A research group at Waseda University and other institutions developed a "cyborg insect" that can operate even in narrow and harsh sites where humans cannot enter during disasters. When equipping it with a compact device generating oxygen for respiration, it was able to operate underwater for up to three hours. Through this, utilization in both underwater and terrestrial environments can be expected. In the future, they plan to continue experiments testing whether it operates stably in marshes or places with water currents, aiming to make it useful at disaster rescue sites.
A research group including Professor Shinjiro Umezu, who specializes in mechanical engineering, at the Graduate School of Creative Science and Engineering, Waseda University, jointly with Professor Hirotaka Sato at Nanyang Technological University in Singapore, has researched compact machinery utilizing abilities that insects possess. This time, using the Madagascar hissing cockroach, which lives in warm regions and does not inhabit Japan, they tackled the development of an amphibious cyborg insect.
Provided by Nanyang Technological University, Singapore
Although the Madagascar hissing cockroach has the name "cockroach", it differs greatly from the "unpopular" cockroaches. First, because its wings have degenerated, it does not fly, and when one attempts to catch it, it emits a "hissing" sound for intimidation. In size as well, it is about the size of the back of a human hand, and its body weight is large at approximately 5 grams. Normally living on land, it possesses characteristics of being easy to rear at low cost due to being omnivorous. When submerged underwater, it cannot take in oxygen and therefore ceases activity within a few minutes.
The research group turned the insect into a cyborg by mounting an oxygen generation tank, a diving suit covering it, and a total of four silicone oxygen-supply tubes (two each on the left and right) on the back of the cockroach. They investigated how long it could operate underwater. The resin oxygen-generating tanks were fabricated using a 3D printer. They designed a mechanism supplying oxygen through chemical reactions between manganese dioxide and hydrogen peroxide.
As a result, oxygen was supplied through spiracles, and it was able to continue activity underwater for up to three hours. In addition, they confirmed that both entry into water and exit onto land are possible through guidance via electrical stimulation. Umezu explains: "It is good to imagine diving. Just as a human carries an oxygen tank on the back when diving into the sea, the Madagascar hissing cockroach operated underwater using oxygen."
Provided by Nanyang Technological University, Singapore
It was announced that this cyborg insect can carry equipment weighing up to approximately 15 grams. The diving suit and control unit this time weigh approximately 6 grams in total, leaving a weight allowance that can add sensors or other equipment in the future. Therefore, if equipment such as cameras, sensors, AI (artificial intelligence), and sensing can be contained within a few grams, by forming a formation and moving several insects simultaneously, they state that obtaining positional information through coordinates or confirming during a disaster whether heat is emitted by a human trapped in a narrow place or generated from machinery becomes possible.
Provided by Nanyang Technological University, Singapore
Umezu stated: "We wish to continue verifications in environments close to disaster sites. Succeeding once or twice in harsh environments is sufficient for writing a paper, but insufficient at disaster sites. We wish to advance research on whether it can move stably even in places possessing obstacles such as slippery walls or rubble." Regarding prevention of egg-laying during activity at disaster sites, they intend to use males.
The research was conducted with grants from the Ministry of Education of Singapore and other organizations. The findings were published in the online edition of the British scientific journal Nature Communications on June 29, and Waseda University announced the achievement on the same day.
Original article was provided by the Science Portal and has been translated by Science Japan.