Perch Equal Spacing RPO Sequence

The Perch Equal Spacing RPO sequence maintains a perch point using forced-motion waypoints to maintain the current relative position. This relative position, when not on the VBar, requires station-keeping maneuvers to remain there.

This sequence uses the method of equal spacing employed by the FMWaypoints sequence to maintain this perch position. For tighter error control, you can set the Perch_MaxDegrees parameters to smaller values to ensure the maximum error from the desired perch point is small. For direct control of the error bounds, use the Perch Maximum Error RPO sequence instead.

The following picture shows a perch point, relative to the target, at +200m radial/+200m in-track/+200m cross-track for two hours with Perch_MaxDegrees set to 5 degrees. This example requires seven maneuvers and total Delta-V of 2.3 cm/sec.

Watch the following video to learn more about the RPO sequence on this page.

Sequence parameters

Option	Description
Perch_Duration	Enter the duration of the perch you want to maintain.
Perch_MaxDegrees	Enter the maximum spacecraft degrees, in angle units, between hops for the forced motion part that maintains a perch point.
Engine_Name	Enter, as a string, the name of the finite maneuver engine model.
Maneuver_Type	Select the type of maneuver, "Impulsive" or "Finite," from the drop-down list.