Design and Experiment of Intelligent Picking Robot for Famous Tea

doi:10.3901/JME.2022.19.012

Abstract

Abstract: In view of the current situation of labor force shortage in famous tea picking, this paper designs a robot for famous tea picking, which is suitable for natural environment. The robot is composed of picking module, 3P-Delta manipulator, vision system and controlling system. The robot captures the image of tea canopy using RGB-D camera, and then calculates the picking points by deep learning model and the skeleton method. Based on the growth characteristics of famous tea, the picking trajectory model of the manipulator was established. The Bézier curve was used to optimize the picking path of tea, which effectively alleviated the acceleration mutation caused by the rapid motion of the manipulator and improved the smoothness of the picking movement. The dynamic model of the manipulator was established by using the principle of virtual work, and the picking control algorithm of the manipulator is designed based sliding surface variable structure control. The exponential reaching law in the control algorithm is optimized, so that the chattering phenomenon in the sliding surface control is effectively suppressed in the process of rapid reaching. The field test results show that the picking robot can realize the picking of famous tea in the natural environment, and the picking rate and integrity rate are 75.53% and 54.68%, respectively. The average picking speed of the robot is 0.451/s.

Key words: picking robot, famous tea, 3P-Delta manipulator, Bézier curve, sliding mode control, system integration

CLC Number:

ZHOU Yujie, WU Qiang, HE Leiying, ZHAO Runmao, JIA Jiangming, CHEN Jianneng, WU Chuanyu. Design and Experiment of Intelligent Picking Robot for Famous Tea[J]. Journal of Mechanical Engineering, 2022, 58(19): 12-23.

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