concept study for the faster micro scout...
TRANSCRIPT
Concept Study for the FASTER
Micro Scout Rover
R. Sonsalla
DFKI RIC
May, 16th 2013
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Outline
• Project Outline
• Idea and Objectives
• Mission Scenario
• Mission Architecture
• Design Considerations
• Scout Rover Prototype
• Outlook
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Project Outline
FASTER Forward Acquisition of Soil and Terrain data for
Exploration Rover
Funded by the 7th Framework Programme of
the European Commission (GA 284419)
Project Partner
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Main Work Packages
• Development of scout rover platform
• Development of light-weight soil sensors for the scout rover
Load testing feet
Ground penetrating radar
Hybrid dynamic plate and cone penetrometer
• Development of primary rover’s soil sensors
Wheeled Bevameter
PathBeater
• Development of cooperative autonomy for the rover team
• Development of autonomous traversal algorithms
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FASTER Idea and Objectives
FASTER Idea
Analyzing past and future exploration
missions and/or mission scenarios like MER
or MSR, a need arises to provide faster and
safer traversal of exploration rovers.
FASTER Objectives
Concept development, implementation and
demonstration of a system for in-situ
evaluation of soil properties
• to improve the mission safety and
• the effective traverse speeds using
• autonomous collaboration between the
primary rover and a small scout rover.
[1]
[1]
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Mission Scenario
• FASTER baseline scenario related to ESA/NASA
MSR-Mission and SFR-Architecture
Mission duration: 180 sols / 110 sols
traversing
Distance to traverse: 20 km
Time of traversal: 4 h/sol
Min. average rover speed: 1.25 cm/s
• FASTER traversal scenario
Based on waypoints
Path planning by primary rover
Use of SSS (scout & primary rover) to
assess trafficability
Low confidence in trafficability leads to path
replanning
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FASTER Architecture
• Primary Rover (BRIDGET)
With SSS-payload
• Scout Rover
With SSS-payload
As remote ‘sensor unit’
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Scout Rover System Context
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Scout Rover Concept Study
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System Decomposition
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Key Design Driver
• Scout rover mass: < 20 kg
(incl. payload)
• High all terrain mobility providing:
Traversability of slopes up to 25°
Static stability angles of 40 degrees
in all directions
Min. average speed of 1.25 cm/s
• Design challenges
Rover steering (wheel design)
Wheel sinkage on soft soil vs.
High mobility on rough terrain vs.
Digging over of soft soil
[1]
[2]
[2]
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Locomotion Concept
• Front: Hybrid legged-wheels
• Rear: Helical wheels
• Steering: Side-to-side
• Chassis: Body roll joint (1 DoF) Asguard v2
CESAR
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Initial Side-to-Side Steering Test
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Scout Rover Prototype
Prototype for first test
sequence, including:
Locomotion tests
Maneuver tests
Subsystem tests
Traversal tests
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System Overview
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Technical Overview
• Boundary Box: 400 x 830 x 500 mm
• Mass (incl. 20% margin): 14.8 kg / 18.4 kg
• Wheel torque: 28 Nm
• Average power: 100 W
• Peak power: 500 W
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Technical Overview
• Data Handling:
Distributed processing of operational data and payload data
• Communication:
Primary rover serves as relay station
Based on wireless access-point @ 2.4 GHz and 54 Mbps
• Navigation:
Optical navigation System based on stereo camera and laser range finder
Body pose measurement based on motor position and torque measurement, IMU and body joint angular encoder
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Outlook
• Locomotion performance tests
• Navigation tests
• Implementation of autonomous
rover-to-rover collaboration
• Soil sensor integration
• Dual rover team soil examination
and traversal tests
FASTER Demonstration Workshop
November 2013
in Warsaw, Poland
https://www.faster-fp7-space.eu/
Thank you!
https://www.faster-fp7-space.eu/
Contact
Thomas Vögele (Project Manager),
Roland Sonsalla (Systems Engineer) German Research Center for Artificial Intelligence
email: [email protected]
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References
[1] L. Richter et.al., “Freeing the Spirit Rover on Mars –
Progress Report” on 11th European Regional Conference of
the International Society of Terrain-Vehicle Systems
(ISTVS), October 2009, Bremen, 2009
[2] M. Golombeck et.al., „Rocks at the MSL Landing
Sites“, 4th MSL Landing Site Workshop, September 2010,
Monrovia, CA, 2010
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Baseline Operational Scenarios
• Normal Operation
Use of elevation map in combination with waypoints and scout position
Travel along predefined path (about 4 m ahead of primary rover)
Perform soil and terrain sensing and hazard avoidance
• Scouting Operation
Use scout rover as remote stereo camera for scouting
Expand elevation map on primary based on stereo images of scout
• Survival Operation
Follow previous path back using the last received elevation map
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Structure & Mechanism
• Mass (incl. 20% margin) 14.8 kg (excl. Payload)
18.4 kg (incl. Payload)
• Boundary Box (h x l x w) 400 x 830 x 500 mm
• Chasis: 1DoF in roll direction
• Locomotion and Steering Front: hybrid legged-wheels
Rear: helical wheels
Side-to-side steering
• Actuators: 4 x Robodrive with HarmonicDrive (28 Nm max.)
• Climbing Front: min. 224 mm
Rear: min. 100 mm
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OBDH and COM
• On Board Data Handling
Distributed processing of scout rover
operational data (OBC) and payload data
(PDH)
OBC: Embedded single board computer
PDH: Sensor related micro controller
• Communication
Primary rover serves as relay station for
scout rover communication
COM module:
Wireless access-point (802.11g wifi-module)
UHF emergency control
Asus WL-330gE
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EPS and TSC
• Electrical power supply
Assumed average power: 100 W
Estimated peak power: 588 W
Power supply:
LiPo accu: 44.4 V @ 2.1 Ah
External power supply
• Thermal Control System
Passive control for motor
modules
Active control for OBDH
Temperature sensors for
HMS
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Navigation
• Two different sensor packages are
planned for the scout rover navigation
system
1.Optical Navigation System
Stereo camera (2 x Guppy by AVT)
Scanninc laser range finder
2.Body Pose Measurement
AHRS (IMU) attached to main body
Body joint angular encoder
Motor position and torque
measurement
Guppy by AVT
AHRS by Xsens
UTM-30XL by Hokuyo
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Payload Integration Study
• Scout Rover SSS-payload:
Load Testing Feet and Belly Camera
Ground Penetrating Radar
Dynamic Plate and Cone Penetrometer