This "Smart Pillow" Uses Nanogenerators to Track Head Movement, and Health, While You Sleep
Based on a flexible, breathable triboelectric nanogenerator design, this self-powered sensor matrix tracks your head movements.
A team from the Chinese Academy of Sciences has developed a pillow with a difference: It holds an array of triboelectric generators designed to keep an eye on you while you sleep, firing off an alert if you're at risk of falling out of bed.
"Here, a pressure-sensitive, non-invasive, and comfortable smart pillow is developed based on a flexible and breathable triboelectric nanogenerator (FB-TENG) sensor array, which can monitor head movement in real time during sleep," the researchers explain of their work. "The FB-TENG is based on flexible and breathable porous poly(dimethylsiloxane) (PDMS) with a fluorinated ethylene propylene (FEP) powder and exhibits pressure sensitivity and durability."
Targeting low-cost monitoring of sleep behaviors, the smart pillow uses a technology normally found in wearable energy harvesting systems — but rather than powering anything directly, the user's movements generate the energy required to form a grid of pressure sensors with touch and motion tracking.
"The smart pillow is formed by laying the self-powered pressure sensor array on an ordinary pillow to realize real-time monitoring of the head position in a static state and head movement trajectory in a dynamic state during sleep," the team explains. "Additionally, the smart pillow also has an early warning function for falling out of bed."
The material from which the sensor matrix is made is breathable, soft, yet strong — in one demonstration the researchers dangle a 1kg (around 2.2lbs) weight from its edge without trouble. As the user's head moves, press and release signals are generated — and can be visually mapped via a connected computer.
The team is hopeful that the technology could improve sleep tracking, but have their sites set beyond: Medical uses have been proposed including the observation of patients with brain conditions and neck disorders including cervical spondylosis, where the pillow could offer long-term in-home monitoring.
The team's work has been published in the journal Applied Materials & Interfaces under closed-access terms.