2024-2026 Electromechanical Electrical PDR Notes

SOM (System on a module)

• Package = SOM (MCU, CAN, POWER) + Daughter Board (System Specific Circuitry)
  • Controls
  • BPS
  • Data aq
• Leader SOM
  • same for all systems
  • sits on top of the daughter board (like a hat)
  • Power Connector → Voltage Regulation (12v → 5v)
  • STM32F4 (MCU) → Car CAN, 7-seg disp, Micro USB, SD Card, Daughter Board (customized to each system)

Controls

• Leader-Daughter Package (Controls specific/system specific)
• 4x Peripheral
  • Front Blind spot x2
  • Rear Blind spot + lights x2
• CAN
  • Controls CAN
    • 4x peripheral board
• 7 in display - comms thru RPi (UART from controls, HDMI to display)
• speaker/buzzer implementation
• only 1 motor design
• cruise control - up and down buttons to control speed
• driver fans
  • analog potentiometer to controls → fan to control speed
• steering wheel buttons
• blind spot detection
  • 2 on each side
    • 1 angled back positioned at the front
    • 1 perpendicular in the rear
• Motor controller requires 12V CAN, peripheral boards require 5V, weird cabling, but theoretically more robust

BPS

• Leader
• 2x Peripheral SOM
  • VoltTemp
  • Amperes
• Car CAN (all electric systems)
• BPS CAN (in lieu of IsoSPI)
  • volt, temp, current, other battery data
• support for 2, 3, and 4 pin fans via I2C
• support for up to 3 contactors + individual sense pins
• BPS Leader design
  • Leader SOM
    • Fan (via I2C)
    • 3x Contactor Drivers
    • Strobe Lights
• Peripheral SOM
  • CAN → STM32L4 (requires 5v to 3.3v) → micro usb, back to daughter board
• VoltTemp Boards
  • voltage
    • 16 Battery Cells per stack
    • support for I2C instead of IsoSPI
    • Battery → peripheral board → peripheral SOM mcu
  • temp
    • 16 channel mux/adc
• Amperes Board
  • monitor Shunt Temp
  • CAN via peripheral
  • more accurate state of charge
• support for Orion BMS Still there (backwards compatible)
• connecting Fan connector to Orion to still run fans

Power Systems

• PCB Design for VoltTemp
  • Each thermistor and volt tap of each segment would connect to PCB that spans length of segment
  • solid vs bolted nickel plates
• driver boards for precharge contactors
  • burn off extra voltage during startup when balancing voltage
  • internal to power systems
• same 3d printed brackets, new cell design
• 4 segments, 8 modules each, 9 cells in each module
• ignitions switch
  • remove controls from the process
• external integration
  • more modular/compact battery pack
  • HV Power Optimization with BPS
  • Ignition (No more controls, only with BPS

Data Aq

• 2nd Telemetry CAN bus
  • only data aq sensors
    • IMU, temp, steering, etc
  • peripheral daughterboard package
• Car CAN
  • messages from electrical systems
  • optimal speed output
• Wireless transmission to chase car via radio
  • XBEE
• Sensors
  • Peripheral Daughterboard
    • IMU
    • Humidity Sensor
    • Hall effect Sensor
    • Airflow Sensors
    • Temp Sensors
  • analog/I2C
• Hall Effect or Potentiometer on Steering Column
  • Hall effect will require extra shielding on the wiring
  • magnet placed on the steering column