Research On The Key Technology Of Tool Automatic Distribution In NC Workshop For JIT Production

In modern NC workshop, with the optimization of NC machining parameters and reduction of machining time, the long-time of auxiliary production, such as the tool distribution process, has become a more critical problem. In domestic aviation manufacturing fields, the current tool distribution efficiency and management are at a relatively low level. Therefore, the production efficiency cannot be further improved. Aiming at the above problems, the key technology of tool distribution in NC workshop for JIT production was studied in this paper to achieve lean production. As a result, the tool distribution process was significantly optimized and its effective management was achieved for JIT production. This paper mainly contains the following research:(1) For the vehicle scheduling problem, a two-stage method was proposed based on sweep algorithm and genetic algorithm. A more effective matrix sweep method was developed to allocate distribution missions. Operations of the genetic algorithm were then studied according to problem’s characteristics to optimize the distribution order. The case study validated the effectiveness and superiority of this hybrid algorithm, which could effectively dispatch the tool distribution vehicles.(2) The vehicle routing problem was studied on two levels: On the global static level, the environmental model was constructed, and single vehicle’s path planning was designed upon A*. On the local dynamic level, vehicle conflicts were detected and responses were designed according to a certain obstacle avoiding strategy. Finally, the whole routing algorithm was acquired upon the global optimal result by using the local planning method, to achieve vehicle’s dynamic obstacle avoidance.(3) The safe communication method for AGV navigation was studied based on RFID and visual aids. The ground-vehicle control system was designed, and the automatic tracking technology was developed. The visual navigation method was put forward based on RFID, and the mistake proofing technique for tool pick-up was developed, so as to ensure the accuracy of tool distribution.(4) The system was generally designed based on the demand analysis of tool distribution and management. Then, the distribution management system was designed based on B/S mode, as well as the distribution monitoring system based on C/S mode. As a result, the critical functions were achieved, such as tool application, tool distribution, vehicle scheduling, vehicle navigation, etc.