A new position controller with gravity compensation for robot manipulators in joint space is proposed in this paper. The goal of position control problem for global asymptotically stability is achieved by using Lyapunov ’s direct method and LaSalle ’s invariance principle over the full non—linear mutivariable robot closed—loop system. In adition, this paper also presents experimental results on...

This paper addresses the visual servoing of robot manipulators in fixed-camera configuration considering a moving target. We propose a control scheme consisting of two loops: an inner loop, which is a joint velocity controller, and an outer loop which is an image-based feedback loop. We present the stability analysis and the experimental evaluation on a two degrees of freedom direct-drive plana...

A robust controller with chattering is proposed based on a simplified model of an electronic throttle system. The chattering term provides robustness against un-modeled nonlinearities, e.g., limphome nonlinearity, parameter dispersion, and friction phenomena. As the simplified model of the throttle system can be seen to correspond to a horizontal one-degree-of-freedom robot manipulator, the pro...

This paper introduces a new concept for designing a fuzzy logic based switching controller in order to control underactuated manipulators. The proposed controller employs elemental controllers, which are designed in advance. Parameters of both antecedent and consequent parts of a fuzzy indexer are optimized by using evolutionary computation, which is performed off-line. Design parameters of the...

This paper presents the design and implementation of a singularity-free tracking algorithm for robot manipulators using a hybrid system approach. A hybrid robot motion controller is designed to ensure feasible robot motion in the neighborhood of kinematic singularities. The hybrid control system has a two-layered hierarchical structure, a discrete layer and a continuous layer. The robot workspa...

This paper describes development and implementation of a decentralized continuous sliding mode motion controller for the robot manipulators. Adaptive fuzzy logic systems (FLSs), one for each robot axis, are employed to approximate almost a whole system dynamics. The structural properties of the robot dynamics are used for division of the each FLS to three simpler subsystems. This reduces the FL...

This paper addresses the problem of global output feedback, link position tracking control of robot manipulators. Specifically, a robust, Lyapunov-based controller is designed to ensure that the link position tracking error is globally uniformly ultimately bounded despite the fact that only link position measurements are available in the presence of incomplete model information (i.e., parametri...