Research And Implementation Of Video Surveillance System For Liquid Level Based On Embedded System

Liquid level measurement technology plays a very important role in the field of defense technology and industrial production, etc.. Many liquid level measurement methods used before is basically mechanical measurements, as well as the traditional methods have a lot of different disadvantages. More commonly used method like ultrasonic measurements is affected relatively large by liquid surface fluctuation, and costs high. Capacitive level meter only can be used when the measured liquid has a large dielectric constant, but in a complex environment or the required measurement accuracy is relatively high, the traditional methods are usually more difficult to achieve satisfactory results. With the advancement of technology, and the increasing demands on digitalization, miniature-ization, precision and other aspects of measurement systems, many new level measurement methods have been proposed, which combines image processing and image recognition technology, and apply to the detection of liquid level, due to its characteristics with real-time performance and high precision, have been widely applied to industrial production. In this paper, we will combine the embedded technology, image processing technology and visual sensing technology, through the analysis of the advantages and disadvantages of the various existing level measurement system, and design an intelligent liquid level measuring system based on embedded system.This paper presents a smart and high speed level video surveillance system based on collaboration of FPGA and ARM, which will full use of the advantages of real-time and high-speed processing of the FPGA. By FPGA control the analog CMOS camera to capture images of ruler scale, the store in the SDRAM, the images read from SDRAM go through the image pre-processing module and then store in RAMs, again by the master controller ARM9microprocessor reads the image data from RAMs, through image recognition algorithm, we can get the liquid level, finally, the measurement results can be displayed on the LCD. The study will focus on the design of a system including liquid image acquisition, storage, display and image process, eventually achieve the accurate measurement of liquid level. The design includes a stable light source for lighting, improving the quality of the images and the accuracy of the result, and can automatically read the current result in real time, the whole process can be done without human intervention.After a number of experiments, the system can realize the real-time image acquisition, transmission, process and recognition of liquid level image part with scale. Meanwhile the digital character recognition algorithm with high interference resistant and robust, solve the tradition contact measurement problems. This method of liquid level measurement in the reservoir areas, tanks and other aspects have broad application prospects.