Design Of Control System And Research On Polishing Experiment Of The Micro-Polishing-Robot

IntroductionIn recent years, as Chinese economic taking off and the rapid development of manufacturing industries, especially after the accession to WTO, our country is on the way to world's manufactury center. Machine die Technology------in particular the level of technology producing precision, complex, large-scale and long-life die, has become an important measure of an enterprise or a country's manufacturing level. The standard of evaluating merits of die is the die precision, yet the center tache of affecting precision of die is the die processing technology. Process of die usually includes two contents: rough and finishing process. Roughing of die has achieved high automation, however, finishing process still remain in handwork. Handwork is not only low efficiency and unstably machining quality, but also requires the operators having higher skills, which constraining the development of high quality free-form die's manufacturing.Regarding the finishing process of large-scale die's free-form surface, it needs a large polishing equipment to polish based on the traditional processing,the cost is large. Meanwhile there is a scope for processing accuracy, stiffness, stability and rapid movement numerous technical difficulties. The subject present a new technology idea that use the small finishing equipment for the processing of large free-form surface, the surface free-from the research and development of micro-positioning polishing robot free surface geometry based on its own information and information technology in road surfaces free of large-scale self-lapping and polishing.This paper carries on based on the National Natural Science Fund Project" Research on a Micro-polishing Robot that polishing and self-positioning on the free-form surface ", it completes the design of Micro-Polishing-Robot's control system's hardware and software. the machining experiment of Micro-Polishing-Robot was done based on control system, which validating the feasibility and validity of robot polishing large-scale free-form surface.System structure and work process of Micro-Polishing-RobotDesigned in accordance with technical requirements of the micro-robot polishing as shown in Figure 1, as can be seen through the figure polishing robot mainly consists of three parts: body structure, processing structure and walk structure. Since Micro-Polishing-Robot consisting of specific division function-modules, it is thought the use of modular design, according to the functional requirements of the design of the modules separately, the inter-module connection with the chassis as an organic whole. The design of the Micro-Polishing-Robot institutions based on modular design as shown in table 1.Design of Control system of Micro-Polishing-RobotAccording to Micro-Polishing-Robot's movement and process require, this subject set up a open control system based on programmable controller PMAC and IPC. IPC's CPU with PMAC's CPU constitute upper and lower dual-processor microprocessor structure. As upper microprocessor, IPC achieves the programming, simulation, image processing, human-computer interface, network capabilities, and other non-real-time motion planning of mission; Being a lower microprocessor, PMAC achieves servo control, trajectory interpolation, programmable logic control and sensor information processing tasks such real-time mission. The control system's hardware structure of Micro-Polishing-Robot as shown in Figure 2.Micro-Polishing-Robot's control system can be divided into two part, one is to control Micro-Polishing-Robot's movement, the other is to control polishing, meanwhile, the two parts of control should be coordinated in order to achieve Micro-Polishing-Robot polishing large-scale free-form surface process. Developed the human-machine interface by using powerful development software Visual C + + 6.0, through the man-machine interface, we can do various operations to Micro-Polishing-Robot.The software of Micro-Polishing-Robot's control system use modular design, Software architecture can be divided into three modules: Procedure operation module, main control module and real-time status display module.The machining experiment research of Micro-Polishing-RobotThe machining experiment of Micro-Polishing-Robot was done, based on Micro-Polishing-Robot's control system. A large free-form surface of JETTA car was conducted a test workplace. In this region, the original surface roughness value was about Ra 0.296μm. The results of the machining experiment showed that the surface roughness value had been about Ra 0.107μm after machined by flexible tool, significantly improving the surface roughness value of surface. It can be seen that Micro-Polishing-Robot used in precision machining and polishing is entirely feasible. The orthogonal experiment and single-factor experiments have been done of Micro-Polishing-Robot, find the best process factor and the importance of the factors. Through the experiment, we can know the influence of factors that influencing the surface roughness by the strong to the weak order: robot speed, sandpaper size, polishing pressure and tool rotational Speed, followed by the optimal level: 0.5mm/s, 600M, 25N, 4500r/min.