High-speed trajectory control of a direct-drive manipulator

High-speed precision trimming of three-dimensional parts using laser-cutting industrial robots is addressed. A control system for direct-drive manipulators specially designed for high-speed trajectory control applications is developed. The concept of decoupled and invariant dynamics is discussed for a specific manipulator, and a simple procedure for system identification and control system design is presented. It is demonstrated that, through proper arm mechanism design, the control system can be greatly simplified and satisfactory control performance achieved. The arm mechanism design and control system are evaluated through simulations and experiments. Experimental tracking performance achieves a speed of 3 m/s and an acceleration of 3.8 g, with a joint mean tracking error of 0.0556 degrees .< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>