A novel velocity estimation method for robotic joints based on inverse hyperbolic sine tracing differential algorithm

This paper presents a novel nonlinear velocity estimation method for robotic joints based on inverse hyperbolic sine tracing differential algorithm. Unlike the conventional methods that using the motor-side position measurements to obtain the joint velocity, this paper addresses the problem of joint velocity estimation that using the link-side absolute encoder data, so that the kinematic error caused by the mechanical transmission can be avoided effectively. Based on the inverse hyperbolic sine tracing differential algorithm, a velocity estimator is designed to obtain the high precision of the joint velocity and suppressing the measurement noise effectively. The stability of the proposed velocity estimator is proved by using the Lyapunov theory. Finally, experiments are performed to verify the effectiveness and advantage of the proposed velocity estimation method.