Robot Operating System based Charging Pad Detection for Multirotors

The objective of this paper is to develop a wireless charging pad detection mechanism for autonomous quadrotors using AprilTag, and analyze its performance. It uses a Raspberry pi 3B+ single board for data processing and Microsoft webcam for image acquisition and Robot Operating System (ROS) framework and PIXHAWK series flight controller. The charging pad has an AprilTag marker on its top, the camera captures the image and gives it to the ROS node to get the relative position between the camera and charging pad. The system can detect the charging pad at moderate altitudes with a limited number of false detections and give the relative coordinates. An increase in tag size causes an increase in the detection range. The system is compatible with any Single Board Computers (SBC) and cameras. This method is mainly for detecting wireless charging pad to charge quadrotor without human involvement.