Design And Test Of Broccoli Harvesting Device

With the continuous improvement of people's food security concerns,a growing number of green vegetables put on the table.Broccoli is rich in vitamin C,folic acid,minerals,as well as anti-cancer and ascorbic acid effects,and is popular among consumers.In recent years,the planting area of broccoli in our country has been increasing year by year,and the harvest of broccoli still depends on artificial labor,which seriously restricts the development of China's broccoli industry.In this paper,broccoli harvesting is the research object.For the current Broccoli harvesting operations in China rely on manual harvesting,which has the problems of high production cost,high labor intensity and low operating efficiency.According to the agronomic requirements of broccoli harvesting,a broccoli-harvesting device capable of selective harvesting and satisfying the agronomic requirements of harvesting was designed.Perform kinematics modeling and parameter optimization of relevant mechanisms,establish virtual prototype simulations and perform harvesting tests.The main research contents of this paper are as follows:1)By reading relevant literature and field investigations,the biological characteristics and agronomic requirements of "Tailv No.3" broccoli was clarified,and the statistical analysis of the appearance size of flower ball were completed.A cutting test bench studied the mechanical characteristics of broccoli stems.The force of the cutter when cutting broccoli stems with different cutting angles were measured,which provided relevant basis for the design of subsequent end-effectors.2)The harvesting mode of broccoli was clarified,the overall design of broccoli harvesting device was proposed,and the design of positioning mechanism,lifting mechanism and end effector in the harvesting device was determined.The kinematics modeling of the lifting mechanism and end effector,and the parameter optimization was completed through the genetic algorithm toolbox in MATLAB.The kinematic characteristics of the optimized mechanism also studied.3)Completed the structural design of the broccoli-harvesting device,performed 3D solid modeling and built a virtual prototype.At the same time,the kinematics simulation of the relevant mechanism was performed.The simulation results were consistent with the theoretical calculations,which verified the correctness of the structural design of the broccoli-picking device.4)Complete the analysis of the operation sequence of the harvesting device,and write the control program with PLC as the core of the control system.In addition,the control interface designed by Lab View2016 software,and the Communication between PLC and host computer is realized through MX Component plug-in.5)Completed the assembly and debugging of the harvesting device and the simulated picking test bench,and carried out the no-load operation and physical harvesting test of the harvesting device.The test results show that the Broccoli harvesting device designed in this paper can complete the harvest of broccoli.In addition,the effect of broccoli harvesting device on broccoli with different stem diameters(Cylinder theoretical output force)under different air pressure conditions was investigated.