Extended Data Fig. 2: Onboard vision system of FlyingToolbox.
From: Proximal cooperative aerial manipulation with vertically stacked drones
a. The design of the onboard vision system involves six steps: three offline steps (QR code array design, camera calibration, and hand-eye calibration) and three online steps (QR code detection, 6D pose estimation, and filtering at 50 Hz). b. Offline hand-eye calibration was performed using a motion capture system to determine the transformation between the camera frame and the manipulator MAV base frame. The two manipulator MAVs are equipped with an Intel RealSense L515 camera and a D435i camera, respectively, both operating at 640 × 480 pixel resolution. c. The onboard camera can detect a subset of the QR codes during aerial docking. d. The vision system achieves an average positioning error of 0.48 cm with a standard deviation of 0.12 cm when the vertical distance between the manipulator MAV and the toolbox MAV is 0.6 m.
