Blog - Paper Reading #14

TeslaTouch: Electrovibration for Touch Surfaces

Authored by Oliver Bau, Ivan Poupyrev, Ali Israr, Chris Harrison.


The authors are all researchers at Disney Research in Pittsburgh with the exception of Chris Harrison who is a PhD student at Carnegie Mellon.


Summary

Hypothesis
The authors hypothesized that electrovibration could be an effective technique to provide tactile feedback for touch surfaces.

Methods
 Electrovibration was generated by sandwiching a transparent electrode between a glass plate and a resistive sheet. Several tests were conducted measuring baselines for this technology. 10 users participated and recorded results including absolute detection thresholds, amplitude and frequency discrimination thresholds, as well as simply characterizing the "feel" of different settings.

Result
Low frequency stimulus resulted in the surface feeling rougher as opposed to higher frequencies that felt smooth. High amplitudes caused the surface to feel more waxy as opposed to rubbery or sticky. One observed characteristic was that users did not interpret the sensation strictly as changing friction, they were able to detect both an element of friction and vibration simultaneously.

Content
The paper describes the prior work the project is based on, including the discovery of electrovibration. It then describes the physical setup of the surfaces utilizing TeslaTouch. The authors then conducted a user study to examine the baselines of electrovibration, as well as the general user response to the tool. The results led to an examination of the advantages this technique has over mechanical actuation. The authors conclude by examining potential uses for the product.

Discussion
I found the paper quite interesting. I think that the authors achieved their aim in proving electrovibration as an effective means of tactile feedback. The bit at the end of the paper about the parallel technology  being developed outside their labs seemed sketchy. Otherwise the project seems a solid academic development with real world applications.
It is interesting that this design has no actual moving parts. The authors give a very good argument for this quality. Moving parts all break down eventually. I see no limit to the uses for this product. Tactile feedback would be in some way useful for most all tasks on an interactive surface. As for future work, I would like to see the team work around the issue of only allowing one finger in motion at one time.