The control system design of automatic weeding robot based on visual navigation

Abstract

Aimming at the problem of weeding robot has a bigger radius when changing lines in paddy fields. A novel system of weeding robot based on visual navigation was proposed. Firstly, a special and compact mechanical structure of weeding robot is designed. Secondly, to control the weeding robot automatic navigation, motion control and motors driver board and realtime video capture board respectively were designed. The visual navigation algorithm implemented in TI SOC DM6446 on the video capture module. When video capture is completed, the attitude parameters of seedling centerlines were calculated and detected based on the color model and the nearest neighbor algorithm of clustering combined with Hough transform. Finally, according to the parameters, weeding robot was driven to walk along line corps and cut off weeds with the crawler mobile mechanism in stamping mode. When arriving at the end of raw crops, the weeding robot adjusts the supporting device and striding device to fulfill automatic change lines. Nonholonomic equation with parameter uncertainty was applied to the problem of robot motion control system during the navigation process. The effectiveness of the proposed approach was validated by paddy field tests according to the proposed system. And the results show that weeding robot can correctly achieve line-changed action and meets fast, accurate weeding job requirements.