Researchers are working on a new type of fabric that can ‘hear’.

The sound-sensitive threads could one day aid in a range of health and security challenges, according to scientists at MIT in the USA. 

The design uses an electrical fibre called a piezoelectric fibre woven into fabric yarns. 

Using a similar mechanism to the human ear, the researchers say it can convert pressure waves at audible frequencies into mechanical vibrations, which can then be processed into electrical signals. 

The machine-washable fabric could be used to detect the direction of a clapping sound, facilitate two-way communication and monitor the heart. 

Only a small quantity of the specialised piezoelectric fibre is required to render the fabric acoustically sensitive: just one fibre can be used to generate tens of square metres of fabric microphone, which is then capable of detecting weak sound signals such as human speech. 

The fabric can also be machine-washed, with draping qualities, making it ideal for wearable applications.

Three main applications have been demonstrated for the design when woven into shirts. 

The garment can detect the direction from which a clapping sound originates; facilitate two-way communication between two individuals, each of whom is wearing the acoustic fabric; and monitor the heart when the fabric is touching the skin. 

The authors anticipate that the new design could be applied to a variety of situations, including for security (for example, detecting where a gunshot has come from), aiding directional listening in individuals with hearing aids, or in real-time long-term monitoring for those with heart and respiratory conditions.

More details are accessible here.