This paper investigates the fault-tolerant control of hyper-redundant spatial manipulators. The standard resolved rate control law using the pseudoinverse is modified to account for joint failures. To combat the problem of extremely high joint velocity solutions generated near singular configurations by the pseudoinverse, the singularity robust inverse is employed. A method to compute an optima...

There are several ubiquitous kinematic structures that used in industrial robots, with the most prominent being a six-axis angular structure. However, researchers experimenting task-based mechanism synthesis could provide higher efficiency custom optimized manipulators. Many studies have focused on finding efficient optimization algorithm for robot These manipulators, however, usually from simp...

This paper looks at the control of mechanical impedance of the so-called G’ough-Stewart class of parallel platforms. Two methods of compliance control are presented. One is based on global potential energy functions that have previously been applied to controlling serial manipulators and electrodynamically levitated platforms. The second uses the exponential map to associate finite displacement...

This paper presents an algorithm for generating trajectories for multi-degree of freedom spatial linkages, termed constrained parallel manipulators. These articulated systems are formed by supporting a workpiece, or end-effector, with a set of serial chains, each of which imposes a constraint its movement. Our goal is to plan trajectories for systems that have workspaces ranging from two throug...

This work investigates new kinematic features of parallel manipulators. It is well known that parallel manipulators admit generally several direct kinematic solutions for a given set of input joint values. The aim of this paper is to characterize the uniqueness domains in the workspace of parallel manipulators, as well as their image in the joint space. The study focuses on the most usual case ...

The significant advantages of parallel robots over serial manipulators are now well known. However, they still pose a serious challenge when considering their kinematics. This paper covers the state-of-the-art on modeling issues and certified solving of kinematics problems. Parallel manipulator architectures can be divided into two categories: planar and spatial. Firstly, the typical planar par...

This paper proposes a hybrid numerical method (HNM) to solve the inverse kinematics of a class of spatial flexible manipulators modeled b y mass/spring (mass-lumped stations and masslessspring fields) modeling method. HNM includes two parts: one is an implicit recursive numerical method (IRNM) which is used to f ind a better approximate solution to the inverse problem, the other is a global ite...

The separation of time and space in processing a sample greatly simplifies the design of automation for clinical testing. The efficient spatial arrangement of analytical units and sample manipulators has become a more complex task because of the degree of automation required on today's state-of-the-art analyzer. Minimization of sample volume and the reduction of overall analyzer size further co...

This paper considers finite-time position control of robot manipulators. The robot manipulators are modeled by discontinuous differential equations. In this paper, we prove that the Nakamura’s local homogeneous controller based on a control Lyapunov function is valid to the position control of the robot manipulators, and show the effectiveness of the controller by experiments. Moreover, we comp...

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar muster-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schill...