Closed Loop Control Technology Of Fire-fighting Monitor Based On Video

Fire-fighting monitor automatic positioning technology is an effective way to put out the fire in large spaces.However,most of the automatic positioning fire-fighting monitors are using open loop control technology.Because of water pressure,wind or other factors,the fall point of the fire-fighting monitor is prone to offset so that the fire-fighting monitor is unable to accurately hit the fire point to eliminate the fire.Closed loop control technology of fire-fighting monitor based on video can adjust the angle automatically according to the deviation between the fall point and the fire point in order to put out the fire.In this thesis,closed loop control algorithm of fire-fighting monitor based on video is researched under the background of large space intelligent fire extinguishing system.In this thesis,an algorithm is proposed to realize closed loop control of the fire-fighting monitor.Firstly,the jet curve is extracted,and then the fall point is calculated according to the color feature of the jet end.Finally,the angle is adjusted according to the physical model of the fire-fighting monitor.Because the scattering in the jet end is obvious and the extraction of the jet region is affected seriously.In this thesis,an algorithm which can solve this problem is proposed.Firstly,the transmission image is extracted using the dark channel prior and is threshold processed.Then,the moving region is extracted using background subtraction based on Gaussian mixture model.Finally,the jet region is obtained by matching.An algorithm which can detect the fall point effectively is proposed.Firstly,the target points of the jet trajectory are gotten by one-way searching.Then,the jet end region is gained by curve fitting using the least square method.Finally,the fall point is identified by naive Bayes classifier according to the color feature of the jet end region.An algorithm which can control the fire-fighting monitor accurately is proposed.At first,the camera is calibrated so that the fall point,the start point and the fire point can be projected to the world coordinate.Secondly,the physical model of the fire-fighting monitor is simulated to get the mapping relationship between the pitching angle and the range.At last,the closed loop control scheme of the pitching angle and the horizontal angle is proposed.The experimental results show that the proposed algorithm can effectively overcome the interference from the scattering of the jet end as well as most of the moving region which has nothing to do with the jet.Even if there is some missing in the jet region,the detection effect won't be affected.In this thesis,the ratio of the algorithm to identify the fall point is high.Although the algorithm in this thesis has high time complexity,through the method that process a frame every few frames,it not only has no effect on accuracy but also meets the requirements of real-time.Finally,accurate control of the fire-fighting monitor's fire extinguishing process is realized.