DIY Earthquake Detector

June 8, 2011 by Jeremy Cook 20 Comments

Some animals seem to be able to detect earthquakes. Some animals also navigate using the earth’s magnetic field. From the idea that there may be some relationship with these two things, this experimental earthquake detector was born. [Bob Davis] built this device, which uses an Arduino and several Hall effect sensors to detect and record magnetic fields. Possibly after enough data is recorded, a correlation can be found between the two phenomena.

The sensors in this device are arranged to measure magnetism in four directions as well as in the vertical axis. Part of the idea behind this is that before an earthquake the quartz in the ground moves producing a magnetic field.

In the video after the break, Bob gives some background on the theory behind this device and talks about the first version (built way back in the year 2000) which uses a PC for control and recording. Really interesting stuff so be sure to listen to Bob’s explanation after the break. Continue reading “DIY Earthquake Detector” →

ChipKIT Sketch: Mini Polyphonic Sampling Synth

June 8, 2011 by Phil Burgess 20 Comments

In our hands-on review of the Digilent chipKIT Uno32, we posed the question of what the lasting appeal might be for a 32-bit Arduino work-alike. We felt it needed some novel applications exploiting its special features…not just the same old Arduino sketches with MOAR BITS. After the fractal demo, we’ve hit upon something unique and fun…

Continue reading “ChipKIT Sketch: Mini Polyphonic Sampling Synth” →

Capturing Video With An Arduino

June 7, 2011 by Brian Benchoff 10 Comments

[Carlos Agell] sent in a tip where he captured images from an analog camera with an Arduino.

We’ve seen a few AVR/Arduino hacks that generate video, although overclocking is necessary if you want to do anything beyond a Breakout clone. [Carlos]’ hack bucks that trend and now he can capture video with an Arduino.

The project captures individual frames from NTSC video at a resolution of 128×96. Although the Arduino isn’t powerful enough for real-time capture, [Carlos] managed this by capturing only thresholds and sending them over to a computer running a program coded in LabVIEW. The PC program reassembles the images of the thresholds and produces a tiny image in 3-bit grayscale.

[Carlos] used the Video Experimenter shield which is impressive in it’s own right. The Video Experimenter is able to do object tracking and edge detection, so we’re wondering when we’ll see robots with computer vision running off an Arduino. Check out a demo of the nootropic design video experimenter shield after the break.

UPDATE: Carlos wrote a sketch in Processing that does the same thing as his LabVIEW program.

Continue reading “Capturing Video With An Arduino” →

Precision Frequency Measurement Library For 8-bit Microcontrollers

June 3, 2011 by Mike Szczys 7 Comments

[Paul] has been working on porting over Arduino libraries for use with the Teensy microcontroller platform. This tends to be pretty simple since they both use the same Atmel chip architecture. But once in a while he finds the Arduino libraries are not what they’re cracked up to be. When looking to port over a frequency measurement library he ended up writing his own that works better and is much more portable.

He had two big beefs with the Arduino Frequency Counter Library. The first is that it required the compensation factor the be calibrated using an accurate frequency counter. That’s a chick-and-egg problem since many people who build a frequency counter with an Arduino are doing so because they don’t already have a standalone tool. The second problem is that the Arduino library was hardcoded for ATmega168 or ATmega328 chips.

This new library fixes both issues with just one trade-off. Your hardware setup must be using a crystal oscillator. You can see above in the image above that the frequency measurement is quite accurate with this method. The package also uses a thin abstraction layer which will make it easy to port to any 8-bit microcontroller which is programmed in C.

Fan Throttling For PS3 Temperature Control

June 2, 2011 by Mike Szczys 10 Comments

This setup will let you monitor Play Station 3 temperatures and throttle the cooling fan accordingly. [Killerbug666] based the project around an Arduino board, and the majority of the details about his setup are shared as comments in the sketch that he embedded in his post. He installed four thermistors in his PS3 on the CPU heatsink, the GPU heatsink, the Northbridge or Emotion Engine, and one in front of the air intake grate to measure ambient room temperature.

Above you can see the setup he used to display temperatures for each sensor on a set of 7-segment displays. The project also includes the ability to push this data over a serial connection for use with a computer or a standalone system.

The project is still in a prototyping stage. It works, but he likens the fan throttling to the sound of a car engine constantly revving. Future plans include smoothing out the fan speed corrections and scaling down the size of the hardware used in the system. We’d suggest doing away with three of the displays and adding a button that lets you select which set of sensor data you’d like to display.

[Thanks User]

Cheap And Cheerful Arduino Breadboard Basics

June 1, 2011 by Jesse Congdon 8 Comments

For those less experienced folks looking to move their Arduino projects to more permanent installations, this is just for you! [Martyn] Posted a three part series, VeroBoardUino, over at his blog about moving your Arduino project to a soldered breadboard.

Part one kicks off with the appropriate breadboard requirements, modifications, and a simple 7805 power supply. In the guide [Martyn] is using strip board, so copper connections will have to be broken using a drill or just by scraping with a hobby knife. Strip board also saves a bit of wire routing in the end. Part two handles the reset button, serial connection and chip socket (Part 2.5 has also been added to include schematics of the breadboard). Finally, part three installs the crystal and connects your Atmega chip to power and ground.

Next post he will be covering more on the software end of things, burning the bootloader and uploading programs to your new board so stay tuned for updates!

Prototyping The New Office Clock

June 1, 2011 by Mike Szczys 10 Comments

[Damage] was tapped to build a new clock to hang on the wall at the office. He got a hold of some 6.5 inch seven segment displays for the hours and minutes, as well as some 4.5 inch modules for the date and month. Rather than jump right in with the large hardware (especially because he’s waiting for the PCB order to arrive) he built this prototype with more commonly sized displays.

His build is Arduino powered. In the video after the break he mentions the temperature compensated crystal oscillator that keeps the time. We’d wager that’s the DS3234 based RTC module that Sparkfun sells. This is the same chip family as the Chronodot and it was our choice for the Ping Pong Clock.

The finished clock will hang high on wall, out of reach when you need to set the time. This shouldn’t need to be done much – if ever – since that RTC includes a backup battery. But [Damage] took the time to develop a remote programming device anyway. Using another Arduino, an LCD display, and an Xbee pair he whipped up a remote that can be used to navigate and change the main unit’s settings.

Continue reading “Prototyping The New Office Clock” →