Detection Of Road Icing Based On Piezoelectric Resonance Sensor

In the north of China,the roads are usually frozen in winter because of the cold climate.The frozen roads lead to extreme traffic accidents,which has a huge influence on human social life,such as health care and industrial production.Therefore,the significance of road ice detection is particularly important.Due to the existing detection methods of road icing at home and abroad,which have small measuring range and low accuracy,piezoelectric ceramic strain gauge is used to detect road icing in this paper.Firstly,the bending differential equation related to deflection is obtained by solving the geometric equation,physical equation and balance equation.The relationship between resonance frequency and ice thickness of thin plate is calculated by the deflection differential equation and the boundary condition of thin plate during detection.When the sensor surface is covered with ice or water,the stiffness and mass of the sensor will change according to the difference between the two substances.When the sensor surface is covered with water,the resonance frequency will decrease with the increase of the thickness of water accumulation;when the sensor surface is covered with ice,the resonance of the sensor will increase with the increase of the thickness of ice layer.Therefore,through the influence of different states of water on resonance frequency,we can judge whether there is water or ice on the road surface.Ice thickness can be calculated by the added value of resonance frequency.Secondly,according to the actual demand of road icing,the hardware system of road icing detection system is designed,including sensor probe part,signal transfer station system and cloud platform terminal part.The internal control chip of the sensor probe controls the signal generator to generate a variety of positive and negative frequency waves,which are sent to the piezoelectric ceramic vibration plate.The control chip resamples and receives the return signal of the vibrationplate,which is sent to the transit signal station through RS485 communication according to the return signal data.The transit signal station is responsible for data processing and remote communication,which is sent to the cloud platform through GPRS wireless communication module.The cloud platform terminal is a mobile phone or a computer,which is mainly responsible for receiving and displaying the road icing data sent by GPRS module,and observing the road icing condition in real time through remote monitoring,so that the traffic management department can make timely response measures.Finally,the software design and system test of the road ice detection system are completed.It mainly includes the design and debugging of sensor probe data communication,data display,road ice data processing,temperature compensation,correction cloud platform communication and other functional modules.In order to observe the change of data more intuitively,the visual interface is used to draw the curve of ice thickness and the current ambient temperature in real time.Due to the influence of different ambient temperature on the data,it is necessary to calibrate and compensate the collected data to ensure the accuracy of the measurement data.The remote terminal is used to receive the cloud platform data and display the ice state of the road,monitor the ice state of the road in real time,and release the ice warning information in time.