Issue No.04 - October-December (2011 vol.4)
Hsiang-Yu Chen , Motorola Corporation, Libertyville
Steve Dai , Sandia National Laboratories, Albuquerque
Hong Z. Tan , Purdue University , West Lafayette
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.
Mobile applications, haptic feedback, key click, human information processing.
Hsiang-Yu Chen, Steve Dai, Hong Z. Tan, "Design and Evaluation of Identifiable Key-Click Signals for Mobile Devices", IEEE Transactions on Haptics, vol.4, no. 4, pp. 229-241, October-December 2011, doi:10.1109/TOH.2011.21