Adaptive Nonlinear Observer for Electropneumatic Clutch Actuator With Position Sensor

This brief proposes an adaptive nonlinear observer for an electropneumatic clutch actuator. Estimates of piston velocity, chamber pressures, and dynamic friction state are made based on piston position measurement only. Parameter estimations of the clutch load characteristics and friction coefficients are treated through adaptation, and the persistence of excitation conditions for convergence of the estimation errors are derived. The performance of the adaptive observer is evaluated and is compared to experimental measurements obtained in a test truck.