R-Bar Docking [Last saved 8/2/2007.  Scenario originally created by Mike Loucks, SEE]

 

This scenario was created to demonstrate an R-Bar approach and docking of the Shuttle to the ISS.  It contains 2 satellites.

 

 

1.                   ISS                                                              This satellite is an Astrogator-propagated satellite that simulates the International Space Station orbit.

2.                  Shuttle                                                       This is an Astrogator-propagated satellite that approaches the ISS starting from 750 feet below the ISS along the Rbar.  Using autosequences to simulate an astronaut driving the shuttle along the Rbar, the satellite approaches the ISS holding to the RBar until it reaches -600 feet.  It then maneuvers to a point 400 feet in front of the ISS along the Vbar, and drives along the Vbar to the docking.  The following MCS is used:

 

The “Force to -600 Rbar” targeter moves the shuttle 150 feet up towards the ISS while holding it on the R-Bar.  The R-Bar maneuver segment starts the spacecraft in motion, and an autosequence triggered by the ‘Propagate’ segment holds the Shuttle to the Rbar until it reaches the -600 foot mark.  It holds there for 7 minutes, and then transfers via a Clohessy-Wiltshire type transfer to the Vbar.

 

Once the Shuttle reaches the ISS Vbar, it approaches via the ‘Vbar Move to Dock’ targeter.  The ‘V-Bar Maneuver’ segment starts it moving towards the ISS, and the ‘Propagate’ segment uses an autosequence again, this time to hold the spacecraft on the Vbar while it moves towards the shuttle.

 

You’ll notice that the Shuttle doesn’t actually dock, but just stops at some distance.  We could do the docking, but we’d have to make an articulation file that opened the bay doors etc.  That exercise is left for the student ;)

 

 

 

Michel E. Loucks

President, Space Mission Engineer

Space Exploration Engineering Corp. 

loucks@see.com 

360.378.7168 

360.317.5527 (cell)

www.see.com