Abstract:
A linear motor-driven variable configuration parallel multi-dimensional vibration platform with adjustable balance pose is designed and developed based on 3-P(4S) configuration. The constraint screw theory is used to analyze the DOF (degree of freedom) properties of two configurations of which the sub closed-loops are initially installed as a parallelogram and trapezoid. Kinematic models of position and attitude of two configurations are established, the relationship between pose output and driving input is studied, and the nonlinear constraint equations of mechanism with trapezoid installation are solved by iterative search method. According to pose analysis, reachable workspace of mechanism under two initial installation conditions are obtained by using inverse solution search method and positive solution ransacking method respectively, as well as the adjoint rotation workspace under trapezoid installation. By numerical example, the results of the theoretical analysis is verified. Through motion simulation of the mechanism, kinetic output features of the vibration platform under different initial configuration are studied. Motion experiment of physical prototypes is conducted based on theoretical analysis and simulation results. The results of theoretical calculations, simulation analysis and experiment are compared, and the validity of theoretical analysis and feasibility of the prototype engineering applications are verified further.