Path: FormationFlying/Control
% Computes a delta-v sequence for a relative orbit maneuver in a circular orbit
- A constant thrust is assumed when converting delta-v to burn duration.
- Algorithms do not account for gravitational perturbations or disturbances.
- A circular reference orbit is assumed.
- The delta-v sequence is determined from a closed-form solution, derived from
Gauss' variational equations.
--------------------------------------------------------------------------
------
Inputs
------
state (.) Data structure of the orbit state with following fields
- el Measured mean orbital elements of reference [a,i,W,w,e,M]
- elA Alfriend format of elements [a,lat,i,q1,q2,W]
- xH Measured Hills-frame state: [x;y;z;xdot;ydot;zdot]
- mass Spacecraft mass [kg]
- tM Timetag of measurement [sec]
goals (.) Data structure of geometric goal information.
Describes the desired trajectory.
window (.) Data structure of commanded time window with following fields
- startTime Earliest possible start time [sec since 1970]
- nOrbMin Minimum number of orbits maneuver may last [orbits]
- nOrbMax Maximum number of orbits maneuver may last [orbits]
- nManeuvers Number of maneuvers to search over
- timeWeightExp Time-weighting exponent (greater than 0)
parameters (.) Data structure of planning parameters with following fields
- fNom Nominal Thruster force [kN]
- dTMax Maximum allowable burn duration [sec]
- horizon Minimum time between planning and first burn [sec]
- tDelayOOP Minimum time between final IP burn and OOP burn [sec]
- nSPOCoarse Number of samples per orbit for LP (coarse computation)
- nSPOFine Number of samples per orbit for LP (fine computation)
-------
Outputs
-------
maneuver (.) Maneuver data structure with following fields
- t0 Earliest burn start time
- tF Latest burn finish time
- nBurns Number of burns required
+ burnData[] Array of burn data structures with following fields
- t Burn start time [sec since 1970]
- dT Burn duration [sec]
- dV Delta-V [km/s]
- uX unit x Hills direction
- uY unit y Hills direction
- uZ unit z Hills direction
maxDV (1) The maximum delta-v of the sequence
--------------------------------------------------------------------------
References: Mueller, J. and M. Brito,"A Distributed Flight Software Design
for Satellite Formation Flying Control," presented at the AIAA
Space 2003 Conference, Long Beach, CA, September 2003.
--------------------------------------------------------------------------
FormationFlying: Control/InPlane FormationFlying: Control/OutOfPlane FormationFlying: Coord/InitializeFormation FormationFlying: DataStructures/Maneuver_Structure FormationFlying: Dynamics/DiscreteHills FormationFlying: Dynamics/HillsEqns FormationFlying: Guidance/PCGoals FormationFlying: Transformation/Goals2DeltaElem FormationFlying: Transformation/Hills2DeltaElem FormationFlying: Utility/ManeuverStruct2AccelVector FormationFlying: Utility/NOrbVector FormationFlying: Visual/HillsFramePlot Orbit: OrbitCoord/Alfriend2El Orbit: OrbitCoord/El2Alfriend Orbit: OrbitCoord/SLR SC: BasicOrbit/El2RV SC: BasicOrbit/OrbRate Math: Linear/Mag
Back to the FormationFlying Module page