Development Of The Machine Vision-based Liquid Level Detection System

Under the background of made in China 2025,the household appliances industry is transforming and upgrading to digitalization,informatization and intellectualization.added are functions of automatically supplying water to a cup and stopping water supply when a cup is full which is give the water dispenser intellectualization and provide a more convenient way to intake water.The design can adapt to the water intake cup of transparent and non-transparent materials between 75 mm and 150 mm.The main research contents of this paper are as follows:1.The author learned feasible solutions after investigating the researches on liquid level detection system at home and abroad,and designed water level detection system for cup according to the functional requirements and related indicators.The design includes the selection of hardware such as image acquisition device,lighting scheme and operation processor,and the overall construction of the experimental platform for water level detection system for cup.2.Based on the key technology used in the machine vision-based liquid level detection system,the author studies the system algorithms designed for the following four purposes: to extract information on the cup position,to detect the placement of a cup,to extract characteristics of liquid surface and detecting liquid level,and to control process.To extract information on the cup position,the author discusses image filtering,edge detection,Hough transformation and its improved algorithms.To detect the placement of a cup,the author proposes a solution that combines frame difference with background difference so that self-adaptive background upgrading can be achieved to better adapt environment.To extract liquid surface characteristics,the background difference method and the histogram equalization are applied to enhance the contrast of the liquid surface,they are employed to extract liquid surface features.To make the water dispenser switch between adding water and stopping adding water according to the current liquid level control,the author proposes liquid level detection and switch control algorithms based on the different characteristics of adding watering state and water-stopping state.3.The author describes overall design of the liquid level detection system of water dispenser,and analyzes the hardware and software structure of the system.By testing six typical intake cups,which are high,medium,low,transparent and opaque,the experimental results of each part of the software are observed and the system performance and adaptability are analyzed.The experimental results show that the liquid level detection device designed in this paper can be adapted to the detection of common intake cups,and has high application value.The level detection system described in this paper innovatively applies machine vision technology to the level detection system of water dispenser platform.By processing the image collected by image sensor with each step algorithm,the level height information can be obtained,and then the opening and stopping state of water dispenser can be controlled.After theoretical analysis,the feasibility of liquid level detection system is verified by experiments.The innovative application of machine vision technology in water intake cup level detection of water dispenser endows the water dispenser with intelligence and redefines the functions of the new generation of water dispenser.