Asymptotic moving object tracking with trajectory tracking extension: A homography-based approach

In this paper, a homography-based visual servo controller is developed for a rigid body to track a moving object in three-dimensional space with a fixed relative pose. Specifically, a monocular camera is mounted on the rigid body, and the desired relative pose is expressed by a pre-recorded reference image. Homography is exploited to obtain the orientation and scaled position for controller design. Considering the unknown moving object's velocities and distance information, a continuous nonlinear visual controller is developed using the robust integral of the signum of the error methodology. To facilitate the stability analysis, the system uncertainties regarding the moving object's velocities and distance information are divided into the error-unrelated system uncertainties and the error-related system uncertainties. After that, the upper bounds of the error-related system uncertainties are derived with composited system errors. An asymptotic tracking of the leading object is proved based on the Lyapunov methods and the derived upper bounds. In addition, the proposed controller is extended to address the trajectory tracking problem. Simulation results validate the effectiveness of the proposed approach. Copyright (c) 2017 John Wiley & Sons, Ltd.