Issue No. 04 - October-December (2011 vol. 4)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TOH.2011.21
As touch based input becomes more popular in mobile devices, there is an increasing need for haptic feedback on key-less input surface. Four experiments were conducted to design and evaluate identifiable emulated key-click signals using a piezoelectric actuator. Experiments I and II assessed the information transmission capacity for the amplitude, frequency, and number of cycles of raised cosine waveforms used to drive the piezo actuators under fixed- and roving-background conditions, respectively. Experiment III estimated the total information transfer for all three parameters. The results were used to reduce the number of stimulus alternatives in the key-click signal set with the goal to achieve perfect identification performance. Experiment IV verified that up to 5 to 6 identifiable key-click signals could be achieved with the experimental setup. The present study outlines an information theoretic approach to conducting identification experiments to guide the design of and to evaluate a perfectly identifiable stimulus set. The methodology can be applied to other applications in need of perceptually identifiable stimulation patterns.
Haptic interfaces, Mobile handsets, Piezoelectric actuators, Object recognition, Information processing, Mobile communication, Feedback control
"Design and Evaluation of Identifiable Key-Click Signals for Mobile Devices", IEEE Transactions on Haptics, vol. 4, no. , pp. 229-241, October-December 2011, doi:10.1109/TOH.2011.21