Stephen J Colby

US Patent:

61820024, Jan 30, 2001

Filed:

Oct 26, 1998

Appl. No.:

9/178791

Inventors:

Paul Alan Bauerle - Fenton MI
Stephen E. Colby - Grand Ledge MI

Assignee:

General Motors Corporation - Detroit MI

International Classification:

G06F 700
B60T 712

US Classification:

701 82

Abstract:

An improved traction control system in which a wheel spin condition is detected based on measured vehicle acceleration instead of measured wheel speeds. An electronic controller detects a wheel spin condition by computing the acceleration of the vehicle drive shaft and comparing the computed acceleration to an acceleration threshold stored as function of vehicle speed and wheel torque. If the computed acceleration exceeds the threshold for more than a predetermined time, the engine torque is reduced in relation to the amount by which the computed acceleration exceeds the threshold. When the computed acceleration falls below the threshold, the torque reduction is gradually removed. The wheel torque, vehicle speed and drive shaft acceleration are easily determined and filtered, and the incremental cost of the traction control function is primarily related to the memory requirements to accommodate the acceleration threshold look-up table. The control may be mechanized in a vehicle having electronic throttle control, and the desired torque reduction in such a mechanization may be achieved with one or more of throttle area control, spark timing control and fuel cutoff control.