Hy-V .1

1. Hy-V Hy-V .1 Skin Friction Sensor Experiment Presenters: Ryan F. Johnson Mitchell Foral-Systems University of Virginia November 24, 2008

2. Outline • Overview • Science of Sensor • Special Mission Requirements • Mechanical Drawings • Commands and Sensors • Test Plans • Compliance and Shared Logistics • Management Update • Schedule • Missing: • Subsystem Requirements • Parts list

3. Overview • Objective: • To test a newly designed skin friction sensor fabricated by ATK • Students to gain experience in several areas of engineering by engaging in a student run sounding rocket experiment • Expected findings: • Functionality of the skin friction sensor • Analytically determined skin friction matches that of the sensor • Reusability of sensor • Survivability of sensor

4. Science of Sensor • Skin friction is a necessary element for the understanding of fluid dynamics • Skin friction • The reason we fly • The reason why we can’t fly that fast • The more we understand skin friction the better chance we have to design flight vehicles that can sustain high speed flight Image from NASA HYPER-X found: http://rocketpedia.rocketmavericks.com/aerodynamics/images/5/55/X-43A_(Hyper_-_X)_Mach_7_computational_fluid_dynamic_(CFD).jpg

5. Science of Sensor • Sensor uses an interferometer to measure deflections that will translate into voltage outputs • Interferometer • Uses two light waves that intersect at a certain point • Skin friction causes a defection of one of the reflective mirrors • Depending on their deflections, constructive and destructive interference can be measured • This measured interference will then be translated into an output voltage t

6. Rocket Skin Top View Flow Rocket Interior Special Mission Requirements • For experiment, UVA needs atmospheric access other than the supplied static ports • These ports will need to accommodate the skin friction sensors • Adapters will be designed by UVA and cleared by NASA • Will communicate with NASA over the next few weeks leading to CDR to determine the best route to accommodate sensor • PRIORITY: Sensor integration will need to be water tight • Water leak will damage other instruments and void compliance agreement • Any assistance from boulder in this would be greatly appreciated

7. Sensor bases: One for Each Sensor PCM104+ Lifted Base Plate Mechanical Drawings: RockSAT Can Base

8. Mechanical Drawings RockSAT Can with Integration of sensors Two sensors attached to wall

9. Mechanical Drawings RockSAT can integrated into rocket Skin • Two sensors • Two holes • 2-¾” taps • Need to be sealed

10. Mechanical Drawings Possibilities for sensor integration • Tap holes • Can seal holes with rubber sealing to prevent leaks • Would need to drill more holes to bolt sensors to wall 1 • 2. Use a skin mount • Mounts into a window located on the outer wall of the rocket • Less holes in skin • Integration into rocket easier 2

11. Future Analysis • Center of mass • Use Cosmos to create G-Loads on payload • Tests material selection and design • Look into water tight sealing • Using rubber gasket (seen to the right) • Using spray foam • Calculate true center of mass • Currently center of mass can be counterweighted because payload weight is 3lbs max • True center of mass will be known after material selection and counterweights are chosen • Determination of Skin friction from CFD • Determination of wall temperature from CFD

12. Flow Chart Diagram for Flight Test Assessment of Test Board Turns on Sensors Power on Recovery of DATA Ignition of Rocket Tripping of G-Switch Code Execution Begins Recovery of Rocket De-integrate Sensors Is memory Full? Splash Down Yes Stop Code No Keep Executing Code

13. Commands and Sensors • Data Flow: • Shear sensor -> Circuit board -> CPU -> Software -> Storage • Sensor: • Operates in excess of 1000 degrees C. • Between 4 and 10 mm^2 in surface area. • Frequency response in the kHz range. • Sampling: variable; factory default of 50Hz. • Storage: 16MB. • Sample time: ~2.7 minutes at 50Hz for 16-bit data. • Software: • Poll for incoming data -> optimize for storage -> store • Maybe sample at very high Hz, store mean at low Hz.

14. Test Plans • Preflight Testing: • Sensor outputs between 0 and 5 V data. • Our microprocessor/board has a software suite to test programs written for it. Feed it fake sensor data. • Once those tests pass, we can attach the sensor to the board and run actual tests. • Flight: • Potential failure points: • Hardware failure. • Flight lasts longer than expected, run out of storage for samples.

15. Compliance and Shared Can Logistics • Compliance: • Mass, Volume • Currently 3lb payload (not including can) • Payload activation • Remove before flight pin • G switch • No volt requirement???? • Can Logistics: • Shared with VT • VT supplies PC104+ • VT has one other experiment (TBD) • Both collaborate on rocket integration and design

16. UVA Hy-V 0.1 Team • Management • Ryan Johnson-Program Manager • Elizabeth Martin- Technical Advisor • Mechanical Engineering • Archie Raval • Shaun Masavage • Jesse Quinlan • Aerospace Engineering • Naeem Ahmed • Systems: • Mitchell Foral • Chris Sweeney

17. Schedule • Next few weeks • Coordinate with NASA and Boulder on special requirements • Order special components • Material Selection • Center of Mass Calculation • Complete Systems Charts (Coding, Block Diagrams) • Secure Funding • VSGC • ATK • Next Few Months • Calculate expected shear • Receive sensors • Finish coding for PC104 • Complete and finalize models • Run G Load analysis • Determine max, min shear for sensor • Determine Total temperature for sensor • Run preliminary tests

18. Conclusion • We have A LOT to do!!!! • We are not lazy, just have had bad luck • Need to catch up, probably more than any other RockON Team • Complete confidence that Hy-V Team can do this • With the help of Advisors from UVA, VT, UC at Boulder, and NASA Wallops we can make this happen