Design and Modelling of Cable Suspended Sonde for Water Quality Monitoring

Quality of water bodies is measured for environmental monitoring, irrigation and potable water. The depth of water bodies like river, lake, well and pond, varies between 3m to 10m. In the recommended system, water qualities, namely, pH, turbidity and temperature are logged automatically from a floating platform and the data is transmitted to the shore for further analysis. The sensor box is suspended by a cable from the floating platform and an automatic winch mechanism is used for lowering the box for vertical profiling. Two Arduino microcontrollers are used for data collection, wireless transmission and winch control. Mathematical modelling of displacement of the sensor box due to flow is done using fluid dynamic equations. Depth of the sensor box is obtained from the ultrasound sensors. Communication from the sensor box to the platform is done through serial interface and the data is transmitted from the platform to the shore via bidirectional WiFi. The system is capable of measuring, logging and profiling water quality at different locations and providing it in near real time for assessing environmental impact.