Lunar Regolith Protection System

1. Lunar Regolith Protection System Dalhousie University Mechanical Engineering MECH 4010 Team #3

2. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #3 Problem Definition Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Design an apparatus or system to protect Light Detection and Ranging System (LIDAR) instrument from regolith • Improve upon Phoenix design • Design must function in a lunar environment

3. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #2 Background Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • LIDAR • Comprised of laser and receiver • Measures atmospheric and geomatic properties • Lunar Environment • 28-day lunar rotational period • 1/6 gravity of earth • No atmosphere • Extreme temperatures (max range: -220 – 120 oC) • Micro-meteorites • High radiation

4. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #2 Background Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Regolith • Highly abrasive • Irregular shape • Abundant in lunar environment • Small particle size • Electrodynamic properties Source: JPL/NASA

5. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #4 Requirements Background Problem Definition Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Constraints • Withstand extreme thermal conditions • Withstand high radiation environment • Must not rely on gravity • No unvented cavities • Must not interfere with LIDAR operation • Criteria • Minimize power requirements • Minimize weight and size • Last at least 3 months in lunar environment • Minimal regolith accumulation on instrument

6. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #5 Control circuitry for thin film heaters SMA Actuated Flexible Lid Rolls back Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Roll-back lid actuated by SMA strips embedded in flexible material • Complicated control circuitry required

7. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #6 Modification of Original Lid Motor and hinge Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Modify geometry to control the position and flow of dust particles • Bulky design • Risks associated with motor hinge

8. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #7 Magnetic Vacuum Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Solenoid / Permanent magnet • Excessive loads on moving components • Magnetic properties of regolith are not validated

9. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #11 Final Design Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements

10. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #8 Passive Protection Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Lid profile • Overlapping mating surface

11. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #9 SMA Hinge Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Each hinge comprised of 3 Nitinol (55% - Ti 45% - Ni) strips (2 for closing, 1 for opening) • Activated by thin-film heaters

12. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #10 Active Protection Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Capacitor • “Collar” located in base around receiver • “Electric curtain” • Vacuum acts as near perfect insulator

13. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #12 Preliminary Testing Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Rapid prototyped lid and base design • SMA wire hinge • COMSOL models of capacitor design

14. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #13 Current Status Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Awaiting SMA strips • Improving machinability of lid design • Developing testing plan • Lid profiles • Mating surfaces • SMA hinges • Capacitor

15. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #14 Conclusions Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Complexity of lunar environment • Multi-layered solutions are critical for dust protection • Design strengths • SMA hinge • Lid geometry • Active protection • Operational protocol

16. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #15 Acknowledgements Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements • Dr. Marie-Josée Potvin • Dr. Andrew Warkentin • Dalhousie University Mechanical Engineering Department • Shell Canada

17. Lunar Regolith Protection System Team #3 Dec 1 2008 Slide #16 Questions? Problem Definition Background Requirements Alternative Designs Final Design Preliminary Testing Current Status Conclusions Acknowledgements