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:
Jun. 06, 2017
Filed:
Jun. 09, 2015
GM Global Technology Operations Llc, Detroit, MI (US);
Ian Y. Hwa, West Bloomfield, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A method for characterizing a stick-slip or stiction condition in an electrically-assisted steering system includes transmitting a first steering control signal from a controller to a rotary actuator as a periodic steering conditioning signal, receiving a second steering control signal via a steering assist motor throughout the test to electrically assist steering, transmitting a third steering control signal to the rotary actuator to cause alternate rotation of the steering shaft to a target angle rate at constant acceleration/deceleration, and measuring a steering torque output from the rotary actuator. A control action is executed when a difference in local maximum and minimum peak amplitudes of the steering torque output exceeds a calibrated threshold difference indicative of stiction. A system includes a rotary actuator, the steering system, a torque transducer operable for measuring a steering torque imparted to the steering shaft by the rotary actuator, and the controller noted above.