Input preshaping control of the safe arm with MR-based passive compliant joints

In this paper, design and control of a safe arm with passive compliant joints (PCJ) are presented. A new manipulator with passive compliance property has been developed at KIST. Strategy for the joint control method is implemented. Because the PCJ is a flexible joint, unwanted vibration is occurred during the joint motion. To reduce this vibration, we use the input-preshaping method which is motivated by the input shaping technique (IST) based on impulse response. The control method for a time-varying system like the safe arm is described in detail. The result of simulations and experiments proves that a fast motion of the safe arm without residual vibration can be achieved.