In this blog post, we will focus on “The Potential and Challenges of Using 3D Printing in Mathematics Education for the Visually Impaired.”

Overview of 3D Printing

3D printing is a technology that builds physical objects—which can be touched by hand—by layering computer-designed 3D model data one layer at a time. This technology is hailed as a key driver of the Third Industrial Revolution, as it drastically reduces production processes and enables the creation of products that were previously impossible to manufacture using conventional methods. 3D printing is expected to be utilized in a wide range of fields, including not only manufacturing but also art, architecture, the military, and medicine. Furthermore, its potential for use in the education of the visually impaired has also been highlighted. Specifically, it can be used to produce tactile teaching materials needed for the education of the visually impaired.
3D printing consists of three main processes: modeling, slicing, and printing. First, the modeling process involves generating the 3D data required for printing. There are two methods for modeling: scanning an object using a 3D scanner or creating a model directly using 3D software. The creator must generate an STL file through this process. STL (Surface Tessellation Language) is a file format created to standardize existing 3D data formats; it is characterized by representing the surface of a 3D object using numerous triangular faces.
However, 3D printers cannot recognize STL files generated in this way directly. Therefore, a process is required to convert the STL file into a format that a 3D printer can recognize. The software that performs this role is called slicing software, and the output it generates is called G-code. The 3D printer uses this G-code to produce the actual printed object.
The most significant feature of 3D printing is that it is an additive process; unlike traditional manufacturing methods, it builds the product by layering material one layer at a time. The most representative additive manufacturing techniques include the SLS (Selective Laser Sintering) method, successfully developed by 3D Systems—founded by Chuck Hull in the United States in 1986—and the FDM (Fused Deposition Modeling) method, patented in 1989 by Scott Crump, the founder of Stratasys. SLS and FDM are the two manufacturing methods currently adopted by most commercially available 3D printers.
First, an SLS 3D printer selectively fires a laser at powder spread across the build plate to sinter, or fuse, the particles together. SLS is a process that builds up layers by repeatedly performing this step. The FDM method is even more widely used; it involves feeding a thermoplastic material (a material that softens when heated, typically plastic) through a nozzle in the form of a thin filament and extruding it layer by layer, much like spinning yarn. SLS and FDM are already the most commonly adopted methods in 3D printing, and with the recent expiration of related patents, they are expected to capture an even larger market share in the future.

Applications in Mathematics Education for the Visually Impaired

3D printing, which has opened new horizons in the manufacturing sector by adopting additive manufacturing methods, holds great potential for application across various fields. While it appears applicable to most existing industries, this section will focus on its use in the relatively under-explored field of education: specifically, mathematics education for the visually impaired.
Generally, mathematics education for the visually impaired often faces significant challenges. The difficulties in the classroom are particularly pronounced in mathematical fields that rely heavily on visual elements, such as graphing. However, there is an argument that, provided the appropriate educational conditions are in place, visual impairment can actually serve as an advantage in mathematical research, particularly in fields such as geometry and topology. Bernard Morin, a French differential geometer, achieved significant accomplishments in geometry and topology despite being visually impaired. Citing this example, Russian scientist Alexei Sosinski argues that visually impaired individuals excel in certain areas of geometry compared to sighted people. The reason given is that while the brains of sighted people perceive three-dimensional shapes as images projected onto a two-dimensional retina—which inevitably imposes limits on precise thinking—this is not the case for the visually impaired. Although the visually impaired are considered to possess such great mathematical potential, the current conditions for their mathematics education are quite poor.
The biggest challenge in mathematics education for the visually impaired is how to help students understand graphs. Existing tactile teaching materials have traditionally presented graphs as patterns of dots. However, this format poses significant production difficulties. Since it does not use standard Braille characters, the time and cost required to produce Braille books increase exponentially.
Another issue is the inconvenience encountered during instruction. When a teacher explains examples other than those presented in the textbook, this can be easily resolved through simple board writing in mainstream education, but it is impossible in the education of students with disabilities. Since it takes a long time to produce new tactile teaching materials, teachers are forced to rely solely on the existing tactile materials. The time and financial difficulties involved in producing tactile teaching materials, along with the limited variety of available materials, can be considered the two main problems.
One study applied 3D printing to address this issue. 3D printing is highly suitable for solving the problems mentioned above. Since 3D printing allows for the easy production of any model using a relatively inexpensive 3D printer, it saves both time and money compared to outsourcing to external vendors. The range of available teaching materials is also virtually unlimited. This is because, with just a single 3D printer, any type of model can be printed by modifying an STL file.
In this study, we developed a program using the 3D modeling software Blender and the slicing software Cura that automatically generates an STL file of a corresponding graph when a mathematical function is entered. Based on this, we printed tactile teaching materials and conducted a study involving actual classes at a school for the blind to gather feedback. As a result, both teachers and students evaluated the introduction of these supplementary teaching materials into mathematics education positively and reported that they aided in effective understanding during the teaching and learning process.
However, several issues were identified that need to be addressed, such as the fact that 3D printers are not yet widely available in schools for the blind, and that although the 3D model creation process was simplified as much as possible, there remains a relatively high barrier to entry for the general public unfamiliar with 3D software.
As 3D printers demonstrate potential for application in various fields and are identified as key players in future industries, they are expected to play a significant role in the field of education for the visually impaired as well. Although there is still room for improvement in terms of adoption rates, precision, and ease of use, experts predict that these technical issues will soon be resolved and that an era will arrive when 3D printers are widely available in homes and institutions. If this happens, there is hope that 3D printing technology will evolve from being a key player in future industries into a “warm technology” that addresses educational challenges for people with disabilities who are often marginalized.