Collaborative control of robot motion: Robustness to error

We consider "collaborative control" systems, where multiple sources share control of a single robot. These sources could come from multiple sensors (sensor fusion), multiple control processes (subsumption), or multiple human operators. Reports suggest that such systems are highly fault tolerant, even with large numbers of sources. In this paper we develop a formal model, modeling sources with finite automata. A collaborative ensemble of sources generates a single stream of incremental steps to control the motion of a point robot moving in the plane. We first analyze system performance with a uniform ensemble of well-behaved deterministic sources. We then model malfunctioning sources that go silent or generate inverted control signals. We discover that performance initially improves in the presence of malfunctioning sources and remains robust even when a sizeable fraction of sources malfunction. Initial tests suggest similar results with non-deterministic (random) sources. The formal model may also provide insight into how humans can share control of an online robot.