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.
This wristwatch is hiding a lot of features in its hardware and its software. It’s called the TicTocTrac and it’s a Senior project for a pair of students at Cornell University. Judging from the sheer volume and quality of the project documentation we wonder if someone has a science writing career ahead of them? Be we digress… It’s a clock and we love it!
First off, this does more than just tell the time. In fact, that’s almost an ancillary function in this case. The wristwatch is more of a metering device to record your own time-based behaviors. Find yourself checking your watch frequently as the lunch break approaches? This watch records that activity and you can later graph the data. This allows you to analyze how you percieve the passage of time. The more often you check the time, the slower you feel time progressing. The documentation does a much better job of describing this than we have time for, so check it out.
On the hardware side of things we’re quite impressed. The housing is 3D printed. It hides two half-circle PCBs below the full-circle PCB face plate. The half-boards leave space for a tiny rechargeable battery, and host a vibrating motor and RTC chip. Instead of using buttons, there’s a piezo sensor which detects when you tap on the top of the watch.
[Nav] is working on a scratch-built wristwatch. Although it is based on an MSP430 microcontroller, it’s not the ready-to-hack ezCronos that you might be thinking of. Instead, [Nav] started with a different TI development tool that we’ve looked at before, the ez430-F2013.
The breakout board for the F2013 is small enough to meet his needs, but still provides easy soldering with 0.1″ vias that break out each pin. To make sure the timepiece is accurate he added a 32.768 kHz clock crystal. A small, square, LCD screen acts as the face of the watch, but we didn’t find specific part information for the display.
Currently the watch can run for a few days on the CR2032. We’d bet some work with sleep modes for the microcontroller can help with that. The watch has a couple of buttons that let you control it, and [Nav] discovered that he could fit everything into the watch case for an iPod nano. That’s creative!
We’ve seen other hacks with tiny batteries. The next logical step here would be to swap out the disposable coin cell for something that can be topped off with an external charger.
We hate to admit it, but we missed out on the TI Chronos watch deal last week. While we’re still a little bit burned over the fact that these watches sold out so fast, [Ahmet] sent in his Open Source Bluetooth Watch and we’re thinking this could eventually be a decent replacement.
The watch is built around an Arduino Pro Mini, a scavenged Nokia LCD, and a BlueSMiRF Gold. The Bluetooth connects to a Nokia N900 with a little Bluetooth client app [Ahmet] wrote. He also wrote a small GUI for the watch’s LCD display. Afterwards, he was able to display missed calls, new email, and is now working on support for changing songs on his N900’s media player.
Admittedly, a little work needs to be done on the enclosure. Still, the potential for this watch is much greater than the iPod as a watch project we saw last year. Right now, we’re thinking about what could be added to [Ahmet]’s watch. An accelerometer would probably be on the top of our list, but if you have any ideas feel free to leave them in the comments.
Check out the walk through of the watch’s functions after the break.
Continue reading “Bluetooth wristwatch based on an Arduino”
This bulky package is a Nixie tube wristwatch. We still like [Woz’s] watch better but this one has a few nice tricks of its own. Notably, there aren’t any buttons to set the time. Instead, a large magnet is used to actuate a magnetic switch inside the body. Speaking of enclosures, the case is aluminum and the face plate is polycarbonate but looks like it’s been vacuum formed. Check out the clip after the break.
Continue reading “Use a big magnet to set the time”
This wristwatch circuit board has some pretty interesting digits. They’re older components that give a classic look to your wristwatch display. On board you’ll find a PIC 16F628A running with an external clock crystal. The display isn’t always illuminated (kind of like Woz’s watch) in order to save the batteries, but can be woken up for a short time with the push of a button. The steam-punk-ish body seen to the left is the just first try. This guy has four more boards left so it should be fun to see what he comes up with.
[Via Hackaday Flickr Pool]
[Ziyan] and [Zach] built a door entry system that uses a code entered from your wristwatch. They’re using the TI eZ-430 Chronos that we saw in November. There is a project box mounted over the deadbolt lever. Inside, the wireless fob waits for the watch to connect. When a watch has connected and the correct code is received (using 128 bit encryption) the fob actuates a servo to turn the lock. On the user side of things the code is entered by tapping the watch. The built-in accelerometer picks up these taps and relays them to the door unit.
It’s a heck of a project! Check out their demonstration video after the break. We’d like to see a mechanical option for escaping the apartment in case the door unit fails but otherwise we think this is perfectly executed. We’re looking forward to seeing more projects that tap into this TI hardware.
Continue reading “Coded entry using your wristwatch”