Acoustic levitation uses acoustic radiation forces to counteract gravity and suspend objects
in mid-air. Although acoustic levitation was first demonstrated almost a century ago, for a …

The coefficient of friction of most solid objects is independent of the applied normal force
because of surface roughness. This behaviour is observed for a finger pad except at long …

Ultrasonic vibration is employed to modify the friction of a finger pad in way that induces
haptic sensations. A combination of intermittent contact and squeeze film levitation has been …

Ultrasonic vibrations of a plate can modify the perception of the friction between a surface
and a sliding finger. This principle, coupled with modern position sensing techniques, is able …

In part 1 of the current study of haptic displays, a finite element (FE) model of a finger
exploring a plate vibrating out-of-plane at ultrasonic frequencies was developed as well as a …

In Variable Friction Tactile Displays, an ultrasonic standing wave can be used to reduce the
friction coefficient between a user's finger sliding and a vibrating surface. However, by …

The distinct tactile feedback provided by mechanical keyboards notifies users that their
actions have been successfully recorded. The presence of these subtle yet informative …

To render tactile cues on a touchscreen by friction modulation, it is important to understand
how humans perceive a change in friction. In this study, we investigate the relations between …

Electrovibration tactile displays exploit the polarisation of the finger pad, caused by an
insulated high voltage supplied plate. This results in electrostatic attraction, which can be …

We observed the dynamic interaction between a fingertip and an ultrasonically vibrating
plate using Laser Doppler Vibrometry in order to investigate the causes of ultrasonic friction …