Physical Computing

Before I switched to design, I studied electrical engineering. During undergrad, I had the opportunity to work on many fun projects that taught me valuable hands-on skills such as breadboarding, soldering, PCB design, programming microcontrollers, CAD, 3D printing, and laser cutting. All of the prototyping skills I've learned through these projects have proven to still be incredibly useful to me as a designer today.

Here is a selection of physical computing projects that I've worked on in the past involving electronic prototyping and digital fabrication.

Dotmote Labs

Dotmote Labs is a startup developing open source hardware and software to help make climate research more accessible.

The Micro-Met Station is an open source meteorological sensor and data logging system that allows for the measurement and recording of temperature, humidity, and wind closer to the ground and at a lower cost than commercial instruments.

The Sapflow Monitor is a sensor and data logging system that measures and records the rate of sap flow through plants non-invasively using the external heat ratio method. The sap flow gauges are low-cost, open source, and easy to install. The data logger can transmit data wirelessly to the cloud and handheld devices.

I helped prototype early iterations of the Micro-Met's circuits and designed early versions of the Micro-Met and Sapflow PCBs.

Skills

Arduino
Electronic prototyping
PCB design (using EAGLE)
Sapflow Monitor in the wild.
Early Micro-Met PCB design.
Early Sapflow PCB design.

Pinball Machine

This project was done as part of the ECE 115: Fast Prototyping course at UCSD. Working in teams of 2, we had 10 weeks to design, prototype, and build a pinball machine.

My partner and I designed a deep sea beach-themed pinball machine. We made sketches and created a full-sized cardboard prototype before making the 3D CAD model. Once the 3D CAD model was finalized, we laser cut pieces out of plywood and acrylic and 3D printed the more intricate parts.

In parallel with designing and building the machine enclosure, we prototyped and tested the circuits and electronic components on breadboards. Once the circuits were finalized, I designed custom PCBs in order to reduce the number of wires and breadboard connections.

The Arduino code to control the electronic components was written piece-by-piece while we prototyped and tested each separate component's functionality on breadboards. For writing the final game code, we created finite state machine diagrams to help us plan and visualize what action should happen when.

View Final Write-Up

Skills

3D CAD (using Autodesk Fusion 360)
Arduino
Digital fabrication (laser cutting, 3D printing)
Paper (cardboard) prototyping
Electronic prototyping
PCB design (using EAGLE)
Cardboard prototype of pinball machine.

LabVIEW Elevator

This project was done as part of the ECE 144: LabVIEW Programming: Design and Applications course at UCSD. Working in teams of 3, we had 5 weeks to design, prototype, and build a model elevator.

After making sketches on paper, we created a 3D model of the elevator in SolidWorks. Although we would make some changes to the design later, this 3D CAD assembly gave us an overall idea of the appearance and dimensions of the elevator.

The control panel circuit was prototyped and tested on a breadboard before being soldered onto a protoboard and mounted onto the enclosure.

The "brain" of the elevator was a National Instruments myRIO. The code to control the myRIO was written in LabVIEW.

View Final Presentation Slide Deck

Skills

3D CAD (using SolidWorks)
Digital fabrication (laser cutting, 3D printing)
Electronic prototyping
LabVIEW
Final 3D CAD assembly of elevator.
Breadboard prototype of control panel.
Control panel soldered onto a protoboard.
Assembled elevator.

Project-in-a-Box

Project-in-a-Box is a student organization that develops projects to teach students engineering concepts in a hands-on way. From 2017–2019, I was part of Project-in-a-Box's outreach division, where I designed and developed science and engineering-related hands-on project kits geared toward middle school and high school students learning in classroom and workshop settings.

Due to our audience, we had some unique constraints to work around when developing projects. We worked with a fairly small budget (>$40 per project) so that project kits could be as affordable as possible to educators who wanted to use them in classrooms or programs. Projects also had to be self-contained and completable within 2-3 hours so they could fit within a class session or workshop. Since we produced all project kits by ourselves in-house, projects had to be quick and easy to produce large quantities of.

Here is a small selection of projects that I worked on during my time in Project-in-a-Box.

Skills

3D CAD (using Autodesk Fusion 360)
Arduino
Digital fabrication (laser cutting)
Electronic prototyping

Ardubot (v1)

Ardubot is our take on the classic Arduino-based obstacle-avoiding robot project. It utilizes an ultrasonic sensor to detect objects in front of it and turns to avoid it. Ardubot has since been updated to v2, but I worked on the initial v1 iteration.

Ardubot v1 3D CAD assembly.
Fully assembled Ardubot v1.
Video demo of the Ardubot sensing my hand and turning to avoid it.

Candy Sorter (v2)

The Candy Sorter is an Arduino-based machine that detects the color of a piece of candy using a color sensor and sorts it into a corresponding cup. This project is an adaptation of How to Mechatronics' Arduino Color Sorter. I worked on the second iteration of this project, which improved upon the design and performance of the initial version.

Candy Sorter v1 (before our v2 revision).
Candy Sorter v2 in action.
Projects
QuLabStellarHelply
© 2022 Angela Xu