A Temperature-Modulating Robotic System

Swiss Federal Institute of Technology, Lausanne, Switzerland

The robotic system is shown in an experimental hive at the University of Graz. (Image: Artificial Life Lab/University of Graz/Hiveopolis)

A research team has developed a robotic system that can be unobtrusively built into the frame of a standard honeybee hive. Composed of an array of thermal sensors and actuators, the system measures and modulates honeybee behavior through localized temperature variations.

“Many rules of bee society — from collective and individual interactions to raising a healthy brood — are regulated by temperature, so we leveraged that for this study,” said EPFL Ph.D. student Rafael Barmak. The thermal sensors create a snapshot of the bees’ collective behavior, while the actuators allow us to influence their movement by modulating thermal fields.”

“Previous studies on the thermal behavior of honeybees in winter have relied on observing the bees or manipulating the outside temperature,” said the University of Graz’ Martin Stefanec. “Our robotic system enables us to change the temperature from within the cluster, emulating the heating behavior of core bees there, and allowing us to study how the winter cluster actively regulates its temperature.”

Thanks to the researchers’ biocompatible robotic system, the team was able to study three experimental hives, located at the Artificial Life Lab at the University of Graz, during winter and to control them remotely from EPFL. Inside the device, a central processor coordinated the sensors, sent commands to the actuators, and transmitted data to the scientists, demonstrating that the system could be used to study bees with no intrusion — or even cameras.

“By gathering data on the bees’ position and creating warmer areas in the hive, we were able to encourage them to move around in ways they would never normally do in nature during the winter, when they tend to huddle together to conserve energy,” said Mobile Robotic Systems Group head Francesco Mondada. “This gives us the possibility to act on behalf of a colony, for example by directing it toward a food source, or discouraging it from dividing into too-small groups, which can threaten its survival.”

The scientists were able to prolong the survival of a colony following the death of its queen by distributing heat energy via the actuators. The system's ability to mitigate colony collapse could have implications for bee survivability, which has become a growing concern. In addition to its potential to support colonies, the system has also shed light on honeybee behaviors that have never been observed, opening new avenues in biological research.

“The local thermal stimuli produced by our system revealed previously unreported dynamics that are generating exciting new questions and hypotheses,” said EPFL's Rob Mills. “For example, currently, no model can explain why we were able to encourage the bees to cross some cold temperature ‘valleys’ within the hive.”

The researchers now plan to study bees in the summer, which is a critical period for raising young. In parallel, the Mobile Robotic Systems Group is exploring systems using vibrational pathways to interact with honeybees.

“The biological acceptance aspect of this work is critical: the fact that the bees accepted the integration of electronics into the hive gives our device great potential for different scientific or agricultural applications,” said Mondada.

For more information, contact Celia Luterbacher at This email address is being protected from spambots. You need JavaScript enabled to view it.; +41-216-938-759.