1. Joe Mozloom Eric Marz Linda McLaughlin Swati Maini Swapnil Mengawade Advisor: Jin Kang, PhD

2. Objective Drexel's RockSat payload will incorporate a platform rotating opposite the spin-stabilization of the Terrior-Orion sounding rocket during ascent, resulting in a rotationally static platform from an outside reference frame.

3. Purpose Experimentally determine the feasibility of a despun platform under high acceleration and turbulence, driven by a low power system. Provide a stable platform with respect to the exterior environment to accommodate experiments requiring constant frame of reference in a traversing object.

4. Theory A Microelectromechanical systems (MEMS) gyroscope is based on the physical principal that a vibrating object will continue to vibrate along the same plane as its support is rotated. MEMS Gyroscopes utilize Coriolis Effect The apparent defection of a moving object when viewed from a rotation reference frame.

5. Mission RequirementsMethodStatus Design and implement a despun platform Design, TestingIn Progress Successfully store and recover system data Design, TestingIn Progress Meet all NASA / WFF canister requirements DesignIn Progress

6. Despun Platform System Requirements MethodStatus Controller must be operational when rocket is spinning from 0.5Hz-10Hz Design, TestingIn Progress Despun platform max angular velocity 10% of fixed platform max angular velocity Design, TestingIn Progress System must be functional at 25 g acceleration longitudionally,10 g acceleration laterally Design, TestingIn Progress Motor must be able to accommodate the required RPM at high acceleration and accompanying friction Sourcing, Design, TestingIn Progress

7. Data Handling System Requirements MethodStatus Size of flash memory large enough to store all data generated during ascent Design, TestingIn Progress Data retrievable even after submerged in water Design, TestingIn Progress All systems effectively "talking" to micro-controller and subsequently memory Design, TestingIn Progress

8. NASA / WFF System Requirements MethodStatus Max Height = 8 cm (1/3 Volume) DesignIn Progress Max Mass = 2 Kg (1/3 Mass)DesignIn Progress Securely attached to Sub-SEM ring assembly Design, TestingIn Progress Center of Mass envelope of 1 in cube at center of canister DesignIn Progress G-switch activation at launchDesignIn Progress

9. Workbench Meet all NASA / WFF requirements Counter-rotating platform effective from 0.5 Hz - 10 Hz Maximum platform spin-rate 10% of maximum canister spin-rate Data is reliably collected and is usable Flight Meet all NASA / WFF requirements Counter-rotating platform engaged when canister is spinning Platform able to rotate under harsh flight conditions Data is reliably collected and is usable

10. Despun platform rotates against the rotation of rocket System capable of surviving and functioning in launch environment

11. Leonard Blaisdell, Richard Rubin, Otto Mahr. "ATS Mechanically Despun Communications Satellite Antenna." IEEE Transactions on Antennas and Propagation 17 (1969): 416-28. Successful mechanically despun internal payload (for antenna use) Currently, minimal research has been completed regarding despun payloads during ascent. Most despun applications occur in orbit and utilize external thrust vectoring of entire rocket.

12. Payload consists of a platform fixed to canister Will spin at the same rate as the spin stabilized Terrior-Orion Rocket Platform to be despun elevated above fixed platform Able to freely rotate about the longitudinal axis of rocket Attached to the fixed platform via slip ring Allows data transfer with unrestricted rotational movement. Outside edge of despun platform geared to interface with motor Geared platform will be rotated via electric motor(s) attached to the fixed platform Motors spin geared platform equal and opposite the angular velocity of rocket Gyroscope (possibly accelerometer) will be utilized on the fixed platform to calculate spin rate, and will be fed into the motor via a microcontroller Despun platform will also have a gyroscope (or accelerometer) to calculate the platform spin rate for data collection and comparison

13. Gyroscope Motor(s) Gyroscope Despun Platform Data Handling, Storage, and Power Platform attached to Canister Despun platform post with bearings and slip-ring

14. MicrocontrollerMotor Despun Platform Gyro Fixed Platform Gyro Memory

15. Low Voltage Electric Motor(s) Slip-ring for data transfer Low-Friction Bearings Microcontroller Memory 9V Battery(s) MEMS Gyroscopes

16. Sharing 1/2 can with Temple University Temple University will be measuring gamma and x-rays, up to 100keV, through the use of a scintillator and photomultiplier-tube. They will use visible solar light as a directional z-axis reference point to characterize the high energy particles as solar or cosmic rays. No ports needed for experiment Drexel and Temple have been communicating regularly thus far Close geographic proximity allows for the teams to meet face to face and will aid in future collaboration.

17. Advisor Jin Kang, PhD. MEM Department Drexel University Team Leader Joe Mozloom Senior Mechanical Engineering Members Eric Marz Senior Electrical and Computer Engineering Linda McLaughlin Senior Electrical and Computer Engineering Swati Maini Senior Mechanical Engineering Swapnil Mengawade Senior Mechanical Engineering

18. ItemBudgeted RockSat Canister ( 1/2 can)7000 Equipment1000 In-House Testing (Drexel/Temple Facilities) In-House (0) Launch Accommodations2000 Total Budgeted$10000

20. Experiment to be used as a feasibility study of stable, despun system under high acceleration Challenges Sourcing bearings to perform under high loads/vibration of flight environment Sourcing motor(s) which are light, powerful, low voltage