A Novel Control Architecture for Mobile Robots in Safety-Critical Applications

Mobile robots have become more and more common in public space. This increases the importance of meeting safety requirements of autonomous robots. Simple mechanisms, such as emergency breaking, alone do not suffice in these highly dynamic situations. A more sophisticated situational assessment and planning is needed as part of the high-level process control. This paper presents the concept of a safety-critical Robot Control Architecture for mobile robots based on a Hierarchical Finite State Machine. It expands already existing architectures by putting the focus on concurrency, interruptibility and code reusability to allow for straightforward implementation of safety mechanisms such as internal diagnostics systems. In doing so, this concept presents the template of a new type of state machine implementation. It is is demonstrated with the application of a delivery robot in the scope of a German research project.