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Object handling is one of the most important applications of cable-suspended robots, which can be obtained by use of a gripper as its end-effector. In this paper, a novel cable-driven multi-finger gripper assembled on a cable-suspended robot has been presented. Using lock/unlock mechanisms, the under-actuated finger mechanism has been designed to have a human like motion. A cable-suspended robot structure with 3 position degrees of freedom is also proposed by employing active/passive cables in such a way that makes it capable of resisting external moments, while it may be simplified to a spatial point-mass cable robot during positioning operation. Furthermore, the robot workspace has been... 

In this paper, we introduce a new method and new motion variables to study kinematics and dynamics of a 6 d.o.f cable-driven robot. Using these new variables and Lagrange equations, we achieve new equations of motion which are different in appearance and several aspects from conventional equations usually used to study 6 d.o.f cable robots. Then, we introduce a new Jacobian matrix which expresses kinematical relations of the robot via a new approach and is basically different from the conventional Jacobian matrix. One of the important characteristics of the new method is computational efficiency in comparison with the conventional method. It is demonstrated that using the new method instead... 

The objective of this paper is designing, modeling and wrench feasible workspace analysis of a 3D cable suspended robot as IRPM (Incompletely Restrained Positioning Mechanism). This type of robots supports a load platform in space by less than or equal to six spatially arranged cables. We use the model of 6 cables spanned in the same manner as a Stewart parallel mechanism. This mechanism is suitable for the accurate positioning of heavy loads. Concentrating on the operations of heavy loads handling, studying the workspace and ways of increasing it is of high importance. Several workspaces exist amongst which the constant and total orientation statically reachable combined and wrench feasible... 

In under-constrained spatial cable suspended robots, maximum number of cables are equivalent to the number of degree of freedom, therefore the equations of kinetostatic have unique solutions and invention of positive cable tensile forces in these robots must come into being by redundant cables, springs or by Moving Platform (MP) weight. In this research, MP weight is considered to create tension in cables so both increasing workspace volume and decreasing possibility of cable encounter with together can be created because of using less cables. The range of MP weight to generate tension in cables is calculated by using Interval method, optimum weight is selected and then optimal tension... 

Cable-driven parallel robots have several outstanding characteristics that make them unique in many robotic applications. Since cables can only pull, one of the most important issues associated with these robots is obtaining their workspace. In this paper a spatial translational cable-driven robot with active/passive cables is considered and its workspace is investigated from several points of views. First the moment resisting capability of the robot is discussed and the effects of some robot's parameters on the workspace are studied. Then, both force-feasibility and moment-resisting capability of the robot are considered to find the region where the end-effector may exert the required... 

This paper presents a kinematics and workspace analysis of cable-suspended manipulators with elastic cable. The mechanics of extensible cable with a deflection to its selfweight are studied. The problem of evaluating the workspace is approached by using a modified formulation for a deformable cable. The proposed algorithm for testing whether a given configuration lies within the reachable workspace is applied. Starting with a general statement of the kinetic equations of the elastic cable and incorporate cable flexibility into workspace generation. This algorithm is verified through simulation results of various cable-suspended robots. © 2008 IEEE