Instrument computers

A new computer rack has been designed and ordered to be built for the new observing system computers which are longer (deeper) than the current rack permits. The rack will replace the current rack, and all the computers and network equipment currently used as part of the observing system will be moved to the new rack. The new instrument computers will also be installed in the new rack, and at a later date the control for specific instruments will be switched to the new computers. In the new system each detector controller will be operated through a dedicated computer, while the control of all instruments will be done from one common instrument control computer. ALFOSC will be the first instrument to use this new setup and it is foreseen to solve some specific software problems seen in the current setup with the new controller.

The hardware used at ORM to write the DVDs have been substituted by more modern equipment which also speeds up the process. The plan is still to come to an automated system that would need little or no human intervention, and would use the media used to save the data more efficiently.

One issue when using the observing system remotely is that observing scripts used in remote mode suffer from time-outs. This is an effect of the way in which the instrument control software works. In particular, this software both manages the commanding of the instrument itself and the status display. When operated locally, the latter is not an issue, but when operated remotely the delay in updating the status display can cause a command to time-out though there is no problem with executing the command itself. When using the graphical user interface to operate the instrument this problem does not arise and one can operate the instrument in this way remotely (in fact, operating the instrument in this way is more instructive than using commands or scripts, so in that sense this is not an issue). However, from a general point of view the displaying of the instrument status should be something which is separate from the operation of an instrument. Beyond remote observing course, this can also be a practical issue if one thinks of possible future operations where we operate the (telescope and) instrument from a control room somewhere else on the mountain, or even from sea level. A potential problem is that the updating of the status display is embedded in the software which would make it relatively hard to change, but it is not entirely clear how much time this would take. An estimate is being made of the amount of work involved before we decide if this is worth the effort.

Thomas Augusteijn 2013-05-10