control, due to reasons such as fuel efficiency, Since the total output is limited, the power required by the auxiliary steering angle control device cannot be obtained.

In terms of performance, the cornering power of the front and rear wheels changes in conjunction with the change in the wheel load distribution, and the control effect of the auxiliary steering angle control device that controls the cornering power as if there is no change is impaired.

・ About wheel load distribution control The point that the power is wasted and the power of the auxiliary steering angle control device cannot be obtained is the same as the braking / driving force control.

In terms of performance, the independent control of the auxiliary steering angle control is controlled by assuming that the steering characteristic has a constant value, but the steering characteristic changes due to the wheel load distribution control (specifically, the front and rear cornering powers). ), The characteristic originally intended by the auxiliary steering angle control cannot be obtained.

b) (X _G ² + Y _G ² ) is good at wheel load distribution control,
Problems in the area where (X _G / Y _G ) is small ・ Auxiliary steering angle control The point that the power is wasted and the power of the wheel load distribution control device cannot be obtained is the same as the others.

In terms of performance, for example, the side slip angle of the tire changes due to the control of the auxiliary steering angle, the direction of the lateral force and the longitudinal force acting on the tire changes, and the moving amount of the wheel load changes (rear wheel movement). , The sideslip angle is directed to the inside of the turn, the wheel load distribution of the front inner wheel decreases, and the wheel load of the rear outer wheel increases.) Therefore, the state before the control of the wheel load distribution control is as follows.
The control depends on the presence or absence of the auxiliary steering angle control, and the intended control in the wheel load distribution control cannot be properly performed.

・ About braking / driving force control The point that the power is wasted and the power of the wheel load distribution control device cannot be obtained is the same as the others.

In terms of performance, for example, in the front and rear wheel driving force distribution control, the slip ratio of the front and rear wheels fluctuates to change the driving force distribution. Despite the desire to optimize the cornering force generated by each wheel by controlling the steering characteristic by the wheel load distribution control, the cornering force deviates from the optimum value due to the change in the slip ratio.

c) Control (X _G ² + Y _G ² ) which is good at drive control is large, and (X _G
Problems in the region where / Y _G ) is large ・ Auxiliary steering angle control The point that the power is wasted and the power of the braking / driving force control device cannot be obtained is the same as the others.

In terms of performance, for example, the side slip angle of the tire changes due to the control of the auxiliary steering angle, the direction of the lateral force and the longitudinal force acting on the tire changes, and the moving amount of the wheel load changes (rear wheel movement). , The sideslip angle is directed toward the inside of the turn, the wheel load on the front inner wheel decreases, and the front inner wheel spins.)

Therefore, the slip ratio of each wheel changes due to the change in the wheel load, and finally, the difference between the front and rear wheel rotational speeds differs depending on the presence or absence of the auxiliary steering angle control, so that the intended control cannot be performed.

・ About wheel load distribution control The point that the power is wasted and the power of the braking / driving force control device cannot be obtained is the same as the others.

In terms of performance, for example, when the wheel load distribution of one wheel decreases due to the wheel load distribution control, the slip ratio of the tire increases, and in the worst case, the tire slips and the rotational speed difference between the front and rear wheels increases. Since it changes depending on the presence or absence of the load distribution control, the intended control cannot be performed.

 Next, the operation will be described.

FIG. 7 is a flow chart showing the flow of the control sensitivity setting processing operation in the general control controller 34 which sets the respective control sensitivities α _S , α _T , α _R and outputs them to the controllers 18, 22, 29.
Hereinafter, each step will be described.

In step 101, a switch signal from the manual switch 33 and sensor signals from the longitudinal acceleration sensor 31 and the lateral acceleration sensor 27 are read.

In step 102, the square of the longitudinal acceleration X _G and the lateral acceleration Y _G
Is calculated.

In step 103, it is determined whether the value of (X _G ² + Y _G ² ) is equal to or greater than a predetermined value.

If the value of (X _G ² + Y _G ² ) is less than the predetermined value, the process proceeds to step 108, where the auxiliary steering angle control sensitivity α _S , the driving force distribution control sensitivity α _T , and the wheel load distribution control sensitivity α _R Is α
_S1, alpha _T1, sets the alpha _R1.

Here, α _T1 and α _R1 are set to extremely small values with respect to α _{S1 so} that the auxiliary steering angle control effect is increased.
For example, α _S1 = 1 and α _T1 , α _R1 ≒ 0 may be set.

