Bearing-only Visual SLAM for Small Unmanned Aerial Vehicles in GPS-denied Environments

• Published in: International journal of automation and computing 2013-10, Vol.10 (5), p.387-396
• Main Authors: Wang, Chao-Lei, Wang, Tian-Miao, Liang, Jian-Hong, Zhang, Yi-Cheng, Zhou, Yi
• Format: Article
• Language: English
• Subjects: Automation; CAE) and Design; Computer Applications; Computer-Aided Engineering (CAD; Control; Engineering; Global Positioning System; GPS; Inertial; Mathematical analysis; Mechatronics; Position (location); Robotics; SLAM; Unmanned aerial vehicles; Vehicles; Visual; 全球定位系统; 小型无人机; 惯性导航系统; 惯性测量单元; 环境; 视觉测量
• ISSN: 1476-8186; 1751-8520
• DOI: 10.1007/s11633-013-0735-8

This paper presents a hierarchical simultaneous localization and mapping（SLAM） system for a small unmanned aerial vehicle（UAV） using the output of an inertial measurement unit（IMU） and the bearing-only observations from an onboard monocular camera.A homography based approach is used to calculate the motion of the vehicle in 6 degrees of freedom by image feature match.This visual measurement is fused with the inertial outputs by an indirect extended Kalman filter（EKF） for attitude and velocity estimation.Then,another EKF is employed to estimate the position of the vehicle and the locations of the features in the map.Both simulations and experiments are carried out to test the performance of the proposed system.The result of the comparison with the referential global positioning system/inertial navigation system（GPS/INS） navigation indicates that the proposed SLAM can provide reliable and stable state estimation for small UAVs in GPS-denied environments.