VLBI Remote Control System Gonzalo Remedi and Sergio Sobarzo

Motivation Worldwide cooperation for remote operation of VLBI stations taking the advantage of the different time zones, increasing the number of observations with the same amount of staff. Fast response to error conditions.

Objectives Easy deploy over the VLBI Network –Multiplatform compatibility. Easy usage –Live display of the Log File. –Remote Operator Input. –Friendly and compact display of the main variables of the FS. –Visual indications of error conditions. Efficient use of computer resources –Minimal bandwidth need. –Minimal processor load.

Project The project was divided in 2 sections The Servers, where the data is collected, packed and sent through the Internet using TCP frames. The Clients, where the data is received, unpacked and displayed. Server stcom fscom Web Server Applet 1 Applet 2 Applet 5...

Project The servers were written in C in order to have an easy access to the FS functions and the shared memory. Servers stcom Shared Memory fscom FS variablesStation variables

Project The clients were written as Java Applets giving full compatibility over any platform. Program.java Compilation Process Program.class HTML Document Virtual Machine Virtual Machine Virtual Machine PCMACSUN

Clients

Clients

Clients

Clients

Alternative Terminal Client

FS Implementation The servers retrieve values from the FS common memory area and the station specific memory area. Proposal: Define a new standard set of common variables for FSCOM accomodating the parameters needed for remote control of a VLBI-station.

Future Work Add new key variables to the monitoring scheme (e.g. fmout-gps). Use sound as alert in the applet. Automatic comments to the log file. Extraction of the last error from the log file.

Who wants to operate TIGO during our night shifts? (We prefer to sleep!)