Research On The Strain Monitoring System Of Passive Wireless Conveyor Belt

In recent years,more and more belt conveyor with high speed,heavy load,and long-term continuous working condition been used,as to reduce the running safety of belt conveyor,the matching of drive device,and further increase the probability of failure of belt conveyor.Because tensile wave is exist at the same time,when the conveyor runs at the start or brakes at the end,the start of the pulling force and braking force of conveyor belt is very large.Usually it can be more than dozens of times of tension under stationary state,not only reduce the safety of the conveyer belt and life spans,also easy to cause broken belt and other major safety accidents.It is very typical that the conveyor belt has broken belt accident,especially the conveyor belt of high transportation and large volume.If the belt had broken,it will cause a lot of scattered material at the bottom of the belt conveyor,bring huge workload to conveyor maintenance and repairing,but also affect the coal mine safety in production in a row,and may even cause casualties.But if in the process of start,work and stop above can obtain real-time multi-point distribution of stress and strain parameters of conveyor belt,and combining the theory of fatigue damage accumulation and damage mechanism research,using transfinite machine learning and other intelligent algorithm,effectively predict early damage and damage location of conveyor belt,which can avoid the happening of the accident.In order to achieve the above goal,a passive wireless conveyor belt strain monitoring system is designed.The system consists power self-supply,location along with the way,the strain signal acquisition and wireless transmission of function of flexible strain sensor with a RF power transmission and wireless data receiver of function of the reader.The design process of this system: the theoretical basis of wireless charging are expounded and the parameters of various wireless charging technologies are calculated,and the wireless charging technology scheme is determined.Soft substrate energy collection antenna is designed and simulated,and determining its antenna parameters.Using the antenna parameters of the receiving and transmitting antennas calculate the RF transmitting power and the model of the radiofrequency emission source is determined.The principle and theoretical model of the voltage rectifier circuit are analyzed,and the model of the voltage rectifier circuit is determined.The strain gauge model is determined by power calculation.Complete the entire system workflow construction and major equipment selection.This thesis analyzes the theoretical power of wireless charging,data acquisition,data transmission and other functional requirements,and selects the microprocessor.The AD conversion module and the characteristics of the collected signals in this thesis are further analyzed.The strain sensor analog signal processing circuit is designed using MULTISIM(circuit simulation software).Model of strain gauge is determined by power calculation.The specific parameters of strain sensor are determined by simulating the analog signal processing circuit.Finally,designing and building the circuit board by using ALTIUM DISIGNER.Completing the construction of strain sensor analog circuit.To study the distribution of energy at different times,this thesis design the program of microprocessor control strain sensor unit and collect data plan,so as to ensure the accuracy of collecting data.Designing the data packet transmission topology network and the program flow chart of each node.Through the design idea of flow chart,IAR is used to design the main program.In this case,the construction of transmission topology network is completed.The design experiment scheme verifies the power,control scheme and topology network stability of strain sensor.A strain error test scheme was designed by using a microcomputer controlled electronic universal testing machine.The test data was analyzed and the test error of the strain sensor was calculated.Through the above two experiments,it is proved that the monitoring precision of the passive wireless conveyor belt strain monitoring system meets the industrial demand.