Electric power steering apparatus for vehicle
US8594892B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2009 |
| Grant date | Nov 26, 2013 |
| Priority date | — |
| Expiry date | Jan 4, 2030 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/0463
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A steering angle estimation section calculates a front-wheel-side estimative steering angle and a rear-wheel-side estimative steering angle through use of wheel speeds of respective wheels, and averages these steering angles to thereby obtain an accurate estimative steering angle. It also calculates an estimative steering angle difference between the steering angles. An axial force estimation section calculates a base axial force through use of the estimative steering angle and a vehicle speed, and calculates a correction axial force which applies an axial force difference (hysteresis) to the base axial force in accordance with a turning or returning operation by a driver. The axial force estimation section adds the base axial force and the correction axial force together to thereby calculate an accurate estimative axial force. An assist computation section compares a target steering torque, which changes with the vehicle speed, and the accurate estimative axial force, and subtracts the target steering torque from the estimative axial force, to thereby calculate an assist torque.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.