The Kinematics And Dynamics On The Cross-rod Parallel Machine Tools

Currently, the parts such as the blade or the impeller with complicated and unformulated curve and surface have already been being manufactured by parallel machine tools which is characteristic of multi-axis linkage for itself. In 2009, EXECHON 700 developed by EXECHON Company in Sweden and applied to the actual production, the new generation of parallel machine tool indicated that parallel machine tools can partly replace the traditional 5-axis linkage machining center in processing of those parts with complicated and unformulated curve and surface,and that it has superiority in efficiency and precision. By virtual of simple structure, the price of the parallel machine tools should be much cheaper than the 5-axis linkage machining center,however,the actual price is more expensive than the 5-axis linkage machining center by view of the technical monopoly. Therefore, the mastering and application of technology on parallel machine tools and research into problems relevant to parallel machine are much significant.In this thesis, the main research contents as follows:The cross-pole parallel machine tools of 6-SPS with 7 axes and 6-axis linkage by the Harbin Measuring & Cutting Tool Group Co., Ltd as subject, the kinematics and dynamics problems of cross-pole parallel machine tools were studied and analy- zed, and the forward solution of the kinematics problems and dynamics problems were studied emphatically. In the basis of solving of kinematics problems, the interp- olation problem and servo control problem of manufacturing complex curve and sur- face with parallel machine is explored, then the design scheme of CNC system of the parallel machine tools is provided.In the research of kinematics problems,with Lie Groups and Lie Algebras, the quick and concrete geometry algorithm in reversed solution of kinematics problems in parallel machine tools was created, providing the basic facility of manufacturing complex curve and surface. As the introduction of Lie Groups and Lie Algebras, the forward solution of the kinematics problems transformed into reverse solution, the i- ntricate forward solution in parallel machine tool is radically solved.In the basis of analysis of kinematics problems, the interpolation of helical cur- ve in parallel machine tools is studied. The study created the method to interpolate the helical curve using Taylor Series and Expand Digital Integral, gave manufacturi- ng accuracy constraints on the feeding speed, still analyzed the procedures of the int- erpolation algorithm. In the basis of the solving of interpolation algorithm, the realiz- ation of servo system of parallel machine tools was studied, in conclusion, to control the servo electric engine with CNC position servo control card made by FANUC.The dynamics problems of parallel machine were studied by Lie Algebras and Kane equation,the screw form's Kane dynamics equations were established intr- oduction of the partial velocity screw, and the solution was also explored.Finally, the virtual prototype model was designed and simulated in the commer- cial dynamics simulation software Adams. The simulating results were compared wi- th the results that came from the solution of kinematics problems and dynamics pro- blems in this thesis.