Path control of a horizontal two-link robot driven by step motors.

Abstract

In this study, the mechanical system and the circular path control system of a horizontal two-link robot are constructed by utilizing step motors and harmonic drive gears. The effects of the excitation method of the step motors and the shape of the velocity pattern of the circular path control system on the dynamic characteristics are investigated. In the circular path control system, the control pulse generation algorithm to the step motors is constructed by use of inverse kinematics. From the experimental results, it is seen that the circular path control can be achieved with a comparatively high accuracy. Then, it is advisable for stable and fast circular path control without the failure phenomenon of the step motors, to utilize the two-phase excitation method of the step motors and the trapezoidal velocity pattern of the circular path control.