The Automatic Cutting Path Optimization Of Hull Parts Based On Genetic Algorithms

Hull parts cutting is the basic process of ship building.With the popularity of the CNC cutting machine,the traditional cutting methods have limited the efficiency of the cutting machine.To solve the problem of travelling a long way in air and frequency ignition,the paper proposes a division optimized method in consideration of the quality of cutting.This paper set the parts into two sections according to their sizes in the nesting figure and then take optimization separately.Firstly,small parts in the nesting figure can be divided into a plurality of regions according to their relative position.This paper establish a model based on Euler's theorem for continuous cutting of the little parts which in different region,and then introduce a way to generate Euler automatically by pretreatment of graph.We convert the continuous cutting model into the minimum spanning tree problem.As to making use of the genetic algorithms to solve it,the paper introduce a new coding method and genetic operators according to the characteristics of genetic algorithm.The example shows a good optimization result of the continuous cutting model.Considering the continuous cutting mode may be not suitable for the large parts,after the optimization of small parts of each region,the small parts of each region are taken as a whole firstly.Then,we divide large parts and the small ones nested in it into different categories,and then convert the optimization of the cutting path between large parts and the combination of little ones into GTSP.This paper also take the optimization with genetic algorithms.We propose the local optimization strategies for the shortcomings of genetic algorithm,and select the appropriate genetic parameters through experiment.Finally We take an example to prove the reliability of the algorithm.Based on the above principle,this paper design the hull parts automatic cutting path optimization system and test the system with some nesting figure with different number of parts.