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Autofib 2 Fault - Lost Fibre (DE)

Description

If you can't see a fibre, the robot has dropped a fibre or the software has failed to do a centroid then below is a guide of how to recover.  It maybe that you should get guidance from an AF2 expert.

Note: you should only carry out this task if you have done it before or you are guided through the steps by somebody that has. This operation takes about one hour. The important thing is to make contact with somebody who knows and is confident to carryout this procedure, if you are at all unsure do nothing.

Try

The following steps act as a guide.

NOTE - If the inspection tv camera shows a blurred circle larger than the fibre, then the fibre has got stuck in the jaw.  In this case DO NOT FOLLOW THESE INSTRUCTIONS.  Follow the instructions on the `Fibre stuck in jaw' fault finding page instead. (coming soon - for now - see AF2 Technical manual).

Try to recover the fibre the standard way.

  1. Firstly turn the backillumination on, if not already,
  2. Try to recover the fibre,
  3. If the fibre has still not been located, it is either due to backillumination problems or collision problems.
Using the engineering terminal.
  1. It is felt safer and more reliable to enter engineering mode to recover the fibre. Use these commands carefully and do not carry out other commands unless you fully understand what you are doing.
  2. Somewhere on Taurus will be the AF2 Engineering Window (Green Window).  This 'tip' session is a direct link into the VME crate.
  3. Make sure you are in engineering mode.  If you can't see the `Engineering command >' prompt then type the following at the prompt;
  4. Once in engineering mode you must tell the system that you wish to issue commands locally.
Resolving Lost Fibre problems
  1. The next step is to make sure that the software knows which fibre is missing.
  1. The next thing you could try doing is to view the fibre that is lost.  For example Fibre 79 is lost.
  1. Try to load the fibre.
  2. If this doesn't work then you could try it again with reseting the flags
  3. If you can see the lost fibre then check the fibres either side of the lost fibre.  I.e. in this case,
  1. Assuming that the problem is only with one fibre, look to see where the fibre is.  If the fibre is in the park ring then it is safe to disable the fibre.
  1. If it isn't in the park ring (outside the field) then view the fibre again
  2. The only option left is to unfix the fibre module and to ring the lost fibre.  Before commencing with this you must park and sleep the robot.
  3. Unfixing the module is described in the "Removal of the Fibre Module" webpage.
  4. Once the module has been unfixed the lost fibre must be put in the ring position.  Then issue the following command.
  5. Engineering command > ringfibre 79
  1. If the fibre was dropped then you can load the fibre
  2. Otherwise, if the fibre has backillumination problems, so just disable it.
  3. The next step is to reset AF2.
Resetting AF2:
  1. To return the system to observering mode type the following at the engineering prompt
Now reset the AF2 ICL software by typing the following commands at the ICL prompt.
  1. Kill the af2 tasks
  2. Load and begin all af2 tasks (if not already running)
Now you are ready to try and run the setup again but remember - if you have disabled a fibre, the observer will have to disable the fibre within his configuration file.  The observer must reconfigured their field with the new version of small_fibres.dat using af2_config program.  A new copy of small_fibres.dat should be given to the observer.

If you are still having problems then call the appropiate AF2 expert.

Created by Stephen Goodsell
sjg@ing.iac.es
Last updated 9/01