Electric control apparatus for control of the running characteristic of a wheeled vehicle

• US 5,204,815 A
• Filed: 02/20/1991
• Issued: 04/20/1993
• Est. Priority Date: 02/20/1990
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha 1 Toyota-Cho Toyota-Shi Aichi-Ken Japan
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yamamoto, Masaki
• Primary Examiner(s): Black, Thomas G.
• Application Number:
  US07/657,763
• Time in Patent Office: 790 Days
• Field of Search: 364/426.03, 364/424.05, 364/426.01, 180/197, 280/707
• US Class Current: 701/38
• 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 2800/0122 Roll rigidity ratio; Warping
• CPC Class Codes: B60G 2800/18 Starting, accelerating
• CPC Class Codes: B60G 2800/214 by varying the load distribution
• CPC Class Codes: B60G 2800/22 Braking, stopping
• CPC Class Codes: B60R 16/023 for transmission of signals between vehicle parts or subsystems
• CPC Class Codes: B62D 7/159 characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition

Abstract

An apparatus for estimating a slip angle in a wheeled vehicle having a set of front road wheels and a set of rear road wheels, including the same kind of wheel speed sensors arranged to detect each rotation speed of the road wheels for producing wheel speed signals respectively indicative of the detected rotation speeds of the road wheels, and a microcomputer responsive to the wheel speed signals from the sensors for calculating a first difference in speed between the front and rear road wheels and a second difference in speed between the left and right road wheels and for calculating a ratio of the first difference in speed relative to the second difference in speed for estimating the calculated ratio as a slip angle of the vehicle.

Claims

1. An electric control apparatus for controlling a running characteristic of a wheeled vehicle having a set of front road wheels and a set of rear road wheels, comprising:

wheel speed detecting means for detecting each rotation speed of the front and rear road wheels for producing wheel speed signals respectively indicative of the detected rotation speeds of the road wheels,

first means, responsive to said wheel speed signals, for detecting a first difference in speed between the front and rear road wheels and a second difference in speed between the left and right road wheels;

second means for calculating a ratio of the first difference in speed relative to the second difference in speed and for estimating a slip angle of the vehicle based on the calculated ratio; and

third means for controlling the running characteristic of the vehicle in accordance with the estimated slip angle.

2. An electric control apparatus as claimed in claim 1, wherein said third means comprises an electrically operated suspension mechanism for controlling a distribution ratio of roll stiffness at the front and rear road wheels in accordance with the estimated slip angle of the vehicle.

3. An electric control apparatus as claimed in claim 1, wherein said first means includes means for calculating a first difference in speed between the front and rear road wheels at one side of the vehicle and a second difference in speed between the left and right road wheels at one of the front or rear of the vehicle.

4. An electric control apparatus as claimed in claim 1, further comprising means for calculating a yaw-rate of the vehicle based on the calculated second difference in speed between the left and right road wheels and means for calculating an average value of said each detected rotation speed of the road wheels, for estimating a travel speed of the vehicle based on the calculated average value, and wherein said third means comprises an electrically operated rear-wheel steering mechanism for controlling a steering angle of the rear road wheels in accordance with the estimated travel speed, the estimated slip angle and the calculated yaw-rate of the vehicle.