The Atacama Large Millimeter/Submillimeter Array (ALMA) is a large radio interferometric telescope consisting of 66 antennas with variable positions, to be located at the Chajnantor 5000mat a high site (5000m) in Chile. ALMA commissioning has now started with the arrival of several antennas in Chile and will continue for the next 4 years. The ALMA Software was from the beginning has been developed as an end-to-end system including: proposal preparation, dynamic scheduling, instrument control, data handling and formatting, data archiving and retrieval, automatic and manual data processing systems, and support for observatory operations. This presentation will expand mostly on ALMA software aspects issues on which we are concentrating in this phase: management, procedures, testing and validation. While software development was based on a common software infrastructure (ALMA Common Software - ACS) from the beginning, end-to-end testing was limited by the hardware available, and was possible for years until recently only on computer models. Although the control software was available early in prototype stand-alone form to support testing of prototypes antennas, it was only recently that dynamic interferometry was reached and software could be tested end to end with a somewhat stable hardware platform. The lessons learned so far will be explained, in particular the need for a realistic validation environment, the balance to be achieved between incremental development and the needed for stability and usability, and the way to achieve all the above with a development team distributed over three four continents. Some general lessons can be drown drawn on the potential conflicts between software and system (hardware) testing, or in other words on the danger in taking short-cuts in software testing and validation.

Date Published: 14 July 2008
PDF: 10 pages
Proc. SPIE 7019, Advanced Software and Control for Astronomy II, 701902 (14 July 2008); doi: 10.1117/12.787569

Published in SPIE Proceedings Vol. 7019:
Advanced Software and Control for Astronomy II
Alan Bridger; Nicole M. Radziwill, Editor(s)