System for controlling the running state of a vehicle in accordance with a steering angle

• US 5,379,222 A
• Filed: 11/19/1991
• Issued: 01/03/1995
• Est. Priority Date: 11/30/1990
• Status: Expired due to Fees

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Anan, Yoshiaki, Yamashita, Tetsuhiro, Nagaoka, Mitsuru
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): PARK, COLLIN
• Application Number:
  US07/794,518
• Time in Patent Office: 1,141 Days
• Field of Search: 364/424.05, 364/426.01, 364/426.02, 364/426.03, 180/197, 180/142, 180/141, 280/707, 303/93, 303/94, 303/95, 303/96, 303/102, 303/103
• US Class Current: 701/91
• CPC Class Codes: B60G 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/208 of wheel rotation
• CPC Class Codes: B60G 2400/33 Throttle position
• CPC Class Codes: B60G 2400/41 Steering angle
• CPC Class Codes: B60G 2400/50 Pressure
• CPC Class Codes: B60G 2400/822 Road friction coefficient determination affecting wheel traction
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60G 2600/02 Retarders, delaying means, dead zones, threshold values, cut-off frequency, timer interruption
• CPC Class Codes: B60G 2800/18 Starting, accelerating
• CPC Class Codes: B60G 2800/21 Traction, slip, skid or slide control
• CPC Class Codes: B60G 2800/22 Braking, stopping
• CPC Class Codes: B60G 2800/90 System Controller type
• CPC Class Codes: B60G 2800/92 ABS - Brake Control
• CPC Class Codes: B60K 28/10 responsive to conditions relating to the vehicle
• CPC Class Codes: B60T 2201/16 Curve braking control, e.g. turn control within ABS control algorithm
• CPC Class Codes: B60T 2220/03 Driver counter-steering; Avoidance of conflicts with ESP control
• CPC Class Codes: B60T 2260/06 Active Suspension System
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60T 8/48 : connecting the brake actuator to an alternative or additional source of fluid pressure , e.g. traction control systems
• CPC Class Codes: B62D 6/00 : Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits means for initiating a change in direction B62D1/00; steering valves B62D5/06; combined with means for inclining the vehicle body or wheels on bends B62D9/00

Abstract

A running state control system having running state control means for controlling a running state of a vehicle, in which a control target quantity thereof is set different according to a steering angle, comprises steering angle detecting means for detecting the steering angle, and steering angle changing means for changing the steering angle detected by the steering angle detecting means into a filtered steering angle a decrease of which lags behind a decrease of an actual steering angle. Consequently, an abrupt change in a control condition can be prevented even during a slalom run and counter steering of a vehicle, thus enhancing a running stability of the vehicle.

Claims

1. A running state control system for a vehicle having running state control means for controlling running state of the vehicle, in which control target quantities for controlling the running state are set different according to a control steering angle, said running state control system comprising:

steering angle detecting means for detecting an actual steering angle;

steering angle changing means for changing the control steering angle from the actual steering angle detected by said steering angle detecting means to a filtered steering angle a decrease of which lags behind a decrease of the actual steering angle; and

steering angle decrease judging means for judging that the actual steering angle is decreasing when the absolute value of the present actual steering angle detecting by said steering angle detecting means is smaller than the previous output value of said steering angle changing means,

wherein said steering angle changing means changes the control steering angle from the actual steering angle to the filtered steering angle when said steering angle decrease judging means judges the decrease of the actual steering angle.

2. A running state control system defined in claim 1, wherein said steering angle changing means obtains the filtered angle based on a formula,

3. A running state control system defined in claim 1, wherein said running state control means serves as traction control means for controlling a driving wheel so that a spin quantity of said driving wheel with respect to a road surface reaches to a target quantity, and the target quantity is changed according to the control steering angle.

4. A running state control system defined in claim 3, wherein said traction control means is composed of:

engine control means for controlling an engine output so that the spin quantity of said driving wheel with respect to a road surface reaches to a first target quantity; and

brake control means for controlling a brake force to be applied to said driving wheel so that the spin quantity of said driving wheel with respect to a road surface reaches to a second target quantity,

the first and second target quantities being respectively set high during a straight run and set low during a turn of the vehicle according to the control steering angle.

5. A running state control system defined in claim 4, wherein the first and second target quantities are respectively set low as a vehicle speed is high and set low as a stepped quantity of an accelerator pedal is large.

6. A running state control system defined in claim 5, wherein the first and second target quantities are respectively set low as a friction coefficient of a road surface is small.

7. A running state control system defined in claim 1, wherein said running state control means serves as an automatic adjusting suspension for controlling each damping ratio of shock absorbers respectively provided at front right side, front left side, rear right side and rear left side of the vehicle, and a control target quantity of damping ratio is changed according to the control steering angle.

8. A running state control system defined in claim 7, wherein said automatic adjusting suspension controls each actuator, provided at each of said shock absorbers, for adjusting each damping ratio according to running conditions of the vehicle, and a control target quantity of each damping ratio is set high during a straight run and set low during a turn of the vehicle.