Robotic weed control using machine vision

The purpose of this work is to present a non-chemical weed controller for vegetable crops derived from a cooperative French-Spanish project. One of the major efforts of this project is related with working in a natural, complex environment and the similarity between the weeds and the vegetable crop, which makes locating the weeds difficult. The robotic arm presents a parallel structure with six degrees of freedom, and due to its light structure, it is capable of reaching high accelerations. The end-effector has an electrode powered by a set of batteries and kills the weeds by producing an electrical discharge of 15 000 V. All the subsystems of the machine communicate through a controller area network (CAN) bus. There are two vision systems mounted on the machine. The first one is placed at the front of the robot to acquire and analyse field images, in order to detect weeds and send their coordinates to the robotic arm control. The second camera is placed close to the electrode, and its mission is to correct inertial perturbations by relocating every individual weed detected by the first vision system. The successful performance of this new concept of precise non-chemical weeding has been demonstrated in a lettuce crop in Valencia, Spain. (C) 2001 Silsoe Research Institute. Published by Elsevier Science Ltd. All rights reserved.