euclid The Time Traveler's Clock, User Manual

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even just their mechanical chronometer. The TTC has you covered for any imaginable
eventuality. (And, if you’ve spent a lot of money on your yacht or aircraft, you’d
certainly want to have the absolute, ultimate, most-reliable timekeeper available.)
History of Prototypes
Cesium Breadboard Prototype
The first experimental design was constructed with a Hamilton 21 chronometer, a
Microchip/Jackson Labs cesium chip-scale atomic clock (CSAC) (later used in the MCB
Prototype), a ublox GPS evaluation kit (EVK-M8T), a Maxim DS3231 real-time clock (RTC)
chip, and a servo mechanism to rotate the chronometer by a small amount (about one
half degree of arc) following the seconds pulses from the GPS and CSAC.
This prototype was used to determine if it was possible to resonate a mechanical
chronometer, how much motion would be required, and to refine the displays for time
from the GPS and the RTC. A circuit was incorporated to allow re-setting the RTC from
the GPS whenever desired.
Additional problems to be worked out were an automatic winding system, a backup
battery array, and the rotational suspension system for the Hamilton chronometer. The
circuits were constructed using multiple Arduino Nano microcontrollers, breakout
boards, and solderless breadboards. The gimbals of the Hamilton chronometer were
mounted to a cradle mounted on a large, thin ball bearing and rotated using a high-
torque digital servo motor. Solutions to most of these problems were worked out,
though reliability problems persisted with power supplies and the winding system. In
addition, the full-circle ball bearing prevented the chronometer being rotated upward
for convenient manual winding.
Figure 4: Cesium Time Traveler’s Clock Breadboard
Winding Mechanism
The mechanism which continually winds the chronometer required considerable
development. Winding the chronometer requires substantial torque. The state of wind