Control law diagrams in Circus

Abstract

Control diagrams are routinely used by engineers in the design of control systems. Yet, currently the formal verification of programs that implement the diagrams is a challenge. We present a strategy to translate block diagrams to Circus, a notation that combines Z, CSP, and a refinement calculus. This work is based on existing tools that produce Z and CSP specifications from discrete-time block diagrams. By using a combined notation, we provide a specification that considers both functional and behavioural aspects of these diagrams, and can cover a wider range of blocks. Moreover, the Circus refinement calculus can be used to verify implementations, and reason about the block diagrams. © Springer-Verlag Berlin Heidelberg 2005.