| With the continuous improvement of people’s living standards,the market demand for crab products increased year by year,the crab industry has become the pillar industry in freshwater aquaculture in China.Aquatic plants cleaning and uniform feeding are two main problems in river crab culture.At present,the river crab culture mainly depends on manpower,the operation route is random and the level of automation is low,which limit the further improvement of benefits.In this paper,a multifunctional automatic aquaculture operation boat based on embedded technology,full coverage path planning technology and boat automatic navigation control technology is designed to complete aquatic plants cleaning and uniform feeding scientifically and efficiently.The main contents and achievements of this paper are as follows:A.A paddle-driven aquaculture operation boat is designed.The hull,paddle,aquatic plants cleaning device,uniform feeding device and other main components are introduced.After analyzing the structure of the control system,this paper introduces the principles of the three kinds of operation modes like manual mode,remote control mode and automatic navigation mode.B.A full coverage path planning algorithm of the aquiculture operation boat is designed.The principle of Gauss-Kruger coordinate transformation and the method of establishing the coordinate system of crab pond working area are introduced.Besides,this paper deduces the calculation formula of the target path for the inner spiral traversal method and the round-trip traversal method,and compares the advantages and disadvantages of the two methods through the simulation experiments.C.An automatic navigation system of the aquiculture operation boat is designed.This paper introduces the high precision RTK-GPS positioning system based on BD982 receiver and the automatic navigation control principle of the boat.According to the motion characteristics of paddle-driven boat like under damping,nonlinear and large time delay,this paper proposes the course/speed double closed loop control algorithm based on fuzzy PID,and then introduces the principle and the decoupling method of course and speed closed loop respectively.In order to avoid the deviation from the target path,this paper proposes the target path interpolation algorithm,the corresponding path switching and the speed strategy.D.The embedded system software of the aquiculture operation boat is designed.This paper builds the cross-compiler software development environment and introduces the porting process of U-Boot and Linux operation system.After that,this paper completes the GUI application with Qt Creator integrated development environment.According to the demand analysis,the GUI application is divided into four modules,which are data acquisition module,data processing module,output control module,data display and interactive module.A system test was carried out and the results showed that each functional module could work normally,the boat responded rapidly and the maximal error at straight and turning path were 0.09 m and 0.36 m respectively.This system can meet the precision requirements of automatic aquatic plants cleaning and uniform feeding in crab pond. |
