1. The Rover Concept for the ESA ExoMars Mission
G. Gianfiglio, M. van Winnendael, J. Vago, P. Baglioni (European Space Agency)
F. Ravera (Alcatel Alenia Space Italia) L. Waugh - EADS Astrium Ltd (UK)
IEEE-ICRA 2007 workshop on Space Robotics
Rome, 14 April 2007
14th April 2007
Space Robotics Workshop ICRA07

2. The Rover Concept for the ESA ExoMars Mission
Automation and Robotics Section (TEC-MMA)
The Rover Concept for the ESA ExoMars Mission
Complementary Remarks
By L. Joudrier ESA-Robotics Section
14th April 2007
Space Robotics Workshop ICRA07

3. Space Robotics Workshop ICRA07
Forewords
Presentation of Rover – see proceedings for the mission details
All material presented is subject to change due to the on-going and coming industrial studies.
Additional pieces of information aiming to be potential seeds for discussions during this workshop.
Search for life on Mars a European key priority
First mission combines scientific and technological objectives
First autonomous European mission will pave the way for a significant European role in Mars exploration
14th April 2007
Space Robotics Workshop ICRA07

4. Space Robotics Workshop ICRA07
Presentation Outline
Forewords
ExoMars Mission
Objectives
Status
Overview
ExoMars Rover
Current baseline
Vehicle overview
Payload Support Equipment
Pasteur Payload
Surface Operations
RHUs & Planetary Protection
Considerations about the ExoMars Rover
Locomotion subsystem
Navigation
Autonomy
Planetary Protection
14th April 2007
Space Robotics Workshop ICRA07

5. Space Robotics Workshop ICRA07
Presentation Outline
Forewords
ExoMars Mission
Objectives
Status
Overview
ExoMars Rover
Current baseline
Vehicle overview
Payload Support Equipment
Pasteur Payload
Surface Operations
RHUs & Planetary Protection
Considerations about the ExoMars Rover
Locomotion subsystem
Navigation
Autonomy
Planetary Protection
14th April 2007
Space Robotics Workshop ICRA07

6. Space Robotics Workshop ICRA07
Mission Objectives
ExoMars is the first ESA led robotic mission of the Aurora Exploration Programme, combining demonstration of key enabling exploration technologies with major scientific investigations
Main technology demonstration objectives:
Safe Entry, Descent and Landing of a large size payload (Descent Module)
Surface mobility (Rover) and access to the subsurface (Drill)
Main scientific objectives:
Search for traces of past and present life and characterize Martian chemistry and water distribution
Improve the knowledge on Martian environment and identify surface hazards to future human missions
Search for life on Mars a European key priority
First mission combines scientific and technological objectives
First autonomous European mission will pave the way for a significant European role in Mars exploration
14th April 2007
Space Robotics Workshop ICRA07

7. Space Robotics Workshop ICRA07
Mission Status
Phase B1 on-going
Started in October 2005 with AAS-I as Prime Contractor
Extended to consider several options.
Selection of Major sub-contractors is completed.
ASTRIUM UK responsible for the rover
Selection of sub-contractors completed soon
SRR just completed
Implementation Review is next (May 2007)
Phase B1 to be completed by end of 2007
Integrated Locomotion-Navigation Rover Prototype
Launch date: 2011 unlikely so target is 2013 with back up 2015/2016 launch opportunity.
Search for life on Mars a European key priority
First mission combines scientific and technological objectives
First autonomous European mission will pave the way for a significant European role in Mars exploration
14th April 2007
Space Robotics Workshop ICRA07

8. Space Robotics Workshop ICRA07
Mission Overview
Launch a Descent Module to Mars with supporting spacecraft infrastructure for LEOP and Cruise Phase
Baseline: (Carrier + DM + Rover) Soyuz from Kourou + MRO
Option 1: additional Soyuz for a relay orbiter (MRO back-up)
Option 2: Ariane5 for ExoMars + carrier upgraded as orbiter (MRO back-up)
Release Descent Module into Mars atmosphere for automatic Entry, Descent and Landing (EDL) on Mars surface
Latitudes between –15º and +45º, all longitudes / Altitude ≤ 0 m relative to the MOLA zero level
Option: vented / non-vented airbag landing system
Egress of the Rover from the landed module
Accomplish Rover surface operations
180 sols minimum, 10 experiment cycles, ~1km distance between experiment locations
Search for life on Mars a European key priority
First mission combines scientific and technological objectives
First autonomous European mission will pave the way for a significant European role in Mars exploration
14th April 2007
Space Robotics Workshop ICRA07

