Collision detection and suspend control of parallel- structured single-link flexible arms

This paper presents a method of collision detection and suspend control for parallel-structured single-link flexible arms. The exact dynamics of parallel-structured single-link flexible arm are described by quite complex nonlinear partial and ordinary differential equations, In this paper, such parallel-structured flexible arms are approximately modeled by a single-link flexible arm consisting of a flexible beam with the same boundary conditions as the parallel-structured one. Collision of the parallel-structured flexible arm and an undesirable obstacle is detected using the innovation process of Kalman filter based on the measured data of strain sensors pasted on the side of the arm. The proposed controller for the arm has the following two objectives: i) to rotate the flexible arm from the initial position to the desired position; ii) to safely suspend the rotation of the arm when the collision is detected.