Design And Implementation Of Dam Horizontal Displacement Monitoring System With Passive Sensor

China is a large water conservancy country with a large number of dams.Because of the frequent occurrence of geological disasters and the increase of dam service time,there are more and more potential safety hazards in dams.Therefore,dam safety monitoring plays an increasingly important role,and the state and relevant units are paying more and more attention to the safety of dams.At present,more and more sensors are used as the monitoring means of the dam,and the sensor network mainly consists of wired network and wireless network.However,there are some disadvantages in the two networks,so it is of great significance to develop a new sensor connection bus to make up for the defects of wired and wireless connection.In the current sensor network,the wired connection mode has many wiring,and the sealing is easy to fail;the wireless connection mode has the problems of power failure and wireless signal transmission instability.The purpose of this study is to develop a new type of transmission bus,to solve the problems of the above networking mode.This research system is composed of communication host and several signal acquisition units.Taking the fixed inclinometer as an example,it can also be applied to other sensors.The specific organization mode is that the communication host leads out a wire with good insulation,each signal acquisition unit is equipped with a magnetic ring,the wire passes through the magnetic ring of each signal acquisition unit in turn,then each signal acquisition unit is connected to the bus through the magnetic ring,without direct electrical contact,the signal acquisition unit is not equipped with a power supply,the power supply and signal are coupled through the magnetic circuit,and the field is safe.It is very convenient to install,no need to damage the insulation skin,and there is no hidden danger of insufficient waterproof.The main content of this development is the single line model calculation and experiment of signal and power supply path,the research and design of circuit hardware and the development of single chip computer program.The specific work contents are as follows:(1)According to the design requirements,combined with the knowledge learned,design the macro structure of single line transmission system.Assign specific tasks to each part.(2)Select the appropriate magnetic ring,build and calculate the bus electrical model,and select the appropriate bus drive frequency.(3)According to the calculated electrical parameters,calculate and design the hardware circuit,adjust the hardware parameters,and realize the normal operation of the hardware.(4)According to the need of bus energy and signal transmission,the software of single chip microcomputer is compiled to realize the function of data and power exchange.(5)Develop the software and hardware of data repeater,realize modular networking and data batch transmission.Design the special hand-held setting and reading instrument.(6)Realize the overall system joint commissioning,and make the modification and improvement scheme from the actual application.