A Novel Autonomous Robot for Greenhouse Applications

Abstract

This paper presents a novel agricultural robot for greenhouse applications. In many greenhouses, including the greenhouse used in this work, sets of pipes run along the floor between plant rows. These pipes are components of the greenhouse heating system, and doubles as rails for trolleys used by workers. A flat surface separates the start of each rail set at the greenhouse headland. If a robot is to autonomously drive along plant rows, and also be able to move from one set of rails to the next, it must be able to locomote both on rails and on flat surfaces. This puts requirements on mechanical design and navigation, as the robot must cope with two very different operational environments. The robot presented in this paper has been designed to overcome these challenges and allows for autonomous operation both in open environments and on rails by using only low-cost sensors. The robot is assembled using a modular system created by the authors and tested in a greenhouse during ordinary operation. Using the robot, we map the environment and automatically determine the starting point of each rail in the map. We also show how we are able to identify rails and estimate the robots pose relative to theses using only a low-cost 3D camera. When a rail is located, the robot makes the transition from floor to rail and travels along the row of plants before it moves to the next rail set which it has identified in the map. The robot is used for UV treatment of cucumber plants.