Research On Multi-source Information Fusion Algorithm Of Combinative Navigation For Paddy Field Operation Machinery

The application of integrated navigation technology in paddy field operation machinery can achieve autonomous walking and precise operation of agricultural machinery.On the one hand,the integrated navigation system composed of Beidou navigation system(BDS)and inertial navigation system(INS)is difficult to meet the accuracy requirement of paddy field operation.On the other hand,the loss of Beidou signal caused by the complex environment of paddy field will also affect the accuracy of navigation positioning.In order to meet the field working machine positioning accuracy,improve the operation efficiency of paddy field,an integrated navigation system based on Beidou Positioning System(BDS),inertial navigation system(INS)and machine vision(VNS)is designed.BDS and INS integrated navigation is adopted to realize the absolute positioning of the paddy field operation machinery.The relative positioning of the paddy field operation machinery is realized by VNS,and the multi-source information fusion algorithm in the system is deeply studied.The main contents of this paper are as follows:(1)Based on the water field environment and the advantages and disadvantages of sensor performance,the positioning performance requirements of the paddy field operation machinery are analyzed,and the overall scheme of BDS/INS/VNS integrated navigation system is determined by the navigation and positioning strategy of the multi source sensor in the paddy field operation machinery.(2)Based on the overall design scheme of BDS/INS/VNS integrated navigation system for paddy field operation machinery,the multi-sensor information fusion algorithm is studied.Because the federated Kalman filtering algorithm has serious filtering divergence,poor convergence effect and low positioning accuracy,an adaptive federal Kalman filtering improvement algorithm is proposed to establish an information fusion model.Firstly,the algorithm constructs the adaptive factor of the subfilter based on the measurement,and secondly according to the relation of variance and weight distribution.The best weight realization algorithm is adaptive to the main filter information distribution.Finally,the simulation experiment of the navigation data is carried out on the standard algorithm and the improved algorithm,and the experimental results are compared and analyzed.It can be seen that the improved algorithm is improved,and the improved filtering algorithm improves the positioning accuracy and meets the requirements of thesystem.(3)According to the overall plan of the integrated navigation system and the functional requirements of the module,a software and hardware system of the corresponding functional module is designed based on the Kubota SPU-68 C,and the Beidou module,the inertial navigation module and the industrial camera are used as the navigation information receiving equipment,the software program of each functional module of the system is designed in the VC++6.0 software environment.(4)Based on the experiment platform design of high speed rice transplanter test platform,the test platform is tested and the information fusion algorithm is verified.The results show that the system can run normally,and the information fusion algorithm can meet the requirements of the operation precision of the paddy field.