Vehicle with a variable rear toe angle

• US 8,068,955 B2
• Filed: 01/07/2009
• Issued: 11/29/2011
• Est. Priority Date: 01/08/2008
• Status: Expired due to Fees

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Yanagi, Takashi
• Primary Examiner(s): Jayne; Darnell
• Assistant Examiner(s): RODDEN, JOSHUA E
• Application Number:
  US12/349,852
• Publication Number:
  US 20090177348A1
• Time in Patent Office: 1,056 Days
• Field of Search: 701/29, 701/34, 701/41, 701/43, 180/404, 180/411, 280/86.758
• US Class Current: 701/43
• CPC Class Codes: B62D 7/148 provided with safety devices

Abstract

In a vehicle provided with a rear wheel toe angle varying device for individually varying toe angles of rear wheels, upon detection of a failure to steer one of the rear wheels, the rear wheel of a healthy side is steered to a zero angle. Whereby, when a straight travel determining unit determines that the vehicle is traveling straight, a toe angle estimating unit estimates a steering angle of the rear wheel which has failed to steer based upon the steering angle of the front wheels of the vehicle as determined by a steering angle sensor.

Claims

1. A vehicle provided with a rear wheel toe angle varying device for individually varying toe angles of rear wheels, the rear wheel toe angle varying device comprising:

a pair of drive units for steering the rear wheels;

at least one sensor for detecting a dynamic state of the vehicle;

a control unit for controlling the drive units according to an output of the dynamic state of the vehicle from the sensor; and

a monitoring unit for detecting a failure to steer a rear wheel as controlled by the control unit;

wherein the control unit is configured such that, upon detection of a failure to steer a rear wheel, the rear wheel of an opposite, healthy side is steered to a zero angle;

a steering angle sensor for detecting a steering angle of front wheels of the vehicle, a straight travel determining unit for determining that the vehicle is traveling straight ahead, and a toe angle estimating unit that, upon occurrence of a failure of said control unit to steer one of the rear wheels, and the rear wheel of the opposite, healthy side being steered to a zero angle by said control unit, estimates a steering angle of the rear wheel of a faulty side from the steering angle of the front wheels when the straight travel determining unit determines the vehicle is traveling straight ahead.

2. The vehicle provided with a rear wheel toe angle varying device according to claim 1, wherein the monitoring unit for detecting a failure to steer each rear wheel is configured to detect a fault in a stroke sensor that detects an actual steered angle of the corresponding rear wheel.

3. The vehicle provided with a rear wheel toe angle varying device according to claim 1, wherein the monitoring unit for detecting a failure to steer each rear wheel is configured to detect a fault in a power actuator for steering each rear wheel.

4. The vehicle provided with a rear wheel toe angle varying device according to claim 1, wherein the monitoring unit for detecting a failure to steer each rear wheel is configured to detect a fault in a part of the control unit responsible for steering each rear wheel.

5. The vehicle provided with a rear wheel toe angle varying device according to claim 1, wherein the toe angle estimating unit estimates the steering angle of the rear wheel of the faulty side to be one half of the steering angle of the front wheels.