Adding an Opto-Interruptor Part 3   As I’ve already discussed here and here, opto detectors are one way to sense position. Unlike a switch, there’s no moving parts, so reliability is high. However, the compromise is a more complicated setup. In a previous article, I showed a schematic that sent a signal to the Arduino when the light beam was unbroken between diode and sensor, and turned off when it was broken. One reader commented that the usual way was the reverse, and included a link … Continue reading →

The Braille Display Movable Head   For Phase 2, I decided to change some of the details for the device. In particular, I didn’t like the flexibility of the Acrylic pieces, and needed something more solid – solid means faster motion, which means speed in updating. My solution was to create the head out of plates of acrylic, which are then bolted together. The result is much stiffer, much stronger, and therefore faster moving: Another change is the use of linear bearings for the motion (orange … Continue reading →

Audrey Pankhurst, 1927-2008   Today marks the fourth anniversary of my mother passing. I find there isn’t much I can (or wish to) say here about my mother. She taught me to strive to be good, no matter what others try and do. She was a voracious reader (part of the reason I felt she should be the namesake of the Braille Reader/Refreshable Display). She was a kind person, and she is missed. Here’s a picture of her, taken about four years before the … Continue reading →

ASC VI and Makerspace Moving   Monday Feb 6 was the next ASC (#6), and the event was over the top in a number of ways. Previously, the highest level of grant was $500-$600 (with an upper limit of $1,000 if enough judges participated); this time extra funds from corporate groups raised it to $3,500. As well, the judging was two-phased; the initial ten (of which eight actually appeared) were winnowed down to a top three on Monday, and on Thursday the final three make a … Continue reading →

Mounting Motors – a Plastic Solution In Sketchup   For my next Braille device design, I wanted to mount the main drive motor simply. In the previous design I used several pieces to let it move up, down, and forward/backwards. A lot of pieces, and a pain to keep together in a tight space. So this time I wanted simple. The result is a glued acrylic box that supports the motor, yet allows 2 dimensional movement, as well as fine tuning of the motor in its mount: Basically, you … Continue reading →

How The Braille Machine REALLY Works   I’ve discussed the Braille device in detail, but until now there’s been no running examples – so I thought I’d upload a video of it in action. The video shows the stepper motor in action, and how the gears move from Braille rod to rod (removed to show the gears underneath). One thing you might notice right away – the speed. Working with Acrylic, while visually pretty, is not good for fast movement as it flexes too much. Also, since … Continue reading →