James William Loch McCallum

Hydraulic clutch modeling for automotive control

A low-order dynamic model of a clutch for hydraulic control in an automatic transmission is developed by separating dynamics of the shift into four regions based on clutch piston position. The first three regions of the shift are captured by a physics-based model and the fourth region is represented by a system identification model. These models are determined using nominal values and validated against nominal and off-nominal experimental data. The model provides two lumped flow parameters to be used for tuning to the desired hydraulic clutch system.

Iterative model and trajectory refinement for launch optimization of automotive powertrains

Abstract A recently proposed iterative model and trajectory refinement (IMTR) approach is applied to launch control of an automotive powertrain with a turbocharged gasoline engine and a dual-clutch transmission. The optimal clutch torque trajectory is determined by a piecewise linear in time function that minimizes a cost function while meeting multiple constraints on vehicle acceleration and engine speed. A high-fidelity model of the powertrain and a simplified physics-based model are used iteratively to refine solutions. The iterative method converges on a solution that meets target performance metrics with efficient execution time.