Design And Research On Self-powered Wireless Sensor System Of Asphalt Pavement Based On Piezoelectric Effect

With the development of human society,the highway has become an indispensable part of daily travel.However,road damage caused by overloading,natural weather and geology poses a great threat to the safe driving of vehicles.Therefore,judging the damage of pavement is very important for road construction.It is necessary to recover the pavement performance in an appropriate period and in proper way.However,existing road monitoring solutions require regular maintenance in the sensor system due to battery life limitations.This article studies the information acquisition system using mechanical energy of vehicle pressure conversion into power to supply the energy of the sensor under the road.We propose an end-to-end self-powered wireless sensor(Self-powered Pavement Wireless Sensor,ePave)from the power of the acquisition of information under the road and sent wirelessly to the receiver.This sensor not only solves the problem of battery life,but also uses wireless transmission,which avoids the trouble of deploying the road and further improves the data collection efficiency.The compatibility of road piezoelectric power generation,data acquisition and wireless transmission module is studied.The energy consumption and supply of each part are analyzed,which ensures the effective operation of the system.Finally,the whole system is integrated and embedded in asphalt pavement,and its robustness to road surface is tested.Specifically includes the following aspects:(1)Comparing with the existing pavement detection method,a method of using road piezoelectric energy to drive an ultra-low power sensor and wirelessly transmit pavement data is proposed.The deployment structure and system components of this sensor for self-acquisition of pavement information are designed.(2)A piezoelectric energy harvesting device is designed by the vibration of asphalt pavement.A piezoelectric bimorph is used to convert the mechanical energy of the vibration caused by vehicle into electrical energy.The piezoelectric properties at different pitch depths are studied and the piezoelectric transducer is encapsulated in epoxy resin to increase their lifetime.(3)According to the characteristics of pavement piezoelectric energy,an adaptive data acquisition scheme is proposed to analyze the conversion and power supply mechanism of the pavement piezoelectric energy.The collected data is no longer based on time,but also based on how much energy is collected.Based on the research of the on-time ratio of adaptive switch,the energy utilization efficiency is improved.(4)A self-powered asphalt pavement sensing system prototype is designed.The system is integrated and embedded in asphalt pavement.The performance of the system is evaluated and the wireless information collection of asphalt pavement is realized.Through the system test and result analysis,the system proposed in this paper could work in phase and collect the information of the pavement to the computer terminal,thus realizing the detection of road information.