Numerical Implementation and Comparison Between the Viscous, Fractional and Hysteretic Damping Models of a Rigid-Flexible Planar Manipulator

This work treats the problem of modeling and identification of the structural damping of the flexible link of a rigid-flexible manipulator. Besides dissipating energy due to the joint friction, like in rigid robots, flexible robots also dissipate energy due to structural damping that results in the time amplitude decay of the flexible arms oscillations. This behavior is traditionally tackled recurring to viscous, fractional Voigt-Kelvin or hysteretic models. In this paper, for the latter two approaches, numerical approximations are used for their numerical implementation. Furthermore, a heuristic method based on the joint and flexible arm time responses is applied and compared with other methods, like recursive least-squares, to identify the large set of parameters of a flexible manipulator, including the inertial and joint friction parameters.