TASK-ORIENTED OPTIMUM POSITIONING OF A MOBILE MANIPULATOR BASE IN A CLUTTERED ENVIRONMENT

A method for generating discrete optimal sequences of base locations f or mobile manipulators is presented that considers the task capability of the workspace in a cluttered environment. In implementation, the o bstacles and task trajectories are represented by 2(n) trees, so that a series of set operations are performed to characterize the manipulat or's configuration space into topological subspaces. By incorporating trajectory-motion-capable subspaces into the enumeration of the cost f unction, an optimum search technique is made applicable to the determi nation of a task feasible location. The method is then extended to a m ultiple positioning problem by concatenating the single optimization p rocesses into a serial multistage decision making system, for which an optimal set of decisions can be found through a computationally effic ient dynamic programming process. The computational paradigm of the pr esent method is coherent with topological workspace analysis, and thus applicable to task trajectories of arbitrary dimensions and shapes. T he effectiveness of the presented method is demonstrated through simul ation studies performed for a 3-d.o.f. regional manipulator operating under various task conditions.