Public pools are closing worldwide due to a trained lifeguard labor shortage. The answer to this problem? Robots, of course.
As a press statement by Fraunhofer, a German technology firm, points out, "many swimming pools in Germany do not have enough trained lifeguards and in many places, this skilled labor shortage is even leading to closures."
The company's in-development attempt at a solution is a floating underwater rescue robot that works alongside rescue staff in emergency situations.
A research team from Fraunhofer Institute for Optronics, System Technologies, and Image Exploitation IOSB in Ilmenau developed the robot with the help of Halle’s water rescue service, Wasserrettungsdienstes Halle e.V.
According to the life-saving association, the Deutsche Lebens-Rettungsgesellschaft (DLRG), nearly 420 people drowned in Germany in 2019. While the majority of these drownings occurred in freshwater lakes, fatal accidents did also occur in public swimming pools.
The Fraunhofer press statement attributes this to a countrywide lack of trained pool lifeguards.
How the robot lifeguard works
The team's robot is an autonomous system that recognizes when a swimmer is in danger, leading it to take action.
"There are typical postures that you can use to recognize when someone is in danger," says computer scientist and project lead Helge Renkewitz.
Surveillance cameras mounted on the swimming pool's ceiling register the movement patterns of a swimmer who is in danger. This information is linked to the robot so that it can help the individual.
When the robot reaches the individual, it secures them and carries them to the water's surface. The robot uses a special mechanism for securing unconscious individuals so they don't slide off as they surface.
When not in use, the robot is safely stored away in a docking station on the swimming pool floor, which only opens in the case of an emergency.
The robot can even be deployed at swimming lakes where drones can take on the task of the surveillance cameras. In a lake, where underwater visibility is often restricted, the robot is equipped with acoustic sensors instead of optical ones.
Successful open-water tests
The researchers tested their technology at the Hufeisensee lake in Halle (Saale). For the open-water testing, an 80-kilogram (176 lb) dummy was deposited at a depth of three meters in the lake.
The robot was shown to be capable of securing the dummy, bringing it to the surface within a second, and carrying it above water to the shore — some 40 meters away.
"The full rescue operation lasted just over two minutes. Casualties must be resuscitated within five minutes to avoid long-term damage to the brain. We were able to stay within this critical time frame without any problems," says Renkewitz.
The robot is equipped with batteries, a motor, cameras, and optical and navigational sensors. The current model is 90 centimeters long (35 inches), 50 centimeters high (19 inches), and 50 centimeters wide.
The team says it aims to reduce the size of the rescue system and make it smaller, lighter, and more cost-effective than the current prototype. They say their streamlined design will resemble a manta ray, allowing it to easily glide through the water.
The robot could also be modified in the future for other tasks such as offshore and dam wall inspections, or for monitoring coral reefs or natural habitats.
"Our underwater vehicles have a very broad range of applications. For example, they are also suitable for detecting and verifying archaeological artifacts at the bottom of lakes," the researchers say.
The team's expertise adds to the growing field of underwater robotics, which promises to make our pools safer at the same time as opening up a whole host of applications for scientific research.