Under-actuated robot systems: dynamic interaction and adaptive control

Abstract

An under-actuated robot manipulator is a serial mechanism, in which the number of joints is greater than the number of actuators. Making use of the dynamic interaction between the passive joints and actuated joints, the robot can provide desirable motion and forces dynamically. In comparison to a fully actuated robot, the under-actuated system will be more compact in size and lower in weight due to less actuators, and more efficient due to less energy consumption. In this paper, we deal with the following two problems: 1) the dynamic coupling of the system and the control problem of the system by using its dynamic coupling; and 2) when the dynamic parameters are uncertain/unknown in practice, and the kinematics relationship is thus not accurate, the feasible application of adaptive control scheme for this nonlinear system where the linear parameterization does not hold and linear structured adaptive control scheme is not valid, is considered.