Measuring Modeling And Virtual Prototype Design Of Parallel-link Coordinate Measuring Machine

The coordinates measuring machine(CMM) is one kind of large-scale precise intellectualization measuring equipment which integrates machinery, optics, electronic, the numerical control technology and the computer technology into a body, and has become an indispensability essential measurement equipment in the modern industry inspect, the quality control and the manufacture technology. The CMM is divided into two types: serial-link CMM and parallel-link CMM .That people has study serial-link CMM for forty years. Measuring accuracy and measuring efficiency of serial-link CMM is approaching the theory limit because of some defect of serial-link structure inherence, having no way to improve again. The parallel-link CMM has the dual characteristic with serial-link CMM, therefore the parallel-link CMM is able to complement the limit in application and improve the combination property such as measuring accuracy and measuring efficiency. There are the hope for the development and exploitation of new generation CMM. However, the development between the serial-link CMM and the parallel-link CMM is extremely unbalanced. Parallel-link CMM research rise in 90's later stage just now, have a lot of theory and the technology problem remain to be solved. Therefore, the job carrying out parallel-link CMM research is very necessary. Especially, the research for the most representative 6-SPS type parallel-link CMM has common significance.In nature, the measuring model of parallel-link CMM is equated with the solution of forward kinematic. The solution of forward kinematic is high-order nonlinearity multi-solution problem. It is very difficult to find the solution of forward kinematic, so people have made much effort to solve this problem, basically, by analytical method and numerical method. Inverse kinematic mathematic model of parallel-link CMM is established in thesis firstly. The solution of forward kinematic is obtained by improving fundamental genetic algorithm, which overcomes the shortcoming of analytical method and numerical method, and receives very good effect.Virtual prototype model of 6-SPS parallel-link CMM is established making use of the ADAMS software in this thesis. Virtual prototype technology is used for kinematic simulation, dynamic simulation, impact detecting, error analysis etc, and is the basis of building physics prototype. Virtual prototype technology is used to advance a novel solution for forward kinematic, which simplifies the solution of forward kinematic, and creates an advantage for system optimization to parallel-link CMM in the future.