Intelligent Robotics Group: Space and Planetary

Entrainment as a means of generating a robotic circadian rhythm

Claire Rocks

The Aurora Project aims to create and implement a European long-term plan for the exploration of the Solar System, culminating in a human expedition to Mars by 2030, recognised steps along the way include the robotic exploration of Mars and a robotic outpost. Necessary to autonomous robotic missions is activity coordination with the day-night cycle as robots intended for space missions often undergo many activities scheduled by a complex time series determined by their local day-night cycle. My research project looks at using the phenomenon of entrainment as a means of generating a robotic circadian rhythm that will adapt as the day changes due to changing seasons or changing global position. This work is aimed at increasing robot autonomy without the need for explicit programming. Entrainment is "the adjustment of rhythms of oscillating objects due to their weak interaction". Systems where we see the entrainment of living things are abundant in nature from thousands of fireflies that flash in unison to pacemaker cells in the heart, and almost all species exhibit daily changes in their behaviour or physiology synchronised with the day/night cycle. What controls these changes is a circadian clock that has the ability to be entrained by external stimuli; the most important of these stimuli is the day-night cycle caused by the rotation of the Earth. The ability to entrain enables organisms to coordinate their activities to the day-night and to re-synchronise with changing seasons; it also enables them to adjust to new time zones. This ability would be useful to a planetary robot, it could synchronise its activity schedule on landing and remain synchronised with the local environment as it moved around the planet.