On the other hand, if it is determined in step 103 that the value of (X _G ² + Y _G ² ) is equal to or greater than the predetermined value, the process proceeds to step 104 and subsequent steps.

In step 104, (X
The values of the auxiliary steering angle control sensitivity α _S and the control gain K _S are calculated from the auxiliary steering angle control sensitivity characteristic map and the control gain characteristic map for the value of _G ² + Y _G ² ).

Although these characteristic map is selected by characteristic mode by manual switch 33, basically, the auxiliary steering angle control sensitivity alpha _{S ^{is, (X G 2 + Y G}} 2) Higher the smaller increase (right downward ), The control gain K _S is (X _G ² + Y _G ² )
The characteristic is set to increase (increase right) as the value increases.

In step 105, the value of (X _G / Y _G ) is calculated.

In step 106, (X
The values of the driving force distribution basic control sensitivity α _TO and the wheel load distribution basic control sensitivity α _RO are calculated from the driving force distribution control sensitivity characteristic map and the wheel load distribution control sensitivity characteristic map for the value of _G / Y _G ).

It should be noted that these characteristic maps are selected in the characteristic mode by the manual switch 33. Basically, the driving force distribution basic control sensitivity α _TO increases as the value of (X _G / Y _G ) increases (increases to the right). ), Wheel load distribution basic control sensitivity α
_RO is set so that it becomes smaller (lower right) as the value of (X _G / Y _G ) becomes larger.

In step 107, the basic control sensitivities α _TO and α _RO obtained in step 106 are corrected by the following equation, and the driving force distribution control sensitivity α _T and the wheel load distribution control sensitivity α _R are calculated.

α _T = α _TO · K _S α _R = α _RO · K _{S In} step 109, the control sensitivities α _S , α _T , α obtained in step 104 and step 107 or step 108 are obtained.
_R is output to the steering angle controller 18, the driving force distribution controller 22, and the suspension control controller 29, respectively.

Based on the settings of the control sensitivities α _S , α _T , and α _R described above, the controllers 18, 22, and 29 perform the following control.

As shown in the following equation, the steering angle control controller 18 multiplies the basic control steering angles f _sf and f _sr by the auxiliary steering angle control sensitivity α _S to obtain the front wheel auxiliary steering angle target value δ _F ^* and the rear wheel is an auxiliary steering angle target value [delta] _R ^*, the target value δ _F ^*, δ _R ^*
Is output to the front wheel steering angle control valve 17F and the rear wheel steering angle control valve 17R.

^{_{δ F * = α S · f}} sf (θ, V) δ R * = α S · f sf (θ, V) in the driving force distribution controller 22, as shown in the following formula, the basic front wheel side driving force distribution ratio the value obtained by multiplying the driving force distribution control sensitivity alpha _T to f _T is the driving force distribution wheel ratio target value T _F ^*
A command signal for obtaining the target value T _F ^* is output to the driving force distribution control valve 21.

T _F ^* = α _T · f _T (ΔN, Y _G ) where ΔN is the difference between the front and rear wheel rotation speeds, and the rear wheel rotation speed Nr and the front wheel rotation are determined by signals from the rotation sensors 23, 24, 25, and 26. The speed Nf is obtained by the following equation which takes the difference between them.

ΔN = Nr−Nf In the suspension control controller 29, as shown in the following equation, the value obtained by multiplying the basic wheel load distribution ratio f _R by the wheel load distribution control sensitivity α _R is equal to the wheel load distribution ratio target value R _S ^* . Is done.

R _S ^* = α _R · f _R (Z _G , X _G , Y _G , S) As described above, the front and rear wheels corresponding to the embodiment of the integrated control device for auxiliary steering angle and wheel load distribution according to the present invention. When the steering angle control and the front and rear wheel drive force distribution control are viewed, the following effects are exhibited.

By using (X _G ² + Y _G ² ) as a parameter, areas can be distinguished according to the magnitude of the control effect, and as shown in the characteristic map of FIG. 8, the value of (X _G ² + Y _G ² ) is small. during running, the auxiliary steering angle control sensitivity alpha _S is turned into the relatively raised against the wheel load distribution control sensitivity alpha _R, change in accompanying steering characteristic in the wheel load distribution control is kept small, control effect The large front and rear wheel steering angle control is fully utilized.

