In his early In the twenties, Lee Nam-hyun was a passionate swimmer. But in 2004, he broke his neck in the pool, leaving him paralyzed from the shoulder down. Recovery from injury takes years of rehabilitation.
The accident also temporarily halted his lifelong passion for singing. Opera and K-pop songs are his favorites, and the ability to re-sing has become one of his best recovery goals. But the lack of basic muscles and the limited capacity of the lungs meant that he could not even cough. When he tried to sing, he says, it sounded like whining or a little more than a whisper.
“The singing I sang before and after was completely different,” he says. “Tones, sounds, rhythms – I couldn’t take it anymore after I got hurt. It was a sound that could not be heard. ”
About two years after the accident, a health worker made him cough by pressing on his diaphragm. He learned that the pressure on his stomach could help him produce a bigger sound.
Nearly a decade later, he learned through a therapist about a prototype device made just for that purpose, and Lee began working with a biorobotics lab at Seoul National University. The device would eventually be named Exo-Abs. Its creators call it the first robotic device of its kind that helps people breathe, cough, speak and sing by automatically pressing on their stomachs.
The creators of the device, which started as a class project, hope to one day turn it into a commercial product. Researchers in the robotics lab first began working on a prototype device after popular singer Kim Hyuk-gun was hit by a car and paralyzed in 2012. Kim was the lead vocalist of Cross, a band whose songs remain a popular choice in South Korean karaoke bars. He is known for a singing style that may sound more like shouting, and two years after the injury he started working with a biorobotics lab on a device that allows him to sing with similar intensity. Only later did researchers learn that patients with spinal cord injuries often need help not only with limb relocation, but also with respiratory therapy.
“When you exhale, you’re basically pushing your stomach and narrowing your lung volume, so we try to mimic that process,” says Professor Cho Kyu-jin of Seoul National University.
Cho is the director of the Soft Robotics research center at the university, a biorobotics laboratory that draws inspiration from the natural world, including the human body. In addition to the Exo-Abs, Cho also created a robotic arm called the Exo-Glove, a glider with wings like a ladybug and a robot that simulates water skimmers, the so-called Jesus bugs because of their ability to walk on water.
“All wearable robots today are used to move limbs, such as arms, shoulders and legs,” he says. Exo-Abs is different because it “basically changes the entire volume of your body.” But he says the potential of the device is largely unexplored because it is not well known.
People who suffer from stroke or neurological disorders often need constant care, including respiratory therapy. Failure to clear the airways can lead to diseases such as pneumonia and premature death. Today, people use equipment like a ventilation mask to help them breathe, but the makers of Exo-Abs think their device could one day replace fans for some people.
Unlike existing devices that may require the use of a face mask or fan, the Exo-Abs can be hidden under a shirt. The machine controls are housed in a backpack that can be attached to the back of a wheelchair. The current iteration of the Exo-Abs includes strips placed over the chest and middle section to measure breathing and diaphragm pressure.
This is the third version of Exo-Abs. The first user operated the joystick manually and had to be plugged into an outlet. Another version is with backpacks for people with illnesses like COPD who may not need help all the time, but may have trouble, for example, climbing stairs without breathing.
The latest version of Exo-Abs uses artificial intelligence to regulate the pressure applied to the middle part of the person. The AI is powered by sensors that include a microphone that detects when a person is speaking and an elastic tube pulled by a belt around the middle to monitor breathing levels. It also affects a person’s physical fitness, body shape, user’s abdominal stiffness, and user activity. Singing that requires a lot of effort like opera, for example, may require more pressure than sitting quietly and talking.
Lee Sang-yoep, a PhD student at Seoul National University who works with Choo, envisions other uses of Exo-Abs, such as synchronizing artificial abs with music or singing puzzles like Applause with one hand.