Industrial + Specialty Printing

Touchscreens and intermediate user interfaces with immediate tactile feedback should improve the usability and appeal of consumer electronic devices.

By Gail Flower

When it comes to making touchscreens, even on a flat glass, a button should look like a button, click like a button, and feel like a button to give the user a sensory awareness that everything works properly. Touchscreens and intermediate user interfaces with immediate tactile feedback should improve the usability and appeal of consumer electronic devices.

By combining the sense of touch with sound and sight, the user of touchscreens gets a much more natural experience. Artificial Muscle Inc. (AMI) is one company that focuses on haptic (touch) applications through the manufacture of actuator and sensing components and application of a proprietary technology platform called Electroactive Polymer Artificial Muscle (EPAM).

How does EPAM work? EPAM comprises a thin layer of dielectric polymer film between two conductive, compliant electrodes. When a voltage potential is applied across the electrodes, the Maxwellian pressure of the positive charge attracting the negative charge causes the electrodes to attract each other, and since the film is elastomeric and incompressible, the film contracts in thickness and expands in area. The technology works like an elastomeric capacitor that is capable of changing capacitance by applying a voltage or by an external mechanical force.

EPAM film turns into an actuator by attaching frames or materials that direct the motion to the desired axis. EPAM achieves motion (strain) from this electrostatic pressure as compared to other technologies. The displacement is a function of the area of EPAM, and the force exerted is a function of the number of layers of EPAM. The electrode layer of the EPAM can be patterned to achieve specific regions and directions of motions. The architecture along with configurations were developed and patented by SRI Int’l and are now licensed exclusively to Artificial Muscle, Inc.

In March 2010, Bayer MaterialScience LLC acquired Artificial Muscle, Inc. Bayer recognized the need for tactile, or haptic, feedback in consumer electronic products that use touchscreens—products such as portable gaming controllers, industrial controls, and casino games. The rumble packs common to hand-held game controllers are only able to produce simple, one-dimensional effects from a single frequency. The time lag felt as the motor spins up or down disassociates the feel from the event. With Bayfol Reflex, a printed, customized actuator technology, it is said that the results are real-time effects with high-fidelity feel.

What’s so special about artificial muscle? It’s quite like the difference between a 2D and 3D movie. You watch one and become part of the other. At the Consumer Electronics Show this year in Las Vegas, AMI Bayfol Reflex technology was integrated into the Morphie Pulse, a game grip for the fourth-generation iPod touch featuring haptic feedback and front-facing stereo speakers. The Morphie Pulse won two Best-in-Show awards by Gizmodo and Beatweek.
Let’s take it out of the game venue. Could a blind person be able to use an adapted smart phone when given touch responses? Could people who had specific fears (flying, falling, etc.) be able to face simulated situations through haptic responses? What other applications can fit? It will be interesting to see how many areas this will affect in the developing world of technology.