Composition and Compositionality in a Component Model for Autonomous Robots
Résumé
Component models for autonomous robots control architectures are much more constrained than traditional ones: obeying strict timing constraints, coping with a large spectrum of rapidly changing hardware (e.g. sensors and actuators), etc. Beyond introducing new concepts into components themselves, composition in such models must go much farther than the standard connection through method signature interfaces. Viewing components as full-fledged sensori-motor behaviors, our model follows the concept of rich interfaces introduced by Henzinger et al. to attach to each component all the necessary syntactical and behavioral information to make them externally composable. This paper presents two kinds of composition, parallel and by modes, their semantics, their compositionality properties and the impact of these on the composition model. A prototype implementation in Java is backed by a constructive semantics defined as a constraint system solved in this prototype with the ECLIPSe constraint programming system.