Astronomy omp
Joint Centre James Clerk Maxwell Telescope United Kingdom Infrared Telescope
T. Jenness
1st August 2001
JAC O BSERVATION M ANAGEMENT P ROJECT 7.1
Towards a unified observing manager
Contents
1 ORAC-OM 1.1 Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OMP-OM 2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Observation Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Telescope differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 2 2 3 5
2
1
ORAC-OM
This section provides a small introduction to the ORAC-OM in use at UKIRT. This background is necessary so that we can discuss the OMP-OM requirements within that framework. The ORAC-OM provides the following functionality: Retrieval of a science program from a remote database (the ODBSvr). Selection of a particular observation from within a science program. Translation of the observation object to low level instrument and telescope control format Sending of this translated observation to the sequencer (there is one sequencer for each instrument) A sequence console allowing the observer to control the sequencer and display the state of the sequencer. This uses DRAMA commands and monitors. The ability to control which instrument currently is in control of the telescope.
OMP/SN/007
2
The ability for a second version of the sequence console to be created which can be configured to take control of the main console. This allows the TSS to prevent the observer from moving the telescope unexpectedly. The ORAC-OM is described in more detail in ORAC1 document orac018.
1.1
Technology
The ORAC-OM consists of two parts. The main system is written in Java using a SWING GUI, with database connectivity implemented using RMI. DRAMA messaging is implemented by opening a socket to a special C DRAMA task; the socket is used to send an receive DRAMA messages. The Java GUI is not involved in DRAMA messaging directly. The main program registers itself as an RMI server. The second (TSS) console is created by connecting to that server and retrieving serialised objects containing the GUI and messaging information. The TSS console is therefore an exact replica of the main window. The translator is a Java object used from within the ORAC-OM. It is not technically a separate part of the ORAC-OM although the interface is simple enough that it is not entwined in the ORAC-OM.
2
OMP-OM
This section describes the new observing manager required for the Observation Management Project (OMP).
2.1
Overview
The OMP observing manager must provide similar functionality to the above along with the querying functionality described in OMP/SN/004. Whereas the ORAC-OM works in terms of science programs and observations the OMP-OM only deals in Minimum Schedulable Blocks (MSBs). Additionally, the OMP-OM must be implemented such that it will function on both the UKIRT and the JCMT. Only two parts of the ORAC-OM are relevant for the OMP. These are the translator and the sequence console. The science program retrieval window must be replaced and the database retrieval modified to work with MSBs and also to fit into the standard OMP SOAP framework. The translator and sequence console are clearly telescope specific and in order to simplify support and clearly demarcate generic OMP code from telescope specific code the OMP-OM will physically separate these units. This means the OMP-OM will itself just consist of the database query system, the MSB queue (this is the queue of observations within an MSB) and possibly an observation editor (to provide a means for tweaking observations just before translation; exposure time is the usual example). The translator will be a separate external object controlled using SOAP. Each telescope will run a different translator but will meet the standard interface (in principal this is XML as input and translated filename as output).
1
http://www.jach.hawaii.edu/JACpublic/UKIRT/software/orac/
OMP/SN/007
3
The sequence console will be wholly separate from the OMP-OM and will be different for each telescope. There will be no interaction between the OMP-OM and the sequence console(s) except, possibly, for the initial launching of the first console. The overall design can be seen in figure 1.
2.2
Observation Management
The role of the OM is to enable the observer to select the best observation and send it to the telescope and instrumentation. This section takes a detailed look at this process as envisaged by the OMP. It focuses mainly on observation handling rather than observation selection. For more details on the latter see OMP/SN/004. Once an MSB has been selected by the observer it is loaded into the MSB queue screen. This first of function this screen is to allow the observer to remove or store calibration observations if it is necessary to do so (and if the Principal Investigator has allowed this). Once the MSB is ready for for observing, the observer will be able to start processing the queue. Since translation may require knowledge of current telescope position (say, in order to dynamically calculate the best pointing source2 ) or quantities that are changing with time (for example, automatic determination of exposure time given specific weather conditions) it is prudent to delay translation of a particular MSB component until the telescope is ready for it. Each observation is therefore not sent for translation until the previous observation has completed. This step will either be automatic (observations are sent for translation without further interaction by the observer) or manual (the observer will have to explicitly send each component) depending on the telescope requirements (on JCMT this will almost certainly be automatic by default). As each observation is completed by the sequencer3 , the next observation is translated and sent and the highlight moves down the list to indicate the progress of the MSB. Once the observation is translated the sequencer will be instructed to load the translated observation using a DRAMA message (launching the sequencer for the particular instrument if required). At this point a sequence console will be loaded4 . The sequence console will automatically detect how many sequencer are running and configure itself accordingly. Each sequencer will be a tabbed frame that can be selected by the observer. In order for the observer to be aware of changes in state of a particular sequence the tab associated with an instrument sequencer will change color when a DRAMA monitor is received for it. The color will revert to normal once it has been raised to the front. Finally, the console window will also have a beam selector menu that will allow the observer to specify which of the instruments will be allowed to control the telescope. Each console will be completely independent of the others, allowing any number of consoles to be launched at once. For example, a support scientist from Hilo would be able to monitor the sequence without affecting the observer or TSS. Since the consoles are independent the first version of the new standalone sequence console will not include the ability for the TSS to take control of the telescope unless this is deemed a priority. Once the last observation in a particular MSB has been sent for execution, the MSB database will be updated to reflect this. Note that if we are receiving completion status from the sequencer we could
This will require knowledge of the target that follows this pointing. How is the translator going to know? Does the pointing description include a reference to details of the science target? 3...