Autonomous docking of a tracked wheels robot to its tether cable using a vision-based algorithm

Search and Rescue (SAR) Robotics has been gaining an increasing interest in recent years. In spite of that, there are still many challenges to be addressed in terms of autonomy level. RAPOSA is a semi-autonomous, tracked wheels robot, designed for SAR operations. This paper presents an autonomous docking algorithm. The docking is performed to a docking station that provides both power and a wireless access point. The docking station consists on a small, lightweight pyramidal structure at the end of a flexible cable, allowing the robot to continue operating while attached to this cable. The autonomous docking is mainly based on both vision, whenever possible, and dead reckoning (odometry) that was also developed specially for this work. The results show the effectiveness of the proposed algorithm, even in the presence of difficult environmental conditions.