A diagram of this architecture
Icarus' modularity allows it to plan, execute and sense in parallel. Knowledge is uniformly accessed from Labyrinth. Labyrinth uses a uniform representation for its knowledge: a concept hierarchy, which gives it some efficiency for knowledge access.
Icarus as described in the references and in this document was never completed. In particular, although the Labyrinth, Daedalus, and Maeander components were built, the Argus module was only partially implemented. A reduced version of the Icarus architecture was built although it did not have the total functionality described in this document.
A diagram of this architecture