Motion control system for vehicle

Abstract

In a motion control system for a vehicle having four wheels including at least two driving wheels which is driven by a driving power source, first rolling liability judging means (step 112) judges whether or not the rolling liability detected by rolling liability detecting means (step 102, a lateral acceleration sensor 39) for detecting the rolling liability of the vehicle is equal to or greater than a first predetermined rolling liability, and rolling suppression control means (steps 116, 124 to 129) suppresses the rolling liability of the vehicle by increasing the driving force of any of the driving wheels when the first rolling liability judging means judges that the rolling liability detected by the rolling liability detecting means is equal to or greater than the first predetermined rolling liability.

Description

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The foregoing and other objects and many of the attendant advantages of the present invention may readily be appreciated as the same becomes better understood by reference to the preferred embodiment of the present invention when considered in connection with the accompanying drawings, wherein like reference numerals designate the same or corresponding parts throughout several views, and in which:

FIG. 1 is a schematic view showing one embodiment of a vehicle to which a motion control system according to the present invention is applied;

FIG. 2 is a flow chart of a control program executed by a motion control ECU shown in FIG. 1;

FIG. 3 is a flow chart executed by the motion control ECU shown in FIG. 1 for the calculation of an early rolling suppression control amount;

FIG. 4 is a flow chart executed by the motion control ECU shown in FIG. 1 for the calculation of a yaw rate difference;

FIG. 5 is a map showing the relation between the lateral acceleration and the rolling angle (rolling liability);

FIG. 6 is a map showing the respective relations between the rolling liability and various control amounts including the increase control amount of the engine torque and the like;

FIG. 7 is a flow chart executed by the motion control ECU shown in FIG. 1 for the calculation of the early rolling suppression control amount in a modified form; and

FIG. 8 is a partial flow chart showing a processing which is executed in place of step 212 of the flow chart for the calculation of the early rolling suppression control amount shown in FIG. 3.

Claims

1. A motion control system for a vehicle having at least two driving wheels which are driven by a driving power source, comprising: rolling liability detecting means for detecting the rolling liability of the vehicle;first rolling liability judging means for judging whether or not the rolling liability detected by the rolling liability detecting means is equal to or greater than a first predetermined rolling liability; androlling suppression control means for suppressing the rolling liability of the vehicle by increasing the driving force of any of the driving wheels when the first rolling liability judging means judges that the rolling liability detected by the rolling liability detecting means is equal to or greater than the first predetermined rolling liability.

2. The motion control system as set forth in claim 1, wherein the rolling suppression control means changes the increase amount of the driving force of any of the driving wheels in dependence on the degree of the detected rolling liability.

3. The motion control system as set forth in claim 1, further comprising driving power source control means for controlling the driving power source of the vehicle, and wherein the rolling suppression control means increases the driving force of any of the driving wheels by increasing the driving power of the driving power source.

4. The motion control system as set forth in claim 1, further comprising front-rear driving power distribution control means for distributing the driving power from the driving power source of the vehicle to front and rear wheels, and wherein the rolling suppression control means increases the driving forces of the front wheels or the rear wheels by changing the distribution of the driving power to the front and rear wheels by the front-rear driving power distribution control means.

5. The motion control system as set forth in claim 1, further comprising brake force control means for controlling brake forces applied to the wheels of the vehicle, and wherein the rolling suppression control means increases the driving force of any of the driving wheels of the wheels by suppressing the spinning of any such driving wheels by the brake force control means.

6. The motion control system as set forth in claim 1, further comprising left-right driving power distribution control means for distributing the driving power from the driving power source of the vehicle to left and right driving wheels of the vehicle, and wherein the rolling suppression control means increases the driving force of the left driving wheel or the right driving wheel by changing the distribution of the driving power to the left and right driving wheels by the left-right driving power distribution control means.

7. The motion control system as set forth in claim 1, further comprising second rolling liability judging means for judging whether or not the rolling liability detected by the rolling liability detecting means is equal to or greater than a second predetermined rolling liability which is greater in the rolling liability than the first rolling liability; and wherein: the rolling suppression control means suppresses the rolling liability of the vehicle by increasing the driving force of any of the driving wheels when the first rolling liability judging means judges that the rolling liability detected by the rolling liability detecting means is equal to or greater than the first predetermined rolling liability and also suppress the rolling liability of the vehicle by decelerating the vehicle when the second rolling liability judging means judges that the rolling liability detected by the rolling liability detecting means is equal to or greater than the second predetermined rolling liability.

8. The motion control system as set forth in claim 1, wherein the rolling suppression control means suppresses the rolling liability of the vehicle by decelerating the vehicle when the change rate of the vehicle rolling liability is equal to or greater than a predetermined value.

9. The motion control system as set forth in claim 1, further comprising: wheel spinning judging means for judging whether or not any one wheel of the wheels of the vehicle is spinning;front-rear wheel speed difference judging means for judging whether or not a speed difference exists between front and rear wheels of the wheels; andleft-right wheel speed difference judging means for judging whether or not a speed difference exists between left and right wheels of the wheels, and wherein the rolling suppression control means:(a) increases the driving power of the driving power source of the vehicle when the wheel spinning judging means judges that none of the wheels is spinning;(b) increases the driving forces of the front wheels or the rear wheels by changing the distribution of the driving power to the front and rear wheels when the wheel spinning judging means judges that at least any one wheel of the wheels is spinning and when the front-rear wheel speed difference judging means judges that the speed difference exists between the front and rear wheels; and(c) increases the driving forces of the driving wheels by suppressing the spinning of at least any one driving wheel and/or by changing the distribution of the driving power to the left and right wheels when the wheel spinning judging means judges that at least any such one wheel of the wheels is spinning and when the left-right wheel speed difference judging means judges that the speed difference exists between the left and right wheels.

10. The motion control system as set forth in claim 1, further comprising: front-rear wheel speed difference judging means for judging whether or not a speed difference exists between front and rear wheels of the wheels;left-right wheel speed difference judging means for judging whether or not a speed difference exists between left and right wheels of the wheels; andvehicle speed reduction judging means for judging whether or not the vehicle speed is reduced, and wherein the rolling suppression control means:(d) increases the driving forces of the front wheels or the rear wheels by changing the distribution of the driving power from the driving power source of the vehicle to the front and rear wheels when the front-rear wheel speed difference judging means judges that the speed difference exists between front and rear wheels;(e) increases the driving force of any of the driving wheels by suppressing the spinning of any such driving wheel and/or by changing the distribution of the driving power to the left and right wheels when the left-right wheel speed difference judging means judges that the speed difference exists between the left and right wheels; and(f) increases the driving power of the driving power source when the vehicle speed reduction judging means judges that the vehicle speed is reduced.