Design and Implementation of a Vision-based Treadmill System Driven by a Permanent Magnet Synchronous Motor

This study focuses on the development of a vision- based treadmill system that is actuated by a permanent magnet synchronous motor (PMSM). The PMSM employed in our design is free of commutation spikes and maintenance, so that it can replace the DC motor that is often adopted in the conventional treadmill system. Moreover, to achieve a smooth low speed operation, the sinusoidal Back EMF and the SPWM are exploited to achieve sinusoidal commutation for the PMSM. In addition, two kinds of running modes - active and passive, are developed in this paper. In the active running mode, the running speed of the treadmill is set up by the user through a human-machine interface, while in the passive running mode the user can determine the magnitude of the retard force and running speed by himself/herself. To build a user friendly environment, a virtual touch panel is projected onto a screen/wall through a projector, and a vision-based motion detection algorithm is used to determine which button of the virtual touch panel is pressed by the user. In this way, without actually touching the panel, the user can operate the treadmill while running/jogging, so that greatly enhancing the convenience.