We love looking at roll-your-own wristwatch projects. Getting a project small enough to carry around on your wrist is a real challenge. But we think the OTM-02 wristwatch really hit the form factor right on the mark.
OTM stands for Open source Time Machine. It’s the work of [Hairy Kiwi] and he managed to bring the guts of the watch in at a thickness between 6.5 and 7mm. That includes the LCD, PCB, piezo diaphragm, and the battery. The PCB itself is a four-layer board built on 1mm thick substrate. It’s running an EFM32 (ARM) microcontroller which comes with hardware USB support. The little door sitting open on the side of the 3D printed enclosure provides access to the micro USB connector which can be used to charge the 150 mAh battery inside. That may not sound like much juice, but if you set the display to show minutes only [Hairy] calculates a battery life approaching 175 days. If you just have to have the seconds displayed you can expect about two weeks between charges.
Like the name says, this project is Open Source.
There are 2 types of people in the world; those who know binary, those who don’t, and those who know ternary. [Emanuele] thought a binary wristwatch is the pinnacle of nerd and set out to build his own. The resulting binary clock not only screams nerd as intended, but is also a functional time piece, as well.
The idea of a binary wristwatch came to [Emanuele] while he was working with PICs at school. Not wanting to let that knowledge go to waste, he used a PIC16F628 microcontroller for this build. There are four LEDs for the hours and six LEDs for the minutes, each attached to a separate microcontroller pin for easy programming.
To keep time, [Emanuele] kept the PIC in sleep mode most of the time, only waking it up when a an internal timer’s register overflows. The watch spends most of its time sleeping, sipping power from a coin cell battery with a battery life that should last weeks, at least.
The entire circuit is tucked away in a PVC enclosure with a wonderful rainbow ribbon cable band. We’re not so sure about how that feels against the skin all day, but it does exude the nerd cred [Emanuele] was looking for.
This slmwtch lives up to its name. When the LCD screen is folded back onto the PCB the entire thing comes in at just 2.35mm. That’s including a coin-cell battery not shown above. Wow!
Part of what makes this possible is the specialized PCB design. [Anders] didn’t want to add more thickness than the screen and battery so he make a cutout in the PCB design to accept each component. In this image it’s easiest to see on the two SMD resistor in the upper left. They’re held in a void by the two solder connections. Admittedly this is not going to be a mass-production friendly design. And we have concerts about the long-term stability of suspending components by their leads. But as a one-off it’s fantastic! See for yourself in the video after the break.
The control for the watch uses two touch sensitive pads on the back of the PCB. There is no backlight for the display which can be a problem when trying to read the time while outdoors. We wonder if an ePaper display with similar dimensions is available?
Continue reading “Super slim wristwatch build”
Wow, we’re seeing all kinds of good stuff from NYC Resistor today. [Caleb] found this link to [Hudson’s] early work on a geeky wristwatch. It is based around an HDSP-2112 eight-digit alpha-numeric display. Each digit is a 5×7 array of LEDs, but the look of it really reminds us of [Woz’s] Nixie Wristwatch. The nice thing about using a display like this one is it’s much easier to drive and the power requirements don’t really call for special consideration either.
The display happens to be nearly the same footprint as the Teensy 2.0. In fact, the display is a bit longer. That makes it a perfect backpack, bringing everything necessary to drive the display. Check out the video after the break to see it scrolling the time as words, and displaying numbers.
This needs to have an RTC and portable power source before you can wear it around. But the proof is there. Perhaps [Hudson] will spin his own board with a uC that includes RTC capability and a charging circuit for a tiny Lithium cell.
Continue reading “The beginnings of a geeky wristwatch”
Whether inspired by the vaults of Fallout or the mysterious wrist device worn by [Turanga Leela], we’re just glad to see someone finally made a wrist-worn cellphone,
The Ultimate Wrist Watch, as the creator [Rob] calls it, is based on his Motorola Defy smart phone, tucked inside a neatly modified iPod wrist band meant to hold a runner’s music player. Simply mounting a cellphone to a wrist would be a bit awkward and a huge drain on battery life, so [Rob] wrote an app to automatically turn on the display when the accelerometer detects the phone is in the correct watch-reading position, and turns it off when [Rob] lowers his arm once again.
Right now the Ultimate Wrist Watch only stands in for the functions of a standard wrist watch – time, date, a chronometer and stopwatch are just about the only features implemented so far. Still, this is dangerously close to the wrist-mounted computers we’ve been promised for so long.
You can grab the source for the Ultimate Wrist Watch on [Rob]’s git, or just download it off Google Play. Check out the video of the Ultimate Wrist Watch after the break.
Continue reading “We’re *this* close to a real Pip-Boy”
[Bill] wants a little piece of mind when his infant is sleeping in the other room. For him, the audio-only baby monitor could use some improvement. His proof-of-concept is that blue patch Velcroed on the swaddled infant. It monitors movement, orientation, and temperature and alerts you when something’s amiss.
Inside the pouch you’ll find a TI Chronos eZ430 wristwatch with the band removed. It’s a nice hardware choice because it includes an accelerometer, temperature sensor, and RF link to a USB dongle. [Bill’s] code sends a data packet to the PC about once a second. The PC watches to make sure there’s slight motion, indicating the baby is breathing. This part doesn’t work all that well as the accelerometer doesn’t pick up tiny movements all too well, but it does have potential. In the video after the break you can see the functions which make sure the baby doesn’t roll onto its belly, and that she’s not too cold do work extremely well.
We wonder if the accelerometer would pick up more motion if the watch was hung from a string inside of a small enclosure. This way it would swing back and forth with small movements. But perhaps that would make the whole thing too bulky?
Continue reading “TI Chronos watch monitor your sleeping infant”
The [Fédération Internationale de Football Association] is joining the growing list of professional sports that is adopting technological means in an attempt to help the human referees. After a botched call in 2010 the organization called for a system that would work day or night, with 100% accuracy and the ability to report to the Refs in less than 1 second. The applicants have been weeded out and it comes down to two systems, both of which use a piece of personal hardware we’re quite familiar with. [Fe80], who sent in the tip, recognized the TI Chronos eZ430 watch in the image above.
The two systems both use the watch as an interface, but work very differently. The first, called GoalRef, uses a sensor suspended inside the ball. This detects a magnetic field made up by the goal posts. We’d guess it’s an inductance sensor that is triggered when it passes a coil in the goal posts (we didn’t find much in the way of technical info so please do your own speculation in the comments). The second system is very familiar. It’s the Hawkeye camera system used by the APT (Tennis) in all the major tournaments.