The wearable device uses skin-stimulation technology to provide feedback, helping with navigation, balance, and assisting those with visual impairments or prosthetics.
A team of engineers led by Northwestern University has created a new wearable device that stimulates the skin to deliver a range of complex sensations.
This thin, flexible device adheres comfortably to the skin, offering realistic and immersive sensory experiences. While it holds promise for gaming and virtual reality (VR), the researchers also see potential in healthcare. For instance, it could help people with visual impairments “feel” their environment or provide feedback for users with prosthetic limbs.
Leveraging skin-stored energy
The device consists of a hexagonal array of 19 miniature magnetic actuators embedded within a thin, flexible silicone-mesh material. Each actuator can deliver distinct sensations, such as pressure, vibration, and twisting. Using Bluetooth technology in a smartphone, the device receives information about a person’s surroundings, translating it into tactile feedback—substituting one sensation (like vision) for another (touch).
To conserve energy, the device uses a “bistable” design, allowing it to hold two stable positions without continuous energy input. When the actuators press down, energy is stored in both the skin and the device’s internal structure. As they push back up, only a small amount of energy is used to release this stored energy. This efficient design enables the device to operate longer on a single battery charge.
Sensory substitution
To test the device, the researchers blindfolded healthy subjects and evaluated their ability to avoid obstacles, adjust foot placement to prevent injury, and modify their posture to improve balance.
In one experiment, subjects navigated a path filled with obstacles. As they approached an object, the device provided feedback through increasing light intensity in the upper right corner. The feedback intensified and moved closer to the center as the subject got closer to the obstacle. After a brief training period, the subjects were able to adjust their behavior in real-time based on the feedback.
Reference: John Rogers, Bioelastic state recovery for haptic sensory substitution, Nature (2024). DOI: 10.1038/s41586-024-08155-9. www.nature.com/articles/s41586-024-08155-9
