Control of Mechanical Systems with Flexibility

Rigid-link flexible-joint mechanical systems arise from applications where either motor shaft flexibility or gearbox flexibility, due to harmonic drives, appears. A classical example of such mechanical systems is robot manipulators. Position regulation in rigid-link flexible-joint robot manipulators is an old control problem which motivated an important research activity during the 1990 and 2000 decades. Although interest in this topic has diminished since then, the design of a PID controller driven by the link position errors ensuring global stability results still remains an open problem.