Embed Size (px)
DESCRIPTION
FRETS1 satellite project, including a custom ion engine, presented to the Hazel Park Amateur Radio Club (HPARC) on 2012-02-08.
Citation preview
FRETS1 SATELLITE
Presented at HPARC, 2012-02-08
Agenda
Mission
Concept of Operations
Technology
Amateur Radio Tie-Ins
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
Mission – TubeSat Standard
Images: Interorbital Systems
500 grams + 250 grams payload
127mm
tall
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
Mission - Thermal
Average temperature, °CPCB 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
ConOps – Launch Operations
Wait
Launch
Coast
Release
Wake
Initialize
ConOps – Orbit Operations
Safe
Engine baseline experiments
Engine effect experiments
Sensor experiments
Mechanical experiments
Energy gathering
Communication relay
Status reporting
ConOps – End of Mission Ops
Orbit decay
Reentry
Technology - Communications
MX614
AX25
Encoder
PIC
AX25
Decoder
PIC Transceiver
433MHz band
100mW
Radiometrix
Amplifier
500mW
Radiometrix
Main
CPU
BasicX 24
Technology – Comm. Board
Technology - Solar
48 solar cells
8 strips of 6
Technology - Solar
Radial
0.75 Watt avg.
on sun side
Flat/Bullet
0.75 Watt avg.
on sun side
Sun Seeker
1.18 Watt avg.
on sun side
Technology - Power
Voltage
Regulator
Li-Ion
Battery
3.7V
5200mAh
8 Current
Sensors
Deployment
Switches
Step-Up
Voltage
Converter
CPU
Board
Comm.
Board
Engine
Board
8 Channel
ADC
4.2V5.7V
Diodes
SPI
Technology - Microprocessor
BasicX-24
I2C interface
IMU
Flash memory
SPI Solar ADC
Images: http://basicx.com/
Technology - Microprocessor
SEU current sensor
Shielding?
Image: http://www.aero.org/publications/crosslink/winter2000/03.html
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
Technology - Fuel
Nitrous oxide cylinder
Lots of 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: NASAImages: http://www.lelandltd.com/mini_cartridges.htm
http://www.nasa.gov/centers/glenn/about/fs23grc.html
Technology – Attitude Sensing
9 DOF
HMC5883L magnetometer
ADXL345 accelerometer
ITG-3200 gyro
I2C interface
1.0 gram
Manual correction for
drift and noise required.
http://www.sparkfun.com/products/10183
Technology – Attitude Sensing
9 DOF & Temperature
Kalman filter
1.3 grams
45mA @ 5V
0.225 W
http://tech.yostengineering.com/3-space-sensor/product-family/embedded
Open question:
Will Kalman filter out
our engine’s effects?
Technology – Attitude Control
Active Magnetorquer
High Power
High Price
Image: ISIS Magnetorqer, http://www.cubesatshop.com
Technology – Attitude Control
Passive magnetic attitude control
Permanent magnet
Hysteresis rods
Images: http://www-personal.umich.edu/~mjregan/MCubed/Pages/O&C.html
http://cosmiac.ece.unm.edu
- Slow convergence
- Large fraction of payload space for rods
Technology – Attitude Control
Piezoelectric Energy Harvesting
Kinetic and spring energy to electrical energy
Images: http://piezo.com/prodproto4EHkit.html
- New approach
- Dampens vibration
- Dampens rotational acceleration using lever arms
Amateur Radio Tie-Ins
Store and forward message(s)
Compressed Sensing telemetry
AX.25 Relays
Other ideas?!
