Patent · US Expired

Four wheel steering system with speed-dependent phase reversal

US5224042A · kind A · utility

8Cited by
11References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 19, 1991
Grant dateJun 29, 1993
Priority date
Expiry dateFeb 19, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB62D7/159
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A four wheel steer control system which uses vehicle speed, front wheel position, and the rate of change of the front wheel position to develop the rear wheel steering command. The rear steering command is a combination of the steady state and transient rear wheel commands which are developed individually. The rear wheel steady state command is a function of vehicle speed and front wheel position. The rear wheel transient command is a function of the rate of change of the front wheel position and vehicle speed. Determining the rate of change of front wheel position is done by taking samples of the front wheel position over time and calculating the difference in position between consecutive samples. As the vehicle speed changes the number of differences which are used to calculate the rate of change varies, allowing for the constant tuning of the response time of the rear wheels, resulting in a vehicle which is optimized for response and stability over the entire range of vehicle speeds.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.