Abstract: A torque coordinating optimalcontrol strategy was developed using different driving intentions in
different shifting process phases for a six-speed Dry Dual-Clutch-Transmission (DDCT) of a self-developed car.
A simulation model was set up on the Matlab/Simulink software platform and then used to simulate the control
strategy for DDCT shifting process. The sub-divided phases included the quadratic optimal control adopted in
torque phase; the ignition parameters and fuel supply controlin inertia phase; the control factor mapping method,
which reflects driving intension, both in micro-slipping phase and in demanded torque switching phase. The
results show that shift jerks are within -2 m/s3 while the total frictional energy losses are within 2 kJ in shift
process. Therefore, this control strategy reflects driving intentions and meets the demand of shift quality.

Key words: automotive transmission, dry dual clutch transmission (DDCT), shifting process, torque coordinating, quadratic optimal control