Cheap, high-quality specialized sensors can be difficult to create for a number of reasons, because of a reliance on expensive materials, complicated functionality, or inherent reliability issues. Researchers at University of Washington have been working on developing mechanical movement sensors that are so cheap that they can be thrown away after every use.
The main structural material of the team’s sensors is paper towels that are infused with carbon nanotubes. By spraying a water-based solution containing carbon tubes onto the paper, the researchers had a cheap way of creating the material. Carbon nanotubes are conductive and a mesh of them creates a path for electricity to flow from one side of the sensor to another.
When the paper-based device is flexed, stretched, or torn, the electrical conductivity properties of the sensor change. This can be detected using traditional signal processing methods and the researchers have already used the new sensors to track finger movements and forces applied, detect a person’s heartbeats, and even monitoring the movements of an eye.
While the technology sounds cheap because paper towels were used, carbon nanotubes are certainly more expensive. Perhaps we’ll see a dramatic cost reduction in their production in the not too distant future.
Study in journal Advanced Materials Technologies: Fracture-Induced Mechanoelectrical Sensitivities of Paper-Based Nanocomposites…