Mobile Payload Element (MPE)

Size: px

Start display at page:

Download "Mobile Payload Element (MPE)"

Jared Joseph
5 years ago
Views:

1 Kayser-Threde GmbH Space Industrial Applications Mobile Payload Element (MPE) Concept Study of a small autonomous, and innovative Sample Fetching Rover R. Haarmann 1, Q. Mühlbauer 1, L. Richter 1, S. Klinkner 2, C. Lee 2, C. Wagner 2, R. Jaumann 3, A. Koncz 3, H. Michaelis 3, J. Schwendner 4, H. Hirschmüller 5, A. Wedler 5 (1) Kayser-Threde GmbH, Wolfratshauser Strasse 48, Munich, Germany, richard.haarmann@kayser-threde.com, Telefon: , Fax: (2) von Hoerner & Sulger GmbH, (3) DLR Institute of Planetary Research, (4) German Research Center for Artificial Intelligence DFKI, (5) DLR Institute of Robotics and Mechatronics

Introduction Mobile Payload Element (MPE) Small, autonomous, innovative vehicle of roughly ~15 kg Operating in the challenging environment of the lunar south pole acquires samples of lunar soil ~100m

Exploration Program under Cooperation of ESA & ROSKOSMOS (under discussion) Phase 0/A: April 2011 March 2012 concluded with successful PRR Ongoing Activites Delta Phase A: October 2012 October 2013

2 Introduction Mobile Payload Element (MPE) Small, autonomous, innovative vehicle of roughly ~15 kg Operating in the challenging environment of the lunar south pole acquires samples of lunar soil ~100m around its lander brings them back to the spacecraft for further analysis German national contribution to the ESA Lunar Lander Mission cancelled in fall 2012 Alternative: contribution to a Moon Exploration Program under Cooperation of ESA & ROSKOSMOS (under discussion) Phase 0/A: April 2011 March 2012 concluded with successful PRR Ongoing Activites Delta Phase A: October 2012 October 2013 Locomotion Subsystem Avionics Close-up Imager Sample Transfer Mechanism Image courtesy to ESA Autonomy Payload Experiment & Illumination Prediction Image courtesy to Roskosmos 2 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Reference Scenario & Model Payload Reference Scenario

conditions Operation Communication Power, MPE Model Payload

locally shaded terrain surface, subsurface underneath large

characterization of the sample material A Camera Payload:

Mole sampler Close-Up Imager Philae ROLIS Close-Up Imager 3

3 Reference Scenario & Model Payload Reference Scenario Realistic background for subsystem trade-offs Environmental conditions Operation Communication Power, MPE Model Payload and Sampling Acquisition of regolith samples illuminated and locally shaded terrain surface, subsurface underneath large boulders Documentation of the samples In-situ characterization of the sample material A Camera Payload: Stereo camera with LED-illumination A Scientific Payload: Mole sampler Close-Up Imager Philae ROLIS Close-Up Imager 3 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013 Stereo Camera MOLE Sampling Device

4 MPE Overview Active Chassis adaption of each wheel to the surface alignment of solar generators and instruments

regions: >2h Survivable darkness periods: >13h Communication UHF-band (up/down): 9.

2 axes inclinometer Wheel and body encoders Operational Modes Tele-operated mode Autonomous mode Mass Budget Summary

4 4 MPE Overview Active Chassis adaption of each wheel to the surface alignment of solar generators and instruments Power Supply System Solar generators: 25W Secondary battery: 160Wh Active Thermal Control System Operation in shaded regions: >2h Survivable darkness periods: >13h Communication UHF-band (up/down): 9.6 kbit/s S-band (down): 512 kbit/s Onboard Computer LEON3FT GR712RC Sensor Package Stereo Camera LED flash lighting 2 axes inclinometer Wheel and body encoders Operational Modes Tele-operated mode Autonomous mode Mass Budget Summary MPE Concept Phase A Total Mass incl. Margin [kg] MPE (Rover + Payloads) 15,777 Rover (w/o Payload) 13,525 Camera Payload 0,305 Scientific Payload 1,948

