Visual odometry system performance for different landmark average distances

In this paper, we present an experimental analysis of how landmark distributions in a scene, as observed by a stereo-camera, affect Visual Odometry measurement performances. Translational and rotational tests have been performed in many different positions in an indoor environment. The Visual Odometry algorithm, which has been implemented firstly, guesses motion by a linear 3D-to-3D method embedded within a RANdom SAmple Consensus (RANSAC) process to remove outliers. Then, motion estimation is computed from the inliers by minimizing the L
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distance between the triangulated landmarks. The ground truth is given by mounting the stereo camera both on a high precision motor-driven rotary stage and on a linear slide. Experimental results show that the landmark's average distance affects the rotation and translation reconstruction in two different ways: for translations, the uncertainty of camera position grows with the landmarks distance; yet, for rotations, landmark distances have no effect on rotation uncertainty.