Fuzzy logic speed estimator to drive a four electric wheels truck

This paper introduces a fuzzy logic application to estimate the speed of a vehicle with four electric drives wheels. The vehicle speed (which is different from wheels speed characterized by slip in the driving mode) is an essential input for a traction control system, designed to assure the dynamics and stability of vehicle which have not the gearbox and mechanical differential. The four electric motors of the wheels give the possibility to measure the torque and the speed of each wheel. In order to estimate the vehicle speed, proposed fuzzy estimator use like reference the measured wheels speeds and torque. The integration of the torque in this estimator is realized by an original approach proposed by authors. The proposed traction structure control, the design of fuzzy speed estimator and several results, which show the potential of such an estimator, are presented.