A Multi-Binocular Camera-based Localization Method for Amphibious Spherical Robots

This paper presents a novel multi-binocular camera based localization method with panoramic view and high precision for amphibious spherical robots. In our previous work, the proposed approach based on RGB-D camera and inertial measurement unit (IMU) realized a cooperative and relatively close-range localization. While, position drifts caused by the rotation movement and short positioning range of RGB-D camera in underwater environments are the drawbacks of the previous approach. This paper designs a multi-binocular camera system on the amphibious spherical robot, which makes the robot observe targets in a nearly 360-degree visual range without rotation movement. Meanwhile, through the stereo vision model, the robot obtains the position information about the target robot. Then, according to the position information and the relative position of the binocular cameras, the cooperative localization model is established. To validate the proposed approach, experiments were performed in gazebo simulator with varying distances and relative degree. Compared with the previous works, the proposed localization method reveals higher accuracy and robustness.