The deaf cannot hear. As such, it is difficult for them to obtain information from sounds in the environment, warnings, and animal cries. Given the desire to convey sound using design and technology, the developers worked with the deaf on their university graduation project and began developing Ontenna.
When the device was first attached directly to the skin, users complained about maceration and numbness. When attached to clothing, users commented on the difficulty of feeling the vibration. When attached to fingers and arms, the device interfered with signing and housework. Eventually, the developers came up with the idea of attaching the device to the hair, which allows for easier vibration recognition because the approach applies tension without direct skin contact.
Ontenna conveys sound characteristics by converting sound pressure in the 30 - 90 dB range into 256 gradations of vibration and light. Using Ontenna, deaf persons are thus able to sense animal cries, the approach of cars, the rhythm of drums, and the sound of chimes. The light also conveys sound information to those nearby. Seeing deaf persons who rarely use their voices begin to communicate vocally was moving.