Challenges and Opportunities.pdf

2005 American Control Conference
June 8-10, 2005. Portland, OR, USA
Challenges and Opportunities
in Automotive Transmission Control
Zongxuan Sun and Kumar Hebbale
Research and Development Center
General Motors Corporation
Warren, MI 48090
Abstract: Automotive transmission is a key element many of the new automatic transmissions (AT),
in the powertrain that connects the power source to clutch-to-clutch shift is adopted to reduce the cost and
the wheels of a vehicle. To improve fuel economy, improve packaging. This involves electronic control of
reduce emission and enhance driving performance, both the ing and offgoing clutches and the
many new technologies have been introduced in the timing and coordination between them. In addition to
transmission area in recent years. This paper first eliminating the shift valves, accumulators, etc., clutch-
reviews different types of automotive transmissions to-clutch control eliminates the coasting clutches and
and explains their unique control characteristics. We freewheelers, greatly simplifying the transmission
then address the challenges facing automotive mechanical content. The absence of these devices
transmission control from three aspects: calibration, makes the robust control of clutch-to-clutch shifts a
shift scheduling, and sensing, actuation and challenge.
electronics.