Last year, Swiss watchmaker Urwerk announced that it was working on a wristwatch containing the world's first mechanical movement with an electronic monitoring system. The fruits of its of labor are now on display in the Urwerk Electro Mechanical Control (EMC) watch, which uses advanced electronics to monitor the precision movement’s performance within 10 microseconds.
Theoretically, a wristwatch should work as well as the best ship’s chronometer, but riding on a wrist isn't the best place for accurate timekeeping. It’s bit like those thermometers found on some digital watches. They may be good thermometers, but the temperature they usually display is that of your wrist.
It’s the same with a wrist chronometer. Acceleration, changes in position, temperature, and pressure, all add up. You could eliminate all this by not wearing the watch and keeping it in a an air-tight case, but Urwerk points out that that defeats the purpose of a watch, so the next best thing is to find out how much the watch is straying from perfect time and compensate. And that is what the EMC does; monitor the movement's timing rate and tells you by how much to adjust it.
The key to this is the delta/δ indicator found on the EMC’s face among the circular and crescent subdials displaying hours, minutes, seconds and the power reserve indicator. The delta/δ indicator activates with one touch of a button and gives an instantaneous readout of the watch’s performance within a range of variation of up to minus 20 and plus 20 seconds per day. Using this information the wearer can then turn a screw on the reverse of the watch, so it runs neither too fast, nor too slow.
That simple looking indicator is backed by some sophisticated technology with a electronics board built into the movement. This uses an optical sensor to monitor the bespoke balance wheel and compares the balance wheel rate against a 16 million Hz reference oscillator. The difference is calculated in the watch and displayed on the delta/δ indicator, which is accurate to within 10 microseconds.
In a neat effort to keep batteries out of the argument, Urwerk has installed a supercapacitor charged by a micro-generator made by the Swiss company Maxon, which is powered by a handle built into the watch.
This is all tucking inside a DLC-treated titanium and steel case measuring 43 mm x 51 mm x 15.8 mm with a shot-blasted finish. There’s a sapphire crystal and the whole thing is water resistant to 30 m (100 ft, 3 ATM). Inside is the manually-wound UR-EMC calibre movement developed and manufactured by Urwerk, powered by vertically mounted double mainspring barrels, connected in series with a Swiss lever escapement and a bespoke balance wheel made of non-magnetic, anti-corrosive ARCAP P40 alloy coupled to the optical sensor.
“EMC is an ode to the mechanical watch and craft of the watchmaker,” says Felix Baumgartner, master watchmaker and co-founder of URWERK. “The mechanical watch is a sensitive organism and the timing rate of its movement can fluctuate due to several factors. These changes of pace and performance can easily be detected by a watchmaker, a professional who is armed with the equipment necessary for testing the accuracy of the movement. However, it is rare for an amateur to have these tools. But with the EMC, an amateur can have them and is able to dive into the heart of their watch, to see it live and evolve. And we even give the owner a chance to interact with it by allowing them to adjust its timing rate to better suit their daily rhythm and pace of life.”
The Urwerk EMC has a quoted retail price of $120,000 in North America and is a limited run of 55 examples.
The video below introduces the Urwerk EMC.