Lunar Regolith Protection System Dalhousie University Mechanical Engineering MECH 4020 Team #3

Problem Definition 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 Team #3 Apr Slide #2 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Fall Semester Design Team #3 Apr Slide #3 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Final conceptual design as of December 08

Final Design Team #3 Apr Slide #4 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Improvements made to December 08 design

Adjustable Brackets Team #3 Apr Slide #5 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Allow for fine-tuning of SMA orientation before the range of motion becomes consistent Final dimensions of SMAs would be used Fasteners eliminated from actual model

Lid Team #3 Apr Slide #6 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Lid profiles unchanged Additional lip on minor lid to prevent dust from infiltrating seam

Base Team #3 Apr Slide #7 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Male mating surface along rim for accurate seating of lids SMA attachment moved to base plate

Active Protection System Team #3 Apr Slide #8 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Charged particles are attracted to the capacitor plates and will not interfere with LIDAR operation Testing demonstrated that 100% of charged particles are collected

Testing: Active Protection System Team #3 Apr Slide #9 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Capacitor mock-up in Styrofoam block Arcing caused by plates being too close

Nitinol (NiTi) actuator alloy Transformation Temperature: 40 o C SMA Hinge Team #3 Apr Slide #10 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

SMA Hinge Team #3 Apr Slide #11 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Thin-film Heaters Final Dies

Testing: SMA Hinge Team #3 Apr Slide #12 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions SMA Wire Small SMA Strips

Testing: SMA Bowing Team #3 Apr Slide #13 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Passive Strip Active Strips Clamping Bars

Complete System Team #3 Apr Slide #14 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Complete System Team #3 Apr Slide #15 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

System Performance Team #3 Apr Slide #16 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions Parameter Active System Power Requirement 0.5 W-SS 1.0 W-Peak SMA Hinge Power Requirement20 W Consistent Range of Motion75 degrees Opening TimeApprox. 20 s Closing TimeApprox. 20 s Minimum Cycle Time10 min SMA Transition TemperatureApprox. 40 deg C Max. Operational SMA Temperature (8.5W/in2)80 deg C Particle InfiltrationTrace

System Performance Team #3 Apr Slide #17 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Power requirements Lid mating and range of motion Limitations Team #3 Apr Slide #18 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Budget Team #3 Apr Slide #19 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements ConclusionsExpenseCost SMA Strips $280 Thin-film Heaters $640 Power Supply $80 Teflon $120 Rapid Prototyping $290 Miscellaneous (hardware, wiring, etc.) $30 TOTAL EXPENSES $1440 BUDGET $1450

Requirements Team #3 Apr Slide #20 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements ConclusionsConstraintsMet? Withstand extreme thermal conditions Withstand high radiation environment Must not rely on gravity No unvented cavities Must not interfere with LIDAR operation

Requirements Team #3 Apr Slide #21 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements ConclusionsCriteriaMet? Minimize power requirements Minimize weight and size Last at least 3 months in lunar environment Minimal regolith accumulation on instrument

Conclusions Complexity of lunar environment Multi-layered solutions are critical for dust protection Design strengths –SMA hinge –Lid geometry –Active protection Team #3 Apr Slide #22 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Acknowledgements Dr. Andrew Warkentin Dr. Marie-Josée Potvin Dr. Julio Militzer Dalhousie University Mechanical Engineering Department Shell Canada Team #3 Apr Slide #23 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions

Questions? Team #3 Apr Slide #24 Problem Definition Fall 08 Design Final Design Adjustable Brackets Lid and Base Active Protection System SMA Hinge Complete Design Performance Limitations Budget Requirements Conclusions