Could 'cyborg' cockroaches be the unlikely heroes on rescue missions?

A giant cockroach scuttling towards you might send a shiver down your spine. But these creepy-crawlies could one day become unlikely heroes on rescue missions.

Scientists at the University of Queensland and the University of New South Wales in Australia have developed 'cyborg' cockroaches for search-and-rescue missions. They call them "paraborgs", short for paramedic cyborgs.

The researchers used North Queensland giant burrowing cockroaches. These can grow up to 8.5 centimetres long and are the world's heaviest cockroach species.

Each insect was fitted with a tiny backpack containing a camera or a syringe-like device for delivering medicine.

Small electrodes, which carry electrical signals, were implanted into the cockroach. Operators could then send small signals to its nervous system, allowing them to steer it remotely using a gaming controller.

When close enough a needle carrying medicine can be shot into a patient.

Biorobotics engineer Thang Vo-Doan, who helped write the study, said: "We start with anaesthetising (putting to sleep temporarily) the insect, immobilising them so that we make sure that they cannot feel anything during the implementation process."

Cockroaches were chosen because they can squeeze through tight gaps, move across difficult surfaces and survive in tough conditions. They also need much less power than actual robots.

The injection system has not been tested on people, yet. Experiments used silicone targets or pig skin in controlled laboratory conditions.

During the lab tests, one "observer" cockroach used a camera to find a target. A second carried the injection equipment and released a dose of medicine when remotely instructed.

The cockroaches reached all their checkpoints. Overall, 72% of attempted medicine deliveries succeeded.

When an insect launched the injection from within 15 centimetres of its target, the success rate reached as high as 95%.

Researchers believe the insects might eventually reach people trapped under collapsed buildings or inside caves. They could potentially deliver emergency medicine for severe allergic reactions or snake bites while human rescuers are still trying to reach someone who is hurt.

Researchers must now investigate problems including blocked signals, dangerous terrain and making sure injections can be delivered safely.

The scientists eventually hope to send swarms of paraborgs into disaster areas, with some searching for survivors and others carrying medicine.