Optimum design of a class of fault tolerant isotropic Gough-Stewart platforms

Optimal geometric design is of key importance to the performance of a manipulator. First, this paper extends the work in Y. Yi, et al., (2004) to generate a class of isotropic Gough-Stewart platforms (GSPs) with an odd number of struts. Then, it develops methods for finding a highly fault tolerant GSP from that class. Two optimization criteria are considered, isotropy and fault tolerance. To meet the mission critical needs imposed by laser weapons applications, nine-strut isotropic GSPs that retain kinematic stability despite the loss of any three struts are found. First, we develop methods for generating a five parameter class of isotropic nine-strut GSPs. Next, new measures of fault tolerance are introduced and used to optimize the free parameter space. The optimized design is much more fault tolerant than the GSP currently baselined for the airborne laser.