This project was done as a part of Product Design Lab-II course at Engineering design department- IIT Madras. The course aims to have group of 4-5 students get together and build a working prototype of a product- starting from Ideation, market analysis, to product development.
I, along with 4 other students from the department, embarked on making an ambitious project- making a “Refreshable” Braille display.
Braille is the standard script for blind people, and there have been numerous publications in the language. But, with the advent of “e-book readers”, it is imperative there are facilities which would function as such readers in Braille. We performed a market research, and realised such readers exist in the market, and they are not affordable by people in a country like India.
Seeing this, we also found out majority of systems use Solenoid-pin actuation mechanism for moving the tactile pins in the Braille cell. Now, the micro-solenoid system is expensive, and primarily due to the heat generated by the system. In such a case, we were looking at inexpensive methods of actuating the same.
I was browsing through, and talking to a couple of professors, when we came across materials called Shape memory alloys. It works as given below:
I proposed the idea of looking at Shape memory alloys as actuation mechanism. It is a state-of-art technology, and a pain to obtain in India, but thankfully, studying at IIT enabled us to obtain good enough amounts of the material for testing, and prototyping.
Our professor however wasn’t convinced. Hence, we designed it in CAD, and performed a mathematical study, with some experiments with regards to the heat generated by the system. We found out the model would be feasible, and went ahead with the work. Personally, I was leading the team, managing budget and inventory, doing the electronics design/fabrication, and performing the Shape memory alloy fabrication in the required shape. We split up the work into parts, with some people focused on CAD and the 3-D printing (this was fun though!), some of us working on the electronics, and all of us working on the prototype. And finally, we got a working prototype of the Braille display. The preliminary CAD model we had was something like this:
Our final product can actuate a single-braille charachter, albeit with one basic problem: Lack of modularity.. We couldn’t find time to fix up the modularity issue, and hence it persists in our final model too.
We are greatly thankful to the Central workshop at IIT Madras, Center for Innovation- where we got place, and all the tools required for fabrication from 3D printers to soldering rods and Prof. Sivakumar (Applied mechanics) and Prof. Vedantam (Engineering Design) who encouraged us with the SMA idea, and provided the same!
And a huge shout out to my friends (classmates!) from ED- Moon, Tanay, Vaibhav and Theo- for being such a wonderful team and putting a good fight on the project!