Vibrating Braille Display Is Portable

Smartphones are an integral part of life, but what if you can’t see the screen? There is text-to-speech available, but that’s not always handy and can be slow. It also doesn’t help users who can’t hear or see. Refreshable braille devices are also available, but they are expensive and not very convenient to use. [Bmajorspin] proposed a different method and built a prototype braille device that worked directly with a cell phone. The post admits that as the device stands today, it isn’t a practical alternative, but it does work and is ripe for future development to make it more practical.

The device saves costs and increases reliability by using six vibration motors to represent the six dots of a braille cell. However, this leads to an important issue. The motor can’t directly mount to the case because you have to feel each one vibrating individually. A spring mounting system ensures that each motor only vibrates the tactile actuator it is supposed to. However, the system isn’t perfect, and fast output is difficult to read due to the spread of vibrations.

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Metronome Flashes And Vibrates To The Beat

Annoying though they can be, if you play any kind of instrument, you will definitely benefit from using a metronome. While many of them thock or otherwise tock, the VRRVRR metronome from [Turi] works a little differently.

In addition to flashing LEDs, the VRRVRR contains a small vibrating motor. If you’re wondering about the name, it comes from the fact that it vibrates and makes a sort of vrr vrr sound. Need to be quiet? A small switch on the side shuts off the vibrations.

The 4×4 keypad really allowed [Turi] to cram in a bunch of features using both short and long press to do different things. On short press, the digits set the tempo. When not typing in a tempo, zero can be used to enter a tempo by tapping. The letters load preset tempos, and the +/- keys increase and decrease it.

Inside the basswood enclosure is a Raspberry Pi Pico, the vibration motor, and various other bits and bobs that make it go. There’s even an LED to indicate that it’s time to charge the lithium battery. If you want to build your own, head on over to GitHub, but be sure to take the brief VRRVRR tour after the break.

We don’t see too many metronomes around here, but we do have this nice teardown to offer you.

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Arduband Gives Your Eyes A Hand

Let’s face it, we probably all sit at our computers for way too long without getting up. Yes, there’s work to be done, games to be played, and the internet abounds with people who are wrong and must be down-voted and/or corrected. We totally get and respect all that. However, if you want to maintain your middle- and long-range vision, you should really get up regularly and gaze out the window for a bit.

In fact, the Arduband does you one better. Its Arduino Nano and accelerometer check your position every ten minutes. If you haven’t changed your Z by the third check, then it’s time for a break. The combination of an RGB LED, buzzer, and vibrating disc motor working together should be enough to pull you out of any computerized stupor, and they won’t give up and go back to sleep until you have stood up and remained upright for one minute.

We like that [ardutronics123] spun up a board and made it small enough to be wrist-mounted using a watch strap. It would work just as well worn around your neck, and would probably even fit in your pocket. Blink a few times before you check out the build video after the break.

Arduband would be great on the go, but who does that anymore? If you spend every day at the same desk, you could point a time-of-flight sensor at your chair and start a timer.

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This Vibrating Continuity Tester Is Quietly Useful

Continuity testing is one of the most valuable functions on the modern multimeter. It will help you investigate wiring problems in your car, tell you if you’re holding a nullmodem serial cable or the regular kind, and even reveal when you’ve accidentally shorted the data lines right to the power supply. However, all that beeping can get annoying, so [bitelxux] built a vibrating version instead.

The build was borne out of necessity; [bitelxux]’s meter lacked a buzzer, and it grew frustrating to always look at the display. In order to allow late night hacking sessions to go on undisturbed, an unobtrusive vibrating tester was desired, as opposed to the usual audible type. Two whiteboard markers donated their shells to the hack, fitted with small nails to act as probes. Inside, a pager vibration motor is connected, vibrating when continuity is found. The circuit runs from a 1.5V AA battery which neatly fits inside the marker shell.

It’s a basic build, but gets the job done with a minimum of fuss using parts that most makers probably have lying around. Of course, you can always go a slightly more complicated route and throw an Attiny at the problem.

Many Ways To Drive A Small Motor

Tiny motors used for haptic feedback and vibration come in a variety of shapes and sizes. The most familiar is the “eccentric rotating mass” (ERM) variety which just spins an imbalanced weight on a small motor and comes packaged in two form factors. The classic is the pager “pager motor” which just looks like a tiny, adorable motor and the squat cylindrical “pancake style”. ERMs are simple to use but provide imprecise response when compared to their new-age cousin the “linear resonant actuator”. Unlike the motor in an ERM, LRAs are typically an enclosed mass on a spring placed near a coil which pushes the mass back and forth. The name LRA might not be familiar but Apple’s branded implementation, the Taptic Engine, might be a little more recognisable.

[Precision Microdrives] is a vendor of these sorts of devices who happens to have a pleasantly approachable set of application notes covering any conceivable related topic. A great place to start is this primer on ways to drive motors with constant voltage in a battery powered environment. It starts with the most simple option (a voltage divider, duh) and works through a few other options through using an LDO or controller.

If you’re thinking about adding haptics to a project and are wondering what kind of actuator to use (see: the top of this post) AB-028 is a great resource. It has a thorough discussion on the different options available and considerations for mounting location, PCB attachment, drive modes, and more. Digging around their site yields some other interesting documents too like this one on mounting to fabric and other flexible surfaces. Or this one on choosing PWM frequencies.