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In this study, a co-operative regenerative braking control algorithm was developed for an electric vehicle (EV) equipped with an electronic wedge brake (EWB) for its front wheels and an electronic mechanical brake (EMB) for its rear wheels. The co-operative regenerative braking control algorithm was designed considering the road friction characteristic to increase the recuperation energy while avoiding wheel lock. A powertrain model of an EV composed of a motor, and batteries and a MATLAB model of the control algorithm were also developed. They were linked to the CarSim model of the vehicle under study to develop an EV simulator. The EMB and EWB were modeled with an actuator, screw, and wedge to develop an EMB and EWB simulator. A co-simulator for an EV equipped with an EWB for the front wheels and an EMB for the rear wheels was fabricated, composed of the EV and the EMB and EWB simulator.

A fuzzy logic ratio control algorithm for a metal belt CVT is suggested considering the on-off characteristics of the ratio control valve and the nonlinear characteristics of the CVT shift dynamics. In the fuzzy logic, variable computation time for the error of the ratio and the rate of the error is suggested depending on the velocity of the rate of the CVT ratio. Experimental results show that a desired speed ratio can be achieved at a steady state by the fuzzy logic in spite of the fluctuating primary pressure. In addition, it was found that a faster response and better robustness can be obtained when compared with those of the PID control. It is expected that the ratio control algorithm suggested in this study can be implemented in a prototype CVT.