EXPERIMENTAL INVESTIGATION OF MECHANICAL-HYDROSTATIC CONTINUOUSLY VARIABLE TRANSMISSION

In this paper, a mechanical-hydrostatic continuously variable transmission system (MHCVT) is proposed and experimentally investigated. The proposed system characterized by stepless speed regulation consists of a closed-loop hydraulic circuit and a rubber V-belt train. Firstly, the working principle of the MHCVT is described in detail. Next, the basic formulation including the speed ratio, torque, pressure, flow rate of the MHCVT is drawn and the dynamic equation of the system is then derived. Secondly, for the purpose of continuous speed adjustment, a proper control algorithm will be suggested. Due to the uncertain, unknown and nonlinear response in the MHCVT, it exists a potentially difficult problem to design a model-based controller. Hence, in order to overcome this issue, a fuzzy sliding mode controller (FSMC) is introduced for controlling the hydraulic system to change automatically the speed of the output at the certain range. Finally, an experimental apparatus of the MHCVT is established to verify the transmission effectiveness subjected to different operating conditions