These Arduino-compatible sensors will turn your skin into a touch-sensitive interface for your mobile devices.
Sifting through a pocketbook for a ringing smartphone during a meeting can be quite embarrassing. Not to mention, trying to precisely tap out a message on your wrist can draw some attention. While modern-day wearables have given users the ability to glance at their calendar, receive texts and pretty much anything else Dick Tracy could’ve envisioned, the usable interfaces offered by these devices tend to be a bit small, thus making it difficult to accurately select buttons or type an email.
That may soon be a thing of the past if a new experimental project, which is currently being developed by a team of computer scientists from Saarland University and researchers from Carnegie Mellon University, is able to catch on. Inspired by recent advancements in electronic skin technology, iSkin is a thin, flexible and soft silicone overlay that is worn directly on the skin allowing the human body to act as an input surface for mobile human-computer interaction.
“The human skin is recognized as a promising input surface for interactions with mobile and wearable devices. However, it has been difficult to design and implement touch sensors that can be placed directly on the skin,” the team writes.
The stickers enable a wearer to receive and deliver commands on-the-sly, thereby controlling companion mobile devices just as any other wrist-adorned gadget would. Better yet, should one of them only be needed intermittently, the sensors can be removed, rolled up and easily stowed when not in use. Because of the flexible material used, iSkin can be manufactured in a variety of shapes, sizes and personalized designs.
Potential use cases for the stickers include incoming and outgoing calls, controlling music, typing and sending messages, or just anything else typically done on a mobile device. They’re capable of multi-touch functionality and even recognize gestures.
To receive and transmit tactile input, the iSkin houses electrodes sandwiched between the silicone layers. Projected capacitive sensing uses capacitive coupling between the two electrodes, whereas resistive touch sensing relies upon pressure to create a contact through the permeable spacing layer. Bringing a finger close to an electrode reduces the mutual capacitance, while pressure (such as the pressing of one’s finger) creates contact between both electodes and closes the circuit. A black carbon powder connects the electrodes to one another, allowing them to be situated into any design. Meanwhile, the flexible patch is tethered by a ribbon cable to an Arduino-compatible microcontroller (Teensy dev board), which processes the data and drives the sensor.
“Integrating capacitive and resistive touch sensing, the sensor is capable of detecting touch input with two levels of pressure, even when stretched by 30% or when bent with a radius of 0.5 cm. Furthermore, iSkin supports single or multiple touch areas of custom shape and arrangement, as well as more complex widgets, such as sliders and click wheels,” the recently-published paper reveals.
At the moment, the prototypes are hard-wired to a computer. However, the team aspires to integrate chips that will let the stickers to wirelessly communicate with other output devices ranging from smartphones to health monitors. Intrigued? You can read the project’s paper in its entirety here. By the way, this remind us… what ever happened to the Circet Bracelet?