Tactile Schematics – Accessibility

Tactile Schematics

Idea

Thesis research of standards and best practices for designing tactile schematics for nonvisual circuit building.

Thesis Advisors

Role

Research, accessibility design, experience design, 2.5D design and prototype production

Go to video transcript

Research Question

How can we make electronics more accessible to people who are blind or low vision?

Problem

Circuit Descriptions

Schematics are an integral part to learning electronics. They are drawings of the relationships between components in an electronic device and are used to build circuits (as simple as a project made at ITP to the complexity of a laptop). While sighted readers rely on schematic images to understand how electronics work, low vision and blind readers rely on circuit descriptions.

The recording below is called a circuit description. It can be read with a screen reader, either through synthesized speech (the example I’ve provided) or a Refreshable Braille Display. Blind and low vision learners rely on them to understand circuits.

VoiceOver (a screen reader) reading a circuit description

Go to transcript

Ok, now can you draw that circuit? I’ll wait! This is the circuit the screen reader was describing.

Obstacle

As you heard from the screen reader recording above, it’s tough to understand a circuit from a description, especially if you’re a beginner. No tactile graphical representation has yet been able to compete with circuit descriptions.

Electronics beginners can benefit from the spatial information schematics provide and learn the relationships of the components through touch.

Related Work

Educational Tools

There are options for low vision and blind readers with different learning styles: verbal descriptions or interactive simulations for auditory learning, Braille translations for reading/writing learning, blind Arduino workshops for constructivist learning, and tactile graphics for kinesthetic/tactile learning (the focus of this research).

Educational Resources

Tactile graphics are one element in a larger toolbox. The Blind Arduino Project develops and shares techniques for low vision users to build electronics projects. The Andrew Heiskell Braille and Talking Book Library hosts Arduino workshops with the Dimensions program, using tactile methods to learn hardware and software. The Smith Kettlewell Technical File was a publication for Blind or Low Vision electronics enthusiasts and used standardized verbal circuit descriptions instead of diagrams.

Personas

Persona for Amanda, textual description link below

Textual description of persona 1

Persona for Eric, textual description link below

Textual description of persona 2

Persona for Jo, textual description link below

Textual description of persona 3

Experience Map

Experience map of a user interacting with tactile schematics.
Timeframe Homework is assigned Homework is started Homework is unfinished Homework is overdue
Activities Opens class site and finds the lab is due Can’t understand the circuit description Has to keep replaying the circuit description Gives up and moves on to the remaining content
Touch Points Phone/laptop Phone/laptop Phone/laptop Phone/laptop
Emotion Line Optimistic Curious Frustrated Hopeless
Pain Points Needs to keep up with the demanding course load Has limited resources for understanding circuits Circuit descriptions are hard for beginners Feels like none of the options are for him
Ideas for Improvement Add other learning style resources to class site Link from class lab to resources presented in another format Schematics are converted to tactile schematics as SVGs Have resources available ahead of the lab due date

User Flow

Close up of hands tapping a schematic on an iPhone.
Eric opens up the Physical Computing site on his phone to see what homework is due. He uses his screen reader to navigate to the lab and listens to the circuit description of how the Arduino should be set up.
Swell Touch Paper being fed through a Swell Form Machine.
He prints the schematic on Swell Touch Paper and runs through a Swell Form Machine. The black Braille and outlines of the schematic puff up.

Hands tracing an imaginary circuit on a desktop.
He sort of understands the circuit descriptions, while tracing the outline of how it might look with his finger on the table. However, he keeps having to play it over and over again,.

Hands exploring a tactile schematic.
He feels the raised surfaces and builds a mental picture. He gets his Arduino out and hooks it up, periodically reaching over and double checking with the tactile schematic to make sure he has the right pin connections.

Hands tapping a smartphone screen and downloading a file.
He continues listening and hears that there also is a tactile schematic available for download. He tabs over to the link to download an SVG of the schematic and is relieved to have another resource.

Finger pressing a button on a breadboard with a piezo.
The piezo buzzes when he presses the button and he can’t wait to show his teacher and classmates that it worked.