5 MPE Overview Mole Sampler 303mm Close-up Imager 740mm 823mm 900mm 990mm 493mm 660mm 700mm 493mm 541mm 5

Compatibility to the Russian Moon Exploration Programm Current Situation ESA Lunar Lander Mission Stopped in fall 2012 Lunar Resource/Chandrayaan-2 Terminated in January 2013 ESA and Roscosmos

on lunar south pole area in highly illuminated areas Collection of soil samples Rover weight: ~10kg - ~15 kg Mission duration: 6-9 months - 12 months Conclusion: MPE it is highly suitable for an

6 Compatibility to the Russian Moon Exploration Programm Current Situation ESA Lunar Lander Mission Stopped in fall 2012 Lunar Resource/Chandrayaan-2 Terminated in January 2013 ESA and Roscosmos currently discuss a corporate lunar exploration program A future program will probably comprise a rover mission, similar to Lunar Lander or Lunar Resource Both missions were very similar: Operation on lunar south pole area in highly illuminated areas Collection of soil samples Rover weight: ~10kg - ~15 kg Mission duration: 6-9 months - 12 months Conclusion: MPE it is highly suitable for an upcoming ESA/Russian Mission If usage of RTG s and RHU s are possible (like Lunar Resource) Survival capabilities of darkness periods could be increased 6 5/15/2013 Mobile Payload Element (MPE) - ASTRA 2013 Image courtesy to Roskosmos Image courtesy to Roskosmos

Actuator Design ILM 38 Motor Units Actuator design is based on permanent magnet synchronous motors,

unit Same technology was further developed for DexHand and MASCOT Advantages of those ILM actuators

components Trade-Offs led to Incorporation of PTFE sealing combined with labyrinth Potentiometer as

7 Actuator Design ILM 38 Motor Units Actuator design is based on permanent magnet synchronous motors, developed at DLR RMC Combined with low backlash Harmonic Drive gears Derived from ROCKVISS actuation unit Same technology was further developed for DexHand and MASCOT Advantages of those ILM actuators Well suited for high dynamic tasks High efficiency High torque capacity Low number of mechanical components Trade-Offs led to Incorporation of PTFE sealing combined with labyrinth Potentiometer as absolute position sensor (position controlled actuators only) 7 5/15/2013 Mobile Payload Element (MPE) - ASTRA 2013

Wheel Design Requirements Provide ground interaction Withstand static & dynamic loads Withstand temperature cycles Parameters MPE nominal velocity: 5.

) Terrain: lunar Regolith with varying degree of compactness Minimum diameter: 250mm accommodation of driving and steering actuator within the wheel Approach

8 Wheel Design Requirements Provide ground interaction Withstand static & dynamic loads Withstand temperature cycles Parameters MPE nominal velocity: 5.4 mm/s (tele-ops.) Terrain: lunar Regolith with varying degree of compactness Minimum diameter: 250mm accommodation of driving and steering actuator within the wheel Approach Several concepts were established and evaluated 3 wheel-options were designed and traded Wheel properties and strength were determined Wheel Design Diameter: 250mm Width: 60mm can be reduced down to 40mm 25 Grousers 8 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013 Mass: Al-Version: 267g Ti-Version: 160g

9 Integrated Avionic Design Design Drivers Minimal volume and mass. Efficient use of solar & battery power minimal energy wastage on unused functions. Prevention of fault propagation in-built fault tolerance whenever possible Extreme non-operational cold environment System Layout Power subsystem Rover subsystem Communications Onboard computer Actuator subsytem Payload Subsystem Payload power control Interfaces Backplane Ground bar Starpoint 9 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

of 128 MB Power and communication driver electronic Can be completely switched on/off Enhances the MPEs autonomy functions Advanced dense stereo matching methods can be

10 Autonomy Payload Experiment Optional payload on MPE Additional pan/tilt unit (see A. Wedler, ASTRA 2013, Paper# ) Additional FPGA (Virtex 4QV (XQR4VFX60) or Virtex 5) Flash module with the bitstream to program the FPGA RAM module with storage size of 128 MB Power and communication driver electronic Can be completely switched on/off Enhances the MPEs autonomy functions Advanced dense stereo matching methods can be implemented (e.g. SGM) Allows stereo rectification Further image compression allows 1.5 Hz image stream down to Earth Allows full autonomous driving Increases accuracy & robustness Increases the MPE speed 10 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

terrain Concept Combination of DEM and horizon models DEM centered at the lander location Generated by LRO Data before landing Generated by lander after landing Updated

