Improving contact realism through event-based haptic feedback

IEEE Transactions on Visualization and Computer Graphics (2006), pp. 219-230, doi: 10.1109/TVCG.2006.32
Experiments
Tasks
Findings

Does event-based haptic feedback provide higher realism than standard position-based feedback?

Variables and Constants

    Haptic Fidelity
  • haptic quality - acceleration matching, decaying sinusoid, fixed-width pulse, proportional, real materials
Constants

Height of the object being tapped, process of swapping blocks whether real or virtual

System Info

Displays
  • monitor - crt monitor used for text instructions
Input Hardware
  • haptic - phantom haptic device
  • keyboard - standard keyboard for entering realism ratings
Software
None

Headphones playing white noise to mask the sounds of tapping on samples; linear current amplifiers from Immersion Impulse Engine 2000 instead of the standard PHANToM amplifiers; Analog Devices ADXL150; National Instruments PCI-1200 card; ATI Mini-40 force sensor

Participant Info

7 participants had never used a haptic device, 7 had used a haptic device a few times, and 2 used haptic devices regularly.

Total # Age Range Gender Balance
16 19 - 33

Users used the PHANToM device, constrained to one degree of motion, to tap on sample blocks, 3 real and 9 virtual. Users had 5 seconds to tap on each sample, and then rated the realism of the sample on the computer screen. Each block was tested 3 times, for a total of 36 trials per user, presented in a random order.

Interaction and Environment

Interface

Users moved the PHANToM device pen in one axis (up and down) to tap the samples. Instructions were presented on the monitor and relayed through the user's headphones, which otherwise played white noise to mask any noise from the tapping. If too much force was used, the trial was repeated amongst the remaining random trials.

The environment only consisted of the real or virtual blocks, which were replaced by an operator between trials. The same process was done with a placeholder block in the virtual cases to prevent bias.

Dimensionality Scale Density Visual Realism
2.5D Small Low Low
Metrics

  • presence - users rated how much the sample felt like real wood on a scale of 1 to 7
  1. There was a significant direct effect of haptic quality on presence for a object manipulation task.

    Users rated the real sample of wood the most realistic, followed by real wood on foam. Acceleration matching provided the next most realistic ratings, followed by decaying sinusoid, then fixed-width pulse. Proportional techniques and the real foam sample

    Specificity: Somewhat general