Tesis doctoral de Guillem Alenya Ribas
This thesis deals with the motion estimation of a mobile robot from changes in the images acquired by a camera mounted on the robot itself. The motion is deduced with an algorithm previously proposed in the framework of qualitative navigation. In order to employ this algorithm in real situations, a study of its accuracy has been performed. Moreover, relationships with the active vision paradigm have been analyzed, leading to an increase in its applicability. when perspective effects are not significant, two views of a scene are related by an affine transformation (or affinity), that it is usually computed from point correspondences. In this thesis we explore an alternative and at the same time complementary approach, using the contour of an object modeled by means of an active contour. The framework is the following: when the robot moves, the projection of the object in the image changes and the active contour adapts conveniently to it; from the deformation of this contour, expressed in shape space, the robot egomotion can be extracted up to a scale factor. Active contours are characterized by the speed of their extraction and their robustness to partial occlusions. Moreover, a contour is easy to find even in poorly textured scenes, where often it is difficult to find point features and their correspondences. the goal of the first part of this work is to characterize the accuracy and the uncertainty in the motion estimation. Some practical experiences are carried out to evaluate the accuracy, showing the potentiality of the algorithm in real environments and with different robots. We have studied also the epipolar geometry relating two views of a planar object. We prove that the affine epipolar direction between two images can be recovered from a shape vector when the camera motion is free of cyclorotation. With a battery of simulated as well as real experiments, the epipolar direction allows us to analyze the global accuracy of the affinity in a variety of situat
Datos académicos de la tesis doctoral «Estimacio del moviment de robots mitjanÁ§ant contorns actius«
- Título de la tesis: Estimacio del moviment de robots mitjanÁ§ant contorns actius
- Autor: Guillem Alenya Ribas
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 25/10/2005
Dirección y tribunal
- Director de la tesis
- Carme Torras Genís
- Tribunal
- Presidente del tribunal: alberto Sanfeliu cortes
- norbert Krueger (vocal)
- rí¼diger Dillmann (vocal)
- james Crowlwy (vocal)