Design and Control of the Active Compliant End-Effector

The design, construction end control of a wide bandwidth, active end-effector which can be attached to the end-point of a commercial robot manipulator is presented here. Electronic compliancy (Impedance Control) (11) has been developed on this device. The end-effector behaves dynamically as a two-dimensional, Remote Center Compliance [RCC]. The compliancy in this active end-effector is developed electronically and can therefore be modulated by an on-line computer. The device is a planar, five-bar linkage which is driven by two direct drive, brush-less DC motors. A two-dimensional, piezoelectric force cell on the end-point of the device, two 12-bit encoders, and two tachometers on the motors form the measurement system for this device. The high structural stiffness and light weight of the material used in the system allows for a wide bandwidth Impedance Control.