Enumeration and Analysis of Variable Geometry Truss Manipulators

The variable-geometry truss or VGT, is a generalization of Stewart's most basic platform manipulator concept. In this paper, all possible basic forms of the truss-type manipulator are enumerated. These basic forms, or unit cells, are shown to be building blocks from which all truss-type manipulators are formed. Several manipulator concepts based on the unit cell construction are then presented as examples, including a new potentially superior form of Stewart's Platform. Finally, a general method for the forward kinematic analysis of VGT unit cells is described.