Smoothed Pointing

smoothedSmoothed Pointing is a velocity-based precision enhancing technique for remote pointing via absolute input devices. Differently from other similar pointing enhancement techniques, Smoothed Pointing takes advantage of a model that relies on the visual acuity theory to configure some parameters of the filter in an automatic way so as to better fit with user and device characteristics. The user is requested to execute a 10-second dwelling task, namely to try to keep the cursor steady on a target visualized on the screen. Then the logged data are used to configure the filter so as to decrease the jitter due to noise in the device signal or to hand tremor.

Smoothed Pointing adopts a velocity-based C-D ratio adaptation to smooth the cursor movement. It uses two speed thresholds to determine the gain value: a minimum speed vmin below which any motion is considered a tracking error; and a maximum speed vmax, which is the hand speed at which the offset recovery is automatically triggered. In fact, if a user moves slowly, the gain scaling produces the accumulation of an offset between the device position in the motor space and the cursor position in the display space. This offset, the maximum value of which is limited to dmax, is recovered by setting the C-D gain to gmax. To smooth the cursor movement, in the [ vmin, vmax ] interval, a modulated sine wave is used as the gain damping function.

Publications

  • L. Gallo and A. Minutolo, “Design and comparative evaluation of Smoothed Pointing: A velocity-oriented remote pointing enhancement technique,” International Journal of Human-Computer Studies, Vol. 70, Issue 4, pp. 287–300, 2012. doi:10.1016/j.ijhcs.2011.12.001.
  • L. Gallo, M. Ciampi, and A. Minutolo, “Smoothed Pointing: a User-Friendly Technique for Precision Enhanced Remote Pointing”, in CISIS 2010: Proceedings of the International Conference on Complex, Intelligent and Software Intensive Systems, (Los Alamitos, CA, USA), pp. 712-717, IEEE Computer Society, 2010. doi:10.1109/CISIS.2010.76