CA Service

Control System Design

The development environment for safety critical control systems has become progressively more challenging for the control systems designer. Design processes and work products are specified in international standards and customers such as aviation, rail and road transportation authorities have become more literate in design best practices. Consequently the 21st century customer not only expects to receive a demonstrably safe and reliable control system but also requires systems assurance: visibility of the design process to give confidence that the constructor will produce an acceptable result. The 21st century designer therefore needs knowledge of international standards for best practice together with experience in applying semiformal methods to the design of complex discrete-event control systems. CA people have substantial depth in this area. We help our clients answer the questions:

  • What design processes and work products are required to comply with international standards for safety critical systems (for example, IEC 61508 and EN 50128)?
  • What cost and schedule impact does safety critical standards compliance have on a project?
  • How is finite state automata best applied to control system design?
  • What are the best options for format and content of design descriptions?
  • What is a "good" design?


CA provides either complete turnkey design solutions or works with control system design teams to improve outcomes. We have depth of experience in projects with IEC 61508 and EN 50128 compliance requirements. In these roles we:

  • Develop control strategies
  • Apply design patterns and frameworks
  • Prepare system architecture specifications
  • Prepare detailed design descriptions
  • Manage design teams
  • Mentor design engineers
  • Conduct design reviews.

Case Studies

Honeywell Taiwan CA designed the safety critical ventilation and air conditioning, building management and smoke extraction control systems for underground railway stations on the Taiwan high-speed rail network. Our design process complied with the requirements of EN 50128 Railway applications - Communications, signalling and processing systems - Software for railway control and protection systems for safety integrity level 2 (SIL 2).
Chemical Processing Process Control CA engineers have significant depth of experience in the control of complex chemical reactor systems.