Impulse Maneuvers¶

Impulse maneuvers model instantaneous delta-V burns triggered by g-function zero-crossings during propagation. Each maneuver defines its own event function and firing condition.

ImpulseManeuver (Abstract)¶

Member	Description
`ComputeEventValue(StateVector)`	Scalar g-function evaluated at the current state
`EventCrossingDirection`	`CrossingDirection` that triggers the burn
`CheckPreconditions(StateVector)`	Optional additional constraints (returns `true` to allow firing)
`DeltaV`	Burn delta-V vector in the maneuver frame

Concrete Maneuvers¶

ApogeeHeightManeuver¶

Raises apogee height. Fires at perigee (r . v crosses zero from negative to positive).

PerigeeHeightManeuver¶

Raises perigee height. Fires at apogee (r . v crosses zero from positive to negative).

PhasingManeuver¶

Adjusts orbital period for phasing. Fires at perigee (r . v, negative to positive).

CombinedManeuver¶

Combined plane and apsis change. Fires at apogee (r . v, positive to negative) with an additional precondition that the apogee is aligned with the ascending node.

PlaneAlignmentManeuver¶

Changes orbital plane to match a target. Uses an adaptive crossing direction on the g-function r . h_target to fire at the nearest orbital node (ascending or descending).

ApsidalAlignmentManeuver¶

Rotates the line of apsides. Fires at the nearest orbit intersection point using the g-function r . (h x p) with negative-to-positive crossing.

Maneuver Chain¶

Maneuvers are linked in a chain on the spacecraft:

Leading attitudes execute immediately at the initial state.
The first ImpulseManeuver is wrapped in a ManeuverEventDetector.
When the event fires, the burn is applied and the chain advances to the next impulse maneuver.
The process repeats until all maneuvers in the chain have executed.

Example¶

var maneuver = new ApogeeHeightManeuver(
    Time.J2000TDB,
    TimeSpan.FromSeconds(0),
    targetApogee: 42164000.0,
    engine, fuelTank);

spacecraft.SetStandbyManeuver(maneuver);
var solution = spacecraft.Propagate(window, perturbingBodies, false, false, deltaT);