Difference between revisions of "Orbital rendezvous"

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The process of creating an encounter with a target object requires the player to meet two conditions.  The first is that the orbit of the craft must intersect the orbit of the target (this is usually tangential for efficiency).  The second is that both craft and target must be at the intersection at the same time.  
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The process of creating an encounter with a target object requires the player to meet four conditions.  The first is that the orbit of the craft must be in the same orbital plane as the target.  The second is that the orbit of the craft must intersect the orbit of the target (this is usually tangential for efficiency).  This can be from a lower orbit where you will be travelling at a slower velocity, or from a higher and faster orbit.  The third is that both craft and target must be at the intersection at the same time. Finally, the craft and the target must match velocities.  For low planetary orbits, it is easier to approach the target from a higher more elliptical orbit where you are initially in front of the target and your orbit slows your craft.  For higher planetary orbits it is faster to approach from a lower orbit from behind.  Your velocity will be slower but your orbital period will be shorter.  Low planetary orbits take little time and allow many trial and error attempts.  High orbits, especially solar orbits, mean days, months or years between passes, so planning is important.  With practice, your craft can come from an oblique orbit at a vastly different velocity to intercept the target, changing plane and velocity in a single manoeuvre for a spectacular rendezvous!!  Chasing asteroids, for example, or crash diving into a moon's SOI for ship to ship docking. 
  
 
Often only one craft does the orbital maneuvers and the other object is passive and does not change its orbit.
 
Often only one craft does the orbital maneuvers and the other object is passive and does not change its orbit.

Revision as of 09:34, 18 January 2017

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An Orbital Rendezvous is a series of maneuvers which result in a craft achieving a stable condition of close proximity to a target object orbiting the same parent body.

In general, an orbital rendezvous involves two steps - encounter and velocity matching.

Usages

Possible usages of orbital rendezvous include:

Encounter

The process of creating an encounter with a target object requires the player to meet four conditions. The first is that the orbit of the craft must be in the same orbital plane as the target. The second is that the orbit of the craft must intersect the orbit of the target (this is usually tangential for efficiency). This can be from a lower orbit where you will be travelling at a slower velocity, or from a higher and faster orbit. The third is that both craft and target must be at the intersection at the same time. Finally, the craft and the target must match velocities. For low planetary orbits, it is easier to approach the target from a higher more elliptical orbit where you are initially in front of the target and your orbit slows your craft. For higher planetary orbits it is faster to approach from a lower orbit from behind. Your velocity will be slower but your orbital period will be shorter. Low planetary orbits take little time and allow many trial and error attempts. High orbits, especially solar orbits, mean days, months or years between passes, so planning is important. With practice, your craft can come from an oblique orbit at a vastly different velocity to intercept the target, changing plane and velocity in a single manoeuvre for a spectacular rendezvous!! Chasing asteroids, for example, or crash diving into a moon's SOI for ship to ship docking.

Often only one craft does the orbital maneuvers and the other object is passive and does not change its orbit.

Velocity Matching

Once the craft is in close proximity to the target, a maneuver is made to match velocity with target, thus matching orbits. When relative velocity is null, a more or less stable situation exists. The player can then EVA to the target, dock with the target (if craft and/or target are properly equipped), or perform any task which requires the craft to remain in close proximity to the target.

Tutorials

Several tutorials exist which can help the player learn the process of orbital rendezvous. As of version 1.0, there is also an ingame tutorial.