The branch of study known as interactive robotics has soon moved beyond just performing pre-programmed, repetitive tasks to more complex activities such as interacting with living things. For example, biocompatible and biomimetic robots are increasingly used to study animals and plants.
Robotic systems that use animals in the loop are particularly useful for investigating collective behaviors that are difficult to study using traditional techniques. These systems not only offer new perspectives on animal behavior and conservation studies. They also promote engineering innovation in robots.
A recent partnership between the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland and the University of Graz in Austria has demonstrated how successful animal systems in the loop can be when a robotic system is designed and integrated into a honeybee colony.
Using a robotic device, the researchers conducted non-intrusive studies on three European honey bee (Apis mellifera) colonies in winters of 2020 and 2021. By adjusting temperatures, the researchers were able to influence bee movement within the hive, observe new patterns of movement, and analyze collective thermoregulation behaviors in the colony. The group published their findings in the journal Science Robotics in March.
Rafael Barmak, a PhD student at EPFL and one of the study's authors, describes the device as "basically a strange robotic system that is not only biocompatible but also has a set of sensors, electronic [and] thermal actuators to interact with honeybee colonies." Honey bees are very possessive and either eliminate or hide strangers who enter their hive. Therefore, in addition to the required robotic features, the engineers also had to consider the social behavior of honey bees when setting up their systems.
According to Barmak, using robots to survey animals automates tedious and repetitive tasks such as detecting local temperatures, which are crucial to a healthy hive and bee lifecycle.
“It is not easy to make temperature measurements within a honeybee colony. The unique feature of this device is that it surrounds the sensors contained by the bees after they have been successfully integrated into the colony. Otherwise, beekeepers and scientists often have to rely on inaccurate outside temperature data.
The EPFL-University of Graz team had to make several revisions before the design was perfect. At the top of the completed robot is an electrical panel that looks like a beekeeping frame. According to Barmak, the printed circuit board (PCB), which houses the thermal actuators, sensors and other supporting electronics, is right in the middle.
We have a processor called a microcontroller that manages all [work].” The first design, which had a PCB coated with only resin and coated with wax, was rejected by the bees. After that, the researchers chose to add a frame for a building template, and after trying several different materials, they settled on a 1-millimeter-thick laser-cut mesh to appeal to the colony.
Even the impending heat collapse of a colony can be detected by the device's sensor arrays. This happens when the temperature drops dangerously (below 10 ºC for the European honeybee, where the bees cannot flap their wings to generate heat). "We knew when we looked at the thermal data, after realizing that the bees were in danger, that they had stopped moving," says Barmak. The bees were spared when the researchers chose to turn up the heat using thermal actuators previously used to analyze the colony's collective actions.
Barmak and his team also used thermal stimuli, never before tried in winter colonies, to move bees around the colony. They discovered previously unrecognized behavioral patterns in bees and how closely they follow thermal cues, both of which can be used to create new beekeeping techniques. They are currently preparing to study the summer colonies with their robotic equipment, which will be a little more difficult because the bees are much more active then.
According to Barmak, the most important aspect of this robotic system is that it enables researchers to learn more about these creatures and improve current understanding. Besides sparking scientific curiosity, he claims it demonstrates the potential of using interactive robotic systems to study colonies of animals and then using the data to produce new e-farming tools, sensors and other things for the field.
📩 12/04/2023 16:27