PHYS250H: Power Supply Project II

Screen Shot 2014-10-31 at 9.37.38 AM.png
The printed circuit board design is a projection of the schematic design. The placement of the footprints for the set of jumpers was positioned intentionally to allow for the power lines to be connected simultaneously as well as for easy access when soldering. We went through several iterations in design due to mishaps in communication -- a key issue in engineering firms. It took me a little while to understand just exactly how Battat envisioned this project and the best way to design such. At first, different components were in place than in the final design: I moved from three-way jumpers that resembled the slapstick original design for the Electronics Lab (without direct input into the rails); to long rectangular flow mirroring the circuit schematic; and to a dual-pin jumper and stacked 805 footprints. Finally, I ended with a reasonable and compact design for the PCB power supply. OSH Park, a community printed circuit board order, charges $5 per square inch of a dual-layer board (including three copies of that board), and, hence, the board is designed for all components on one side and a plane of copper on the opposite side. A compact design decreases costs incredibly: resistors and capacitors are configured like a sliding block puzzle and placed away from footprints with tall components, which would create difficulties in soldering small components. The components are configured along the five-pin DIN connector, where voltage levels come in, for minimal open space, and vias are used to ground pins to the copper plate on the opposite side.


The cost of the complete board totaled US$13.25 for a set of three 2.652 square inch dual-layer boards. The estimated date of arrival is roughly twelve days from fabrication: we can expect the finished board to arrive around the second week of January 2015. The product has shipped and arrived at the Science Center, which allows the board to be assembled as it would in the PHYS310 laboratory assignment and tested to ensure proper connection and usefulness. If this version proves accurate, it will be ready for implementation for the spring course.

Comments

Post a Comment

Popular posts from this blog

Hackathon: TechTogether Boston

Image
iOS app Last weekend, I had the wonderful opportunity to participate in Boston's largest all-female and non-binary hackathon! A group of friends and I wanted to digest as much tech and nerd information as possible, and we basically made it our mission to go to nearly every workshop session offered for two days straight. I don't know how we managed this but we did. From 5p on Friday and all day on Saturday, it seemed I bounced from one room to the next with a nap here and there. There was a workshop on rapid prototyping with AdobeXD -- which I am in love with. Then, I was able to create my first phone application during a workshop on iOS app development with Swift  (it's much easier than I had imagined), followed by a workshop at 2am on Android app developmen t. For my very first hackathon-conference, I wanted to focus on skill development and learning, rather than the competition. However, seeing everyone so wrapped up in their individual designs and programming ...
Read more

Women of Color in Graduate School

Image
Recently, I've been asked (by a few people) how it feels to go through graduate school as a woman of color. And, to be completely honest, it's incredibly exciting and exhausting all at the same time. Being a woman of color -- specifically a black woman, particularly in STEM -- has a lot of challenges. If you simply search the phrase "black in graduate school," you will get statistics that are very humbling; articles and think-pieces on how different the Black or person-of-color experience is from students who are not minorities; and other outlets detailing how little support many Black and non-Black students of color feel that they have. In fact, the Council on Graduate Schools recently reported that, in 2017, Black students made up just 11.9% of all first-time graduate students in the United States. (That said, 68% of them were women! So, we are making p r o g r e s s.) I'm not sure what the numbers are at Boston University, but it doesn't seem that far o...
Read more

Truss Design (Final)

Image
We finally made it to the end! After the preliminary design report, it was time to finalize our actual design (since we were given enough materials to make one truss to test). After doing a few more draft sketches and analysis, I was able to pick up on patterns on which types of designs produced the maximum strength (all within the parameters we were given). Finally, I came up with the sketch at the bottom-right, and the MATLAB analysis produced the highest load we were able to reach. We theorized that: two members would buckle first instead of just one (Members 3 and 4); the maximum load is 11.62 ± 0.063N; and the total cost of the truss is $290 (under the budget limit). From there, we moved to prototyping: we cut the straws as close as possible to the lengths specified in our final design. To create uniform gusset plates, our "joints," we used the circular cap of an individual Tropicana Orange Juice bottle. It met the area requirements and acted as a stamp...
Read more