Computes the delta-v's required to implement a formation flying maneuver for
   a single spacecraft. The desired relative state is iteratively recomputed,
   bringing the desired state closer to the current state, until the 
   largest single delta-v in the maneuver is under the maximum limit.

   A fixed thrust actuator is assumed when converting delta-v to burn duration.
   Algorithms do not account for gravitational perturbations or disturbances.

   Since version 7.
   [maneuver, foundSoln, resetGoals] = IterativeImpulsiveManeuver( state, goals, window, parameters );

   state             (.)  Data structure of the orbit state with following fields
                          - el           Measured mean orbital elements of reference, Alfriend format: [a,i,W,w,e,M]
                          - xH           Measured relative state in Hills frame
                          - mass         Spacecraft mass                              [kg]
                          - tM           Timetag of measurement                       [sec]

   goals             (.)  Geometric goals describing desired relative periodic 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)
                          - maxDeltaV    Maximum delta-v

   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
   foundSoln         (1)  Flag indicating whether a solution was found or not
   resetGoals        (1)  Flag indicating whether the goals were reset or not


FormationFlying: Control/ImpulsiveLPManeuver
FormationFlying: Control/ImpulsiveManeuver
FormationFlying: Coord/IsCircGeom
FormationFlying: Coord/IsEccGeom
FormationFlying: DataStructures/PlanningParameters_Structure
FormationFlying: DataStructures/Window_Structure
FormationFlying: Guidance/PCGoals
FormationFlying: Transformation/FFEccGoals2Hills
FormationFlying: Transformation/FFEccHills2Goals
FormationFlying: Transformation/GeometryCirc2Ecc
FormationFlying: Transformation/GeometryEcc2Circ
FormationFlying: Transformation/Goals2Hills
FormationFlying: Transformation/Hills2Goals
FormationFlying: Utility/NOrbVector
Orbit: OrbitCoord/El2Alfriend
OrbitMiniToolbox: Support/M2Nu
SC: BasicOrbit/OrbRate