The workspace of a parallel manipulator is usually smaller than the size of the robot itself. It is important to derive new structures that enjoy the advantages of parallel manipulators and also have a large workspace. In this paper we present two configurations of similar structures RRRS and RRSR with rotating links. The RRRS structure has a relatively large workspace—larger than the size of t...

Compared to serial robots, parallel kinematic machines (PKM) offer superior properties. However, modelling and analysis of PKMs are challenging tasks due to their complicated kinematic structure. In this paper we present methods to analyze the workspace of a class of 6 degree-of-freedom (dof) PKMs with constant leg length. These methods apply interval analysis in order to calculate the orientat...

In this report, we present the analysis of a 6 DOF robot end-effector built to study telerobotic assembly of NASA hardwares in space. Since the end-efector is required to perform high precision motion in a limited workspace, closed-kinematic chain mechanism is chosen for its design. A closed-form solution is obtained for the inverse kinematic problem and an itemtive pmedure employing Newton-Rap...

This paper presents the Collaborative Task Manager (CTM), which offers a unified management of shared tasks and commitments involving the usage of heterogeneous applications. The CTM supports the synchronization of user activities, and the management of workspace awareness, in customized collaboration environments. In particular, the CTM enables the user to resume the activity context of a task...

This paper describes new concepts and prototype software developments for the NC-programming of parallel machine tools. Important characteristics of the system are the integration of a machine workspace model with the CAM system and the integration of a NC-simulation system with the postprocessor. During tool path generation, each tool posture is checked for feasibility by a fast interrogation ...

In this paper, we study the problem of large force/torque application using robotic systems with limited force/torque actuators. For such systems, the available workspace may be smaller than its reachable workspace. It is shown that redundancy increases the force capability and workspace of a robotic system. To plan redundant manipulator postures during force tasks, a new method based on a min-...

The paper addresses the optimal design of parallel manipulators based on multi-objective optimization. The objective functions used are: Global Conditioning Index (GCI), Global Payload Index (GPI), and Global Gradient Index (GGI). These indices are evaluated over a required workspace which is contained in the complete workspace of the parallel manipulator. The objective functions are optimized ...

This paper addresses the workspace analysis of two 3-DOF translational parallel mechanisms designed for machining applications. The two machines features three fixed linear joints. The joint axes of the first machine are orthogonal whereas these of the second are parallel. In both cases, the mobile platform moves in the Cartesian x−y−z space with fixed orientation. The workspace analysis is con...

Perhaps the most common configuration for planar manipulandums used in motor control studies is the serial five -bar linkage, but this design suffers from strongly directional inertia and force production characteristics. An alternative parallel-link design whose properties are less direction-sensitive across the workspace has been used in wrist-motion studies, but has never been scaled up for ...

We present an algorithm to determine all the possible geometries of Gough-type 6 d.o.f. parallel manipulators whose workspace has to include a desired workspace. This desired workspace is described as a set of geometric objects, limited here to points and segments, which describe the desired locations of the center of the moving platform. It is assumed that the orientation of the platform is fi...