Creating refreshable displays that are accessible to blind and visually impaired people
Blind and visually impaired people rely on Braille as a key method of reading, learning and acquiring knowledge. Yet there are limitations in terms of access to Braille, and regarding the amount and type of information that can be translated into Braille. PhD student Tigmanshu Bhatnagar has created an affordable, refreshable display technology that can relay Braille and graphical information to users in a single device.
Braille has been used since the 1800s as a way of enabling blind and visually impaired people to read. It is a script in which any language can be translated into a tactile form, and it is used globally as a means for literacy for visually impaired people. Yet there are many limitations with Braille. Although Braille books exist, they are heavy, cumbersome, and the logistics of getting them to people is not always easy. There is also a limit to the information that has and can been translated into Braille.
As such, there is a growing need for refreshable displays. These are displays where people can feel Braille as well as tactile graphics – which could be graphs, scientific and mathematical concepts – that refresh so new information can be displayed. Refreshable displays would enable a large amount of information to be relayed from a single device. There are some companies that have been creating refreshable displays, but at very high costs of more than £10,000 per device. At such prices, these devices are not accessible to the majority of the global population who could make use of this technology. In order to meet the needs of blind and visually impaired people, refreshable displays need to be designed in a way that means they are affordable and accessible.
Designing an accessible alternative
In response to this, Tigmanshu Bhatnagar developed a new approach to tactile displays, which responded directly to the needs of users.
“The idea of this piece of research is to address one of the most pressing challenges of tactile access faced by visually impaired people today, there is very limited content available in Braille. Some of that content is not also available in local languages. People have limited access, which limits literacy levels among visually impaired people. It makes people more dependent on audio, but graphs, maps, spelling, grammar and punctuation cannot easily be relayed or taught through audio. That’s why I believe an affordable refreshable display is part of the future of education.”
Before deciding on this as being the focus of his research, Bhatnagar visited schools for the visually impaired, and spoke to teachers and students to understand the key challenges in terms of tactile access. He was keen not to design a solution before fully understanding the issues, and he wanted visually impaired people to provide him with full feedback about some of his ideas in order to design something functional and usable that would solve a problem. "There were many ideas that were technically easy to create, but users did not like them for various reasons," Bhatnagar said. "I kept re-making design decisions based on the needs of the people until I found something that made sense from all perspectives.”
The device Bhatnagar developed is called Tacilia, which is a tactile actuator using a sheet of Nitinol. This is a material known for its shape memory effect, meaning it can be bent out of place when heated, but it can be easily pushed back into place when it cools. Micro-heaters sit below the small Nitinol pins, which can create very targeted heat spots to make the pins rise up in specific places. These rising pins can create Braille text and graphic displays. The pins can be pushed down again so that new Braille text and graphics can be displayed.
Tacilia requires very few components, and the components it does need are inexpensive. This means that the size of the display could be increased, and the concept as a whole could be scaled up, while keeping it affordable for users.
Bhatnagar is keen to explore the commercial options for Tacilia. He was awarded a grant from UCL Business to continue working on a prototype and commercialisation options. He also went to the London School of Business to take part in some sessions with MBA students to understand how the product could be commercialised. In addition, Bhatnagar was awarded a grant from UCL and the Indian Institute of Technology Delhi (IIT Delhi) in India to develop a drawing interface on the device. Feedback from blind and visually impaired students shows that they want to be able to draw, so Bhatnagar developed a pen that blows out hot air, which pulls up the pins on the display to create shapes.
Bhatnagar would also like to gain more funding to hire engineers to work on the project. There are still some challenges to overcome, such as how to increase the size of the display, and how the device could interface with existing technologies. In the future, he would like Tacilia to connect to smartphones, tablets and computers so it becomes a plug and play monitor.
Prior to embarking on his PhD with UCL at the GDI Hub, Bhatnagar was working in industrial design for disabled people in India. He helped to make a stand assistive chair for a person with cerebral palsy who could not previously stand up unaided. He also developed a new motorcycle for a wheelchair-user, so they could go out independently and travel to work. “I started to understand that this field is not really about fixing a person,” Bhatnagar explained. “In India I was working with people who were just like everyone else, they just needed one problem to be solved. That led me to this PhD in assistive technology, because better design can improve life for many people.”
Funded by: UCL Overseas Research Scholarship, UCL Graduate Research Scholarship, UCL Business, UCL-IITD Strategic University Partners Seed Fund.
Tacilia logo below: