2. Agenda
Mission
Concept of Operations
Technology
Amateur Radio Tie-Ins
3. Mission - Goals
Test a new ion engine design
Electrostatic
principles
Pulsed plasma generation
Exhaust flow beyond classic Child-Langmuir limit
Increased thrust per [kg, m3]
(future) Alternative plasma generation method
Lower power requirements
(new) Alternative fuel storage
Lower complexity for gas-based thrusters
4. Mission – TubeSat Standard
127mm
tall
500 grams + 250 grams payload
Images: Interorbital Systems
5. Mission – TubeSat Orbit
310 km polar sun-synchronous orbit
Decaying, 3-12 weeks
90.7 minute orbit period
Launch by
Interorbital Systems
interorbital.com
Image: Interorbital Systems
6. Mission - Thermal
Average temperature, °C
PCB Material Metal Strips Hot Case Cold Case
Green PCB Aluminum, polished 95 -7
Green PCB Aluminum, anodized 68 -18
White PCB Polished copper 89 -7
White PCB Carbon black paint 84 1
White PCB Aluminum, polished 84 -19
White PCB 3M Black Velvet paint 83 1
White PCB Anodized black metal 81 -1
White PCB Gray paint 77 -6
White PCB Aluminum, anodized 57 -28
16. Technology - Microprocessor
SEU current sensor
Shielding?
Image: http://www.aero.org/publications/crosslink/winter2000/03.html
17. Technology - Engine
Electrostatic
Child-Langmuir limit
to fuel flow
Fuel flow limit
to Thrust density
Use lasers to get
past classic limits
Low thrust confuses
sensors
18. Technology - Fuel
Nitrous oxide cylinder
Lotsof fuel
Not ConOps friendly
Closed cell foam
Easy storage – ConOps
Semi-untested in space
Pulsed Plasma Thruster
Wide variety of fuel species
Energy intensive Overview of PPT operation. (1) Energy
storage unit. (2) Ignitor. (3) Fuel rod.
(4) Plasma acceleration Credit: NASA
Images: http://www.lelandltd.com/mini_cartridges.htm
http://www.nasa.gov/centers/glenn/about/fs23grc.html
20. Technology – Attitude Sensing
9 DOF & Temperature
Kalman filter
1.3 grams
45mA @ 5V
0.225 W
Open question:
Will Kalman filter out
our engine’s effects?
http://tech.yostengineering.com/3-space-sensor/product-family/embedded
21. Technology – Attitude Control
Active Magnetorquer
High Power
High Price
Image: ISIS Magnetorqer, http://www.cubesatshop.com
22. Technology – Attitude Control
Passive magnetic attitude control
Permanent magnet
Hysteresis rods
- Slow convergence
- Large fraction of payload space for rods
Images: http://www-personal.umich.edu/~mjregan/MCubed/Pages/O&C.html
http://cosmiac.ece.unm.edu
23. Technology – Attitude Control
Piezoelectric Energy Harvesting
Kinetic and spring energy to electrical energy
- New approach
- Dampens vibration
- Dampens rotational acceleration using lever arms
Images: http://piezo.com/prodproto4EHkit.html
24. Amateur Radio Tie-Ins
Store and forward message(s)
Compressed Sensing telemetry
AX.25 Relays
Other ideas?!