An open servo controlled robot system is suggested. Conventional 3-axis gantry machine and 5-axis manipulator was constructed.
1st axis, 2nd axis actuate separately (kinematics & dynamics were decoupled), and 3rd axis works like base axis in 6-axis articulated robot. In the lapping operation, most frequent motion is wiping.
For precise control system, position control was applied to the 1st, 3rd, 4th, and 5th axis motor, and feedforward torque control was used in 2nd axis motor.
From machining tests, lapping process with 5-axis robot manipulator shows the milling tool marks could be removed clearly while Ra is 0.5 ㎛ and Rz is 3.0 ㎛