Design Residency at Voxel8
Loving all the praise we are receiving at CES! Check out 3D Printing Industry's Post on how my demos put the 'Fun' in 'Functional'!
In the Fall of 2015 I began a design residency with Voxel8, a multimaterial 3D printing electronics startup out of Professor Jennifer Lewis’ group at Harvard. We have the ability to print highly conductive silver and thus embed electronic circuits into 3D printed parts. My residency focuses on designing and creating tools to facilitate the creation of everyday devices by non-experts, including Legos with conductive pegs, wireless inductive powered components, and smart watches.
In order to facilitate removing the barrier to entry of designing circuitry, I designed and printed a Voxduino, Voxel8’s in house Arduino board that can be printed and stuffed using our printer, but programmed through the Arduino IDE. On the other end of the expertise spectrum, I am helping create an add-in to the 3D CAD tool SolidWorks to allow users with electrical engineering backgrounds the ability to import and embed 2D circuits designed in Eagle into 3D models in SolidWorks. With both of these tools and the ability to embedded conductive traces into any 3D model, people can now create devices that do not follow the form factor of popular prototyping boards, making it easier to design devices around their use, and not around an electronics package.
I must admit that I could not have found a more perfect match to explore DIY technologies. They essentially gave me access to their printer and let me loose! Mechanical, electrical, and software skills were honed while rusty exposures were solidified. And as I grow, I find that videos are the best way to communicate my ideas, so check out these videos of my work (Details of each project are also below for those of you who are more text-friendly).
3D Printed Watch
Wearables is a huge market, and I wanted to make a demo that expressed this for the Consumer Electronics Show. The following images show the design process for creating this watch. The schematic was first designed in Eagle and a board was exported. Using our in-house SolidWorks Add-in, I imported the board and SolidWorks created a 3D board, along with traces and components. I manipulate this file to fit the form factor of the watch I want to design. After specifying a material (plastic or silver) for each body, the add-in exports all bodies into three files corresponding to the material. The three STL files are then sliced using Euclid, an open source slicer. Just upload to our cloud based system and press print! The printer will pause at component insertion to allow you to, well, insert a component. I programmed the ATtiny board prior to insertion. Put the watch on and boom, you have your own 3D printed electronic watch in a matter of hours.
In this demo, I used three Lego bricks to create a circuit. The large piece holds a coin cell battery, a second piece has an embedded LED, and the third houses a reed switch. The pieces have pogo pins to create connections. When all three are placed on the base and a magnet is brought near the reed switch, the LED on a separate lego brick will turn on!
I would love to explore this demo further to show how easily it is to build circuits from components by stacking them together. Although found after these Lego pieces were made, others have also explored DIY building blocks, including Little Bits and the LittleDevices MEDIkit. The LittleDevices Lab at MIT does a similar thing but for medicine.
If you remember your introduction to electricity and magnetism course, you likely be able to understand how an LED can magically turn on when placed in proximity to a base. An alternating current on a base coil induces a changing magnetic field. The flux of this magnetic field changes in the receiving coil, inducing a current in the second coil that turn on the LED.
You may be wondering why the LED is blinking. Well, thats because the base I had laying around utilizes the Qi (pronounced "chee") charging protocol used on many smart phones, which checks for inefficiencies in tranfer. Since the LED is not being charged, it keeps "resetting" to try and create a better connection.
In case you dont want or have the ability to design your own boards, this project explored how to connect to already build boards. Here, a cavity is printed for the board, and the silver is printed directly on top of the board to control motors and LEDs. This approach lets you completely change the form factor of anything you have already designed. The connections to the motors are made through magnets and ball bearings.
Printed Circuit Boards
In this demo, I was testing the limits of how close the voxel8 printer can print. I was able to print to a TQFP footprint, which has a 0.8mm pitch. The reason I chose this is because I wanted to use an ATmega328p microcontroller to create a Voxduino, an in-house 3D printed arduino.