G.Chiozzi - Report for NTT Upgrade Mission (26/11/96 -> 22/12/96)

During this mission for the NTT Upgrade Project I have worked mainly in 3 areas:

• VLT TCS Integration (mainly with Jason Spyromilio and Anders Wallander)
• Active Optics (with Lothar Noethe and Philippe Gitton)
• Auto Guiding (with Than Phan Duc)

Obviously a lot of time has also been spent in discussing and solving general problems, emergencies and bugs that do not fit directly into these categories.

A number of important pending points or things to be discussed are listed at the end of this document.

I have also provided some general support to the other people in the group regarding the TCS Interface software and more general CCS/evh matters.

On Friday 06/12/96 I gave also a general presentation to the La Silla software group on the CCS and TCS software architecture and on the usage of Object-Oriented techniques and of C++ for the development of the VLT software.

VLT TCS Integration

Part of the NTT Upgrade Project is the installation of the VLT Telescope Control Software, specifically configured to take into account the differences between the VLT and the NTT telescopes.

Up to this point the attention was concentrated mainly on the hardware and low level components and only minor efforts have been spent on integrating the Workstation Coordination modules.

The main task of my mission was to perform this integration getting working the high level coordination software.

At the end of my mission this modules have been working for a few days without interruption and without showing major problems. Obviously there are still a number of known minor ones, limitations or not yet implemented features.

• Analyzed process distribution between wt5tcs (Telescope Control WS) and wa5tcs (Acquisition and Guiding WS). For TCS architecture reasons, all TCS WS processes must run under the same RTAP environment. As a consequqnce also agwscontrol, actconControl and related processes will be on wt5tcs. The CCD processes will run instead on wa5tcs (29/11/96). This has been implemented without major problems and now the 2 machine are much cleaner.
• Fixed a number of inconsistencies in the handling of setup files, dictionaries and alias tables (04/12/96).
• Extended change focus procedure. Now Mode Switching asks M3 at init time for its position to determine the real focus station. The procedure is not complete and more steps need to be added (06-08/12/96).
• Improved handling of TCS Mode Switching global state commands, removing dead lock conditions and making change state procedures reliable. This has involved also a better configuration of the the Mode Switching configuration table for the NTT.
• A lot of time has been spent in analyzing and configuring the Preset sequence for the NTT. This is one of the most complex (from the logical point of view) functions and requires a lot of changes and rething. We should evaluate again the original idea (see the Design Description) of implementing it via a Sequencer script.

Active Optics

Another major activity has been to work with Lothar Noethe and Philippe Gitton to get Active Optics working. They were working primarly on the algorithmic part and I have worked mainly on the general architecture of the modules involved and provided support for the implementation.

• General clean up of the modules (28-29/11/96).
• Setup test environment to verify Active Optics functionality feeding the CCD software with test images. This can be used also to setup automatic modular tests (01-03/12/96).
• Built MIDAS procedures to display plotsof the data produced (01/12/96).
• Built new panels for AO control and modified the existing ones to be of more general use. Made them independent from hard-coded configuration parameters.
• One of the major changes to the modules consisted in moving on the Real-Time database all configuration parameters, that were before hard-coded in the source files. This required a major restructuration of the sorftware.
• Tested active optics on the real sky, first just to evaluate the correction terms and then appliyng corrections to the mirrors. The whole chain has been tested and is working (presetting, taking the image, calculating the corrections, applying them) in automatic loop mode.
• Patched the Telescope Interface Module (tif) to implement missing featured (17/12/96).

Auto Guiding

I have also worked with Than Phan Duc to integrate the workstation and LCU components of the Auto Guiding system and to make the first tests.

• Rebuilts the modules and verified the interfaces
• Fixed minor bigs and implemented some missing features (like the handling of the 2 focus stations).
• Testing on the sky. The basic principle is working, but the image analisys for the calculation of centroids for the error vectors is not good enought and will have to be improved.
• I should have worked on the error vectors algorithm and on other missing points, but I had to spent all my time on the other 2 points, that had higher priority.

General Problems

• Fixed a very important bug on evh for the evhDB_CMD_SERIAL class. This took almost 2 days of work (15-16/12/96).

Pending points and arguments to be discussed

• Active Optics modules still requires a final clean-up to make them more maintenable.
• Auto Guiding need some more work, mainly for what concern error vector calculation. Some work is also necessary for what concern the handling of the rotator and of the adapter. This will be done by Than.
• We have found very valuable the possibility of feeding the CCD software with "syntetic" and test images, i.e. images not acquired by the CCD chip but stored on files. This is very usefull to perform automatic and regression tests. These CCD commands are considered only "internal" commands and are not documented, while they should be.
• Mode Switching change focus procedure is not yet complete.
• The Mode Switching COLD START command is crytical, since there are preconditions to be checked before it can be executed. For example the hydraulics and the building must be already online. In order not to make too complex the MSW module and having at the same time an easy implementation/configurability of these checks, we have agreed on implementing a sequencer check function, to be called by msw. It has to return "OK" if the preconditions are fullfilled or a proper error message if not, like: "ERROR - Please put ONLINE building module". This error will be reported to the user.
• The Preset sequence required a lot of reworking. The same will happen on the VLT. We should re-examine the original idea (see the Design Description) of implementing it via a Sequencer script.
• It has been pointed out that the Talescope Interface module does not provide a Sequencer API. It is my opinion that there should be one.
• There have been a number of discussions on Setup File handling (14/12/96, 18/12/96)
• The patches introduced on the Telescope Interface Module (tif) must be replaced with the actual final implementation.
• We had also an important discussion Important discussion with Jason and Paul on how tif handles commands during calibration when an instrument is not on the light path. The current implementation accepts a subset of specific commands directed to the adapter/probe /rotator of the corresponding focus. In the final system the booking software will take care of blocking commands directed to the prs, trkws and other control modules when the tif is not the one of the current focus station. The commands acceptd when not on the light path are a specific set of commands. A generic SETUP command will be rejected, since it would be redirected to PRESET and not to an adapter/rotator. This implies that the procedures to be used for calibration out of focus must be in general not the same used when on the light path. For example all commands in sky coordinates are no allowed. This is considered enought and corresponding to what specified in the ICD, but it will have to be clarified if there are other needs from the INS side.

For more details on the activity performed
you can have a look at the collection of my
daily logs.

Last modified: Thu Dec 30 15:01:43 MET 1999