Designing auditory displays to facilitate object localization in virtual haptic 3D environments

Proceedings of the 8th international ACM SIGACCESS conference on Computers and accessibility - Assets '06 (2006), doi: 10.1145/1168987.1169042
Experiments
Tasks
Findings

How effective are audio cues alone in helping visually impaired users to search a virtual environment?

Variables

Independent Variables
  • amount of cube nodes - amount of cube nodes placed in the virtual environment, between 3 and 8.
  • location of cube nodes - where the cubes were placed in the virtual environment, somewhere inside a large box.
  • audio cues - various types of audio cues were presented to indicate position of objects.
System Info

Displays
None
Input Hardware
  • phantom desktop - haptic stylus for navigation and grip input in an environment and for receiving force and tension feedback.
Software
None

Participant Info

Except one female who had low vision (10/100), all participants were blind.

Total # Age Range Gender Balance
7 26 - 59

Search through the virtual environment when given varying audio cues to determine how many cube nodes were present within the virtual environment.

Environment

Dimensionality Scale Density Visual Realism
3D Small Medium Low
Metrics

  • time - measuring how long it took a user to determine the amount of cubes present.
  • errors - comparing how accurate the user was in determining the amount of cubes present to the actual number.
  1. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information task.

    Sonifying the x,y,z-coordinates of objects did not successfully aid users in finding them. The characteristics of sound (pitch, panning, high-pass filter) that were mapped to the position of an object lack resolution and don’t provide absolute values. The

    Specificity: Somewhat general

  2. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information and travel - exploration task.

    Using discrete cues to represent the direction of objects is useful. It takes some time for a new user to recognize and make use of the cues, but they then provide an unambiguous direction. Integrating discrete directional cues into an auditory display ca

    Specificity: Neither

  3. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information and travel - exploration task.

    An increasing rhythm to represent the distance between the cursor and an object appeared intuitive. Users easily perceived when they moved the cursor nearer to an object. Using rhythm to represent distance can be a valuable option when combining it with a

    Specificity: Neither

  4. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information and travel - exploration task.

    Positioning virtual sound sources at the location of virtual objects creates a natural/realistic auditory space. The use of such a method is very intuitive and requires little cognitive effort by the user. The time to find-and-touch objects was on average

    Specificity: Neither

  5. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information task.

    With some practice and explanation the users were able to successfully use the stylus of the PHANToM Desktop as a pointing device. It took some time and ‘luck’ to discover all the objects present, but when an object was discovered, users had little troubl

    Specificity: Highly general

  6. There was a significant interaction between amount of cube nodes, location of cube nodes, and audio cues on time for a comprehension of spatial information task.

    The users reacted positively to haptic magnetism. Some tasks were completed amazingly fast, but some similar tasks took a long time to complete or were not completed correctly. It was reported that haptic magnetism, despite the attractive forces being wea

    Specificity: Somewhat specific