Stretchable Tactile Sensor Developed for Robotic, Caregiving Applications

Apr 11, 2014
Jyunichi Oshita, Nikkei Digital Health
A demonstration of the flexible tactile sensor
A demonstration of the flexible tactile sensor
[Click to enlarge image]

Nippon Mektron Ltd exhibited a "flexible tactile sensor" made by using a flexible printed circuit (FPC) board at a trade show in Tokyo.

The sensor is expected to be used for (1) robot hands having a tactile sense, (2) mattresses that detect pressure for nursing care services, (3) input interfaces for mobile devices, etc. The company is currently providing samples of the sensor to specific customers, planning to commercialize it within fiscal 2014. The sensor was showcased at Medtec Japan 2014, which runs from April 9 to 11, 2014.

The flexible tactile sensor is made by adding pressure sensing capability to an FPC board. It consists of two polyimide films between which a thin film called "pressure sensing film" and electrodes are sandwiched.

When a pressure is applied between the polyimide films and the pressure sensing film touches the electrodes, a resistance change occurs depending on the pressure. The flexible tactile sensor measures pressure by using this mechanism.

The sensor can measure a pressure of up to 2-3kg/cm2. Because the entire sensor is as thin as 200μm, it can be attached to a curved surface. Nippon Mektron did not disclose the materials used for the pressure sensing film.

This time, Nippon Mektron also exhibited a "stretchable FPC," an FPC board that can be freely stretched. Its base material is elastomer. The company made improvements to the pattern shape of its metal lines (copper foil) so that the lines also become stretchable.

The stretchable FPC can be attached to human body and is expected to be used in healthcare and medical applications. However, Nippon Mektron is still developing applications and has not yet decided when to commercialize it.