Humans have always been fascinated by scales different from their own, from giant objects such as stars, planets and galaxies, to the tiny world: insects, bacteria, viruses and other microscopic objects. If the microscope allows us to see and observe the microscopic world, it is still difficult to interact directly with it.
However, human-robot interaction technology could change all that. Microrobots, for example, can interact with the environment on much smaller scales than we do. Microsensors have been used to measure the forces exerted by insects during activities such as flying or walking. However, most studies so far have focused only on measuring insect behavior rather than a direct insect-microsensor interaction.
In this context, researchers from Ritsumeikan University in Japan have now developed a flexible micro-robotic finger that can allow more direct interaction with the microworld. The study, led by Professor Satoshi Konishi, was published in Scientific Reports on October 10, 2022 “A tactile microfinger is obtained by using a flexible liquid metal strain sensor. A soft pneumatic balloon actuator acts like an artificial muscle, allowing sensor control and movement. With a robotic glove, a human user can directly control the micro fingers. This type of system allows safe interaction with insects and other microscopic objects,” says Professor Konishi.
Using their newly developed microrobot setup, the research team studied the reaction force of a woodlouse as a representative sample of an insect. The woodlouse was fixed in place using a suction tool and the microfinger was used to apply force and measure the reaction force of the woodlouse’s legs.
The reaction force measured from the woodlouse’s legs was about 10 mN (millinewtons), which was in line with previously estimated values. Although it is a representative study and a proof of concept, this result is very promising for the realization of direct human interactions with the microworld. Moreover, it may have applications even in augmented reality (AR) technology. Using robotic gloves and micro-sensing tools such as the microfinger, many AR technologies regarding human-environment interactions at the microscopic scale can be realized.
“Using our strain-sensitive micro-finger, we were able to directly measure the pushing motion and force of a woodlouse’s legs and torso – something that was impossible to achieve before! We anticipate that our results will lead to further technological developments. for micro-finger-insect interactions, leading to human-environment interactions at much smaller scales,” remarks Professor Konishi.