Dynamics of single-link manipulator under a novel control law

This paper presents a theoretical and experimental study on the dynamic performance of a single-link manipulator under the influence of a novel control law. The novel control law emulates the viscoelastic material behaviour and is termed Four-Element (FE) control law. The analysis of the manipulator is carried out using two control schemes, namely, novel control law and conventionally used PID control. Both controllers are optimally designed and compared for set-point tracking. Under both control laws, the manipulator’s performance is studied for the two different feedback noise models, namely, sinusoidal and white Gaussian noise. The experimental results validate the faster response of the proposed FE control law for the step input. The viscoelastic law provides more accurate positioning and robust behaviour against variation in amplitude and frequency of the feedback noise than PID. The single-link manipulator is also analyzed for trajectory tracking. The corresponding optimized controller gains are obtained to minimize the trajectory error and to reduce the applied torque variations. The resilience and high damping capacity property of viscoelastic material are successfully emulated by the FE control law, which helps to deal with uncertainties and in rejecting external disturbances.