Belgian NGO is training rats to carry backpacks. Here’s why

Rats, however, are being prepared to step in as an unlikely hero.

Rodents are outfitted with tiny, cutting-edge backpacks as part of the project, which was developed by Belgian non-profit APOPO, to assist first responders in their hunt for survivors among the ruins in disaster zones.

“Rats are typically quite curious and like to explore – and that is key for search and rescue,” says Donna Kean, a behavioral research scientist and leader of the project.

Rats are ideal at finding stuff in confined spaces because of their small size, keen sense of smell, and adventurous nature, according to Kean.

The rats are currently being taught to look for survivors in a disaster-relief simulation. They must first find the target individual in a room that is unoccupied, press a switch on their vest to activate a beeper, and then make their way back to base to receive a treat.

While the rodents are still in the early stages of training, APOPO is collaborating with the Eindhoven University of Technology to develop a backpack, which is equipped with a video camera, two-way microphone, and location transmitter to help first responders communicate with survivors.

“Together with the backpack and the training, the rats are incredibly useful for search and rescue,” says Kean.

The rat pack

At its base in Tanzania, APOPO has been training dogs and rats for more than ten years in the scent detection of tuberculosis and landmines. Its programmes employ African Giant Pouched Rats, which can live in captivity for up to eight years as opposed to the typical brown rat’s four years.

APOPO had been trying to start the search and rescue project for years but lacked financing and a search and rescue partner to assist it. The initiative was only formally launched in April 2021 when Kean joined the team. However, the team started investigating the notion after the volunteer search and rescue group GEA approached APOPO in 2017 about the possibilities of using rats in its missions.

The technology that allowed first responders to speak with victims via the rats was a crucial part of the search and rescue operation. Before electrical engineer Sander Verdiesen got involved, APOPO lacked this.

Verdiesen, who is pursuing a master’s degree in technology at Eindhoven University of Technology, interned with APOPO in 2019. He was given the responsibility of developing the initial version of the rat backpack, which will aid rescuers in understanding what is happening inside disaster zones.

The prototype was a 3D-printed plastic container with a video camera that sent live video to a receiver module on a laptop while also recording a high-definition copy on an SD card. Using a vest made of neoprene, the same material as scuba suits, it adhered to the rats.

Verdiesen flew to Tanzania to test out the equipment and says that initially, the rats “didn’t really know how to deal with it” but adapted quickly. “By the end, they were just running around with the backpack on, no problem at all,” he adds.

The challenge of building tiny tech

Verdiesen continued to improve the design even after his internship ended since the backpacks performed “better than predicted.”

It hasn’t been simple, though, to scale down technology and modify it for disaster areas.

According to Verdeisen, GPS can’t get through the thick building wreckage and rubble. The Inertial Measurement Unit, a position tracker embedded in the heels of firefighters’ boots, offers an option.

“If you’re walking, your foot is going to be still every step or so – that’s where you can re-calibrate. With the rats, we’re yet to find that,” he says. Other engineers are working on similar projects, so he’s hopeful they can find a solution.

Verdeisen is also attempting to reduce the size of the next edition while adding more technology, such a two-way microphone. The prototype was twice as heavy as expected, weighing in at about 140 grammes (4.9 ounces), but Verdeisen claims that bulkiness was more of a problem, measuring 10 centimetres long (3.9 inches) and 4 centimetres thick (1.6 inches).

“The rats were walking up against something that they would normally be able to go under, and suddenly they can’t anymore,” he explains.

Verdeisen intends to merge everything onto a single printed circuit board, which will free up more space, in order to make it “as tiny as possible” without sacrificing any functionality. He thinks that this improved model of the backpack may one day enable first responders to “find somebody that would otherwise not be rescued.” It should be available later this year.

Rodents to the rescue

Meanwhile, in Tanzania, Kean is increasing the complexity of the rats’ training environment, “to make it more like what they might encounter in real life.” That includes adding industrial sounds like drilling to mimic real emergencies.

The preliminary findings are encouraging; according to Kean’s observations, the rats are reacting well to the simulations that are getting harder. “They have to be highly confident in any environment, under any situations, and that’s something that these rats are naturally strong at,” she adds.

As part of a “habituation process,” handled rats are exposed to a range of locations, sights, noises, and people from birth. This makes incremental exposure to more extreme situations less distressing, claims Kean.

Animal care is a priority for APOPO because animals are at the heart of its operations and missions. The animals are trained in 15-minute sessions five days a week, and they spend their days in home cages alone or with siblings of the same sex once they stop working.

Eating a diet of fresh fruit and vegetables, they also get daily playtime in a custom-built playroom – although, for the search and rescue rats, training is very similar, “just with a little bit of direction,” says Kean.

The program is still in development, but Kean estimates it will take at least nine to 12 months to train each rat.

The team will develop “levels that imitate many stories of a collapsed structure” during the following round of training, according to Kean, and get closer to “real world circumstances.” The experiment will travel to Turkey, where GEA is situated, for additional training in more realistic surroundings once the rats are comfortable in more complicated environments. The rats might then interact with people in real-world scenarios if that works well.

However, for the time being, Kean and the Tanzanian team are concentrated on getting the rats through the initial round of training and, hopefully, into the field one day.

“Even if our rats find just one survivor at a debris site, I think we would be happy to know it’s made a difference somewhere,” Kean added.