Development And Implementation Of Cave Drip Sensor And Drip Speed Monitoring And Sampling System

As a country with large population and powerful industry,China’s demand for water resources is increasing,but the pollution of water sources in China is also increasing.Groundwater can be used as fresh water resources.Increasing the rational use of groundwater is the direct way to improve the utilization rate of water resources.In Southwest China,most of them are karst landforms,which are characterized by a large number of rock crevices and caves distributed on the surface,which can not effectively preserve water resources.In addition,the impact of a large number of human activities leads to the shortage of surface water resources.The way of surface water flowing into the ground is complex,and the forms of storage are various.The trace of surface water flow has no fixed rules,so it is difficult to use this part of groundwater resources.The study of groundwater information is of great significance to improve the utilization rate of water resources.In this paper,a kind of cave dripping sensor and dripping speed monitoring and sampling system are designed.It can record the falling time of cave dripping and calculate the dripping speed through the dripping sensor.In addition,the corresponding water samples are collected by mechanical devices.The dripping time and water samples are the basis of studying the groundwater infiltration process in Karst vadose zone.This paper provides a new idea for the design of reliable karst cave drip record collection system,and provides an effective method for the collection of groundwater hydrological characteristicsA multi-layer dripping sensor based on PVDF piezoelectric film is designed.The sensor can sense the free falling body at a distance of more than 15 cm from the sensor.Its working principle is described.With the help of response characteristic analysis and experimental test,the relationship between the size and performance of the sensor element is analyzed,and its size and structure are optimized.Finally,a new dripping sensor is made.A water sample collection device is developed.This device can realize the function of dripping water collection.A total of 25 500 ml bottles of water samples can be collected.Under the condition of minimizing the volume of the device,the water samples can be collected at different times,that is,the bottle changing function of the sampling bottle.The system circuit and its control system are developed,and the upper computer control software and dripping data analysis software are built.The control of dripping sensor and water sample collection device needs to design corresponding circuit for control.This system uses stm32l451 series single chip microcomputer as controller,and sst26vf064 b of microchip is selected for flash,which reduces the power consumption of the system and improves the standby time of the system.The selection of control system scheme is analyzed and studied,such as the monitoring of sudden change of dripping speed.The upper computer control software can monitor,set and debug the operation parameters of the control board through Wi Fi according to the intention of the researchers,while the drip data analysis software can analyze a large number of drip data and detect the reliability of the system.Through the laboratory simulation,field observation application and system function test,the data record analysis shows that the sensor has the advantages of accuracy,stability,water resistance and corrosion resistance,and has been put into field observation application in laohuanglong cave of Kunming City,which can meet the research needs of intelligent drop velocity monitoring.