Vineyard Autonomous Navigation in the Echord++ GRAPE Experiment

Field robotics is a fast developing research field, in particular precision agriculture is gaining in popularity due to the high return in productivity and the reduced pollution impact on the environment. The GRAPE project is an ECHORD++ robotic experiment aimed at the use of a mobile robot for automatic pheromone dispenser distribution in vineyards, to reduce pesticide use thanks to pheromone mate disruption. This work describes the autonomous navigation system of such robot. For the specific scenario a real state of the art does not exists, so we adapted techniques that have been designed for different problems, in particular classical methods for navigation and mapping in indoor environments. The vineyard environment is challenging because of many variability factors such as weather, soil and vegetation. These factors hinder the indoor methods introducing noise in the robot perceptions. To solve this problem, we propose a specific navigation system that takes advantage of multiple sensors: wheel encoders, inertial measurement unit (IMU), and GPS to filter the environment noise and accurately estimate the robot odometry. In addition, the system exploits a LIDAR sensor to localize the robot, through the Adaptive Monte Carlo Localization (AMCL) algorithm, and to map the vineyard. We tested the system in simulation with very good results which have been confirmed during field tests in a real vineyard.