Optimization Design Of High-speed Gantry Multi-station Palletizing System

Chemical fiber production is the national pillar industry in China,and the intellectualization of chemical fiber packaging line has become the development trend.Industrial robot is an important role in helping chemical fiber packaging line to become intelligent and flexible.As a typical industrial robot,gantry robot is widely used in welding,palletizing,packaging and other work,becoming an essential part of the intelligent factory.The mechanical structure and operation mode of gantry palletizing robot limit the palletizing efficiency in the process of silk cake palletizing of chemical fiber packaging line.This subject comes from Polyester pre-oriented Yarn Automatic packaging line system.Based on virtual prototype technology,mechanical kinematics simulation,rigid-flexible coupling simulation analysis,modal analysis and multi-objective optimization algorithm,the mechanical structure optimization and control system parameter setting of high-speed gantry palletizing robot are completed in this thesis.The main research contents are as follows:1)The mechanical structure and movement parameters of the gantry palletizing robot were determined,and then a motion model was established to verify the feasibility of the parameters.In this thesis,according to the shortcomings of the mechanical structure of the existing gantry palletizing robot,the mechanical structure of POY high-speed gantry palletizing robot was preliminarily determined.The kinematic simulation of virtual prototype technology was used to verify the motion parameters,which is the basis of the subsequent mechanical structure optimization and control parameter setting.2)Multi-objective optimization design and structural strength check of the mechanical structure of high-speed gantry palletizing robot were completed.In this thesis,finite element analysis was carried out on the condition of maximum stress on the main beam and vertical lifting manipulator.A closed-loop optimization model for lightweight design without reducing structural stiffness was established.Neighborhood Cultivation Genetic Algorithm(NCGA)was used for preliminary multi-objective optimization.Radial basis(RBF)neural network method was used for approximate modeling to obtain the mathematical model,and NCGAAlgorithm was used for final multi-objective optimization.The rigid-flexible coupling motion simulation method was used to check the mechanical structure strength of the main beam and the vertical lifting manipulator.3)The control parameters of high speed gantry palletizing robot were designed with displacement track as tracking target.In this thesis,the control strategy of high-speed gantry palletizing robot is PID controller according to the results of field investigation.The mechanical system simulation software ADAMS and mathematical software MATLAB were used to carry out co-simulation,and the theoretical servo control system was built which was composed of closed-loop PID control with displacement trajectory as the tracking target.In order to quickly set PID parameters,the transfer function model was obtained by system identification,and the initial setting parameters were obtained by closed-loop PID control.According to the stop precision error index,the final tuning of PID parameters of each motion was completed.