9. Space Robotics Workshop ICRA07
Presentation Outline
Forewords
ExoMars Mission
Objectives
Status
Overview
ExoMars Rover
Current baseline
Vehicle overview
Payload Support Equipment
Pasteur Payload
Surface Operations
RHUs & Planetary Protection
Considerations about the ExoMars Rover
Locomotion subsystem
Navigation
Autonomy
Planetary Protection
14th April 2007
Space Robotics Workshop ICRA07

10. Rover Current Baseline
Mass ~ 180 kg (including Drill, SPDS and ~8kg Pasteur Payload)
Average Power ~ 120 W (by Solar Array assuming RHUs availability)
X-band communication link for DTE and UHF band for Proxi-link with MRO
Two Thermal Control solutions still under trade-off: with and without RHU’s
Concept with RHUs Concept without RHUs
14th April 2007
Space Robotics Workshop ICRA07

11. Space Robotics Workshop ICRA07
Rover Vehicle
Locomotion
6 wheels chassis
TTC
X-band for DTE
2 redundant transponders
2 redundant SSPA
1 RFDN
1 Small HGA (30cm dish, 24dBi gain)
UHF band for data relay with MRO
Internal redundant Proximity-1 compliant transponder
1 LGA (quad helix)
Power
Solar Arrays
Battery (Rechargeable, Li-Ion)
PCDU
Thermal Control System (TCS)
Two options under trade-off (with and without RHUs)
Loop Heat pipes, Radiators, Passive Thermal Switches
Navigation
Cameras (Nav. Cam, Haz. Cams)
Navigation sensors
Navigation Software (CNES)
Structure
Integrated units
Deployable mast for Cameras, IR Spectrometer and sensors
SA support and mechanisms
14th April 2007
Space Robotics Workshop ICRA07

12. Payload Support Equipment
Sample Acquisition System – To obtain surface and subsurface samples for analysis; includes a subsurface drill with rod exchange and positioning mechanism & a sample delivery mechanism, plus a surface rock corer (TBC)
SPDS – To prepare and present samples to all analytical lab instruments; includes distribution mechanisms and a milling station
Subsurface drill includes a miniaturised IR spectrometer for borehole investigations (Ma_Miss DIBS)
14th April 2007
Space Robotics Workshop ICRA07

13. Rover Scientific Payload: Pasteur
CONTEXT
- PanCam
- IR Spectrometer
- Ground Penetrating Radar
- Close-up Imager
- Mössbauer
- Raman-LIBS external
optical heads
- Microscope IR
- Raman - LIBS Spectrometers
- XRD
The instruments development is under the responsibility of relevant National Agencies
The current total mass of the Pasteur Payload Instruments exceeds the 8 kg allocation: if necessary instruments de-scoping will be implemented in line with the available resources (Payload Confirmation Review)
INSTRUMENTS SUPPORT EQUIPMENT
Drill System
(Surface and 2 m depth)
Includes Borehole IRS
Sample Preparation & Distribution System (SPDS)
ORGANICS/LIFE
- MOD/MOI
- GC-MS
- Life Marker Chip
ENVIRONMENT
- Dust & H2O Vapour Suite
- Ionising Radiation
- UV Spectrometer
- Meteo Package
To be accommodated into GEP
14th April 2007
Space Robotics Workshop ICRA07

14. Rover Surface Operations
The Surface Mission is composed of a sequence of Experiment Cycles (up to 10)
An Experiment Cycle consists of:
Identifying the location at which to perform the Measurement Cycle (from Ground Control)
Traveling to the new location (distance about 1 km between locations)
Performing a full Measurement Cycle using all instruments
Transmitting scientific, housekeeping and navigation data to the Relay Orbiter/Earth (Data volume ~ 1Gbit per Experiment Cycle)
During night the Rover goes into a sleep mode and resumes operations the following day
14th April 2007
Space Robotics Workshop ICRA07

