In an isotropic configuration, the sensitivity of a manipulator in both velocity and torque errors is at a minimum and the manipulator can be controlled equally well in all directions. If the Jacobian matrix is isotropic throughout the entire workspace, manipulator is fully-isotropic and therefore the condition number of the Jacobian matrix is one. Manipulator design can be expressed as a function of workspace requirements. This work presents a hybrid fuzzy logic - genetic algorithm (FL-GA) method for optimization and dimensional synthesis of a 3PRR (prismatic- revolute- revolute) planar parallel manipulator for a prescribed workspace. The algorithm is made of classical genetic algorithm coupled with fuzzy logic. The fuzzy logic controller monitors the variation of genetic algorithm variables during the first run of GA and modifies the initial bounding intervals to restart the next run of the algorithm. Links of robot are minimized while desired workspace is achieved.

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