Abstract
The functions of the principal members of a flat-wheel harmonic drive are similar to the functions of a traditional harmonic drive, but the features of the flexible and the solid wheels are different. This paper reports on an analytical approximation method for tooth-load calculation based on backlash conditions of flat wheel harmonic drives. Deformation of teeth and the rotation of the flexible gear depending of loading torque are calculated. An experimental flat wheel harmonic drive is also introduced with measurement results.