Projects that I do in my free time may not always see completion or work 100% as intended but they typically turn out to be useful ways to learn and occasionally turn out as things I use daily. I have been influenced by the idea of repair cafes, giving something a second chance that many consumers would likely throw out, even designing extra features the original did not have. In a similar fashion I am influenced by DIY/Maker culture where the idea of reproducing technology from consumer accessible items and making it available for others to criticize and contribute to is just as important as creating the initial artifact.
picutter: Raspberry pi Laser Cutter
Inspired by the various laser cutter projects on instructables (here, and here) I wanted to create my own as well. Instead of taking their approach and using Arduino and some of the more standard CN software (GRBL) I wrote my own using the raspberry pi as the controller. The pi also runs the software interface which can open files and converts them as necessary for the pi to run the print. One version was written in Python and the final version in C++ using Open frameworks.
The actual laser cutter itself was built from a component rack that was rescued from the trash. The components were 3d printed and designed to specifically fit in the component rack. The laser was bought on eBay and is a 2W 445nm laser along with a SPI controlled TTL laser controller. The outside of the rack is covered in a thick red acrylic to prevent radiation from the laser from scattering out and blinding others though laser goggles should always be worn when dealing with class IV lasers.
Brain & Heart Pendent
This pendent was made for a friend who had recently been accepted to a neuroscience PhD program and based off a schematic of a charlieplexed Christmas tree (Sorry the original site is down so heres a stackexchange about it) The LEDs are tied to brain readings I had taken from them for another one of my projects and converted into Boolean values once they passed a certain threshold. These were stored in an array where each Boolean value was saved as a bit value spread out over three 8bit data objects. This was done to maximize the length of the readings as the ATTiny ran out of memory very quickly otherwise.
The circuit design was done in Fritzing and actually had an error the first time it was printed which I fixed for the second printing. The pendent was made from layers of wood that was laser cut and the center was a laser etched mirror plated acrylic. One side held a rechargeable lithium battery with a cord that could be connected to the second half to run the led animation.
Repairing a broken water heater bought from a thrift store for 6%
Using an old microwave transformer to create a simple spot welder