Timed Automata have proven to be useful for specification and verification of real-time systems. System design using Timed Automata relies on explicit manipulation of clock variables. A number of automated analyzers for Timed Automata have been developed. However, Timed Automata lack of composable patterns for high-level system design. Logic-based specification languages like Timed CSP and TCOZ are well suited for presenting compositional models of complex real-time systems. In this work, we define a set of composable Timed Automata patterns based on hierarchical constructs in timed enriched process algebras. The patterns facilitate hierarchical design of complex systems using Timed Automata. They also allow a systematic translation from Timed CSP/TCOZ models to Timed Automata so that analyzers for Timed Automata can be used to reason about TCOZ models. A prototype has been developed to support system design using Timed Automata patterns or, if given a TCOZ specification, to automate the translation from TCOZ to Timed Automata.

HighSpec is an interactive system for composing and checking OZTA specifications. The integrated high level specification language, OZTA, is a combination of Object-Z (OZ) and Timed Automata (TA). Building on the strength of Object-Z's in specifying data structures and Timed Automata's in modelling dynamic and real-time behaviors, OZTA is well suited for presenting complete and coherent requirement models for complex real-time systems. HighSpec supports editing, type-checking as well as projecting OZTA models into TA models and Alloy Models so that TA model checkers-UPPAAL and the Alloy Analyzer can be utilized for verification. Most importantly, HighSpec supports a novel yet effective mechanism advocated by OZTA for structural TA design, i.e., using a set of composable timed patterns to capture high level timing requirements and process behaviors and generate the TA part of model in a top-down way. HighSpec can also generate LaTeX document as an alternative media for the spread and read of established OZTA models.

When designing a complex system, Object-Z is a powerful logic-based language for modeling the system state aspects, and timed automata is an excellent graph-based notation for capturing timed control behaviour of the system. This paper presents an effective combination of the two techniques with novel composition and communication mechanisms. The combined notation enhances Object-Z with realtime modeling capability and also extends timed automata with enhanced structure and state modeling features.

The design of embedded and hybrid systems requires powerful mechanisms for modeling data, state, concurrency and real-time behaviour. The {first} part of this paper illustrates a powerful design notation Timed Communicating Object Z (TCOZ) that has both channel based and sensor/actuator based interfaces. We believe that TCOZ is well suited for presenting more complete and coherent design models for complex embedded and hybrid systems. However, the challenge is how to analyze and check these models with tools support. One effective approach is to project (transform) the design models into multiple domains, then to use existing specialized tools in those domains to perform the checking and analyzing tasks. The second part of this paper demonstrates one particular projection from TCOZ designs to Timed Automata (TA) models so that TA model checkers can be used to check time related properties.