Research Of NC Cutting Route Optimization For The Hull Parts

The hull parts cutting is one of the shipbuilding processes, including three sections: markline marking, the inner hole cutting and the outer contour cutting.The cutting process is no reasonable planning that the marking route in air is very long, the number of cutting ignition frequency and the cutting route in air long in the actual production,which the results is the low cutting efficiency and a waste of cutting costs. This research work is mainly focused on how reasonable and effective to reduce the route in air and to improve the efficiency of the cutting machine, reducing cutting costs.Based on the characteristics of the hull parts cutting route optimization, the marking routes optimization problem, the problem of the hull parts graphics pretreatment technology, within the hole cutting route optimization problem and the hull parts consecutive cutting problem will be reached, respectively, using different research method. The specific studies are as follows:(1) Direct parts stratification and parts directionary into two important basic problems in computer graphics:point and polygon containment relationship recognition and polygon direction identification.Traditional algorithms can not adapt to identify the relationship of point and the polygon containing arc, this paper improved algorithm and examples to verify the performance. The Qi function method discriminant point improvements based on edge polygon containment relationship and correction algorithm for polygon containing arc. The examples show that the two algorithms can effectively determine a point and polygon containment relationship.Recognition algorithm based on three-pole serial number size of polygon direction. Identify polygons direction, just to determine the size of the serial number of vertices in the polygon vertices sequence three polygons arbitrary extremal can accurately polygon direction. The examples show that the algorithm based on three-pole serial number of polygon direction recognition is simple, stable and efficient.(2) According to the features of the marking, taking the marking order and the marking direction as the parameters and taking the minimum marking path in air as the objective, a math model of marking optimization is established on the base of hybrid encode. The use of "greedy strategy " initial population, improve the fitness of the population. The different strategies have been used for the marking order and the marking direction. The random mutation operator maintain the diversity of the population. The simulation results show that the model is effective, which can effectively reduce the idle marking path.The marking route planning problem would be regarded as the Traveling Salesman Problem. According to the special of the marking path, a planning model was proposed based on an improved ant colony optimization algorithm and Max-Min ant system was applied to optimize the problem. By analysis and simulation, the best value range and combinatorial optimization settings of parameters was given. Then the comparison with Genetic Algorithms was given. The simulation results show that the optimization model is effective, which can effectively reduce the idle marking path.(3) Based on the famous konigsberg Seven Bridges and Euler’s theorem, the establishment of the hull parts consecutive cutting model provides a theoretical foundation for the realization of continuous cutting. Into the the hull parts consecutive cutting issues to construct a minimum spanning tree problem in graph theory, the establishment of a model based on genetic algorithms to solve. Introduced a sequence encoding method, CBMST initialize population, PMST crossover operator and a new mutation operator to improve the performance of the algorithm. The simulation tests proved genetic algorithms and the minimum spanning tree-based continuous cutting model can effectively reduce the number of cutting ignition and the length of the route in air, improve the efficiency of the cutter.(4) Based on artificial bee colony algorithm, problem solving within the hole cutting path optimization algorithm model and implementation steps were constructed. By artificial fish swarm algorithm and genetic ant colony algorithm comparison show that the artificial bee colony algorithm has a strong advantage in solving the inner hole cutting path optimization problem, and can achieve the optimal solution and convergence speed. Through simulation experiments, analyzed and discussed the impact of the ABC algorithm in three main parameters select the algorithm performance, and given the choice of the parameters. Bore containing parts, combined with continuous cutting technology and artificial bee colony algorithm to optimize continuous cutting within the hole and the hole parts, cutting additional shortest path, and the rationality of the model is verified by examples.(5) Based on the study of four basic problems about the hull parts cutting route optimization, the hull parts cutting path optimization software system is designed,including input and output interfaces of the software, the cutting path optimization, optimize data statistics, the comparison of before and after the path optimizing, cutting path simulation, part interference checking function. Finally, the application of the software system instance is given.