Simple, not simplistic the middleware of behaviour models

There are many areas where software components must interact witch each other and where middleware provides the appropriate benefits of robustness, decoupling, and modularisation. However, there is a potential performance overhead that, for autonomous robotic and embedded systems, may be critical. Proposals for robotic middleware continue to emerge, but surprisingly, they repeatedly follow the publish-subscriber model. There are several disadvantages to the push paradigm of the publisher-subscriber approach; in particular, its implication of a closer coupling where the subscriber must be active and able to keep up with the pace of events. We propose an alternative pull model, where consumers of messages handle information at their own time. We show that our proposal aligns with fundamental, time-triggered design principles, and produces simple module communication that reduces thread management and can enable rapid prototyping, validation, and formal verification.