Over the years many types of insects have received the cyborg treatment. Cyborg locusts could use their sensitive noses to sniff out explosives, cyborg dragonflies can make for zippy little drones, and cyborg cockroaches could scurry through disaster zones searching for survivors.

Previous versions have used small batteries to power the electronics, but that adds a time limit to their function before they need to be charged or swapped out. So for the new study, researchers at RIKEN integrated solar cells into cyborg cockroaches.

The team mounted electronics onto the backs of Madagascar cockroaches, which grow to about 6 cm (2.4 in) long. That electronics package includes a lithium polymer battery, a wireless receiver and a module that controls the insect’s legs, fitted into a 3D-printed “backpack” that matched the curve of its thorax.

They connected this to an organic solar cell module mounted on the cockroach’s abdomen. This ultra-thin film measures just 0.004 mm thick, to keep them light enough for the bugs to carry. Adhesive and non-adhesive sections were used in different parts of the film so as not to impede the cockroaches’ movement.

These solar cells had a power output of 17.2 mW, which is enough to run the electronics for two hours after 30 minutes of charging in the sun. The team says this output is 50 times higher than other energy-harvesting devices used on living insects.

These improvements could make cyborg cockroaches even better at scurrying through collapsed buildings looking for survivors, or remotely monitoring conditions with small sensors. The team says that the new design could also be adapted to other types of cyborg insects.

The research was published in the journal npj Flexible Electronics.

Source: RIKEN via Eurekalert