In previous work we presented functional reactive programming (FRP), a general framework for designing hybrid systems and developing domain-specific languages for related domains. FRP's synchronous dataflow features, like event driven switching, supported by higher-order lazy functional abstractions of Haskell allows rapid development of modular and reusable specifications. In this paper, we look at more closely to the relation of arrowized FRP (AFRP), the FRP implementation, and formal specification of hybrid systems. We show how a formally specified hybrid system can be expressed in FRP and present a constructive proof showing that, for a subset of AFRP programs, there is a corresponding formal hybrid system specification.

Software for (semi-) autonomous robots tends to be a complex combination of components from many different application domains such as control theory, vision, and artificial intelligence. Components are often developed using their own domain-specific tools and abstractions. System integration can thus be a significant challenge, in particular when the application calls for a dynamic, adaptable system structure in which rigid boundaries between the subsystems are a performance impediment. We believe that, by identifying suitably abstract notions common to the different domains in question, it is possible to create a broader framework for software integration and to recast existing domain-specific frameworks in these terms. This approach simplifies integration and leads to improved reliability. In this paper, we show how Functional Reactive Programming (FRP) can serve as such a unifying framework for programming vision-guided, semi-autonomous robots and illustrate the benefits this approach entails. The key abstractions in FRP, reactive components describing continuous or discrete behavior in a declarative style, are first class entities, allowing the resulting systems to exhibit a dynamic, adaptable structure which we regard as especially important in the area of autonomous robots.