Design And Study Of Velocity Monitoring System Based On Image

In our country, there are numerous rivers, so that water resource comprehensive utilization has an important role in the national economic and social development. From the water conservancy written in No.1 document of central government this year, it can be seen that our country has pay much attention to this area.In our country,because the flood control system is not perfect, there are floodings frequently,these kinds of problems are puzzling ourselves all the time. At the same time, due to the insufficient campacity of water regulation there still has contradiction between supply and demand. The solutions of the problems are depend on the hydrological monitoring information (in a timely and accurate). Velocity measurement is one of the most important works in hydrological monitoring. At present, although there are many methods of velocity measurement, they have limitations in application.In the flood period, there are many sands and some other mishmash in the river,also the speed of the rivers will be fast,and water-stage ups and falls suddenly,so that traditional methods of velocity measurement unable to suit this occasion.On the account of the problems emerged in the velocity measurement, the paper puts forward a new method which makes use of the technology of vedio monitoring to remedy the drawbacks appeared in the traditional float run. This method regards artificial buoys or natural floaters on the river as detecting and tracing targets, adopts principle of solid geometry and photographic surveying, sets up a perspective projection transformation model between amonitoring image coordinate and the actual water surface coordinate, detects targets and traces them accurately, determines the locations of the buoy or floater, in the end measures the velocity. This method uses camera which needn't to touch with the water, so it can avoid clearing the velocity devices regularly.Also, the new velocity monitoring system, after calibration, can real-timely realize velocity acquisition and report, etc.In hardware, the system makes use of TI DSP TMS320DM642 and Sumsung ARM processor S3C2440A, builds up vedio collect module and central control module of the velocity monitoring system, also, achieves the processing results (velocity) remote transimission by GPRS module. In software, the system builds up the software platform of ARM module and DSP module. In software algorithm, combining with the actual environment of velocity (water-stage unsteady), the paper puts forward a new camera calibration method which is simple and feasible.On the account of the river surface in the flooding period, the paper analyzes common target detecting algorithm and target tracking algorithm, presents a target detecting and tracking algorithm for the system, and conducts simulation.Velocity monitoring system based on image can meet the hydrological monitoring conditions in which there often have some characteristics, such as monitoring area wide but point sparse, ruggedsurroundings, unattended, etc. During the flooding period, the system can complete the river regime report to monitoring center. It can provide timely warning, also supply reason for reasonable dispatch, and reduce the harm caused by the flood.