2,045 research outputs found
Simultaneous Parameter Calibration, Localization, and Mapping
The calibration parameters of a mobile robot play a substantial role in navigation tasks. Often these parameters are subject to variations that depend either on changes in the environment or on the load of the robot. In this paper, we propose an approach to simultaneously estimate a map of the environment, the position of the on-board sensors of the robot, and its kinematic parameters. Our method requires no prior knowledge about the environment and relies only on a rough initial guess of the parameters of the platform. The proposed approach estimates the parameters online and it is able to adapt to non-stationary changes of the configuration. We tested our approach in simulated environments and on a wide range of real-world data using different types of robotic platforms. (C) 2012 Taylor & Francis and The Robotics Society of Japa
3D modeling of indoor environments by a mobile platform with a laser scanner and panoramic camera
One major challenge of 3DTV is content acquisition. Here, we present a method to acquire a realistic, visually convincing D model of indoor environments based on a mobile platform that is equipped with a laser range scanner and a panoramic camera. The data of the 2D laser scans are used to solve the simultaneous lo- calization and mapping problem and to extract walls. Textures for walls and floor are built from the images of a calibrated panoramic camera. Multiresolution blending is used to hide seams in the gen- erated textures. The scene is further enriched by 3D-geometry cal- culated from a graph cut stereo technique. We present experimental results from a moderately large real environment.
Multi sensor fusion of camera and 3D laser range finder for object recognition
Proceedings of: 2010 IEEE Conference on Multisensor Fusion and Integration for Intelligent Systems (MFI), September 5-7, 2010, Salt Lake City, USAThis paper proposes multi sensor fusion based
on an effective calibration method for a perception system
designed for mobile robots and intended for later object
recognition. The perception system consists of a camera and a three-dimensional laser range finder. The three-dimensional
laser range finder is based on a two-dimensional laser scanner
and a pan-tilt unit as a moving platform. The calibration
permits the coalescence of the two most important sensors
for three-dimensional environment perception, namely a laser
scanner and a camera. Both sensors permit multi sensor fusion
consisting of color and depth information. The calibration
process based upon a specific calibration pattern is used to
define the extrinsic parameters and calculate the transformation
between a laser range finder and a camera. The
found transformation assigns an exact position and the color
information to each point of the surroundings. As a result, the
advantages of both sensors can be combined.
The resulting structure consists of colored unorganized point
clouds. The achieved results can be visualized with OpenGL
and used for surface reconstruction. This way, typical robotic tasks like object recognition, grasp calculation or handling of
objects can be realized. The results of our experiments are presented in this paper.European Community's Seventh Framework Progra
Real-Time fusion of visual images and laser data images for safe navigation in outdoor environments
[EN]In recent years, two dimensional laser range finders mounted on vehicles is becoming a
fruitful solution to achieve safety and environment recognition requirements (Keicher &
Seufert, 2000), (Stentz et al., 2002), (DARPA, 2007). They provide real-time accurate range
measurements in large angular fields at a fixed height above the ground plane, and enable
robots and vehicles to perform more confidently a variety of tasks by fusing images from
visual cameras with range data (Baltzakis et al., 2003). Lasers have normally been used in
industrial surveillance applications to detect unexpected objects and persons in indoor
environments. In the last decade, laser range finder are moving from indoor to outdoor rural
and urban applications for 3D imaging (Yokota et al., 2004), vehicle guidance (Barawid et
al., 2007), autonomous navigation (Garcia-PĂ©rez et al., 2008), and objects recognition and
classification (Lee & Ehsani, 2008), (Edan & Kondo, 2009), (Katz et al., 2010). Unlike
industrial applications, which deal with simple, repetitive and well-defined objects, cameralaser
systems on board off-road vehicles require advanced real-time techniques and
algorithms to deal with dynamic unexpected objects. Natural environments are complex
and loosely structured with great differences among consecutive scenes and scenarios.
Vision systems still present severe drawbacks, caused by lighting variability that depends
on unpredictable weather conditions. Camera-laser objects feature fusion and classification
is still a challenge within the paradigm of artificial perception and mobile robotics in
outdoor environments with the presence of dust, dirty, rain, and extreme temperature and
humidity. Real time relevant objects perception, task driven, is a main issue for subsequent
actions decision in safe unmanned navigation. In comparison with industrial automation
systems, the precision required in objects location is usually low, as it is the speed of most
rural vehicles that operate in bounded and low structured outdoor environments.
To this aim, current work is focused on the development of algorithms and strategies for
fusing 2D laser data and visual images, to accomplish real-time detection and classification
of unexpected objects close to the vehicle, to guarantee safe navigation. Next, class
information can be integrated within the global navigation architecture, in control modules,
such as, stop, obstacle avoidance, tracking or mapping.Section 2 includes a description of the commercial vehicle, robot-tractor DEDALO and the
vision systems on board. Section 3 addresses some drawbacks in outdoor perception.
Section 4 analyses the proposed laser data and visual images fusion method, focused in the
reduction of the visual image area to the region of interest wherein objects are detected by
the laser. Two methods of segmentation are described in Section 5, to extract the shorter area
of the visual image (ROI) resulting from the fusion process. Section 6 displays the colour
based classification results of the largest segmented object in the region of interest. Some
conclusions are outlined in Section 7, and acknowledgements and references are displayed
in Section 8 and Section 9.projects: CICYT- DPI-2006-14497 by the Science
and Innovation Ministry, ROBOCITY2030 I y II: Service Robots-PRICIT-CAM-P-DPI-000176-
0505, and SEGVAUTO: Vehicle Safety-PRICIT-CAM-S2009-DPI-1509 by Madrid State
Government.Peer reviewe
Viewfinder: final activity report
The VIEW-FINDER project (2006-2009) is an 'Advanced Robotics' project that seeks to apply a semi-autonomous robotic system to inspect ground safety in the event of a fire. Its primary aim is to gather data (visual and chemical) in order to assist rescue personnel. A base station combines the gathered information with information retrieved from off-site sources.
The project addresses key issues related to map building and reconstruction, interfacing local command information with external sources, human-robot interfaces and semi-autonomous robot navigation.
The VIEW-FINDER system is a semi-autonomous; the individual robot-sensors operate autonomously within the limits of the task assigned to them, that is, they will autonomously navigate through and inspect an area. Human operators monitor their operations and send high level task requests as well as low level commands through the interface to any nodes in the entire system. The human interface has to ensure the human supervisor and human interveners are provided a reduced but good and relevant overview of the ground and the robots and human rescue workers therein
Adaptive sensor-fusion of depth and color information for cognitive robotics
Proceedings of: 2011 IEEE International Conference on Robotics and Biomimetics (ROBIO), December 7-11, 2011, Phuket (Thailand)The presented work goes one step further than
only combining data from different sensors. The corresponding
points of an image and a 3D point cloud are determined through
calibration. Color information is thereby assigned to every voxel
in the overlapping area of a stereo camera system and a laser
range finder. Then we analyze the image and search for the
locations, which are especially susceptible to errors by both
sensors. Depending on the ascertained situation, we try to
correct or minimize errors. By analyzing and interpreting the
images as well as removing errors we create an adaptive tool
which improves multi-sensor fusion. This allows us to correct
the fused data and to perfect the multi-modal sensor fusion
or to predict the locations where the sensor information is
vague or defective. The presented results demonstrate a clear
improvement over standard procedures and show that other
progress based on our work is possible.European Community's Seventh Framework Progra
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