Control method for suspension

• US 20020116104A1
• Filed: 12/07/2001
• Published: 08/22/2002
• Est. Priority Date: 12/27/2000
• Status: Active Grant

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Kawashima, Mitsunori, Suto, Shinji, Watanabe, Kazuhisa, Kitazawa, Hirokazu
• Granted Patent: US 6,671,596 B2
• Time in Patent Office: Days
• US Class Current: 701/37
• CPC Class Codes: B60G 7/006 Attaching arms to sprung or unsprung part of vehicle, characterised by comprising attachment means controlled by an external actuator, e.g. a fluid or electrical motor B62D7/146 takes precedence

Abstract

A suspension control method for controlling a suspension which includes respective actuators for left and right wheels of a vehicle, and which can apply forces in the upwards and downwards direction to the left and right vehicle wheels via these actuators. While the vehicle is being driven in a straight line, control is performed by giving priority to ride comfort; and, while the vehicle is being driven around a curve, control is performed by giving priority to roll suppression.

Claims

1. A suspension control method for controlling a suspension which comprises respective actuators for left and right wheels of a vehicle, and which can apply forces in the upwards and downwards direction to said left and right vehicle wheels via these actuators, wherein:

while said vehicle is being driven in a straight line, control is performed by giving priority to ride comfort; and

while said vehicle is being driven around a curve, control is performed by giving priority to roll suppression.

2. A suspension control method according to claim 1, wherein, if the acceleration in the forwards and rearwards direction of said vehicle is greater than a predetermined value, control is performed by giving priority to pitching suppression, even while said vehicle is being driven in a straight line.

3. A suspension control method according to claim 1, wherein the forces generated by said actuators are varied according to the speed of said vehicle.

4. A suspension control method according to claim 1, wherein the acceleration of said vehicle in the upwards and downwards direction is detected, and, if the value of this upwards and downwards acceleration falls outside a predetermined range of values, and has continued to be outside said predetermined value range for longer than a predetermined time period, then control is performed to suppress vibration of said vehicle based upon the value of said upwards and downwards acceleration which is detected.

5. A suspension control method according to claim 1, wherein the acceleration of said vehicle in the upwards and downwards direction is detected, and, if the value of this upwards and downwards acceleration falls within a predetermined range of values, and has continued to be within said predetermined value range for longer than a predetermined time period, then control is not performed to suppress vibration of said vehicle based upon the value of said upwards and downwards acceleration which is detected.

6. A control method for an electromagnetic actuator, comprising:

a step of, when supplying electrical current to said electromagnetic actuator to generate a desired output, calculating a first duty ratio for said electrical current to be supplied to said electromagnetic actuator corresponding to a target electrical current value for said electrical current;

a step of calculating a second duty ratio for said electrical current to converge the actual electrical current value which flows through said electromagnetic actuator to said target electrical current value by proportional integral and differential control; and

a step of supplying electrical current to said electromagnetic actuator according to a third duty ratio which is obtained by adding together said first duty ratio and said second duty ratio.

7. A control device for an electromagnetic actuator, comprising:

a target electrical current value calculation device which, when supplying electrical current from a power source device to said electromagnetic actuator to generate a desired output, calculates a target electrical current value for said electrical current;

a first duty ratio calculation device which calculates a first duty ratio for said electrical current to be supplied from said power source device to said electromagnetic actuator corresponding to said target electrical current value;

an electrical current detection device which detects the actual electrical current which flows through said electromagnetic actuator and obtains an actual electrical current value;

a second duty ratio calculating device which calculates a second duty ratio for said electrical current to converge said actual electrical current value to said target electrical current value by proportional integral and differential control; and

a current control device which supplies electrical current from said power source device to said electromagnetic actuator according to a third duty ratio which is obtained by adding together said first duty ratio and said second duty ratio.

8. An actuator control method which can generate force to suppress rolling of a vehicle body, wherein a difference between amounts of movement of left and right wheels of said vehicle in the upwards and downwards direction is detected, and rate of change of steering angle is detected, and actuators are controlled based upon said vehicle wheel movement amount difference and upon said rate of change of steering angle.

9. A suspension control method according to claim 8, wherein a stabilizer is provided which mechanically links together said left and right vehicle wheels, and which generates torque according to the difference between the movement amounts of said left and right vehicle wheels in the upwards and downwards direction with respect to said vehicle body;

and wherein deficiency of force to suppress rolling of said vehicle body is, as required, supplemented by said actuators.

11. A suspension control method according to claim 8, wherein:

when the roll direction of said vehicle and the steering speed direction are the same, control is performed based upon said vehicle wheel movement amount difference with respect to said vehicle body, and upon said rate of change of steering angle;

when the roll direction of said vehicle and the steering speed direction are not the same, control is performed based upon said vehicle wheel movement amount difference with respect to said vehicle body; and

in the central state when the amount of rolling of said vehicle body is small, without any dependence upon whether or not the roll direction of said vehicle and the steering speed direction are the same, control is performed based upon said vehicle wheel movement amount difference with respect to said vehicle body, and upon said rate of change of steering angle.

13. A suspension control method according to claim 11, wherein, when determining upon said central state, the decision is made utilizing hysteresis.

14. A suspension control method according to claim 12, wherein, when determining upon said central state, the decision is made utilizing hysteresis.

10. An actuator control method which can generate force to suppress rolling of a vehicle body, wherein sidewise acceleration of said vehicle body is detected, and said actuator is controlled according to said sidewise acceleration and upon rate of change of steering angle.

12. A suspension control method according to claim 10, wherein

when the roll direction of said vehicle and the steering speed direction are the same, control is performed based upon said sidewise acceleration and upon said rate of change of steering angle;

and

when the roll direction of said vehicle and the steering speed direction are not the same, control is performed based upon said sidewise acceleration, while, in the central state when the amount of rolling of said vehicle body is small, without any dependence upon whether or not the roll direction of said vehicle and the steering direction are the same, control is performed based upon the sidewise acceleration of said vehicle wheels with respect to said vehicle body, and upon said rate of change of steering angle.