Comparison Between Normal and Lateral Vibration on Surface Haptic Devices

2MoTac: Simulation of Button Click by Superposition of Two Ultrasonic Plate Waves

“…Therefore, this gives rise to the optimal value at which the plate should operate. However, for now we do not give an explanation for this specific behaviour; a modelling that takes into account the intermittent contact could be used for that aim [13].…”

Energy Analysis of Lateral vs. Normal Vibration Modes for Ultrasonic Surface Haptic Devices

“…However, lateral modes for friction reduction may also be interesting for several purposes, such as mechanical integration and noise reduction, and may be used additionally or in place of normal modes. The phenomenon of friction reduction with ultrasonic vibration has been thoroughly explored for 'out-of-plane' [6][7][8][9], or for combined vibration modes [10]. But the interaction mechanism through which friction is reduced with purely lateral vibration is less explored.…”

“…In [6], a simplified finger model, is used to explore the effects of lateral ultrasonic vibration on the grip function. In [7] this model is used to analyze the comparison between lateral and normal vibration modes, by measuring the perception of friction contrast for each mode at a set of vibration amplitudes, for a group of participants. With the test conditions explained in [7], the psychophysical measures indicate that the large majority of subjects are more sensitive to normal rather than lateral vibration modulation for a given value of wave amplitude, up to about 3 lm p-p , at frequencies around 30 kHz.…”

“…In [7] this model is used to analyze the comparison between lateral and normal vibration modes, by measuring the perception of friction contrast for each mode at a set of vibration amplitudes, for a group of participants. With the test conditions explained in [7], the psychophysical measures indicate that the large majority of subjects are more sensitive to normal rather than lateral vibration modulation for a given value of wave amplitude, up to about 3 lm p-p , at frequencies around 30 kHz. The measurements have also shown that the finger exploration speed affects significantly the result with lateral vibration, requiring larger amplitudes at higher speeds to produce the same perception.…”

“…The second experiment consists of a tribology analysis, which serves to link the vibration amplitude with the friction modulation. Additionally, the tribology analysis will help studying the effect of increasing the frequency, in comparison with the results presented in [7], and knowing whether the exploration speed continues to influence the result.…”