Tag Archives: uno

Geometric Nixie tube clock and environmental display

via Arduino Blog

Creators keep coming up with new clock designs, and while you might think that every new possibility has been exhausted, Christine Thompson has proved this assumption wrong once again with her “VFD Trilateral Clock.

This Arduino Uno-powered device employs a stepper motor to rotate a triangular prism shape with scales for hours and minutes on one side, temperature in Celsius and Fahrenheit on the other, and humidity and pressure on the third surface.

The geometric scale travels in 120-degree steps, causing each face to line up with a pair of IN-13 Nixie tubes on either side. These linear tubes are then used to indicate time and environmental conditions in a beautiful bell jar display, as seen at around 3:30 in the video below.

While waiting for the delivery of parts for another project I decided to push ahead with this project. At its heart is two IN-13M Nixie tubes. These tubes are designed to provide a linear scale between maximum and minimum points using an illuminated column. The project uses two of these IN-13M, three wire Nixie tubes to show, time (Hours and Minutes), temperature (Celsius and Fahrenheit), Humidity (percentage), and Pressure (millibars).

At this point I would like to thank Dr. Scott M. Baker for his great web site, which provided me with all the information I needed to get these Nixie tubes to work. In particular the Current Regulator as displayed and detailed on his web site.

The project uses a BME280 sensor to determine the temperature, pressure and humidity and RTC clock to monitor time. As the system needs to display six different values it was necessary to construct a rotating central display which showed these values against six scales. In order to achieve this an equilateral triangle of wood was fashioned, each side showing two sets of values. A stepper motor was mounted under the top platform and this motor rotates through 120 degrees in time for the next set of values to be displayed on the two Nixie tubes.

GymSoles ensure correct form and posture during your workout

via Arduino Blog

While you can get a very good workout on your own, it’s ideal if you have someone else watching over your form. This, of course, isn’t always practical, so researchers at the University of Auckland’s Augmented Human Lab have prototyped a wearable system called GymSoles to help. 

GymSoles consists of a pressure-sensitive insole that is used to determine a foot’s center of pressure, and thus infer whether or not the participant is keeping the weights in the proper position relative to his or her body—perfect for exercises like squats and deadlifts. 

Feedback is provided visually as well as through tactile feedback via eight vibrating motors, allowing participants to modify technique without having to focus on a screen. A computer is used to control the device using an Arduino Uno with motor drivers and an I2C multiplexer.

The correct execution of exercises, such as squats and dead-lifts, is essential to prevent various bodily injuries. Existing solutions either rely on expensive motion tracking or multiple Inertial Measurement Units (IMU) systems require an extensive set-up and individual calibration. This paper introduces a proof of concept, GymSoles, an insole prototype that provides feedback on the Centre of Pressure (CoP) at the feet to assist users with maintaining the correct body posture, while performing squats and dead-lifts. GymSoles was evaluated with 13 users in three conditions: 1) no feedback, 2) vibrotactile feedback, and 3) visual feedback. It has shown that solely providing feedback on the current CoP, results in a significantly improved body posture.

This compass reads the correct heading even when tilted

via Arduino Blog

Consider an analog or even digital compass. While you can reasonably expect either to point towards magnetic north when held flat, when you add tilt and/or roll to the equation, things get a bit wonky. That is unless you’re maker “lingib,” who was able to construct a magical compass using an Arduino Uno and an MPU-9250 IMU unit, with an accelerometer/gyro in the same package.

As seen in the video below, when the compass unit is set at an angle, the heading output varies significantly—as much as 100 degrees according to the project write-up. When stabilization is turned on, however, the gyro/accelerometer is used to compensate for magnetometer heading variations—reducing output errors to just a few degrees.

This Instructable explains how to make a tilt compensated compass using an Arduino Uno R3, an LCD display, and an IvenSense MPU-9250 multi-chip-module that contains an MPU-6050 accelerometer / gyro and an AK8963 magnetometer within the same package.

The LCD simultaneously displays the heading, (P)itch, and (R)oll.

The heading accuracy is within 2 degrees depending on how well the compass has been calibrated.

Without tilt compensation the compass headings vary significantly … sometimes by as much as 100 degrees.

When stabilised, the tilted compass headings only vary by one or two degrees … the improvement is amazing.

The tilt stabilization may be disabled by placing a jumper wire between Arduino pins A0 and GND.

Modular CNC machine made with Arduino

via Arduino Blog

Arduino boards running GRBL software have long been used for CNC machine control, but usually you need to choose between having a router or laser cutter. This project, however, is specifically designed to accommodate both with a modular carriage system.

Build-wise, it’s a fairly standard XYZ gantry CNC — with a frame made out of V-slot aluminum extrusions from OpenBuilds cut to length by a circular saw. The X and Y axes are controlled via NEMA 17 stepper motor and belt drive assemblies, while height adjustment is accomplished with a NEMA 23 motor and screw drive.

The electronics are all hidden away in a separate enclosure, including the Arduino Uno/CNC shield that serves as the brains of the operation and a cooling fan to keep the temperature inside in check. 

If you’ve been considering doing this type of build, this looks like a great place to start, and you can see a demos of it in laser and spindle modes in the videos below.

Notable Board Books are an Arduino-powered way to enjoy music

via Arduino Blog

Annelle Rigsby found that her mother, who suffers from Alzheimer’s, is delighted to hear familiar songs. While Annelle can’t always be there to help her enjoy music, she and her husband Mike came up with what they call the Notable Board Book that automatically plays tunes.

The book itself is well laid-out, with song text and familiar photos printed on the pages. Electronics for the book are in a prototype state using an Arduino Uno and an Adafruit Sound Board to store and replay the audio bits.

Page detection is handled by an array of photocells, and it is meant to turn on automatically when picked up via a series of tilt switches. When a switch is triggered, a relay can then hold the book on until the song that is playing is done, or for a predetermined amount of time.

Ingenious marble clock runs on Arduino

via Arduino Blog

Arduino boards and custom clock builds seem to be a great match, as illustrated by Görkem Bozkurt’s recent project. 

His 3D-printed marble clock uses a stepper-driven gear mechanism to lift 11mm steel spheres to the device’s top chute. The spheres then roll down to a five-minute rail, which empties when filled and transfers a single marble to another minute rail, graduated in five-minute increments up to 60. This then fills the hour rail in a similar process, letting you tell the time of day, or simply be mesmerized by its movement.

The main gear mechanism is powered by a small stepper motor, controlled by an Arduino Uno for timekeeping.

If you’d like to build your own, code is available on Bozkurt’s write-up, as well as the needed print files.