Optimal redundancy resolution for kinematically redundant parallel manipulators

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2014
Tunç, Tansel Sıtkı
In this study, the redundancy resolution of kinematically redundant parallel manipulators has been investigated as an optimization problem. The emerging optimization problem has been solved globally using a hybrid genetic algorithm. This algorithm has been applied as an example to a planar parallel manipulator which has four degrees of freedom. It has been assumed that the manipulator is used so that only the tip point of its end-effector is controlled. Therefore, the rotation angle of the end effector has been let free. As a result, the redundancy degree of the manipulator has become two for the planar point positioning task which requires two degrees of freedom. In the definiton of the optimiziation problem, the limits of the prismatic joints have acted as inequality constraints and the kinematic relationships, which consist of the loop closure and input-output equations between the tip point position and the joint variables, have acted as equality constraints. It has been assumed that the revolute joints have no limit. Various performance functions such as potential energy, kinetic energy and total power have been used for the purpose of optimization. By minimizing each function separately, different optimal redunancy resolutions have been obtained at the position, velocity and acceleration levels.

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Citation Formats
T. S. Tunç, “Optimal redundancy resolution for kinematically redundant parallel manipulators,” M.S. - Master of Science, Middle East Technical University, 2014.