To reduce the beam structure quality and mass/inertia of high-layer leather cutting machine,and to improve its structural rigidity,an integrated optimization design method that combined system modeling,structure simulation,response surface model with multi-objective optimization was proposed.By using orthogonal experiment,the response surface model for beam structure was constructed to obtain the approximate model.A multi-objective searching method based on Non-dominated Sorting Genetic Algorithm (NSGA-Ⅱ) was adopted to generate Pareto optimal solution sets.As evidenced in the simulation,the proposed method could effectively find design solutions for improving all the conflicting objectives,and had practical value for increasing dynamic performance and reducing energy consumption for high-speed leather cutting machine.

According to urgent need for high speed leather cutting machine,three-ring PID control strategy of servo system is proposed,the mathematical model of servo feed system is built and the simulation block diagram of control system is created based on Simulink.Settle time and ISE performance index are taken as optimal objectives,overshoot and the peak value of controller's output are taken as constraints,to build muli-objective optimization model of speed PI controller.In iSIGHT environment,NSGA-II is chosen to solve the optimization problem,and to get optimal solution according to the sorting of Pareto optimal solution set.The optimization result is compared with traditional genetic algorithm,showing that the dynamic characteristics are more superior by multi-objective optimization method.It has engineering practical value for further improving the leather cutting speed.

In machining process of advanced leather cutting machine,absorbent strength should be determined according to adsorption requirement of leather,so it is necessary to explore factors influencing vacuum absorption force.Leather cutting force is the important factor on adsorption force.The factors affecting leather cutting force were analyzed.The mathematical model of the leather cutting force was established.It was proposed the main method to make blade sharp was to reduce the blade cutting angle.By using theoretical mechanics theory,through moment balance,the mathematical model of the leather absorption force was established.It provides theory foundation for design of different cutting machines.

针对皮革数控裁剪机真空吸附中风机恒速运转存在较大能耗浪费的问题,提出了基于变频控制的真空腔内压实时控制策略。设计了模糊神经网络控制器,根据裁割压力需要,实时改变风机转速,实现对真空腔内压强的实时控制。使用MATLAB语言设计控制器,在SIMULINK上对裁剪机真空吸附控制系统进行仿真,结果表明模糊神经网络控制器能较好完成裁剪机真空吸附控制任务。

To solve the combinatorial explosion problem in Assembly Sequence Planning(ASP) of complex product,Particle Swarm Optimization(PSO) algorithm was applied.Based on the correlation function in extension set theory,an assembly correlation function was proposed to construct assembly connection function combined with various difficult or easy degree of assembly.The electrode module of Light Emitting Diode(LED) sorting machine was taking as the example to show the correlation function's calculation method.Then,taking assembly connection function,assembly feasibility and assembly stability as the evaluation standards,the multi-objective planning model was set up.By using this method,the ASP of LED sorting machine was conducted by integer coding.Comparision between PSO and Genetic Algorithm(GA) was provided,and results demonstrated the superiority of PSO algorithm.

As to the low dynamic response of tangential follow system, especially the poor dynamic follow ability when executing small arc rapid interpolation. Based on the principle of mechanical dynamics, the mathematical model of leather cutting machine tangential follow mechanical transmission system is built, considering a type of high-speed numerical control leather cutting machine as the research object. Joined mechanical model and servo motor model together, its electromechanical combined system diagram is created by Simulink. On the basis of this diagram, the dynamic characteristic is analyzed. The composite evaluation standard including multiple performance indexes is used for the fitness function, the three-ring PID control parameters of tangential follow system is optimized with genetic algorithm (GA). The results show that GA optimization is more superior and efficient, comparing with traditional PID setting method.