Designing Control System Software for Radio Telescopes S. Chaudhuri, A. Ahuja, S. Natrajan, and H.M. Vin Presenter: Harrick M. Vin Vice President and Chief Scientist Tata Research Development and Design Centre, Tata Consultancy Services (TCS) S. Chaudhuri, A. Ahuja, S. Natrajan, and H.M. Vin Presenter: Harrick M. Vin Vice President and Chief Scientist Tata Research Development and Design Centre, Tata Consultancy Services (TCS)

November 2008 TCS CONFIDENTIAL Control System Software for Scientific Apparatus GMRT Radio Telescope [In collaboration with NCRA, Pune] International Thermo-nuclear Experimental Reactor (ITER) [In collaboration with IPR, Ahmedabad] Design of command-and-control environment for complex, scientific apparatus Collect and analyze data streams from a large network of sensors Control apparatus operations through actuators Two Interesting Projects 2

November 2008 TCS CONFIDENTIAL Requirements and Opportunities Solution requirements Agility – Rapid development of software control system Configurability – Ease of building custom enhancements Evolvability – Evolve systems to accommodate new technologies Broader requirement Reusability – Reuse the framework across different apparatus Common practice One-off custom-built software control systems Design and implementation takes too long Too much custom coding  Not very configurable Significant changes required to accommodate changes Definitely not reusable 3 Requirements

November 2008 TCS CONFIDENTIAL Vision and Approach Reusable, evolvable and configurable control software framework Specification-driven architecture  Automate code generation Dramatically reduce effort and cost Vision What are the “common” abstractions? Is there a generic architecture for control system software? Key questions Model scientific apparatus as a network of sensors and actuators Develop a flexible architecture for control element Capture interactions with sensors and actuators Model complete system as a composition of control elements Approach 4 Vision and Approach

November 2008 TCS CONFIDENTIAL Sensor-Actuator Control Element (SACE) 5 Data & Event Distribution Data & Event Distribution Data Acquisition Data Acquisition Data Processing Data Processing Data Streaming Data Streaming Validation Rules Validation Rules Command Translation FSM, Script, Rules Command Translation FSM, Script, Rules SACE Configuration SACE Configuration Subsystem Self Description Subsystem Self Description SACE Architecture Event Reception Event Reception Event Processing Event Processing Event Notification Event Notification Command Distribution Command Distribution Command Processing Command Processing Command Reception Command Reception

November 2008 TCS CONFIDENTIAL Software Control GMRT Using SACE 6 GMRT

November 2008 TCS CONFIDENTIAL Sensor-Actuator Control Element (SACE) 7 Data & Event Distribution Data & Event Distribution Data Acquisition Data Acquisition Data Processing Data Processing Data Streaming Data Streaming Validation Rules Validation Rules Command Translation FSM, Script, Rules Command Translation FSM, Script, Rules SACE Configuration SACE Configuration Subsystem Self Description Subsystem Self Description SACE Architecture Event Reception Event Reception Event Processing Event Processing Event Notification Event Notification Command Distribution Command Distribution Command Processing Command Processing Command Reception Command Reception Real-time visualization

November 2008 TCS CONFIDENTIAL SACE Prototype Implementation Philosophy: Leverage third-party components as much as possible Technology choices: –Basic platform: Java –System specification format: XML –Command validation and translation: Unimode FSM Framework OpenRules rules engine –Interpreter for configuration and control scripts: Mozilla Rhino –Data stream processing: HSQLDB, Hibernate (in-memory DB) –Communication: TCP/IP sockets –Driver integration: Java Native Interface (JNI) –Auto-generation of UI: Swing –Data stream visualization: JFreeChart 8 SACE Implementation

November 2008 TCS CONFIDENTIAL SACE GMRT Existing control system software: ~15,000 lines of code ABCCom – running at individual GMRT antennas Teleset – running at Central Building SACE-based control system software Reuse about 50% of code of ABCCom (~3,000 lines of code) Drivers for interaction with hardware devices Replace the rest of ABCCom and Teleset with SACE-geenrated code ! Benefits Flexibility, Evolvability and Configurability Reuse 9 GMRT

For more information, contact: Harrick Vin

November 2008 TCS CONFIDENTIAL IF Subsystem: Self Description 11 GMRT

November 2008 TCS CONFIDENTIAL Data Validation Using Rules 12 GMRT

November 2008 TCS CONFIDENTIAL IF Command Validation and Translation 13 GMRT

November 2008 TCS CONFIDENTIAL Control Script for IF Subsystem 14 GMRT

November 2008 TCS CONFIDENTIAL SACE-generated UI and Data Stream Visualization 15 GMRT

For more information, contact: Harrick Vin