TPF-I SWG Report - Exoplanet Exploration Program - NASA
TPF-I SWG Report - Exoplanet Exploration Program - NASA
TPF-I SWG Report - Exoplanet Exploration Program - NASA
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C HAPTER 6<br />
Table 6-4. Requirements of the Formation Control Testbed vs. Flight Requirements<br />
Parameter Flight Performance Formation<br />
Control Testbed<br />
Comments<br />
Number of spacecraft 5 3<br />
Operational capability<br />
Standalone operations 5 yr 36 min Total floatation time<br />
Mission duration 5 yr 5+ yrs<br />
Observational duration ~20 hr ~15 min For an “observation on the fly”<br />
Availability Continuous 8 hrs/day Ground testbed facility<br />
Motion DOFs 6 5+1 FCT:+ articulated DOF<br />
Operating envelope 3D space 2D plane FCT: with limited out-of-plane<br />
Control 2 cm / 20 arcsec 5 cm / 60 arcmin<br />
Fault recovery Active and passive None<br />
Flight capability<br />
Sensor<br />
Inertial Gyro/accel Gyro/accel<br />
Celestial Star tracker Pseudo-star tracker<br />
Relative Coarse, Med., Fine Medium<br />
Actuator Thruster, RWA Thruster, RWA<br />
Control Architecture Distributed Distributed<br />
Control Algorithms Flight Flight Developed by FAST<br />
Dynamic DOFs 6 5 FCT: +1 articulated DOF<br />
Range of motion<br />
Angular-in-plane 2π 2π<br />
Angular-out-of-plane ± 45° ± 45°<br />
Linear-in-plane<br />
Linear-out-of-plane<br />
Maneuvers<br />
Limited by sensor<br />
range<br />
Limited by sensor<br />
range<br />
Limited by lab<br />
space<br />
Acquisition 3D space 2D space<br />
Array rotation in-plane Yes Yes<br />
Array re-sizing Yes Yes<br />
Array re-targeting Yes Yes<br />
Collision Avoidance 3D space 2D space<br />
± 25 cm Emulate deadband during<br />
observations<br />
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