Experimental Study of Electro-Mechanical Dual Acting Pulley Continuously Variable Transmission Ratio Calibration

This paper presents an experimental study of Electro-mechanical Dual Acting Pulley (EMDAP) Continuously Variable Transmission (CVT) ratio calibration. When there is no slip between belt and pulley sheaves, the CVT ratio will be the same as the geometrical ratio of secondary to primary pulley radii as well as the primary to secondary speed ratio. In EMDAP CVT system, both primary and secondary DC motors are used to control the primary and secondary axial pulley positions to vary the primary and secondary pulley radii. In this case, the pulley radii can be measured indirectly using axial pulley position sensors. Calibration process is carried out by manually adjusting the geometrical ratio of secondary to primary radii based on measurements of primary and secondary pulley positions and validated with the primary to secondary speed ratio determined from primary (input) and secondary (output) shaft speed measurements for the CVT ratio range of 0.7 to 2.0. The calibration results are recorded and used as reference data for future EMDAP CVT calibration and ratio control developments.