Co-Operating Clutch and Engine Control for Servoactuated Shifting Through Fuzzy Supervisor

The paper discusses a fuzzy supervisor for ensuring co-operation between clutch and engine control reference values during standing starts and gear shifts in a vehicle equipped with a servoactuated transmission. A mathematical model of the powertrain was developed to identify the optimal control strategy for different clutch friction characteristics and operating conditions.

The powertrain is modeled as a six d.o.f. dynamic system, consisting of the engine and flywheel assembly, clutch disk, mainshaft and countershaft, transmission shaft with differential and hub, front wheels, tires and car body with rear wheels. The engine is described by its experimental mechanical characteristic. The model considers lumped parameters, and springiness of the shafts is neglected.

A large number of simulations was carried out in order to identify control strategies which minimize dissipated power and judder and prevent engine stalling during standing starts. Simulation results are then used to define a fuzzy supervisor knowledge base.