Solution

A set of design standards and best practices were developed to illustrate how to design a readable tactile schematic. These standards were then applied to the 50+ schematics from the Physical Computing site. The standards and best practices and book of tactile schematics were made available for download by the public.

Prototyping

Original analog in circuit as displayed on the NYU website, not optimized for tactile perception
Original file: Analog In as downloaded from the Physical Computing site. It is tiny, there’s text, and some of the lines are gray so they won’t puff up in the Swell Form Machine.

1st iteration of analog in tactile schematic with the key on the same page and poorly designed schematic symbols
Version 1: First iteration of Analog In. The entire layout is much too cluttered, the gray text color contrast ratio is 3.03:1, which is not accessible, the Braille plus sign is incorrect, and the size of the components aren’t yet optimized using HCD.

11th iteration of Analog In tactile schematic with braille, high contrast text labeling, and optimized symbol sizing
Version 11: Final iteration of Analog In, in which the layout has been rotated to avoid clutter, the text color has been changed to a 10:01 color contrast ratio, but still won’t puff up on the Swell Form, the Braille plus sign has been corrected, the symbols have been optimized from user feedback, and the slash mark adheres to upper right-hand corner conventions.
Manual feed tray in a color laser printer ejected and loaded with Swell Touch Paper.
Paper is loaded so that it prints on the sticky, coated side of the paper.

Close up of Swell Form Machine dial set to Medium.
Test printing helps determine the best heat setting for the paper and heater you’re using.

Swell Touch Paper being fed through a Swell Form Machine.
The paper is inserted, following the direction of the arrow, the carbon in the black ink reacting to the heat and puffing up.

Research Method

In order to determine the optimal design standards and best practices for tactile schematics (labeling, scaling, layout, and contrast), a usability study was conducted through NYU’s IRB with 5 low vision and blind participants, ranging in learning style, finger variables (sensitivity and size), electronics experience, Braille literacy, and level of vision. Readers were presented with tactile versions of The Big 6, or the six schematics crucial to understanding Physical Computing, given informed consent, a series of tasks, asked to identify specific electronics components, and explain the schematic in their own words.

Hands exploring the schematic of an LED, Resistor, Regulator in Series during a usability test.
Hands touching common component symbols and reading the Braille label to the right of it.
Hands pointing to elements, and tracing large high contrast text labels of an Analog In schematic.

Usability Questions

Introduction (5 min)

  1. Tell me about your experience with electronics?
  2. Tell me about your experience with tactile graphics?

Phase 1, Using the Site (15 min)

  1. Go to this site and have a look at the page.
  2. I’m going to send a circuit description to your email for you to listen with your screen reader.
  3. What is title of the schematic?
  4. Will you find the resistor?
  5. Can you tell what kind of resistor is depicted?
  6. Will you tell me many LED’s are shown here?
  7. Can you see if you can tell where is ground located?
  8. How would you explain the schematic back to me in your own words?

Phase 2, Using the Tactile Schematics (20 min)

  1. What is title of the schematic?
  2. Will you find the resistor?
  3. Can you tell what kind of resistor is depicted?
  4. Will you tell me many LED’s are shown here?
  5. Can you see if you can tell where is ground located?
  6. How would you explain the schematic back to me in your own words?

Follow Up Questions (10 min)

  1. Which is more clear to you? Which do you prefer, the circuit descriptions or the tactile schematics?
  2. How do you feel about the material you’re seeing here?
  3. What are your thoughts about the tactile graphics?
  4. Do you have any suggestions for the design of these graphics?
  5. Do you see any other uses in  your life for tactile graphics?

Conclusion

  • There is no perfect solution for designing tactile schematics. It’s a process and all the things I made are a part of that process. The only thing I could do was make my process available to other designers with a Style Guide.
  • How do we evaluate tactile graphics? One project at a time? 
    • Because their effectiveness isn’t universal, I would always have to tailor them to the audience I’m designing them for. For example, one user might prefer Braille, one might prefer high contrast ratio text.
  • I had so many resources, participants, and advisors, and I still can’t be totally certain they’re as effective as circuit descriptions.
  • Can these tactile schematics go beyond simply understanding how a circuit works to actually hooking one up? 
    • This is the beginning stage of much larger scope of work to see if we can develop a non-visual workflow for building circuits.
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