No abstract

No abstract

A realistic keyclick sensation is a serious challenge for haptic feedback since vibrotactile rendering faces the limitation of the absence of contact force as experienced on physical buttons. It has been shown that creating a keyclick sensation is possible with stepwise ultrasonic friction modulation. However, the intensity of the sensation is limited by the impedance of the fingertip and by the absence of a lateral force component external to the finger. In our study, we compare this technique to rendering with an ultrasonic travelling wave, which exerts a lateral force on the fingertip. For both techniques, participants were asked to report the detection (or not) of a keyclick during a forced choice one interval procedure. In experiment 1, participants could press the surface as many time as they wanted for a given trial. In experiment 2, they were constrained to press only once. The results show a lower perceptual threshold for travelling waves. Moreover, participants pressed less times per trial and exerted smaller normal force on the surface. The subjective quality of the sensation was found similar for both techniques. In general, haptic feedback based on travelling ultrasonic waves is promising for applications without lateral motion of the finger.

This article presents a method for estimating the parameters of a biomechanical impedance approximation model for a finger interacting with a rigid beam vibrating outof-plane at ultrasonic frequencies, and illustrates correlation results of these parameter magnitudes with vibration amplitude friction modulation detection threshold.

This paper aims to investigate the semantic perceptual space of synthetic tactile textures rendered via an ultrasonic based haptic tablet and the parameters influencing this space. Through a closed card sorting task, 30 participants had to explore 32 tactile-only textures and describe each texture using adjectives. A factorial analysis of mixed data was conducted. Results suggest a 2 dimensional space with tactile textures belonging to a continuum of rough to smooth adjectives. Influence of waveform and amplitude is shown to play an important role in perceiving a texture as smooth or rough, and spatial period is a possible modulator of different degrees of roughness or smoothness. Finally, we discuss how these findings can be used by designers on tactile feedback devices.

No abstract

In this article, several modes are controlled simultaneously both in phase and amplitude on an haptic display. To achieve this, modulation/demodulation control combined with mixed spatial/frequency filters is developed. It is then applied to produce a predefined velocity field both in space and time on a plate. The experimental results show good agreement with theory.

No abstract