A concurrent design of input shaping technique and a robust control for high-speed/high-precision control of a chip mounter

Input Shaping Technique (IST) and Time Delay Control (TDC), a robust feedback control law, were combined to achieve fast and precise point-to-point motion of a chip mounter. TDC was used as a feedback control to overcome disturbances and parameter variations, an IST was used to suppress the residual vibration induced in the closed loop system. TDC was designed first for the machine, and a discrete version of IST was designed on the basis of the closed-loop dynamics. In the design of TDC, a better set of gains was available thanks to the use of IST than TDC alone; in the design of IST, too, a better design was possible than IST alone. As the result of the concurrent design and synergy of the two methods, point-to-point motion could be achieved with no overshoot, the settling time of about 0.05 s and few steady-state errors to position commands of 1.5 turn. This result is far better than a conventional PID control or TDC alone could achieve, thereby showing the effectiveness of the concurrent design. (C) 2001 Published by Elsevier Science Ltd.