The Variable Topology Truss (VTT) is a new class of self-reconfigurable robot that can reconfigure its truss shape and topology depending on the task or environment requirements. Motion planning and avoiding self-collision are difficult as these systems usually have dozens of degrees-of-freedom with complex intersecting parallel actuations. We present a fast algorithm to compute the configuration space of a node so that path planning can be done quickly using cell decomposition and graph search.