Research On Kinematic Calibration And Experiment Technique Of Parallel Machine Tools

Aiming at the need of practice, this dissertation is focused on kinematic modeling, error parameters identification model and error compensation experiment method research of a tripod-based parallel kinematic machine tools with parallelogram struts. The main achievements are obtained as follows.Based on the theory of robot mechanism, the inverse and forward kinematic analysis of 3-HSS parallel machine with geometric errors is formulated. The result of simulation shows that the control accuracy of the machine is greatly improved, by taking the orient errors of the struts into the parameters of kinematic model.After error source is analyzed and the error mapping function is demonstrated by use of error separating technique, a parameter identification model which can separately identify the source errors effecting the uncompensable and compensable errors is presented.The method of twice error-measurement using laser interferometer is proposed. It enables orient errors and positional errors to be effectively separated. Consequently, the calibration experiment modifying the inputs of the system is carried out, and the result shows that the accuracy of machine is greatly improved.The result is successfully applied in the development of vertical parallel machine tools.