^{_{Further, (X G 2 + Y G}} 2) When the value of a large travel, that the wheel load distribution control sensitivity alpha _R is relatively enhanced with respect to the auxiliary steering angle control sensitivity alpha _S, the auxiliary steering angle control A change in the amount of movement of the wheel load due to a change in the side slip angle of the accompanying tire is suppressed to a small extent, and the active suspension control with a large control effect is sufficiently utilized.

That is, optimization of the total control effect by the control devices for the auxiliary steering angle and the wheel load distribution is achieved.

Even if the total energy consumption is limited due to reasons such as fuel consumption, the energy consumption on the side of the device where the control effect is small is reduced by the change control of both control sensitivities α _S , α _R , so the auxiliary steering angle and drive power distribution Of the two control devices, the control amount limitation on the device having the greater control effect is prevented.

A manual switch 33 is provided to enable selection of either the driving force characteristic emphasis mode A or the turning performance emphasis mode B, as shown in FIGS. 8 and 9, to meet the driver's preference and traveling road surface. In this way, the performance of the mounting device can be brought out.

(Second Embodiment) Next, a description will be given of an integrated control device for auxiliary steering angle and wheel load distribution according to a second embodiment corresponding to the first aspect of the present invention.

In the first embodiment, since a system comprising a longitudinal force control device, an example of determining the magnitude of the control sensitivity by both of the longitudinal acceleration X _G and the lateral acceleration Y _G, the second embodiment auxiliary a vehicle in which two devices with the steering angle controller and the wheel load distribution control device mounted simultaneously, as described in claim 1, without detecting the longitudinal acceleration X _G, only the lateral acceleration Y _G detected and is an example of to set an auxiliary steering angle control sensitivity alpha _S and wheel load distribution control sensitivity alpha _R.

In terms of configuration, in the apparatus of the first embodiment, the driving force distribution control system is omitted, and the other configuration is not changed.

Next, FIG. 10 shows a general controller 34 of the second embodiment.
Each step will be described below with reference to a flowchart showing the flow of the control sensitivity setting processing operation performed in step (a).

In step 201, the lateral acceleration Y _G
Is read.

In step 202, the lateral acceleration Y auxiliary steering angle control sensitivity alpha _S and wheel load distribution control sensitivity according to the control sensitivity characteristic map that is described in the stearyl frame based on the _G alpha _R is determined.

That is, in the low longitudinal acceleration zone wheel load distribution control sensitivity alpha _R than the auxiliary steering angle control sensitivity alpha _S is the increased value, the wheel load distribution control sensitivity alpha _R than the auxiliary steering angle control sensitivity alpha _S in the high longitudinal acceleration region is Higher value.

In step 203, the two control sensitivities α _S and α _R determined in step 202 are output to the steering angle controller 18 and the suspension controller 29.

Therefore, as in the first embodiment, the total control effect of the two control devices is optimized while preventing the control amount from being limited on the side of the device having a large control effect when both control devices operate simultaneously. I can do it.

As described above, the embodiments have been described based on the drawings. However, the specific configuration is not limited to the embodiments, and even if there is a design change or the like without departing from the gist of the present invention, it is included in the present invention. .

For example, in the embodiment, the example of the characteristic (FIG. 8) where the control sensitivities α _S and α _R intersect is shown. However, it is not always necessary that both characteristics intersect, and as shown in FIG. 9, (X _G ² When a characteristic graph of (α _R / α _S ) with respect to (+ Y _G ² ) is described, (X _G ² + Y
_G ² values of) are included in the larger the (α _R / α _S) of the auxiliary steering angle control so that the value becomes greater sensitivity alpha _S and wheel load control sensitivity alpha present invention is set to _R. That is, if the graph of (α _R / α _S ) satisfies that the graph is a right-upward characteristic, each control sensitivity characteristic map satisfies the claim whether it is convex upward or downward.

Further, in the present embodiment, the system including the driving force distribution control device has been described. However, it is needless to say that the present invention can be applied to a vehicle not equipped with the driving force distribution control device. The present invention can be applied to a vehicle equipped with a wheel load distribution control device at the same time.

Further, as an auxiliary steering angle control device, an example has been described in which the steering angle is controlled for both the front and rear wheels in the embodiment, but a device for controlling the auxiliary steering angle only for the rear wheel or the front wheel may be used.

In addition, as an example of the wheel load distribution control device, both the roll stiffness and the pitch stiffness can be changed by the hydraulic active suspension control system. A roll stiffness distribution control system that performs the control, a pitch stiffness distribution control system that controls only the pitch stiffness distribution, a control system that changes one of the spring constant and the damping constant, and the like may be used.

