Transcript Diapositiva 1 - CONFERENCE CENTER

Zereik E., Biggio A., Merlo A. and Casalino G.
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Agenda
• Introduction
• TBRA Overview
• Objectives
• Architecture / Technical Description
• Perception Capability
• DEM and Data Fusion
• Test Results
• Conclusion
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Introduction
• Rover GNC:
Navigation
• Localisation
• Trajectory Control
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• Reach goal
• Safe and best path
•
Environment perception
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
TBRA Overview
• TBRA innovative aspects
 Flexibility
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modular software architecture
each module provides a key functionality of the GNC
 Modularity
 Resulting from the standardization of the interfaces and data
structures exchanged between the software modules
• No “ad-hoc development” typical of space applications
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Project Objectives
• Acquisition of experience in robotics for space exploration
 Team Growth
• Validation and Testing of GNC algorithms
 Complete mobile robotic platform development
• New solutions for the space market
 No “start from scratch”
 Support to programs, project and study development
• Anticipate future exploration mission needs
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Innovative Sensors (Omni-camera, Time-of-flight Camera, …)
Robot Swarms
Manipulation
Samples Fetching and Handling
Opportunistic Science
Reactive Navigation
Simultaneous Localization and mapping (SLAM)
…
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Functional Overview
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Architecture
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Robotic Setup
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Single Functionality Testing
Navigation – Perception
Navigation – Traversability
Navigation – Path Planning
Localisation – Visual Odometry
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Perception Capability
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Single Perception
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Single Reconstruction
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
PTU Model
• frames <base>, <pan>, <tilt> and <ptu>
located in the same point A
base
pan
• panT , tiltT function of pan/tilt angles
• contribution also to translation as the
camera does not rotate with respect to its
reference frame origin
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Multiple Perception
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Multiple Reconstruction
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Camera Digital Elevation Model
• blue means navigable, red means
obstacle, black means unknown
• 400 x 400 (pxl) planar image
• rover located at the image centre
• each pixel represents a world area
of 5 cm x 5 cm
• black pixels just behind the box
due to the occlusion of the box
itself
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
3DLS Digital Elevation Model
• sparse after 2-3 m
• 0.25 deg 3DLS angular
resolution
• 10 deg/s speed
• resolution limited to reduce
perception time
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Data Fusion
• Data fusion policies:
• Visual DEM or Laser DEM only
no fusion at all
• Both DEMs but Vision has the higher priority
• Both DEMs but Laser has the higher priority
• Merging of both DEMs
• Filtering strategy for
• Noise
• Mismatched correspondences
• Bad illumination
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Single Sensor DEM
• Apply the filtering to each point from the sensor
• Assign each computed value to the final DEM
Filtering
(Median,…)
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Multiple Sensor DEM
• Apply the filtering to each point from the higher priority sensor
• If the pixel is invalid, filter the corresponding value from the other sensor
• Assign the computed value to the final DEM
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Weighted Merging
• Each pixel of each sensor DEM assigned to a confidence according to
some criteria:
• less considered points
• far away from the camera
• located at the very side of the camera field of view
• Perform a weighted fusion
• Data filtering
• improve DEM accuracy
• avoid errors such as false obstacle detection
BUT
• be careful not to delete obstacles!!!
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Conclusions
• Rover:
• Autonomous navigation both indoor and outdoor
• Many GNC sensors integrated
• New GNC sensors and (functionalities) to be added
• Omni-camera
• Time-of-Flight Camera
• Manipulator
• Focus on algorithms only
• Portability on different platform
• No “ad hoc” development
• No “from scratch” development
• Testing and Validation Tool
EUCASS 2011 – 4-8 July, St. Petersburg, Russia
Questions?
EUCASS 2011 – 4-8 July, St. Petersburg, Russia