An international team led by researchers at the RIKEN Cluster for Pioneering Research (CPR) in Japan has discovered a technique to make remote-controlled cyborg cockroaches even more sophisticated by charging them with a tiny solar cell module.
Insects are remarkable; they:
- Can survive in hazardous situations,
- Can use a variety of powerful sensory organs,
- Are small enough to access inaccessible locations,
- Can quickly climb surfaces or fly.
These qualities benefit robots, or even better, cyborgs made by attaching electronic components to biological insects.
How is the Cockroach Turned Into a Cyborg?
The researchers attached electronics to the backs of Madagascar cockroaches. A 3D-printed “backpack” that matches the shape of the insect’s thorax holds the electronics, which includes a rechargeable lithium polymer battery, a wireless receiver, and a module that controls the insect’s legs.
They attached this to a module of organic solar cells fastened to the cockroach’s abdomen. The electronics are covered in an ultra-thin film that is only 4 micrometers thick (about 18 times thinner than one human hair) to send electrical impulses to control the cockroach. At the same time, it remains portable and does not impair the basic movements of the insects.
Researchers tested thicker solar cell films. However, the cockroaches took twice as long to run the same distance and had difficulty righting themselves when they flipped on their backs.
Finally, adhesive and non-adhesive parts were used at various points of the film to avoid impeding the cockroaches’ mobility,
“Considering the deformation of the thorax and abdomen during basic locomotion, a hybrid electronic system of rigid and flexible elements in the thorax and ultrasoft devices in the abdomen appears to be an effective design for cyborg cockroaches. Moreover, since abdominal deformation is not unique to cockroaches, our strategy can be adapted to other insects like beetles, or perhaps even flying insects like cicadas in the future.” said Kenjiro Fukuda from the Riken Cluster for Pioneering Research in Japan.
Excellent Power Output
After charging for 30 minutes in the light, these solar cells had a power output of 17.2 mW, sufficient to run the electronics for two hours. According to the research team, this device’s output is 50 times more than other state-of-the-art energy-harvesting devices employed on living insects.
Kenjiro Fukuda said:
“Body-mounted, energy-harvesting devices are critical for expanding the range of activity and functionality of cyborg insects.”
Madagascar Cockroaches
The Madagascar hissing cockroach is a black-and-brown invertebrate that can grow to 2.4 in (6 cm) long. The roaches are native to the island of Madagascar, off the coast of Africa. They make the hissing sound by quickly moving air through openings in their back when it feels threatened. The sound resembles a snake’s tail rattling.
Other Cyborg Insects
Many insect species have undergone cyborg transformation over the years, including:
- In 2012, North Carolina State University experimented with Madagascar hissing cockroaches with backpacks that trick the cockroach’s antennae to control its direction.
- In 2014, North Carolina State University fitted cockroaches with electrical backpacks with tiny microphones to detect and track faint sounds.
- In 2015 a team of scientists at Texas A&M University created a backpack to control discoid roaches. They were able to follow commands correctly 60% of the time.
- In 2017, engineers at The Charles Stark Draper Laboratory created cyborg dragonflies called DragonflEye, with backpacks that can control their flight to be used as nimble miniature drones.
- In 2017, North Carolina State University created cyborg cockroaches with sensors and technology, allowing them to map out an area. The researchers hope they could one day be used in disaster zones to look for survivors.
- In 2020, Cyborg locusts were created that could sniff out explosives with electrodes connected to their brains to transmit the information. They were only 60% accurate at detecting explosives, while a group of seven locusts had an accuracy of 80%.
The electronics in earlier models were powered by tiny batteries, limiting how long they could operate before needing to be recharged or replaced. With this in mind, RIKEN CPR researchers modified cockroaches to include solar cells in their latest study. With a solar cell, researchers could remote control a cockroach indefinitely since they would no longer be constrained by battery life. The solar cell also removes the need to recharge the battery with a docking station.
Conclusion
These advancements could make cockroach cyborgs even more efficient at search and rescue missions or using tiny sensors to monitor environmental conditions remotely. Moreover, the research team claims they could apply the new design to several other insect species. The research was published on September 5, 2022, in the journal npj Flexible Electronics.
Watch the cyborg cockroach charge its special backpack in the video below.
