Audio-Tactile Graphics in an Adaptive Delivery System for Math Tests and Instruction

Presentation by Eric G. Hansen, Steven Landau, Valerie J. Shute, and Edith Aurora Graf

This material is based upon work supported National Science Foundation under Grant No. 0313202: Valerie J. Shute, Eric G. Hansen, & Edith Aurora Graf - Co-principal Investigators

The Need

There is a great need to make complex math content accessible to individuals with severe visual impairments

  • Charts and figures
  • Tables
  • Math expressions

Two Approaches

  • Descriptions
    • Live reader
    • Prerecorded audio
    • Synthesized speech
    • Braille
  • Pictures
    • Tactile media
  • ACED project

    • Adaptive Content for Evidence-based Diagnosis
    • Uses 8th grade math content in the topic of "sequences"
    • For students with and without visual disabilities

    An ACED item

     A complicated math problem with a chart and graphics.


    Talking Tactile Tablet (TTT)

    Overlay sheet for ACED for TTT
    with item-specific content

    Overlay sheet for TTT of the above math problem. 


    • 4 students (including 3 users of screen readers)
    • About - hour of use of ACED for TTT by each participant
    • 11 items
      • 7 multiple choice
      • 4 constructed response
      • Only one item required no TTT graphical treatment
  • Found generally positive reactions to the usability
  • Pre-pilot administration utility: Allows the administrator to pick which items to administer and in what order

    Page view of the sequence administration 

    Coming Next: Pilot Test

    • About 170 items (with instructional feedback)
    • Major delivery mechanisms
      • Mainstream ACED
      • Screen Enlarged ACED
      • ACED for TTT
  • Macro-adaptive - adjustable to the access needs and preferences of student
  • Micro-adaptive - capable of selecting, after each item is administered, an item from remaining pool that will be most informative for measuring the students' abilities.
  • Three administration options:

    • Mainstream ACED
    • Screen magnified ACED
      • Set screen magnification preferences
    • ACED for TTT
      • Set TTT preferences

    Some graphics can be simplified:

    Dustin receives a mysterious looking tree as a housewarming gift.  He plants the tree in his garden.  Each year the tree grows new shoots.  The pictures above show the pattern of growth across the years.  Observe the first four years of growth.  Assuming the same pattern continues, how many new shoots appear in year ten?

    Removal of the extremely complex diagram (too many tree shoots to count):

    Original image of tree growth.

     Tree growth image changed for tactile graphic.  Year 11 may be omitted.

    Another complex graphic (too many small triangles):

    The pictures below show a fractal "Sierpinski's Triangle" at four different stages.  Notice that a new set of black triangles appears at each stage.  For example, the third stage shows nine new black triangles.  How many new black triangles appear at stage 6?

    Possible revision to graphic for tactile format (avoid changes in scale):

    Shows original triangle image.

     Triangle images enlarged for tactile graphic, but in scale.


    Audio-tactile graphics may provide a platform for leveraging advances in computer and related technologies for improving access to math by individuals with severe visual disabilities
    Accessibility features such as audio-tactile graphics may prove to be a useful part of an adaptive system capable of addressing the needs of individuals both with and without visual disabilities