15. Planetary Protection & Radio-isotope Heating Units
RHUs: Accommodation/location inside the internal enclosure is subject to trade-off between easy late access, proper heat distribution and interfaces with the Rover TCS
Planetary Protection: ExoMars is a class IVc mission allowing to search for past life and organic molecules in “special regions”. This is a major driver of the mission design, AIV, especially considering possible need of late access due to RHUs.
The sterilization concept is under study.
The PP mission class may be revised into IVb class (TBC).
14th April 2007
Space Robotics Workshop ICRA07

16. Space Robotics Workshop ICRA07
Presentation Outline
Forewords
ExoMars Mission
Objectives
Status
Overview
ExoMars Rover
Current baseline
Vehicle overview
Payload Support Equipment
Pasteur Payload
Surface Operations
RHUs & Planetary Protection
Considerations about the ExoMars Rover
Locomotion subsystem
Navigation
Autonomy
Planetary Protection
14th April 2007
Space Robotics Workshop ICRA07

17. Locomotion Subsystem 1/2
ExoMars current baseline is the RCL-type E with formula 6*6*4+4W
 Simple and light weight design passive articulated suspension
 No internal averaging mechanism
 Wheel-walking/peristaltic mode possible allowing highest mobility (Reuse of the motors necessary for deployment)
BUT
 Static stability issue depending of CoG (40 deg requirement)
 Eventually less performing compared to other concepts (Type D, Crab, R-bogie)
Possible improvements:
Formula 6*6*6+4W or 6*6*6+6W
RCL Type-D
RCL Type-E
14th April 2007
Space Robotics Workshop ICRA07

18. Locomotion Subsystem 2/2
ExoMars mobility requirements:
25 cm step obstacle
25 deg slope on specific soil
40deg stability any direction
Improvement of traction & obstacle crossing capabilities:
Use of terramechanics to define optimum wheel design (Single Wheel Testbed built within R&D activity “Rover Chassis Evaluation Tools”)
Possible use of flexible wheels [Richter ASTRA06]
Improved design of articulated suspension via simulation tools and prototyping.
Optimising the mass and power requirements remains a challenge at the expense of the scientific payload and desirable higher locomotion capabilities.
Locomotion risks due to unknown rough terrain are mitigated by high locomotion capabilities and (conservative) navigation.
14th April 2007
Space Robotics Workshop ICRA07

19. Space Robotics Workshop ICRA07
Navigation
Baseline is the use of the CNES Autonomous Navigation Software.
Accurate localisation is key. Visual Odometry & target tracking are required.
Solutions to definition target coordinates on ground by PIs to be experimented.
14th April 2007
Space Robotics Workshop ICRA07

20. Space Robotics Workshop ICRA07
Autonomy
ExoMars will require high degree of autonomy : Ground Control Staffing, amount of Telemetry to download, large distance traverses.
At least level E3 on the ECSS E70 autonomy scale (event driven reactive systems with some re-planning).
ESA Relevant R&D Activities (non exhaustive):
ESA Functional Reference Model (FRM) based on a 3-layered controller architecture (Mission-Task-Actions) equivalent to deliberative-executive-functional layers.
MUROCO: Formal specification and verification Tool [Kapellos-ASTRA06]. Use ESTEREL formal language to specify/Verify the rover behaviour (state machine composing the actions and tasks).
MMOPS: On-board planning/re-planning and scheduling tool [Woods-ASTRA06]
On-board model checking (just started) will allow advanced FDIR.
3DROV (on-going): full planetary rover simulator
14th April 2007
Space Robotics Workshop ICRA07

21. Space Robotics Workshop ICRA07
Planetary Protection
Based on the facts that:
During AIV process, 80 % of the bio-burden is brought by the AIV operators.
Sterilisation “kills the spores but does not remove the bodies” that may trigger organic molecule sensitive sensors designed to detect traces of past life.
ESA has initiated a feasibility study on Robotized AIV that would allow to reduce to the minimum the number of operators in the AIV clean rooms.
Robotized AIV is very challenging activity where space robotics and Earth state of the art robotics would be joined.
14th April 2007
Space Robotics Workshop ICRA07

22. Space Robotics Workshop ICRA07
Conclusion
ExoMars mission and rover current baselines have been briefly presented.
They will evolve along with the industry work.
Some relevant ESA R&D activities about rover have been presented to provide inputs to the discussion
Questions ?
14th April 2007
Space Robotics Workshop ICRA07