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CINEMA Orbit/Attitude?. Spin Plane. Satellite flight path questions:. Flight Path. Flight Path. Or. Earth. Spin Plane. Earth. Flight Path. Side View? Or, rotate the body by 90 degree along the long axis?. Zenith View (looking down from top toward earth).
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CINEMA Orbit/Attitude? Spin Plane Satellite flight path questions: Flight Path Flight Path Or Earth Spin Plane Earth Flight Path Side View? Or, rotate the body by 90 degree along the long axis? Zenith View (looking down from top toward earth)
CINEMA Propulsion System (mechanical) Cold Gas Propulsion System (mechanical): Propellant- Propellant: 1,1,1,3,3,3-hexafluoropropane Nominal Isp: 47s Installed Isp: 40s Nominal propellant pressure: 272.32 kPa @ 25C System- Number of units required per satellite: 3 Nominal unit size: 8cm x 8cm x1 cm (can be tailored) Total mass per unit: 100 grams Propellant mass per unit: 30 grams Nominal thrust per nozzle: 10 mN Minimum thrust impulse: 10µN-s Satellite Performance- Total mission delta-V: 3.6 m/s P-Pod delta-V correction: 2m/s Available mission delta-V: 1.6m/s Required delta-V: 0.0116 m/s-per day (assumes 1km/day drift) Expected delta-V: 0.0327m/s-per day (assumes nozzle design and 3D drift w.r.t. each satellite) Minimum Correction thrusting time: 3sec-per day Expected mission endurance: 7 weeks
CINEMA Propulsion System (electrical) Cold Gas Propulsion System (electrical): Electronic System- Control processor: PIC16 or PIC18-class Rate gyroscopes: ADXRS300 rate gyros x 3 Temperature sensor: Thermistor (in propellant tank) Pressure sensor: MEMS (in propellant tank) Power- Electronic system voltage: 5V Maximum electronic system power: 150mW (thrust operation) Minimum electronic system power: 25mW (non-thrust operation) Thruster valve voltage: 12V Maximum thruster power: 1W (2 switched on, 5-10 seconds per day) Heater power: depending on nominal satellite temperature, zero if ~20-25°C Knowledge- Position: need position relative to each CINEMA satellite, can use magnetometer? Radio signal strength? Attitude: from CINEMA ADACS Communication- Protocol: RS-232 or I2C
CINEMA Propulsion System Configuration Thruster unit only needs two thin slits (~1-2mm) for the nozzles. External devices can be mounted to it simply by accommodating these slits. Each unit is centrally mounted on each long face except on the side with the magnetometer boom aperture. 8cm x 8cm x 5cm (can be tailored) Thruster Nozzle Slit Thrust Lines (slight offset from line to CG) Thruster Unit CG Delivery Date- Optimistically: End of May 2010 Drop Dead: End of August 2010
Exposed and baked nozzle layer Etched nozzle and valve layers with valves
Assembled Propulsion Module • 300 g mass (dry) • Freon propellant • HFC 236fa • On-board gyro Magnetometer MEMS Gyro Transceiver The Aerospace Corporation
View from the Bottom Vapor/Liquid Seperator Temperature Sensors Heater Coil