Design And Implementation Of Automatic Control System For Bulk Material Receiving And Unloading Hopper Based On Loading Model

With the increase of the total volume of bulk material ship transportation in the world,in order to ensure the continuous,stable and orderly bulk material transportation,higher requirements are put forward for the efficiency of bulk material loading and unloading operation in each port.The main direction of port companies with bulk material transportation as the main business is to carry out the automation transformation of bulk material handling equipment and improve the degree of port automation.Taking the bulk material receiving and unloading hopper as the research object,aiming at the problems existing in the manual loading process of bulk material receiving and unloading hopper,an automatic control system of bulk material receiving and unloading hopper is designed in this thesis.The establishment of bulk material loading model is studied.Taking the bulk material loading model as the core,the automatic loading of bulk material receiving and unloading hopper is realized by means of electrical control.The hardware platform of the system is composed of laser scanner,upper computer,PLC,stepping motor and guidance display screen.The software system includes transportation vehicle identification,positioning and guidance algorithm,bulk material type identification algorithm,gate opening time prediction algorithm and loading alignment position solution algorithm.The main research contents of this thesis are as follows:(1)In view of the problems existing in the loading operation of bulk material receiving and unloading hopper,this thesis analyzes the requirements of the full-automatic control system of bulk material receiving and unloading hopper from three aspects of function,installation and operation,designs the system scheme,and completes the hardware and software design of the system.(2)Combined with the control requirements of bulk material receiving and unloading hopper gate,through the analysis and comparison of asynchronous motor,servo motor and stepping motor from three aspects of structure,working principle and control mode,the stepping motor is selected as the gate driving equipment.At the same time,the stepping motor,PLC and laser scanner are selected.(3)The loading model of bulk materials in the carriage is established.Based on this model,the three functions of bulk material type identification,gate opening time prediction and loading alignment position calculation are realized,and the full-automatic loading control system of bulk material receiving and unloading funnel is realized.(4)A large number of observations and records were made on the loading process of bulk material receiving and unloading hopper.According to the recorded data,classification,statistics and induction were carried out,and the distribution laws of stacking angle and stacking height of corn,soybean and Rapeseed under spatial constraints were obtained.The rule is: in the carriage,the stacking angle of corn pile is between 18.26 ° ～ 20.80 °,the stacking angle of soybean pile is between 22.78 ° ～24.70 °,and the stacking angle of rapeseed pile is between 18.78 ° ～ 19.29 °.Under the same carriage,the same loading position and the same loading time,the height of corn pile is less than that of rapeseed pile and less than that of soybean pile.(5)Based on the principle of balancing the total loading volume and the total operation time,the system analyzes and deduces the constraints,decision variables and objective function by means of mathematical programming,and solves the optimal loading control strategy without sacrificing the operation efficiency.The optimal strategy is: for 780 cm long carriage,the optimal number of loading piles is 5,and the interval between two adjacent piles is 156cm;For 990 cm long carriages,the optimal number of loading piles is 8,and the interval between two adjacent piles is124 cm.(6)The full-automatic control system of bulk material receiving and unloading hopper is tested by means of software simulation and field operation.The results show that the bulk material loading model established in this thesis can correctly distinguish the types of bulk materials,accurately predict the opening time of the gate and calculate the loading alignment position.In summary,This thesis successfully completes the design of the automatic control system of the bulk material receiving and unloading hopper,which provides a feasible idea for the realization of the automation of the bulk material receiving and unloading hopper.