The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1998
Filed:
May. 29, 1996
Kevin Michael McLaughlin, Troy, MI (US);
TRW Inc., Lyndhurst, OH (US);
Abstract
A control arrangement for an electric assist steering system having a variable reluctance motor (26) includes a motor position sensor (54) and an applied steering torque sensor (110). A controller determines a desired motor torque assist value in response to the applied steering torque. The controller modifies the desired torque assist value to linearize the gain relationship between the desired torque assist value and motor torque output. A plurality of look-up tables have a plurality of motor current values versus motor position values stored therein. The controller selects a first (T1) look-up table corresponding to a torque value less than the modified motor torque assist value and a second (T2) look-up table corresponding to a torque value greater than the modified motor torque assist value. A first motor current value (I1) and second motor current value (I2) are determined by interpolation. A final motor current value (ICMD) is determined by interpolating between the first and second determined motor current values. A motor control signal is provided in response to the determined final motor current value.