Abstract:Due to the problem of excessive waste accumulation and serious water pollution in traditional feeding mode, high-quality, high-yield and intensive feeding modes for freshwater fish were applied to meet the demand for water products in China, such as industrial aquaculture, containerized aquaculture and pond Juanyang mode. A pneumatic and automatic feeding system was designed, aiming at the problems of high intensity of labour and low degree of automation. The functions of directional, timing and quantitative feeding were realized, combined with Bluetooth control. The main content was summarized as follows: the specific four-way and three-way units were designed to ensure the directional delivery of feed. Based on Computational fluid dynamics-Discrete element method (CFD-DEM) coupling technology, the feeding speed was initially determined, and the fan was selected according to the feeding speed. The feeding system was developed with Arduino Mega 2560 processor;the time and weight information in this system were obtained by clock module and weighting sensor;the data of expected feeding time, feeding weight and feeding area was transmitted through Bluetooth module. Finally, the prototype was performed and tested. For two working conditoins, the error of average feeding distance between experiment and simulation were 5.74% and 9.54%. The directional, timing and quantitative feeding could be achieved accurately, with response time less than 1s. The maximum error of quantified feeding was 5.37%. The results showed that the automatic feeding system can meet the real feeding requirements with reliable structure and high-accuracy control system. This research can provide a solution for the feeding problem of freshwater fish farming.