Tag Archives: Mega

Gorgeous Nixie clock features three types of tubes

via Arduino Blog

Nixie tubes require electricity in the range of 180VDC, making them challenging to work with. Maker Christine Thompson, however, decided to take Nixie art to a new level, creating a clock with three different types of tubes! 

This clock, or perhaps more accurately “info display,” shows the time and date with six IN-18 tubes mounted on the top. In the front, six IN-12A and two IN-15A tubes are also available to show time, date, pressure, temperature, and humidity.

A pair of Arduino Mega boards are used to control this retro-inspired contraption, along with an array of wiring, perf board, and other components, stuffed inside a very nice wooden enclosure. 

This is my first Nixie styled clock I have constructed. The clock actually consists of two clocks, the first being a 6 x IN-18 tube clock which is mounted on the clock’s top and displays both time and date. The second clock, this time based on 6 x IN-12A and 2 x IN-15A nixie tubes displays at the front of the clock and can display, time, date, pressure (with units and trend), temperature (both Centigrade and Fahrenheit) and, humidity (with units and trend). The time and date are separated with two single neon lamp-based separators, while only one of these lamps is displayed, to represent a decimal point, when the pressure, humidity or temperature is displayed. Both these clocks use “Direct/Static Drive” to power the displays and are based on two Arduino Mega 2560 boards. The fourteen tubes are driven by 12V to 170V DC to DC boost power supplies and 14 x K155 IC chips. The clock also powers two sets of Neon Lamps which switch off while the clock goes through its cathode cleaning cycle which happens at 19, 39 and 55 minutes past each hour. This cathode cleaning cycle consists of all six tubes displaying the digits 0 through 9 in sequence 6 times.

In addition the clock will sound a chime at 15, 30, 45 and 60 minutes. At the 60 minute chime the hour chime is also sounded. The chimes are standard MP3 files using a simple MP3 player controlled by the Arduino mega. In order to save on tube life all tubes are switched off automatically when the light level in the room dims to a predefined level, this is achieved using a LRD resistor located at the back of the clock. To help dissipate any heat build up both Arduino Mega ICs have copper heat fins attached and a 5V fan draws air out of the clock, cool air entering through a hole in the bottom plate.

The user can adjust the time, date, chimes, and chimes volume using one of two 16×2 LCD displays, located at the back of the clock. The BME280 temperature, humidity, and pressure sensor is mounted on the back of the clock so as to not be affected by the clock’s internal temperature.

A demo is seen in the video below, while more info and Arduino code can be found in the project’s write-up.

Q-Bot is an Arduino Mega-driven Rubik’s Cube solver

via Arduino Blog

Rubik’s Cubes seem to have been most popular in the 1980s, but never really went away. As such, if you have one lying around your house unsolved, why not ‘simply’ construct a machine to do this for you? 

One possibility is the Q-Bot, outlined here. While it won’t break any world records, it’s a solid-looking assembly that appears to be relatively easy to build.

The Q-Bot features six NEMA 17 stepper motors, four of which turn one face at a time. When needed, the other two use timing belts to alternatively pull opposed stepper motor pairs back, allowing the other two to rotate the entire assembly. An Arduino Mega is utilized to control the steppers via a custom shield, with a computer running the Kociemba’s Algorithm.

3D-printed “orbament” lights up with movement

via Arduino Blog

What would you get if you crossed a gigantic Christmas tree ornament with an LED strip and Arduino/IMU control? Perhaps you’d come up with something akin to this colorful “RGB LED Ball” by James Bruton.

The device features eight curved supports along with a central hub assembly, forming a structure for APA102 RGB LED strips. Each of these is linked together via wiring that winds through the central hub making them appear to the Arduino Mega controller as one continuous chain of lights. 

Several animations can be selected with a pair of control buttons, and the ball even responds to movement using an MPU6050 IMU onboard. Files for the build are available on GitHub.

Build an Arduino Mega fingerprint door lock

via Arduino Blog

If you don’t want to carry keycard or memorize a passcode, this build from Electronoobs might be just the thing. 

The system uses a fingerprint reader to check to see if you have access, and if approved, the device’s Arduino Mega unlocks the theoretical door using a micro servo motor. Three push buttons and a 16×2 LCD screen complete the user interface, and allow more authorized fingers to be added with the main person/finger’s permission.

While you might question the security gained by a hobby servo, the video notes that this could trigger any sort of security device, perhaps via a relay or electromagnetic coil lock. Besides security, the build gives a good introduction to Arduino fingerprint scanning, as well as the use of an SD card for data logging functions.

Sip and puff Morse code entry with Arduino

via Arduino Blog

Those that need a text entry method other than a traditional keyboard and mouse often use a method where a character is selected, then input using a sip or puff of air from the user’s mouth. Naturally this is less than ideal, and one alternative interface shown here is to instead use sip/puff air currents to indicate the dots and dashes of Morse code.

The system—which can be seen in action in the video below—uses a modified film container, along with a pair of infrared emitters and detectors to sense air movement. The device was prototyped on an Arduino Mega, and its creators hope to eventually use a Leonardo for direct computer input. 

A tube connected to a custom made bipolar pressure switch drives an Arduino which translates puffing and sucking into Morse code and then into text.

Puffs make repeating short pulses (dots) and sucks repeating longer pulses (dashes) just like ham radio amateurs do with a dual-lever paddle.

Code for this open source project can be found on GitHub.

Electric-powered fan rocket takes off and lands(?) vertically

via Arduino Blog

Does a rocket need to use a certain type of fuel, or even be capable of spaceflight? While James Bruton’s build might not fit everyone’s definition of this type of craft because of its electric ducted fan (EDF) propulsion, it does face the same major challenge of controlling a tall pipe-like structure from thrust coming from the tail. It’s meant to both take off and land in a vertical orientation as well, something inconceivable in traditional rockets until very recently.

For control, Bruton uses an Arduino Mega inside the main fuselage of the craft, which regulates the speed of the three EDFs. It also turns two of these fans with a servo and linkage system in order to compensate for unwanted roll. A second Arduino and an IMU are embedded in the nose cone, which passes data to the Mega board via a serial connection. 

The build and early tests can be seen in the video below, and a full test is planned for the future alongside Ivan Miranda, who has been working on his own version.