Design Of Water Quality Environment Dynamic Monitoring System Based On Unmanned Surface Vessels

Since the ancient times,water is one of an important condition to the survival of people.At the same time,the problem of water pollution is increasingly serious.It is particularly important to detect the water quality of rivers,lakes and breeding areas to find the source of pollution.The existing water quality monitoring devices,such as water quality monitoring stations,buoys,and large water surface detection vessels,have high costs,inflexible detection,limited number of water quality detection areas and some water areas can't be detected,resulting in poor timeliness of water quality detection.Therefore,this paper designs and implements a dynamic monitoring system for water quality environment based on an Unmanned Surface Vessels(USV)device,which can realize the water quality detection of rivers,lakes,narrow waters and breeding areas and the tracking and positioning of pollution sources.This article mainly completes the following work and design:(1)For environmental monitoring,through reforming the existing USV structure,USV hardware design the monitoring system,including power management module,main control chip module,sampling module,wireless communication system module,storage module,water quality monitoring system for sensor module and GPS positioning module,and motor drive module interface,video acquisition system module interface,electronic compass module interface and lidar module interface;And through software design,it realizes autonomous navigation and obstacle avoidance of USV,as well as water quality collection and sampling functions.(2)Based on the diffusion model of pollution source,a method of river pollution source location based on Goldsim simulation algorithm,path tracking algorithm and concentration gradient method is designed.(3)Path tracking algorithm and obstacle avoidance strategy are studied.The nonlinear control rate based on Lyapunov is adopted to make the path following error coordinate converge to zero,so as to realize autonomous navigation and obstacle avoidance of USV,and the heuristic method is used to solve the problem of advance adaptation speed based on path curvature measurement and steering motion prediction.(4)The upper computer interface of USV is designed,including the control direction of USV,water surface image and video,lidar profile,GPS positioning information,hull position and water quality data curve,etc.,which can realize remote monitoring,control and data acquisition.It is proved by experiments that the water quality and environment dynamic monitoring system designed in this paper can realize independent navigation on rivers,track and avoid obstacles through the nonlinear control rate and heuristic method based on Lyapunov,collect and sample water quality data,and track and locate pollution sources.The remote control of USV,the transmission and display of image data and the water quality curve are also realized on the upper computer interface,and the three-dimensional graph of the pollutant concentration of turbidity is drawn based on the turbidity sensor data collected by USV.The experimental results show that the water quality and environment dynamic monitoring system of USV can meet the design requirements and meet the system design indexes,and can be used for continuous monitoring of aquaculture monitoring,rivers,lakes,urban inland rivers and water areas with complex conditions.