Abstract: A method of making a strain wave includes the steps of a) providing a circular spline, a flexspline meshed with the circular spline, and an initial wave generator having an initial outer profile of a standard ellipse with a perimeter S0, and b) producing a modified wave generator rotatably fitted within the flexspline and having a modified outer profile with a perimeter S. A difference ES between the perimeter S of the modified outer profile and the perimeter S0 of the initial outer profile satisfies the equation ES=S?S0=0.1 m to 0.8 m, wherein m is the modulus of the flexspline. Through a special parameter design of the modified wave generator, the meshing ratio between the circular spline and the flexspline is increased, thereby improving the transmission accuracy and reducing the average load.

Abstract: A method of making a strain wave includes the steps of a) providing a circular spline, a flexspline meshed with the circular spline, and an initial wave generator having an initial outer profile of a standard ellipse with a perimeter S0, and b) producing a modified wave generator rotatably fitted within the flexspline and having a modified outer profile with a perimeter S. A difference ES between the perimeter S of the modified outer profile and the perimeter S0 of the initial outer profile satisfies the equation ES=S?S0=0.1 m to 0.8 m, wherein m is the modulus of the flexspline. Through a special parameter design of the modified wave generator, the meshing ratio between the circular spline and the flexspline is increased, thereby improving the transmission accuracy and reducing the average load.

Abstract: A harmonic drive includes a rigid internal gear, a flexible external gear meshed with the rigid internal gear, and a wave generator abutted against the flexible external gear. Through a special parameter setting to design the outer peripheral edge of the wave generator in a surface of variable curvature, the contact area between the wave generator and the flexible external gear is increased to improve fretting wear, thereby enhancing transmission accuracy and reducing hysteresis error.

Abstract: A harmonic drive includes a rigid internal gear, a flexible external gear meshed with the rigid internal gear, and a wave generator abutted against the flexible external gear. Through a special parameter setting to design the outer peripheral edge of the wave generator in a surface of variable curvature, the contact area between the wave generator and the flexible external gear is increased to improve fretting wear, thereby enhancing transmission accuracy and reducing hysteresis error.

Abstract: A harmonic drive includes a circular spline, a flexspline meshed with the circular spline, and a wave generator abutted against the flexspline. Through a special parameter design to correct the perimeter curve of the wave generator, the meshing efficiency between the circular spline and the flexspline is increased, thereby improving the transmission accuracy and reducing the average load.