Modeling of dynamic-elastic deformation error for a collaborative robot

In the operation of a collaborative robot, the inertial force, gravity force, and other factors can cause elastic deformation of links and joints, and hence results in considerable deviations from the desired trajectory. However, the effects of inertial force, gravity force, and Jacobian matrix are rarely considered in common deformation analyses. This paper proposes a method for modeling dynamic elastic deformation of collaborative robots including joint torsional stiffness and complementary stiffness. Firstly, the dynamics equation was established based on the Newton-Euler method, and the driving torque of the joint was analyzed. Secondly, a dynamic-elastic deformation error model was established based on the joint torsional stiffness and complementary stiffness. Finally, the simulation results show that the established dynamic error model has good predictability, and the relative error is less than 1.63% compared with the ADAMS simulation results.