Design And Test Of Control System For Grain Sampler In Warehouse

At present,manual sampling and electric sampler sampling are two commonly used sampling methods in granary in China.The manual sampling operation not only has the problems of low efficiency and poor representativeness of samples,but also the environment is not conducive to long-term operation.The sampling operation of electric sampler relies on multi-person collaboration,and the power supply mode is to drag cables,which is easy to cause safety accidents.In view of the above problems,this paper carries out the design and test of electrical control system on the basis of the prototype machine of grain sampler in warehouse developed by our research group,and realizes the functions of automatic walking,connecting rod changing,speed control sampling and remote monitoring of the sampler,so as to solve the shortcomings of the existing two sampling methods.The main research contents of this paper are as follows:(1)Research on DC speed control sampler.The STAR-CCM + simulation analysis was carried out on the relationship between the grain suction height and the negative pressure,and the design scheme of the DC motor was studied.Through the MATLAB simulation analysis and comparison,the fuzzy PID control algorithm was determined for the simulation analysis of the motor control effect,and the motor control algorithm was determined.The relationship between the motor speed and the grain suction height was studied by setting up the test platform.The results show that the test data can be fitted into the equation,and the maximum grain suction height of the sampler is 7.6 m.(2)Research on the Control System of the Rod changing Mechanism of the Sampler.The working flow of the grain sampling prototype in the warehouse and the action steps of the main electrical components are designed.The Hall proximity switch and the positioning device are used to determine the stop position of the motor.(3)Research on control system of walking mechanism.The force analysis between the track and the grain surface was carried out,and the required traction force and motor torque were calculated according to the self-weight changes of the whole machine under no-load and full load conditions.The duty cycle of the double motors was adjusted according to the bending test of the sampling prototype,and the optimal duty cycle of the motor was determined during the turning.The results show that the traction force is 640 N,and the motor torque is 32 N·m.The optimal duty cycle is(1 / 10,1),(1,1 / 10),(1 / 10,1)and(1,1 / 10)in the front left,front right,back left and back right walking,respectively.(4)Research on remote control and video surveillance scheme based on 5G communication.The CAN bus technology is adopted,the video data were transmitted back to the host computer CPE by 5G communication equipment.The remote control host computer interface was developed to realize the function of real-time remote monitoring of the grain situation in the warehouse.The field simulation test shows that the design meets the requirements of remote control and video monitoring of the grain sampling prototype in the warehouse.