(Effects of the Invention) As described above, according to the present invention, the control effect of the auxiliary steering angle control is provided in the integrated control device of the vehicle in which the auxiliary steering angle control device and the wheel load distribution control device are simultaneously mounted. Is distinguished from the vehicle state area where the vehicle load is large and the vehicle state area where the control effect of the wheel load distribution control is large by the same parameter including at least the lateral acceleration, and the auxiliary steering angle target value is multiplied by the proportional constant and the basic control steering angle. the proportionality constant when expressed is defined as the auxiliary steering angle control sensitivity alpha _S, wheel load distribution control sensitivity proportional constant when representing the wheel load distribution target value by the formula obtained by multiplying a proportional constant and basic wheel load distribution alpha When defined as _R ,
Since the control sensitivity is changed according to the magnitude of the control effect, the total control by both control devices is prevented while preventing the control amount from being limited on the side of the control effect having a large control effect when both control devices operate simultaneously. The effect that the control effect can be optimized can be obtained.

[Brief description of the drawings]

FIG. 1 is a claim correspondence diagram showing an integrated control device for auxiliary steering angle and wheel load distribution according to the present invention, and FIG. 2 is a front and rear wheel steering angle control device (an example of an auxiliary steering angle control device) and front and rear wheel driving force distribution control. FIG. 3 is an overall system diagram showing a vehicle equipped with a device (an example of a braking / driving force control device) and an active suspension control device (an example of a wheel load distribution control device). FIG. 3 shows a specific example of a front and rear wheel steering angle control system. FIG. 4, FIG. 4 is a diagram showing a specific example of the front and rear wheel driving force distribution control system, FIG. 5 is a diagram showing a specific example of the active suspension control system, and FIG. FIG. 7 is a flow chart showing the flow of the control sensitivity setting processing operation in the integrated controller of the first embodiment.
The figure is a characteristic map of the auxiliary steering angle control sensitivity and the wheel load distribution control sensitivity with respect to the value of (X _G ² + Y _G ² ), FIG. 9 is a control sensitivity ratio characteristic graph, and FIG. 6 is a flowchart illustrating a flow of a control sensitivity setting process operation in the controller. a: auxiliary steering angle control device b: wheel load distribution control device c: longitudinal acceleration detecting means d lateral acceleration detecting means e: total control sensitivity setting means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI B62D 131: 00 (58) Field surveyed (Int.Cl. ⁶ , DB name) B62D 6/00

Claims (2)

(57) [Claims] An auxiliary steering angle control device for controlling a steering angle of at least one of a front wheel and a rear wheel during front wheel steering; a wheel load distribution control device for controlling distribution of a load movement amount of each wheel; define a lateral acceleration detecting means for detecting a lateral acceleration, a comparison constant when representing the auxiliary steering angle target value proportional constant and the basic control and the steering angle multiplied by the formula and the auxiliary steering angle control sensitivity alpha _S, wheel load when the proportional constant when representing the distribution target value obtained by multiplying a proportional constant and basic wheel load distribution formula defined as wheel load distribution control sensitivity alpha _R, as the value of the lateral acceleration detection value is larger auxiliary steering angle control sensitivity And a total control sensitivity setting means for setting the auxiliary steering angle control sensitivity and the wheel load distribution control sensitivity so as to relatively increase the wheel load distribution control sensitivity. Integrated control system for wheel load distribution. An auxiliary steering angle control device for controlling the steering angle of at least one of a front wheel and a rear wheel during front wheel steering; a wheel load distribution control device for controlling distribution of a load moving amount of each wheel; Longitudinal acceleration detecting means for detecting longitudinal acceleration, lateral acceleration detecting means for detecting lateral acceleration acting on the vehicle, and a proportional constant when the auxiliary steering target value is represented by a formula obtained by multiplying a proportional constant by a basic control steering angle. was defined as the auxiliary steering angle control sensitivity alpha _S, when defining the proportionality constant in the case of representing the wheel load distribution target value by the formula obtained by multiplying a proportional constant and basic wheel load distribution between the wheel load distribution control sensitivity alpha _R, Calculates the sum of the square of the longitudinal acceleration detection value and the square of the lateral acceleration detection value, and increases the value of the ratio of the wheel load distribution control sensitivity to the auxiliary steering angle control sensitivity as the sum increases. Sensitivity and wheel load distribution control sensitivity And a total control sensitivity setting means for setting the auxiliary steering angle and the wheel load distribution.