Engineering Design Projects
Engineering designs, schematics, diagrams, etc.
Projects List (click to jump to project):
Below, please see the links to the NER git repository, where we use version control for all electrical schematics, as well as a link to the Formula Hybrid website.
Below are some of the projects I have led and completed.
Fully Electric Racecar - Acccumulator Layout and Assembly. I designed the layout of the electronics in this accumulator and was a lead electrical engineer overseeing the design of the accumulator. From January-May 2022 I performed the initial electrical assmebly of the box as well as testing of the various systems along with fellow engineering students. Seen below is the High Voltage plate, Low Voltage plate, and the accumulator in its entirety disassembled on the workbench for battery segment maintenence.
NER: Transition to Master Schematic with Version Control
This Master Schematic has been in use since then and is actively changing (via Git version control) as we edit the design of the car.
Having a Master Schematic allows us to properly communicate our design both internally and externally.
Use the button below the image to view the latest version of our schematics for the vehicle using CadLab, a git compatible in-browser CAD viewer
Battery Management System Integration
Voltage Tap Isolation PCB
This PCB was designed to isolate and connect the cell voltage taps on our 18650 cell based accumulator to an Orion BMS 2 battery management system. The parallel cells will be monitored and balanced via this PCB.
Thermistor Fusing and Splitting PCB
This PCB simply takes 22 thermistor inputs and their 22 grounds, and shorts groups of six as per the Orion BMS requirements. Because the thermistors are located next to the accumulator cells and exit the battery container, they are each fused at 1A for safety. 2 Critical thermistors (for general pack temperature sensing) are split and processed separately.
More Info:
This R&D involved designing an implementation for an off-the-shelf battery management system (the Orion BMS 2). Some special considerations for this integration into our vehicle system included utilizing a multi-purpose open drain output on the BMS to drive a relay in the safety system described below which can be used to open the "shutdown safety loop" in the car - which needs to be closed in order to hold the main tractive system voltage contacts open.
Other considerations and desgins included a special power management board using MOS-FET logic to control the charging states. I designed the original circuit using relays, but my teammate Zach greatly improved the designs power and space efficency by converting it to MOS-FET logic.
Shutdown Safety System R&D
This was one of the first systems for which I led R&D for our Formula Hybrid entry. I generated the block diagram above in order to explain to team members the safety circuit for the vehicle. This system follows very strict technical rules for Formula Hybrid, and offers multiple methods for shutting down Tractive System power in a multitude of failure modes (some controlled by safety cut-off switches, and some controlled digitally [IMD and BMS output]. The schematic on the right is a summary of the shutdown related components taken from the master schematic, omitting non-relevant sub systems.
