A novel cross-coupled synchronizing control method of industrial robot for trajectory tracking

Improving the tracking accuracy of industrial robot is an important task for many motion control applications. This paper proposes a novel trajectory tracking method for serial industrial robot based on cross-coupled synchronizing control. Instead of improving the tracking accuracy for individual axes, we present a variable-weight position synchronous error, which can reduce the influence of dynamic nonlinearity through adjusting the error of each axis according to robot´s inertia distribution. Then a proportional and derivative (PD)-type synchronizing controller with cross-coupled structure is proposed and proven to guarantee asymptotic convergence to zero of both position and synchronization errors. Simulations conducted on a three-axis industrial robot demonstrate the effectiveness of the method.