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.

Student and hacker [prusteen] recently fell in love with the Pomodoro method of time management. That’s where you concentrate on your task for 25 minutes, then take a five-minute break, and repeat this four times with a longer break at the end. Initially, [prusteen] was keeping track on their phone, but hated having to change the timer value between Pomodoros and break times. In order to keep the flow mode engaged, [prusteen] came up with this darling little study buddy that does it all with the push of a button.

By default, this tomato shows the current time, which we think is a handy and often-overlooked feature of Pomodoro timer builds. Press that momentary switch on the front, and it starts counting upward to 25 minutes. Then it beeps in stereo through a pair of buzzers when the time is up, and automatically starts a five-minute break timer. Press it again and the display goes back to clock mode, although judging by the code, doing this will cancel the timer.

Inside the juicy enclosure is an Arduino Nano, an RTC, and a 7-segment display. We love the attention to detail here, from the little green leaves on top to the anatomically-correct dimple on the underside. And we always like to see lids that snap on with magnets. So satisfying. Check out the brief demo after the break, which unfortunately does not include any lid-snapping action.

Do you need more interaction with your Pomodoro timer? Build yourself a pomo-dachi instead.

Seven-segment displays have been around for ages, and they have a really cool retro aesthetic about them. Over on Instructables, user alstroemeria (known as Jacky Mok in real life) decided to build a different kind of display that utilizes individual servo motors to slide the segments out, thus creating a 3D clock. The main board in this project was the Arduino Mega, which was selected due to its large number of digital GPIO pins that can set all 28 of the servos to the correct positions. 

The current time was tracked using the DS3231 RTC module that stores the time and can keep it even if power is removed. The program Mok wrote first initializes the servos and sets them in the “off” position. Within the main loop, the time is retrieved from the RTC module and converted into digits. From here each digit is mapped to a series of segments which are then moved into the correct spot with the corresponding motor. 

The clock enclosure Mok designed is quite elegant and captures the feeling of a classic seven-segment display. As seen in the accompanying video, watching the digits slowly move and morph into various shapes can be mesmerizing. More details on the concept and its construction can be found on Instructables. 

The post Kinetic digital clock takes 7-segment displays to another dimension appeared first on Arduino Blog.

Farkle is a classic dice game that only requires 6 dice and a way to write down scores based on the numbers rolled. Even so, this type of game isn’t inherently portable — it would be fairly difficult to play on a road trip, for instance. [Sunyecz22] decided that Farkle would make an excellent electronic game and got to work designing his first PCB.

This little game has everything you could want from a splash screen introduction to a handy scoring guide on the silkscreen. After choosing the number of players, the first player rolls using the momentary button and the electronic dice light up to indicate what was rolled. As long as the player rolled at least one scoring die, they can take the points by selecting the appropriate die/dice with the capsense pads, and either pass or keep going. The current player’s score is shown on the 7-segment, and the totals for each player are on the OLED screen at the bottom.

The brains of the operation is an Arduino Pro Mini. It controls two MAX7219s that drive the 42 LEDs plus the 7-segment display. A game like this is all in the code, and lucky for us, [Sunyecz22] made it available. We love how gorgeous the glossy 3D printed enclosure looks — between the glossy finish and the curved back, it looks very comfortable to hold. In the future, [Sunyecz22] plans to make a one player versus the computer mode. Check out the demo and walk-through video after the break.

The capsense modules are a great touch, but some people want a little more tactility in their handheld games. We say bring on the toggle switches.

When you think of a “7-segment” display, your mind naturally goes to something involving LCD or LED technology. As seen here, however, this 0-9 pattern can also be duplicated mechanically using a series of electromagnets.

Neeraj Rane’s 3D-printed device is controlled by an Arduino Nano, along with a shift register. These activate seven hand-wound coils that push the magnet-embedded segments in and out, via a series of IRF540N MOSFETs.

As of now, the display simply cycles through numbers. If a few more digits were added, and perhaps a user interface and/or an RTC module, it could form the basis of an even more interesting project. Check it out in action below!

Seven-segment displays are normally diminutive items, able to show info from a clock or other device, in a size that’s easily tucked away when not needed. Jegatheesan Soundarapandian’s single-digit display, however, is just the opposite standing at nearly seven feet tall.

The project is constructed out of cardboard, with a PVC spine for extra strength. Inside, addressable LED lighting illuminates each segment under Arduino control, with an HC-05 module used to interface with an Android app. Two 18550 batteries provide power for the unit, along with a DC-DC voltage regulator to supply the strip with 5V.

