Business Today

Buttons that pop out over touch displays

Virat Markandeya | Print Edition: Oct 26, 2014
Micah Yairi, CTO, Tactus Technology.
Micah Yairi, CTO, Tactus Technology. He was working on ways to deliver drugs through the skin using microfluidics.

Tactus Technology

Touch keyboards are almost impossible to navigate blind, but not our physical keyboards. The reason is the tactile feedback our fingers get from the raised qwerty keys. Tactus Technology, a California-based company, has been working on buttons that physically morph out and then flatten back from a thin panel that can be placed over touchscreens. The company traces back to research work on drug delivery systems through the skin, using microfluidics, a technology applied in inkjet printers and LCD screens.


California, 2007. Apple has launched the iPhone and Craig Ciesla has bought one. But he doesn't quite bask in the afterglow of the unboxed product. In an online video, Ciesla says that he still likes his BlackBerry for its physical, tactile buttons. Ciesla, a fibre optics specialist, who has been involved in product development, is also bandying business ideas with his friend and colleague, Micah Yairi, who was then working on drug delivery systems. Yairi may have told Ciesla about a journal article he published that year. It was about a pump that could control microfluidic channels to generate high pressure (eh? we'll unpack that next up). The paper abstract says it could find applications in systems ranging from drug delivery, to cooling microchips to filtration. Yairi may not have initially thought of it, but creating a morphable surface that sits over a touchscreen interface could perhaps be yet another.

How It Works

Let's back out a bit. Microfluidics is fluid physics at extremely small scales - below a millionth of a litre. Just as the integrated circuit put discrete components onto a chip, automation of fluid micro-channel networks could allow a biology or chemistry lab on a chip. This is like plumbing - with pumps and valves that allow an assembly line for fluid manipulation - at a miniaturised scale.

But fluid physics changes dramatically as the scale changes, unlike microelectronics where transistors have become smaller and smaller, to the point of single-electron transistors with the same physics, as one review article from Caltech researchers in 2005 points out. Still, as a system, what's important is that the flow of the fluid be controlled like it's important to control the flow of electrons and the current in logic circuits.

One way to control the flow of microfluidic channels is by a method called induced charge electro-osmosis, basically controlling fluid flow through voltages. This is where Yairi's paper comes in. He made a pump to increase flow rate and pressure in over half a million fluid channels using this property.

In the Tactus system, an actuator on the side controls the microfluidic flow through a voltage differential. Once the fluid is flowing, you can have pressure being applied at specific points on a deformable surface. That surface can be manipulated to deform into buttons and revert back to the flat surface once the fluid pressure is off. Tactus seems to have eventually got this down pat - it takes a second or so for the buttons to pop out and to merge into the surface.

Breaking Out

Tactus received $6 million in funding from Thomvest Ventures in late 2011. It has been a regular at the consumer electronics show to mostly positive reviews, and has reportedly showcased a prototype overlay for the iPad mini. Last year, the company reportedly worked on prototypes with Synaptics, the ubiquitous touchpad company. This year, it has announced a manufacturing partnership with Taiwan-based manufacturer Wistron, and Japan-based electronics supplier Ryoyo.

Platform Pitch

Automakers are apparently interested in the Tactus product from a safety point of view - for their dash panels. A tactile response prevents drivers from having to look at the panel and being distracted from the road.

Once you have a morphable surface, it is possible to have modes where different buttons pop out, say, for gaming and on-the-go-music. Tactus seems to have filed a patent for the programming logic of such a system.

Still, making the buttons grippy enough and having a clear surface panel at the same time may not be so easy.

To show why tactile is better, the company refers to a 2002 study done by Sony researchers on its website that shows speeds of scrolling for tactile feedback. The small but widely cited study found that users preferred the tactile response not so much for functional reasons, but because of better user experience. That might be key for Tactus.

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