Dynamics and control of a gravity-assisted underactuated robot arm for assembly operations inside an aircraft wing-box

We propose a novel concept for the actuation of a hyper-articulated robot arm for assembly operations inside an aircraft wing-box. Traditional electromechanical actuators powering individual joints are unsuitable for our purpose, because of limited space and large payload requirements. We propose an underactuated system which uses a single actuator at the base for the deployment of a multi d.o.f. serial linkage structure. Our proposed system exploits gravitational and gyroscopic torques in the system dynamics to rapidly deploy the system. There are no general techniques for the control of such underactuated systems. We develop and compare two approaches for determining the input required for a desired output trajectory and verify the results through simulation and experiments.