January 2011 - August 2011
University of Washington


- Project Skills
- Machining
- Solid Modeling
- Rapid Prototyping
- Arduino Programming
- Wiring
- Teamwork
- Leadership
Current 3D powder printers work by spreading a full layer of build material, then selectively applying binder to areas until the layer shape is formed. This process is repeated, eventually producing an object. Full color models can be built through changing the binder color.
The Project

Powder deposition attempts to minimize waste by limiting the unused powder that is placed on the build platform to support material. The current iteration of the print head can use two different build materials, and the concentration of each powder at a given point is controlled by pulse width modulation. A large scale version has been installed on Big Red, a former plasma cutter that has been turned into a 3D printer.
The powder is deposited through the use of vibrating motors which loosen the powder from individual nozzles. Since it was desired to control multiple powders and vary the concentrations of each, a feed plate like the one seen on the right was developed. By rotating the plate, the number of holes would vary and restrict the volume of powder released.
The feed plate is rotated by a stepper motor, which moves according to instructions from a data file. The data file contains a series of numbers from 0 to 15, each one assigned to a particular cluster of holes. An Arduino reads the data file and drives the stepper motor until it reaches the appropriate orientation.

The print head was my senior design project at the University of Washington. I worked as a part of a team to develop a large-scale 3D printer from January to June of 2011. Reports about my work can be found below in the Documentation section.
- Completed Tasks
- Modeled prototype in Solidworks
- Programmed flow rate controls in Arduino
- Wired flow rate controls and vibration motors for deposition
- Built prototype by ordering and machining raw materials
- Used 3D printing to create a quick mold for the feed plate
- Received input from teammates and adviser on a weekly basis
Documentation
Winter 2011 |Exploration of Multi-Material Additive Manufacturing|
Spring 2011 |Development of a Multi-Material Powder Print Head|
Summer 2011 |Multi-Material Powder Print Head Project Update|
Code
Processing |Preprocessor for a 4-bit grayscale image|
Arduino |Firmware|