ERTL: An Extension to RTL for Requirements Analysis for Hybrid Systems (1997)

Author(s): R. de Lemos and J. G. Hall

Abstact: Real Time Logic, RTL, was introduced by Jahanian and mok in [5] as a formalism for reasoning about the absolute timing properties of real-time systems. The need for RTL came from a perceived inextensibility of research at that time form relative timing problems of systems to absolute timings. RTL is a first order logic with an uninterpreted predicate which relates events of a system to the time of their occurrence. RTL assumes, as its model of time, a total order isomorphic to the natural numbers. In this paper we provide extensions to RTL which allow reasoning about absolute timings for both continuous and discrete time, and reaoning about system behaviour in the value and time domains by parameterising predicates in terms of system variables. Incorporating these features into RTL we obtain Extended Real-Time Logic (ERTL) which is suitable for the modelling and analysis of hybrid systems