Jung Won Yoon, Jeha Ryu, Yoon-Kwon Hwang
The Journal of Mechanical Science and Technology, vol. 24, no. 5, pp.1151-1162, 2010

Abstract : This paper proposes an optimum design method that satisfies the desired orientation workspace at the boundary of the translation workspace while maximizing the mechanism isotropy for parallel manipulators. A simple genetic algorithm is used to obtain the optimal linkage parameters of a six-degree-of-freedom parallel manipulator that can be used as a haptic device. The objective function is composed of a desired spherical shape translation workspace and a desired orientation workspace located on the boundaries of the desired translation workspace, along with a global conditioning index based on a homogeneous Jacobian matrix. The objective function was optimized to satisfy the desired orientation workspace at the boundary positions as translated from a neutral position of the increasedentropy mechanism. An optimization result with desired translation and orientation workspaces for a haptic device was obtained to show the effectiveness of the suggested scheme, and the kinematic performances of the proposed model were compared with those of a preexisting base model.

Keyword : Parallel manipulator; Optimization; Genetic algorithm; Haptic device; Translation and orientation workspaces; Isotropy