A framework for building mobile robot applications . Application to multi - robot projects

The complexity of robot software systems calls for the use of some well-conceived architecture together with programming tools that support the architecture. These sets of tools are usually named robot programming frameworks. One common feature of robot architectures is the modular decomposition of systems into simpler and largely independent components. These components implement primitive actions and report events about their state. These modules are usually connected with different inter-process communication mechanisms. There are two basic communication approaches: client/server and publish/subscribe. The robot programming framework proposed here includes a tool (RoboGraph) to program and coordinate the activity (tasks) of these middleware modules. This tool is easily extensible to any architecture that uses a publish/subscribe communication approach. Project developers use the same task programming IDE (RoboGraph) in two different levels. The first one is to program tasks that must be executed by one robot and the second level is to program tasks that can include several robots and building elements. Tasks are described using an interpreted Petri net editor and stored in an xml file. A dispatcher loads these files and executes the different Petri nets as needed. A monitor that shows the state of all the running nets is very useful for debugging and tracing purposes. The whole system has been used in two different applications: A multi-robot surveillance project (WatchBot) and a tour-guide robot (GuideBot) that has been leading users in a public event (XuventudeGalicia.net) for the 2007 and 2008 editions.