180 likes | 312 Vues
Contractor 3. AsteroidGazer (AG) Design Review. Mission Overview. III. Formation Alignment with Star Pictures Data downlink Stationkeeping. II. Deployment. IV. Deorbit. I. Launch. Design Overview. Twelve 3U cubesats External, deployable telescope feature
E N D
Contractor 3 AsteroidGazer (AG) Design Review
Mission Overview • III. • Formation • Alignment with Star • Pictures • Data downlink • Stationkeeping II. Deployment IV. Deorbit I. Launch
Design Overview • Twelve 3U cubesats • External, deployable telescope feature • Thruster and Attitude control system • Solar and battery power • Ability to individually transmit data to ground • Circular formation for maximum resolution
Phases I and IILaunch and Deployment Pegasus XL – Orbital Sciences Cape Canaveral, FL : Latitude 28°N Launch due East i=28°
Formation Design Line Circle Concentric Circles Y Shape Plus Sin Wave
Formation Design • Decided to focus formation on detecting NEAs with 140 m diameter. • The equally spaced circle formation provided an acceptable maximum number of pixels
12 Cube Sat Solution Resolution = 250 meters
Configuration Design 3U Cubesat Components Optical System Camera System Solar Panels Attitude Control System Battery System Propulsion System
Components • Power System • Solar panels • Batteries • Communication System • Transmitter • Antenna • Propulsion System • Thrusters • Attitude System • Attitude Determination & Control System • Optical System • Telescope parts • Camera
Power • Primary Power Source: Solar Panels • High quality PCB substrate & Kaptonoverlay. • Generate up to 1 Watt of power each • Number of panels is dependent power required and space available • Backup Power Source: Lithium-Polymer Batteries • High energy density • Previous success on satellites • Battery size is dependent on power required (150 Watt-hour per kilogram)
Power • Regulator: EPS board • Will regulate and monitor power generated. • Under-voltage and over-current protection. • Distributor: Power Distribution Module • Will distribute power to all components in the Cubesat. • Under-voltage and over-current protection.
Communications • Calculated data rate of 80 kb/s. • Estimated fly over GS time of 7 min. • Individual communication of each satellite with ground station. • S – Band Transmitter • 2 mb/s data rate • S – Band patch antenna
Propulsion • Large maneuvers: Pulse Plasma Thruster • Delta V = 250 m/s for mission duration • Typical shot energy 1.8J • Mass <200g including 10g of propellant • Copper Tungsten electrode provides durability • Power draw of less than 0.5W • Specific impulse measured at 590s
ADCS Blue Canyon Technologies XACT Fully integrated solution: • 3 axis stellar attitude determination • 3 Reaction Wheels • 3 torque rods • IMU • Magnetometer • Sun sensors • Computer
Optics and Detectors • Cassegrain Reflector • primary concave mirror • secondary convex mirror • CCD (Charge-Coupled Device) Detector • CCD 595 from Fairchild Imaging • Designed for space applications • 9216 x 9216 full frame CCD array