Force Control of a Single-Link Flexible Arm

A force control scheme is proposed in this paper for flexible manipulators based on a concentrated parameter mechanical model. This model is then used to develop a simple feedback control law for the coupling torque between the motor and the flexible arm. This control offers a good regulation of the contact force exerted by the flexible arm on the object, measuring only the coupling torque without the need to measure the contact force and the angle of the motor. The control law is described as a gain integral controller. Another outer control loop based on a linear quadratic regulator (LQR) is added to improve the performance of the previous control. Also a collision detection algorithm is described for dealing with the force control problem