You can see it demonstrated in the clips below!

Deep freezers are a great thing to have, especially when the world gets apocalyptic. Of course, freezers are only good when they’re operating properly. And since they’re usually chillin’ out of sight and full of precious goods, keeping an eye on them is important.

When [Adam] started looking at commercial freezer alarms, he found that most of them are a joke. A bunch are battery-powered, and many people complain that they’re too quiet to do any good. And you’d best hope that the freezer fails while you’re home and awake, because they just stop sounding the alarm after a certain amount of time, probably to save battery.

If you want something done right, you have to do it yourself. [Adam]’s homemade freezer failure alarm is a cheap and open solution that ticks all the boxen. It runs on mains power and uses a 100dB piezo buzzer for ear-splitting effectiveness to alert [Adam] whenever the freezer is at 32°F/0°C or above.

If the Arduino loses sight of the DHT22 temperature sensor inside the freezer, then the alarm sounds continuously. And if [Adam] is ever curious about the temperature in the freezer, it’s right there on the 7-segment. Pretty elegant if you ask us. We’ve got the demo video thawing after the break, but you might wanna turn your sound down a lot.

You could assume that the freezer is freezing as long as it has power. In that case, just use a 555.

Good clocks are generally those that keep time well. But we think the mark of a great clock is one that can lure the observer into watching time pass. It doesn’t really matter how technical a timepiece is — watching sand shimmy through an hourglass has its merits, too. But just when we were sure that there was nothing new to be done in the realm of 7-segment clocks, [thediylife] said ‘hold my beer’ and produced this beauty.

A total of 28 servos are used to independently control four displays’ worth of 3D-printed segments. The servos pivot each segment back and forth 90° between two points: upward and flat-faced to display the time when called upon, and then down on its side to rest while its not needed.

Circuit-wise, the clock’s not all that complicated, though it certainly looks like a time-consuming build. The servos are controlled by an Arduino through a pair of 16-channel servo drivers, divided up by HH and MM segments. The Arduino fetches the time from a DS1302 RTC module and splits the result up into four-digit time. Code-wise, each digit gets its own array, which stores the active and inactive positions for each servo. Demo and full explanation of the build and code are waiting after the break.

When it comes to 7-segment displays, we say the more the merrier. Here’s a clock that uses pretty much all of them.

Flip displays are an interesting piece of technology, physically moving segments into place that stay put until other information is needed. Michael Klements has been especially fascinated by these devices, and after inspiration from another project, he decided to craft his own.

His version utilizes 14 micro servos to flip segments into a visible position, then rotate them to 90° when no longer needed. This “off” mode displays a slimmer profile, and the sides and back are painted black, making them much less visible.

An Arduino Mega, with 15 possible PWM outputs, is used to control the servos, while a hobby RC-style battery eliminator circuit provides power to the motors. 

Be sure to check out the build process and in-action shots below! 

Alarm clocks of old—and certainly many of those today—require several button pushes to set things up properly. Maker Michael Wessel, however, decided to implement his own take on a more intuitive clock, creating a device that features three separate eight-digit seven-segment LED panels. Eight buttons allow for direct manipulation of each of the digits, with their own dedicated LEDs.

The info on display includes time and date, as well as temperature, and it can even show how many days, hours, or minutes have passed since a special pre-programmed day. Up to seven audible alarms are available, which can be silenced by a loud noise (e.g. clapping your hands) via a sound sensor. 

The clock is controlled via an Arduino Mega, along with an RTC module to keep things accurate.

I remember I always had to set all digital clocks for my grandparents in the ’80s — these clocks and watches always required some complicated button juggling! So, here it is: a DIY LED alarm clock that my grandparents would have been able to set and use without my help! 

An Arduino-based LED clock with 7 individual alarms, highly intuitive user interface, temperature display, and display of days / hours / minutes passed since a special date, e.g., your birthday. An active / ringing alarm can be disabled by making a loud noise, e.g., by clapping your hands. Timer-based PWM sound output for alarm melodies. 

The Arduino’s EEPROM is being used to store the alarms of course, and the DS3231 RTC is battery backed up, so it survives a temporary power outage and you won’t be late for work the next morning. 

This was put together rather quickly, thanks to off the shelf components, Velcro and existing Arduino libraries for them! The clock can be built for about $30 – 40.