Static analysis of spatial parallel manipulators by means of the principle of virtual work

It is presented a comprehensive approach for the static analysis of spatial parallel manipulators using the principle of virtual work, equipped with a recursive and systematic formulation, which is intended for conducting an efficient manipulation of the kinematics associated with the problem. Thus, it is possible omitting all internal forces and nonworking external constraint forces in the problem formulation. As a result, the actuator drive forces and/or torques can be directly related with the external loads supported by the manipulator, including the weight of the mobile platform and also the weight of the links of the connecting legs. A thorough understanding of these forces and/or torques is important for proper sizing of actuators at the design stage. In order to prove the feasibility and the validity of the proposed method, two fully detailed examples are presented.

► Systematic and efficient formulation of the kinematic aspects of the static problem. ► Computation of the virtual rotational displacement of bodies is avoided. ► Integral and efficient solution of the static problem. ► A computational algorithm is provided. ► Highly systematic methodology easy to apply to an arbitrary parallel manipulator.