Robust tracking control for a class of electrically driven flexible-joint robots without velocity measurements

Trajectory Tracking of Flexible-Joint Robots Actuated by PMSM via a Novel Smooth Switching Control Strategy

“…An adaptive fuzzy voltage control strategy for a DC-driven rigid-joint robot with uncertainty compensation is proposed in [9]. In [10], an observer-based robust control strategy for DC-driven flexible joint robots without speed sensors is proposed. An adaptive fuzzy control strategy for a PMSM-driven rigid-joint robot is proposed in [11], but this article did not make a specific analysis of the controller performance.…”

Nonlinear Control of a Flexible Joint Robotic Manipulator with Experimental Validation

“…The flexibility in joint is modelled as a linear torsional spring [16]. Using Euler Lagrange equation, the equations of motion for an electro-mechanical system can be derived.…”

“…In [16], a robust control law based on a back-stepping technique for tracking trajectory of manipulators has been proposed, in which only armature current and link position are measured for feedback purposes. Despite these efforts [14] to [16], most of the reported back-stepping techniques suffer from two limitations; The first is that the systems under consideration did not have time-varying parametric uncertainties. The second limitation is related to the level of complexity resulting from iterative differentiations of nonlinear virtual functions and thus leading to a complex and computationally expensive algorithm.…”

“…Another study reported [13] presents a controller based on adaptation law for a flexible joint robot to improve the trajectory tracking in the presence of time-variable uncertainty in the system's parameters. A traditional back-stepping approach has been applied successfully to solve the control problem of robots with flexible joints [14] to [16]. However, in these approaching, the torque is assumed…”

Control of Trajectory Kinematics for Flexible Manipulators Applying Integral Variable Structure Strategy

“…A novel observer-based robust dynamic feedback without velocity measurements was developed [20] resulting tracking error as small as possible, In case of the set-point regulation problem it can be simplified to a linear time invariant controller. A variable structure control method with a mathematical tool is applied [21] to control errors in a controller that is robust to the model uncertainties.…”