Détection et suivi d'objets mobiles perçus depuis un capteur visuel embarqué

Dora Luz Almanza-Ojeda 1
1 LAAS-RAP - Équipe Robotique, Action et Perception
LAAS - Laboratoire d'analyse et d'architecture des systèmes [Toulouse]
Abstract : This dissertation concerns the detection and the tracking of mobile objets in a dynamic environment, using a camera embedded on a mobile robot. It is an important challenge because only a single camera is used to solve the problem.We must detect mobile objects in the scene, analyzing their apparent motions on images, excluding the motion caused by the ego-motion of the camera. First it is proposed a spatio-remporal analysis of the image sequence based on the sparse optical flow. The a contrario clustering method provides the grouping of dynamic points, without using a priori information and without parameter tuning. This method success is based on the accretion of sufficient information on positions and velocities of these points. We call tracking time, the time required in order to acquire images analyzed to provide the points characterization. A probabilistic map is built in order to find image areas with the higher probabilities to find a mobile objet ; this map allows an active selection of new points close the previously detected mobile regions, making larger these regions. In a second step, it is proposed an iterative approach to perform the detection-clustering-tracking process on image sequences acquired from a fixed camera for indoor or outdoor applications. An object is described by an active contour, updated so that the initial object model remains inside the contour. Finally it is presented experimental results obtained on images acquired from a camera embedded on a mobile robot navigating in outdoor environments with rigid or non rigid mobile objects ; it is shown that the method works to detect obstacles during the navigation in a priori unknown environments, first with a weak speed, then with more a realistic speed, compensating the robot ego-motion in images.
Document type :
Theses
Complete list of metadatas

Cited literature [93 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01017785
Contributor : Arlette Evrard <>
Submitted on : Thursday, July 3, 2014 - 10:46:12 AM
Last modification on : Friday, June 14, 2019 - 6:31:04 PM
Long-term archiving on : Tuesday, October 13, 2015 - 3:20:35 PM

Identifiers

  • HAL Id : tel-01017785, version 1

Citation

Dora Luz Almanza-Ojeda. Détection et suivi d'objets mobiles perçus depuis un capteur visuel embarqué. Robotique [cs.RO]. Université Paul Sabatier - Toulouse III, 2011. Français. ⟨tel-01017785⟩

Share

Metrics

Record views

1466

Files downloads

23172