Senior Capstone

Context

• My senior capstone project at Olin College towards a Bachelor’s in electrical and computer engineering.

  • Work on the project took place over a full academic year in a team of three mechanical engineering students and two (including myself) electrical and computer engineering students.

• We delivered a documented, tested prototype for a compact energy harvesting system on behalf of Watts Water through Olin’s SCOPE program.

  • The goal for the project was to harvest energy from the pressure drop between the municipal water supply and the home water system.
  • The implementation consisted of a high-pressure flow chamber containing a turbine attached to an actively-controlled regenerative braking system.

Responsibilities

Sole

• The regenerative braking firmware implementation, including electrically modeling the turbine/motor system and controlling the motor to extract power.
• In my role as the team’s business manager, procuring raw materials, test boards, electrical component orders, manufacturing, and other miscellaneous items.

Shared

• With our other electrical engineer, for block-level system design, component selection and testing using development boards.
• Also with our other EE, testing our manufactured PCB and our full electromechanical system. Before we had a finished mechanical system or testbench, this required some creativity.

Skills

• Rust
  • We wrote our firmware in Rust, partially for its robust embedded support and partially as an educational opportunity.
  • I got comfortable using Rust’s #![no_std] environment, as well as the cargo toolchain management and easy flashing.
• STMF3
  • We used an STMF303 microcontroller as the brains of our application’s PCB, because of its motor controller support and ADCs.
  • Towards the end of the development cycle, we recommended an STML4-series microcontroller due to its lower power consumption and highly-efficient standby modes.
• Power Electronics
  • I used the Piecewise-Linear Electrical Circuit Simulation (PLECS) software to model the motor control aspects of our system because of its efficient switching simulation.
  • I successfully adapted the 3-phase brushless DC motor into a power turbine capable of extracting up to 0.5 watts in normal operating conditions.
• Communication
  • We had weekly progress meetings with our Watts handler, Joe Burke, as well as several design reviews and presentations during the course of the academic year.
  • Extensive technical documentation was a significant part of our final deliverable, as well, as the project was picked up by Watts engineers after our year ended.
• Teamwork
  • We had the same team of five across the whole year, which meant communicating interpersonally to ensure we were all working in the same direction.
  • It also meant selecting and using appropriate project management tools. We used Notion.