Arduino Hacks

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IP Tracker

An Arduino Device That Monitors Your External IP Address

March 6, 2015 by 43 Comments

[Bayres’] dad setup a webcam as a surveillance camera for a remote property. The only problem was that the only stable Internet connection they could get at this property was DSL. This meant that the external IP address of the webcam would change somewhat often; the needed a way to keep track of the external IP address whenever it changed. That’s when [Bayres] built a solution using Arduino and an Ethernet shield.

The main function of this device is to monitor the public IP address and report any changes. This is accomplished by first making a request to checkip.dyndns.org. This website simply reports your current public IP address. [Bayres] uses an Arduino library called Textfinder in order to search through the returned string and identify the IP address.

From there, the program compares this current value to the previous one. If there is any change, the program uses the Sendmail() function to reach out to an SMTP server and send an e-mail alert to [Beyres’] dad. The system also includes a small LCD. The Arduino outputs the current IP address to this display, making it easy to check up on the connection. The LCD is driven by 74HC595 shift register in order to conserve pins on the Arduino.

The system is also designed with a pretty slick setup interface. When it is booted, the user can enter a configuration menu via a Serial terminal. This setup menu allows the user to configure options such as SMTP server, email address, etc. These variables are then edited and can be committed to EEPROM as a more permanent storage solution. Whenever the system is booted, these values are read back out of the EEPROM and returned to their appropriate variables. This means you can reconfigure the device on the fly without having to edit the source code and re-upload.

Power Meter

Solar Panel System Monitoring Device Using Arduino

March 5, 2015 by 10 Comments

[Carl] recently upgraded his home with a solar panel system. This system compliments the electricity he gets from the grid by filling up a battery bank using free (as in beer) energy from the sun. The system came with a basic meter which really only shows the total amount of electricity the panels produce. [Carl] wanted to get more data out of his system. He managed to build his own monitor using an Arduino.

The trick of this build has to do with how the system works. The panel includes an LED light that blinks 1000 times for each kWh of electricity. [Carl] realized that if he could monitor the rate at which the LED is flashing, he could determine approximately how much energy is being generated at any given moment. We’ve seen similar projects in the past.

Like most people new to a technology, [Carl] built his project up by cobbling together other examples he found online. He started off by using a sketch that was originally designed to calculate the speed of a vehicle by measuring the time it took for the vehicle to pass between two points. [Carl] took this code and modified it to use a single photo resistor to detect the LED. He also built a sort of VU meter using several LEDs. The meter would increase and decrease proportionally to the reading on the electrical meter.

[Carl] continued improving on his system over time. He added an LCD panel so he could not only see the exact current measurement, but also the top measurement from the day. He put all of the electronics in a plastic tub and used a ribbon cable to move the LCD panel to a more convenient location. He also had his friend [Andy] clean up the Arduino code to make it easier for others to use as desired.

Arduino Zero Pro Soft Release?

March 4, 2015 by 48 Comments

There’s an updated product page for the Arduino Zero, now called the Arduino Zero Pro, up on Arduino.org, one of the two dueling “Arduinos”.

We first covered the Arduino Zero in May 2014, and shortly thereafter even got to see a development prototype in the flesh. Based an Atmel’s ARM Cortex-M0+ chip, it’s built on a faster processor than the AVR Arduini, and it includes Atmel’s Embedded Debugger which serves as a USB-to-serial channel and on-chip debugging peripheral. But so far all we’ve seen is the prototype.

Now, there’s schematics and Eagle files available that are dated January 7, 2015. The Arduino.org site says that the Zero Pro is “Available now!” but we couldn’t see any in stock yet at any of our favorite online electronics distributors. Maybe we’re looking in the wrong places (unlikely) or maybe it’s just a matter of time.

Anyway, two things struck us in our casual perusal of the new Zero Pro info.

First of all, compared to (pictures of) the prototype versions, there’s more and larger decoupling capacitors scattered all over the board, from the power supply to the Embedded Debugger chip, to a really beefy 4.7uF tantalum capacitor buffering the analog reference voltage level. This suggests there’s been some real-world testing and a shakedown of some of the prototype’s design bugs. That’s all good, and we hope it’s a sign that it’s really coming to market soon.

Secondly, given the ongoing trademark dispute, even the annotations to the schematic for the Zero Pro become interesting. On opening up either the PDF schematic (PDF, naturally) or any of the Eagle files, there’s the usual “Do not finalize a design with this information” boilerplate. But where it used to read “Arduino is a registered trademark. Use of the ARDUINO name must be compliant with http://www.arduino.cc/en/Main/Policy ” it now reads:

“Arduino” name and logo are trademarks registered by Arduino S.r.l. in Italy, in the European Union and in other countries of the world.

