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An electronic throttle is a low-power dc servo drive which positions the throttle plate. Its application in modern automotive engines leads to improvements in vehicle drivability, fuel economy, and emissions. Transmission friction and the return spring limp-home nonlinearity significantly affect the electronic throttle performance. The influence of these(More)
The paper presents a conjugate gradient-based numerical algorithm for optimal control of nonlinear multivariable systems with control and state vectors constraints. The algorithm has a backward-in-time recurrent structure similar to the backpropagation-through-time (BPTT) algorithm. The emphasis is on implementation and testing of various conjugate gradient(More)
The steady-state and transient accuracy of magnetorheological fluid (MRF) clutch torque control is affected by the magnetic hysteresis and eddy current lag. The paper presents a nonlinear analytical model of the MRF clutch electromagnetic circuit dynamics. The model includes two state variables describing the combined solenoid and eddy current dynamics, and(More)
A dynamic tire friction model based on the LuGre friction model has been developed recently. The model includes the longitudinal and lateral forces, as well as the self aligning torque. It has originally been derived in distibuted form, and then transformed to simpler lumped form with only three internal states. The lumped model has been based on uniform(More)
Control strategy for a series-parallel hybrid electric vehicle powertain aimed at operating the engine in its optimal fuel efficiency operating region is proposed in the paper. An instantaneous optimization algorithm based on the equivalent consumption minimization strategy (ECMS) is used in order to improve the hybrid vehicle fuel efficiency, and it is(More)
The paper presents a novel concept of switching traction control (or ABS) strategy which does not rely on wheel slip information. The core of the strategy includes a driven wheel speed control loop and a reference vehicle model in the wheel speed target path. The reference model is fed by a bidirectional sawtooth-like tire force input signal, in order to(More)
A back propagation through time-like conjugate gradient-based algorithm is used for off-line optimization of a series-parallel hybrid power train control variables over standardized certification driving cycles. The aim is to minimize the fuel consumption subject to battery state-of-charge constraints. The optimization is carried out using a simplified(More)
This paper presents an adaptive Kalman filter for estimation of longitudinal tire static curve gradient, based on the driven wheel speed measurement. The static curve gradient estimator is used along with a model-based traction control (or ABS) strategy that does not require wheel slip information. More specifically, the estimator is used to establish a(More)