基于改进蜘蛛群集算法的木薯收获机块根拔起速度优化.

When the cassava tubers are lifted up by the dig-pull cassava tuber harvester, the harvester has low power consumption and a high adaptability to the soil. However, the control precision of the lifting velocity of cassava tuber is low, thus, the broken and loss rate of the cassava tubers are larger in the cassava tuber harvesting. And the control precision of the control system of the tuber lifting velocity mainly depends on the quality of control system's control parameters. Whether the optimal control parameters could be obtained by the optimization algorithm of the control system's control parameters determines the quality of the parameters. Therefore, the optimization algorithm of the control parameters of the lifting velocity control system of the cassava tuber lifting mechanism is studied using the advanced method and technology which has important significance to improve the control precision of the cassava tuber lifting velocity and the harvesting quality of the cassava tubers. The broken and loss rate of the cassava tubers are larger in the cassava tuber harvesting when the control precision of the tuber lifting velocity of the dig-pull cassava harvester is low. Firstly, the co-simulation model of the control system of the tuber lifting mechanism of the dig-pull type cassava tuber harvester was established. The fuzzy PI algorithm was used as the control algorithm of the mechanically optimal tuber lifting velocity of the tuber lifting mechanism. The multi-domain dynamics simulation technology was also used in the co-simulation model. The mechanically optimal lifting velocity model of the cassava tuber was obtained using the cassava tuber lifting tests of the experienced farmers and the optimized velocity model of manually pulling tubers as well as the numerical simulation tests. The mechanically optimal lifting velocity model of the cassava tuber was used as the control target, and meanwhile, the constant cassava tuber lifting force, the cassava tuber lifting force in the soft soil as well as the cassava tuber lifting force in the hard soil, respectively, were used as the condition. The study of the spider clustering algorithm combined with the local search operator was carried out. Then, using a combination of local search operator and spider cluster algorithm, the control parameters of the cassava tuber lifting mechanism system were optimized by iterative optimization. In addition, the common test function was used to verify the convergence and search accuracy of the spider cluster algorithm combined with local search operator. Finally, the cassava tuber lifting test verification was carried out in the field. The error analysis of the verification test was carried out by means of the mean error and the maximum error. The results show that the spider cluster algorithm combined with local search operator which can avoid getting into the local optimal solution in the iterative process, has faster convergence speed and higher search accuracy than the spider clustering algorithm. The spider clustering algorithm combined with the local search operator is suitable for solving the extremum problems of high-dimensional complex function. The optimization result of the Fuzzy PI control system's control parameters: Kp and Ki are 0.841 and 0.203 9, respectively. Using the optimized control parameter, the actual lifting speeds of the cassava tuber can follow mechanically optimal lifting velocity model. And the dynamic performance is great. The average relative error between the actual vertical lifting speed of the cassava tuber and mechanically optimal lifting velocity of the cassava tuber is 4.5%. The maximum error is 6.7%. The average relative error between actual slide displacement and the theoretical value is 3.7%. The maximum error is 5.4%. The spider clustering algorithm combined with local search operator can be used in controlling the cassava tuber lifting process of the dig-pull type cassava tuber harvester. The control precision of the tuber lifting velocity has high precision. [ABSTRACT FROM AUTHOR]