(After noticing this change, we went back and compared the “rev3” Uno schematics PDF on arduino.cc to the “rev3E” schematics on arduino.org. Yup, same change in the legal notice.)

We’re not lawyers, but one of the “other countries of the world” that’s conspicuously missing from the claim is the U.S. of A. where Arduino LLC presumably holds the trademark. We’re still trying to make sense of all this, but it’s funny to see the legal battle playing itself out in annotations of Eagle schematics, no?

Stay tuned for more coverage of the Arduino vs Arduino legal battle and, of course, reviews of new hardware as it comes out.

And thanks [Marc] for the tip to the new board release.

Laser-Cut Clock Uses Planetary Gear

March 1, 2015 by 6 Comments

[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.

Fish Feeder

3D Printed Fish Feeder

February 27, 2015 by 16 Comments

[Helios Labs] recently published version two of their 3D printed fish feeder. The system is designed to feed their fish twice a day. The design consists of nine separate STL files and can be mounted to a planter hanging above a fish tank in an aquaponics system. It probably wouldn’t take much to modify the design to work with a regular fish tank, though.

The system is very simple. The unit is primarily a box, or hopper, that holds the fish food. Towards the bottom is a 3D printed auger. The auger is super glued to the gear of a servo. The 9g servo is small and comes with internal limiters that only allow it to rotate about 180 degrees. The servo must be opened up and the limiters must be removed in order to enable a full 360 degree rotation. The servo is controlled by an Arduino, which can be mounted directly to the 3D printed case. The auger is designed in such a way as to prevent the fish food from accidentally entering the electronics compartment.

You might think that this project would use a real-time clock chip, or possibly interface with a computer to keep the time. Instead, the code simply feeds the fish one time as soon as it’s plugged in. Then it uses the “delay” function in order to wait a set period of time before feeding the fish a second time. In the example code this is set to 28,800,000 milliseconds, or eight hours. After feeding the fish a second time, the delay function is called again in order to wait until the original starting time.

LED Sound Board Is Not Your Father

February 26, 2015 by 10 Comments

Who doesn’t like Star Wars, LEDs, and music? [Stathack] was looking for a unique piece of art to put in his living room… so he decided to make his own Vader EQ.

The EQ is a massive 4′ x 5′ piece made from plywood and MDF. [Stathack] traced the familiar helmet onto it by using a projector to project the outline onto the surface. Not having access to an extra large CNC or laser, he then painstakingly used a jigsaw to cut out all the white pieces of the design — holy cow.

This process only took weeks and weeks of sanding, filling and sanding again due to the excellent precision of a jigsaw.

Once that was all done, he created the backing plate out of MDF to provide structural support and mounting locations for the LEDs. Bit of spray paint later and a simple circuit with the Arduino and it’s both done, and awesome.

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Synth Guitar

Arduino Synth Guitar Really Rocks

February 25, 2015 by 18 Comments

[Gr4yhound] has been rocking out on his recently completed synth guitar. The guitar was built mostly from scratch using an Arduino, some harvested drum pads, and some ribbon potentiometers. The video below shows that not only does it sound good, but [Gr4yhound] obviously knows how to play it.

The physical portion of the build consists of two main components. The body of the guitar is made from a chunk of pine that was routed out by [Gr4yhound’s] own home-made CNC. Three circles were routed out to make room for the harvested Yamaha drum pads, some wiring, and a joystick shield. The other main component is the guitar neck. This was actually a Squire Affinity Strat neck with the frets removed.

For the electronics, [Gr4yhound] has released a series of schematics on Imgur. Three SoftPot membrane potentiometers were added to the neck to simulate strings. This setup allows [Gr4yhound] to adjust the finger position after the note has already been started. This results in a sliding sound that you can’t easily emulate on a keyboard. The three drum pads act as touch sensors for each of the three strings. [Gr4yhound] is able to play each string simultaneously, forming harmonies.

The joystick shield allows [Gr4yhound] to add additional effects to the overall sound. In one of his demo videos you can see him using the joystick to add an effect. An Arduino Micro acts as the primary controller and transmits the musical notes as MIDI commands. [Gr4yhound] is using a commercial MIDI to USB converter in order to play the music on a computer. The converter also allows him to power the Arduino via USB, eliminating the need for batteries.

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