This paper analyses the reasons for resulting in the instability of mobile manipulator. Several methods of stability analysis and errors compensation are introduced, including the theories, the modeling processes and their characteristics. The significance of analysing the stability and compensating the errors are expounded. In addition, the corresponding applications are also discussed. Finall...

In this paper a gain scheduling approach is proposed for the hybrid force/velocity control of an industrial manipulator employed for the contour tracking of objects of unknown shape. The methodology allows to cope with the configuration dependent dynamics of the manipulator during a constrained motion and therefore a significant improvement of the performance results. Experimental results obtai...

A power assisted gait rehabilitation robot system by which a patient who has difficulty in walking can exercise is proposed. Our developed system consists of a robotic manipulator which can adjust the height of the system according to the user and a mobile base with two-driving wheels. It is similar to the architecture of a mobile manipulator. The neural network based control algorithm for a mo...

In this paper, we use principle of virtual work to obtain the direct dynamics analysis of a 3-RRP spherical parallel manipulator, also called spherical star-triangle (SST) manipulator (Enferadi et al., Robotica 27, 2009). This manipulator has good accuracy and relatively a large workspace which is free of singularities (Enferadi et al., Robotica, 2009). The direct kinematics problem of this man...

Singularity is an inherent characteristic of a closed-chain manipulator. This paper presents an approach to singularity analysis of the planar 3-RRR parallel manipulator. On the basis of screw theory, the motion/force transmission analysis of the manipulator is first achieved. The singularity is classified into three types: constraint singularity, input transmission singularity, and output tran...

The manipulator trajectory tracking control problem revolves around computing the torques to be applied to achieve accurate tracking. While this problem has been extensively studied in simulations, the real-time results have been lacking in the robotics literature. In this paper, we present the experimental results of the real-time performance of model-based control algorithms. We compare the c...

A novel composite control scheme for a manipulator with flexible links and joints is presented that uses the singular perturbation technique (SPT) to divide the manipulator dynamics into reduced order slow and fast subsystems. A neural network controller is then applied for the slow subsystem and a state-feedback H∞ controller for the fast subsystem. Results are presented that demonstrate impro...

Owing to load variation and unmodeled dynamics, a robot manipulator can be classified as a nonlinear dynamic system with structured and unstructured uncertainties. In this paper, the stability and robustness of a class of the fuzzy logic control (FLC) is investigated and a robust FLC is proposed for a robot manipulator with uncertainties. In order to show the performance of the proposed control...