Vibrotactile perception: examining the coding of vibrations and the just noticeable difference under various conditions

Abstract

High-frequency vibrations are an essential part of numerous manipulation tasks. A promising research area, in particular, are telemanipulation tasks where vibrations occurring in the remote environment are fed back through tactile displays. Three experiments concerning the perception of vibrations were conducted. The first experiment aims at determining whether vibrations are coded primarily by frequency, amplitude, or acceleration by human participants. Results show that primarily frequency and amplitude, but not acceleration of the vibrations were perceived. In the second experiment, participants' just noticeable difference (JND) for frequency under different conditions was examined. The resulting JND of 18% for frequencies showed dependence neither on the amplitude or acceleration, which were independently held constant, nor on the reference frequencies. Therefore, it is not necessary to adjust the subjective intensity for vibrations for each human operator when designing and using tactile displays. In the third experiment, the stimuli and the procedure of the second experiment were replicated using different configurations and a mere force-output device. The resulting JNDs were 21% for vibrations of 100 Hz, and 17% for vibrations of 150 Hz and above. Furthermore, there was no visual dominance over the haptic modality regarding the JND for frequencies.

Refined methods for creating realistic haptic virtual textures from tool-mediated contact acceleration data

“…These models must also feel correct to the user. In order to accomplish this objective of haptic realism, we believe the model must be able to match the frequency content of the data in both amplitude and spectral shape, which is supported in [22].…”

“…Romero et al [25] calculated that GFC = 0.90 corresponds to a reconstructed spectrum with 19% less energy than the original data. Therefore, since the just noticeable difference (JND) for vibrations greater than 150 Hz has been experimentally determined to be 17% [22], it is reasonable to expect that GFC > 0.90 will result in a model with a good frequency match. The exact threshold would need to be determined through extensive psychophysical testing.…”

Haptics in Music: The Effects of Vibrotactile Stimulus in Low Frequency Auditory Difference Detection Tasks

“…For example, the expected tactile only JND of a 150 Hz sinusoidal stimulus with the amplitude held constant has been measured as ± 18% (27 Hz) of the fundamental [31], equating to 28.8 Hz at 160 Hz. In addition, in an auditory only JND experi- ment there would be expected a 3 Hz variation in JND for sinewave and 1 Hz for complex waveforms below 500 Hz [32].…”

Sensor-Actuator Supported Implicit Interaction in Driver Assistance Systems

“…As it is established that the perceived intensity of vibration varies as a function of both frequency and amplitude (shown in Fig. 11.4), the intensity of a stimulus is most often coded by variation of frequency only [361] (e. g. because of the ease of implementation, particularly when using low-cost cell phone motors). However, if the amplitude of a vibration is changed while the frequency is kept constant, a noticeable change in the stimulus would occur (as expected) [362, p. 9].…”