Planet Arduino

It is amazing how much technological progress humanity has achieved over the past few centuries. But while our capability with electronics has shot ahead, it seems that we’ve almost regressed when it comes to mechanical and electromechanical design. Watches and clocks are great examples of this, as pre-digital craftsmen were capable of astonishing feats that are still impressive today. But some people are keeping those traditions alive, as evidenced by this mechanical seven-segment display clock driven by a single stepper motor.

This clock is truly a work of art. It shows the time across six digits, each of which is a seven-segment display. But those aren’t segments lit by LEDs, they’re physical pieces of plastic. A complex series of gears flips them in and out in the appropriate sequence to display the numeric characters. That is very impressive when you consider that the segments don’t actuate in an order that correlates with the numerical value — the number 4 isn’t simply turning “on” one more segment than the number 3. But even so, the clock progresses through the numbers in order.

That’s only possible because of the genius mechanical design of the clock. Further increasing the wonder is the fact that the clock and all of its parts were 3D-printed — no precision machining necessary. An Arduino Nano board controls the stepper motor that drives the whole series of gears. That ensures that the motor turns at a constant rate, which is required to keep accurate time.

The post A single stepper motor drives this mechanical seven-segment display clock appeared first on Arduino Blog.

There’s certainly no shortage of DIY clocks in the Arduino community; however, Eric Nguyen has come up with a rather unique way of showing hours and minutes: steel balls arranged as seven-segment displays.

For each time change, the face rotates down and a tray of arranged balls is lifted up to meet it via a servo motor assembly. Inside, a series of 28 servos capture and release the balls using magnet and linkage systems, plus another for the colon.

The device is powered by a Nano along with an RTC module for accurate timekeeping, and two PCA9685 driver boards control the motors directly.

As illustrated in the videos below, it’s an incredible build from a mechanical standpoint. Making it even more impressive, this is actually Nguyen’s first Arduino project!

Clocks normally tell you the time in your particular location, but what about that person that you know across the country or even on the other side the world? What time is it there? While it’s easy enough to do a web search or do a calculation, in order to find this out at an instant, Jeremy Cook made his own mechanical dual time zone clock.

The device is powered by an Arduino Nano, which drives a stepper motor to advance each minute. Using physical gear reduction, dual hour gears move at 1/12th the rate of the minute indicator gear, which can be offset to the secondary time zone of your choosing.

A real-time clock module is implemented to time each stepper advance, and a single button fast forwards the assembly when needed. Code, while still in a somewhat experimental state, is available on GitHub.

Magnets are amazing devices, and thanks to this project by “tomatoskins,” they can even be used to mysteriously tell time. His project uses magnets hidden behind a classic walnut veneer to rotate a pair of ball bearings around the unique clock face.

While externally minimal, there’s a lot going on inside its wood surface. The clock is controlled by an Arduino Nano along with an RTC module for accurate timekeeping. A 28BYJ-48 stepper motor-driven, 3D-printed gear system guides magnet positions and Hall effect sensors are used for both the hour and minute hands. 

Arduino code as well as mechanical design files are available in tomatoskins’ write-up.

[wyojustin] was trying to think of projects he could do that would take advantage of some of the fabrication tech that’s become available to the average hobbyist. Even though he doesn’t have any particular interest in clocks, [wyojustin] discovered that he could learn a lot about the tools he has access to by building a clock.

[wyojustin] first made a clock based off of a design by [Brian Wagner] that we featured a while back. The clock uses an idler wheel to move the hour ring so it doesn’t need a separate hour hand. After he built his first design, [wyojustin] realized he could add a planetary gear that could move an hour hand as well. After a bit of trial and error with gear ratios, he landed on a design that worked.

The clock’s movement is a stepper motor that’s driven by an Arduino. Although [wyojustin] isn’t too happy with the appearance of his electronics, the drive setup seems to work pretty well. Check out [wyojustin]’s site to see the other clock builds he’s done (including a version with a second hand), and you can peruse all of his design files on GitHub.

Looking for more clock-building inspiration? Check out some other awesome clock builds we’ve featured before.