11 Illumination Prediction Challenging Illumination Conditions Max. Sun inclination: 3 over the horizon Complex and dynamic illumination situation at ground level Illumination condition is highly dependent on the local shape of the terrain Concept Combination of DEM and horizon models DEM centered at the lander location Generated by LRO Data before landing Generated by lander after landing Updated by stereo images of MPE DEM has size of MPE operational area Horizon rings provide max. terrain elevation for angular subsection Angular resolution independent from distance Multiple rings to compensate for parallax errors 11 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Sample Transfer Endeffector on lander s robotic arm Completely passive device, actuated via arm force Opening by pressing it on ground Closing via springs Protects sample from direct solar

12 Sample Transfer Endeffector on lander s robotic arm Completely passive device, actuated via arm force Opening by pressing it on ground Closing via springs Protects sample from direct solar illumination Ability to take surface samples Ability to receive samples from mole Ability to transfer mole/surface samples to instrument ports Protection against clogged material / cross contamination (via Piezo) Further concepts will be assessed and detailed Mole 12 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Close-up Imager Contradictory requirements lead to a

multispectral Close-up Imager (CUI) Sample characterization

length: ~45mm High resolution: 33μm/pixel (1920x1080 CMOS)

Wide-Angel rear view FoV: 89 Low resolution: ~512x 512 pixel

margin) Power: 5W (multispectral imaging) Mirror Close-Up

13 Close-up Imager Contradictory requirements lead to a two-lens/two detector design approach Narrow-angle multispectral Close-up Imager (CUI) Sample characterization Focusing towards the mole LED Illumination FoV: 17,85 Focal length: ~45mm High resolution: 33μm/pixel (1920x1080 CMOS) Wide-angle Rear Camera Tele-operated backward driving Wide-Angel rear view FoV: 89 Low resolution: ~512x 512 pixel (to keep data rate low) Total CUI mass: 0.73kg (incl. margin) Power: 5W (multispectral imaging) Mirror Close-Up Imager Narrow Angle Optics Detector Rear Camera 13 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Summary & Outlook MPE is the first sample fetching rover worldwide in the 15kg-class: dedicated mobile sampling device Provides access to uncontaminated scientific interesting objects in an

boulders and blocks MPE is versatile and can be incorporated in several missions Innovative rover for technology demonstration as well as for the A&R community MPE has a high public outreach

14 Summary & Outlook MPE is the first sample fetching rover worldwide in the 15kg-class: dedicated mobile sampling device Provides access to uncontaminated scientific interesting objects in an area ~100m around the Lunar Lander Controlled sample volume Regolith samples from surface and subsurface Regolith samples from illuminated and locally shadowed terrain as well as from below boulders and blocks MPE is versatile and can be incorporated in several missions Innovative rover for technology demonstration as well as for the A&R community MPE has a high public outreach potential Image courtesy to NASA The Mars The Pathfinder Mobile Payload microrover Element Sojourner observed observed by its lander by its lander 14 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

MPE Summary & Outlook The MPE study had a successful PRR Review and Final Presentation at DLR Space Management in March 2012 The current MPE Delta Phase A started in October 2012 with focus on

15 MPE Summary & Outlook The MPE study had a successful PRR Review and Final Presentation at DLR Space Management in March 2012 The current MPE Delta Phase A started in October 2012 with focus on critical technologies and breadboard preparation The MPE Team envisages to continue with a breadboard and testing phase, beginning in late 2013 The Mobile Payload Element is an excellent opportunity for the demonstration of European competences in space robotics 15 15/05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Thank You Richard Haarmann Richard.Haarmann@Kayser-Threde.

16 Thank You Richard Haarmann Aknowledgements: The MPE study was funded under DLR contracts 50JR1006 and 50JR /05/2013 Mobile Payload Element (MPE) - ASTRA 2013

Pan/Tilt-Unit as a Perception Module for Extra- Terrestrial Vehicle and Landing Systems

www.dlr.de\rm Chart 1 > ASTRA 2013 - Pan/Tilt-Unit as a Perception Module 16.05.2013 Pan/Tilt-Unit as a Perception Module for Extra- Terrestrial Vehicle and Landing Systems DLR-RMC Robotic and Mechatronic