Study On The Key Technology Of Three Dimensional Fast-driven Tea Picking Machine

Tea fresh leaves picking is an important part of tea production and it determines the merits of tea product.As a labor-intensive industry,the tea picking industry has been faced with increasing pressure because of the increase in labor costs.Although there are tea picking machines based on the shear principle in use,these machines applies only to bulk tea picking for lack of selectivity.Therefore,the research project is set up for the needs of high-quality tea selective picking.This project mainly solves the three-dimensional positioning problem during the process of tea picking.The main points and research results of this paper are shown as follows:(1)The extraction of tea picking coordinates and path optimization.Based on the tea shoots image information,extracted the tea picking two dimensional coordinates with monocular vision technology and image processing technology.The tea picking coordinate in the vertical direction is determined in the positioning process,a groove photoelectric sensor mounted on the vertical drive mechanism is applied to detect the real-time position.An optimization algorithm combined greedy algorithm and simulated annealing algorithm was proposed to solve the optimization of tea picking path based on the initial obtained coordinates.(2)The design of tea picking three-dimensional fast-driven system.According to the positioning accuracy and positioning speed requirements,designed a three-dimensional positioning device based on the ball screw pair to achieve the positioning function during the tea picking process.The ball screw linear modules were used to achieve two-dimensional coordinate positioning;the acme thread lead screw was used as the vertical positioning mechanism duo to the small stroke.The Siemens drive-based controller Simotion D425-2DP/PN was adapted as the hardware platform.The related control procedures were written with ST and MCC programming languages to achieve motion control and logic control in the Siemens Simotion Scout software system.In addition,the WinCC flexible configuration software wasused to create the human machine interface in order to debug the device and monitor the status of the system conveniently.(3)The overall planning of selective tea picking and the simulation of tea picking three-dimensional positioning.The process and implementation method of selective tea picking were analyzed.The validity of the optimization algorithm and the positioning accuracy of the positioning system were illustrated by the example of three samples.The average optimization ratio of the optimization algorithm with respect to the greedy algorithm and simulated annealing algorithm is 6.3 present and39.9 present respectively when taken the length of path as the evaluation index.By measuring and analyzing the sample positioning data,the maximum positioning error of the positioning system is 0.206 millimeter and the average error is 0.137 millimeter.