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. 19, 2016
Filed:
Jul. 23, 2014
GM Global Technology Operations Llc, Detroit, MI (US);
Steven P. Moorman, Dexter, MI (US);
Brandon Fell, Milford, MI (US);
Mateusz Nowak, Dearborn, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A vehicle or other system includes hydraulic fluid, an actuatable device such as a clutch that includes a linear actuator, e.g., a clutch piston. The linear actuator is moveable via a pressure from the fluid to actuate the actuatable device. A position sensor measures and outputs a position of the linear actuator as a position signal. A controller is programmed to generate increasing and decreasing position-to-pressure (PTP) curves via measurement of the position, at a predetermined time, in response to a series of respectively increasing and decreasing pressure step commands. The controller adjusts the PTP curves using a calibrated set of offsets, locates a PTP point in a hysteresis range between the adjusted PTP curves, and controls the device using the PTP point. The offsets may include a temperature of the fluid, velocity of the linear actuator, and/or an engine speed.