No-Backlash Control System by Two-Motor Drive (1st.Report, the Analyses and Experiments of Reference Response)

In this research, a new no backlash drive control system is proposed, and the basic principle and the analysis of the drive system, the control design method, the simulation, and the position control experimental results were described. The no backlash drive control system consists of common reduction gear, a motor, servo amplifier, and a control device, which drives one load, combining a pair of motors as for a plus direction motor and a minus one, and cancels a backlash. When driving the load to a plus direction, the torque of a plus direction motor is made to increase ,in which a plus direction motor and a minus one add equal offset torque to the load and, hold the load axis. At this time, a minus direction motor adds fixed torque in the inversion direction, forces a cog on the load axis, and cancels the backlash. It verified in the simulation that the responsibility could be improved by feeding back the average value of a plus direction motor and a minus one, as the position and velocity feedback signal, in consideration with the natural vibration of reverse phase being superposed. In the experiments, the backlash has been cancelled by this control system.