Development and Initial Evaluation of a Multi-Purpose Spraying Robot Prototype

We present a versatile mobile robotic sprayer system, primarily aimed for pesticide application in greenhouses and for disinfection of indoor spaces. The prototype is built around a skid-steered wheeled platform driven by a pair of DC motors, and is equipped with an electronically controlled sprayer unit that is mounted on a pan/tilt robot arm for directing the spray. The robot can be operated either manually or in AGV mode, utilizing a magnetic guide sensor to track a predefined path, along with a depth camera and ultrasonic sensors for obstacle detection. The robot's control architecture employs a central Single Board Computer running ROS, with peripheral functions allocated to three 8-bit microcontrollers. Closed loop flow regulation schemes have been developed to provide precision variable application rate of the sprayed agents, combined with motion control strategies of the pan/tilt unit to implement rectangular coverage spraying. The robot's capabilities are demonstrated through a series of tests, involving laboratory experiments as well as application scenarios trials.