Jump to : Download | Abstract | Contact | BibTex reference | EndNote reference |

Grabe15a

V. Grabe, H.-H. Bülthoff, D. Scaramuzza, P. Robuffo Giordano. Nonlinear Ego-Motion Estimation from Optical Flow for Online Control of a Quadrotor UAV. The International Journal of Robotics Research, IJRR, 34(8):1114-1135, July 2015.

Download [help]

Download paper: Doi page

Download Hal paper: Hal : Hyper Archive en ligne

Download paper: Adobe portable document (pdf) pdf

Copyright notice:

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. These works may not be reposted without the explicit permission of the copyright holder. This page is automatically generated by bib2html v217, © Inria 2002-2015, Projet Lagadic

Abstract

For the control of unmanned aerial vehicles (UAVs) in GPS-denied environments, cameras have been widely exploited as the main sensory modality for addressing the UAV state estimation problem. However, the use of visual information for ego-motion estimation presents several theoretical and practical difficulties, such as data association, occlusions, and lack of direct metric information when exploiting monocular cameras. In this paper, we address these issues by considering a quadrotor UAV equipped with an onboard monocular camera and an inertial measurement unit (IMU). First, we propose a robust ego-motion estimation algorithm for recovering the UAV scaled linear velocity and angular velocity from optical flow by exploiting the so-called continuous homography constraint in the presence of planar scenes. Then, we address the problem of retrieving the (unknown) metric scale by fusing the visual information with measurements from the onboard IMU. To this end, two different estimation strategies are proposed and critically compared: a first exploiting the classical extended Kalman filter (EKF) formulation, and a second one based on a novel nonlinear estimation framework. The main advantage of the latter scheme lies in the possibility of imposing a desired transient response to the estimation error when the camera moves with a constant acceleration norm with respect to the observed plane. We indeed show that, when compared against the EKF on the same trajectory and sensory data, the nonlinear scheme yields considerably superior performance in terms of convergence rate and predictability of the estimation. The paper is then concluded by an extensive experimental validation, including an onboard closed-loop control of a real quadrotor UAV meant to demonstrate the robustness of our approach in real-world conditions

BibTex Reference

@article{Grabe15a,
   Author = {Grabe, V. and Bülthoff, H.-H. and Scaramuzza, D. and Robuffo Giordano, P.},
   Title = {Nonlinear Ego-Motion Estimation from Optical Flow for Online Control of a Quadrotor UAV},
   Journal = {The International Journal of Robotics Research, IJRR},
   Volume = {    34},
   Number = {8},
   Pages = {1114--1135},
   Month = {July},
   Year = {2015}
}

EndNote Reference [help]

Get EndNote Reference (.ref)

| Lagadic | Map | Team | Publications | Demonstrations |
Irisa - Inria - Copyright 2009 © Lagadic Project