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3D-printing accessibility

Tactile Access and The 3D-printing Process

This post discusses the 3D printing process and its potential to enhance tactile experience for blind people. There is a critical resource shortage where tactile graphics are concerned, and 3D printing is a technology that can help to bridge the gap. I strongly encourage the interested reader to access the resources linked here for more details.

Robert Jaquis Writing in the Braille Monitor (April 2012), explained the problem this way. “Sighted students have access to a wide variety of images in books, videos, and the Internet, but blind students must rely on text or verbal descriptions or the occasional tactile graphic.”

He explained that tactile 3-dimensional replicas are particularly useful for conveying the shape of exceedingly small, or extremely large, objects. I strongly agree with this statement.

Once, I examined a 3D-printed replica of the DNA helix. It was about 2 inches long, and I held the replica in one hand tracing the spiral shape with the fingers of my other hand. In that moment, I finally understood the description of the DNA molecule as a “twisted ladder”.

I am sure that I had read or heard the words “spiral” and “ladder” used to describe the structure of the DNA molecule before examining the 3D-printed replica. However, I did not intuitively make the connection between the description of the DNA molecule and the physical spiral shape of the double helix until I had time to explore a tactile representation of it.

I will return to this powerful idea near the end of this post. For now, I will discuss the 3D printing process and link to examples of projects that can increase tactile access for blind people.

An Overview of the 3D-Printing Process

There are three steps to producing a 3D-printed replica of an object.

•            Scanning the physical object and saving data in a digital file

•            Creating a 3D model of the object

•            Sending the 3D model to a printer that creates a physical replica of the object

In this process, a physical object is converted into a digital model that can be viewed on a screen. Tactile access can only be achieved by sending the 3D model to a 3D printer that produces a physical replica of the object.

Many individuals and organizations have completed the first two steps of the process—scanning objects and using that data to create 3D models of the scanned objects. The models can be viewed online or downloaded to be sent to a 3D printer.

Check out my post about finding 3D models on the web.

Notes About the Accessibility Challenges of Using 3D Modelling Software

Computer-aided design (CAD) software lets people create   3D models.

In some instances, blind people who access computers with screen readers, that provide voice output, can access features of these CAD software packages from a text-based command line.

For example, OpenScad is a free software package for creating 3D models. Claire Kearney-Volpe  created this curriculum that shows how some features of the software package can be used with a screen reader.

Here is another useful resource for learning OpenScad. link

However, researchers at Stanford’s Shape lab wrote this paper Explaining one drawback to using OpenScad.  Although The program has a text-based command line for inputting measurements, the output is displayed as a visual graphic on a computer screen. These researchers prototyped a design in which a blind person receives a tactile representation of the model on a refreshable braille display connected to the computer.

The team at Tactile Universe uses a different CAD software package called Blender to create and print their 3D models. Read these technical blog posts to learn more about their process.

A quick google search indicates that people can create 3D models in Blender using the python programming language. Read this manual for instructions.

Not all cad software packages have functionality with a screen reader. In my opinion, Tinkercad  is not accessible because there are many unlabeled buttons on the home page. The designers did not label their buttons properly with alt-text, and so I did not create an account or evaluate their 3D modelling tools.

Printing 3D Models and Creating Physical Objects

Blind people benefit from the last stage of the process when a 3D model becomes a physical object that can be touched.

To do this, the 3D model is exported to a stereolithographic (STL) file that contains detailed instructions for the material to be extruded by the printer.

Here is a step-by-step guide for exporting a 3D model into an stl file.

Here are two more examples of how 3D printing can be used to increase tactile access for blind people.

Mike kolitsky wrote this paper that showed how 3D printing can be used to create physical replicas of digital learning objects, so blind students can have access to visual material presented online as images. Examples of 3D Prints made from 2D photos are at the end of his paper.

More recently, two co-authors and I wrote a paper describing another way to access information about 3D replicas. We attached QR codes to 3D-printed replicas of stone projectile points (arrowheads). Scanning these QR codes with a smartphone prompted the user to access a webpage with more information about each projectile point.

I know that many people are exploring the educational benefits of 3D-printing, and I expect to learn of other projects in the future. Meanwhile, I hope that the resources that I have gathered here will be useful in this endeavor.

Categories
3D-printing

Finding 3D models

This post is part of an ongoing series covering aspects of 3D printing from scanning objects, to creating digital 3D models, and then printing the digital files as physical 3D replicas. As I explored this topic, I collected links to many outstanding resources.

•            People who have access to a 3D printer can browse online libraries for downloadable files.

•            People who do not have access to a 3D printer can check out organizations that will print and ship 3D-printed replicas to them.

online libraries containing digital 3D models

Here is a list of online libraries that offer 3D models downloadable as digital files that can be sent to a 3D printer. Many of these links were recommended by members of the Tactile Art and Graphics Specialist, TAGS mailing list during December 2019. Thanks everyone!

Sites that offer 3D models in multiple categories

sketchfab

Thingiverse

My Mini Factory

3D models uploaded by specific organizations

Some organizations maintain online libraries of models that are specific to their area of expertise.

NASA offers printable models of space craft including rockets, rovers, shuttles, and the International Space Station. For more information, read this post about searching the NASA library for a model of the Perseverance Rover.

The Smithsonian 3D digitization database contains models of many different objects from animal skulls to presidential portraits, and much more. The models can be viewed onscreen or downloaded as printable files.

The National Institutes of Health (NIH) offers biomedical 3D printable files and 3D printing resources.

organizations that will print and ship 3D-printed replicas

Some services will print and ship 3D replicas to individuals upon request. The examples below highlight paid, or free, models.

The Shapeways marketplace offers prints searchable by category including jewelry, phone cases, tabletop game accessories and more. The company uses industrial-grade printers and offers models in several types of plastic or other materials like steel, bronze, brass, silver, gold, wax, porcelain, or aluminum.

Kraftwurx Is a company that serves 3D designers. It lets them upload files, specify materials, and order prints that can be sent to their customers.

See3D  is a non-profit organization that organizes the printing and distribution of 3D printed models for people who are blind.

final thoughts

Many organizations maintain online libraries of 3D models. Some make downloadable files available, and others also ship physical 3D-printed replicas. Anyone seeking a specific model can search the sites listed here or search the web for other sources.

Categories
accessibility

Planning Accessible Virtual Events

In the time that we have been at home to limit the spread of covid-19, I have attended three online conferences, presented in a webinar, and had numerous zoom calls. Even as we re-open, I expect online meetings to continue to be common. I am sharing resources with information on planning virtual events that are accessible to people with disabilities. This list of helpful links was prepared by Robin Marquis, an Accessibility in the Arts Consultant who works in Baltimore and Washington D.C.

Resources

Rooted Rights: How to Make Your Virtual Meetings and Events Accessible to the Disability Community

National Endowment for the Arts: Resources to Help Ensure Accessibility for your Virtual Events for People with Disabilities

https://www.arts.gov/accessibility/accessibility-resources/resources-to-help-ensure-accessibility-for-your-virtual-events-for-people-with-disabilities

Cooper Hewitt Guidelines for Image Description

https://www.cooperhewitt.org/cooper-hewitt-guidelines-for-image-description/

National Center on Disability and Journalism: Disability Language Style Guide (available in Spanish and English)

We presented this Online Inclusion Webinar for the Peale Center for Baltimore History and Architecture. The video is near the bottom of this events page under the heading for online lectures and webinars.