A method of full closed loop control system design for end effector's feed shaft was presented in order to ensure the countersink depth of robot drilling caused by the deformation and vibration of the aircraft's panels. The displacement of end effector's pressure foot was added to countersink depth as real-time compensation. A lowpass filter was introduced to restrain the interference of high frequency vibration to feed shaft's positioning accuracy according to the vibration frequency characteristics of the pressure foot during the drilling process. Its cutoff frequency was determined by the countersink depth accuracy of the aircraft's panels, and thereby the countersink depth was ensured and the high hole quality was achieved. Drilling with hole diameter 5.8 mm and 9.8 mm on arc and flat aluminum alloy workpiece respectively, the hole quality turned out to be very accurate, with the countersink depth variation at 0.02 mm in the worst case and the surface roughness reaching 0.8 μm.
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