Modelling a real time control system based on distributed objects

The CERN Research and Development project (RD-38), named CICERO, aims to identify and design the main building blocks of a generic control information system based on distributed objects. The project is producing an integrating framework (named Cortex) into which user real-time control objects will ultimately be plugged (and played) and a control information system to support its configuration and management. Development of Cortex is following the ESA PSS-05-02 software engineering standards. Cortex is providing an environment which allows real-time control systems to share information, control and analysis functions which presents a uniform human interface; which permits upgrades and additions without code modification; and which is sufficiently generic to allow its use both by existing or future control systems at CERN and by industrial real time control systems. It provides both high level data access, abstracting objects to a level appropriate for on-line control and low level data access to allow views of experimental sub-components for detailed real-time control. Additionally, the Cortex system shall enable developers to grow their control systems from a lab-based test system to the complete experimental system and is therefore both scaleable and flexible to change. Technical solutions are being identified in CICERO which could later be the major components of a basic turnkey control system for future medium to large scale HEP experiments and accelerators as well as for industrial control systems. This paper outlines the modelling concepts behind Cortex.