VCU3.0

E-GoCart VCU Firmware

Vehicle Control Unit (VCU) firmware for an electric go-kart, built on ESP32-S3 with FreeRTOS. Manages motor control, battery management, charging, telemetry, and safety systems over dual CAN buses.

Hardware

Battery — Racepow RP-SSB-1174170

Software Architecture

12+ FreeRTOS tasks split across two cores:

Core 0 — Real-time / safety-critical

• CANRx (P24) — CAN message ingestion
• CANTx (P23) — Motor torque commands at 10–50 ms
• VehicleControl (P22) — Throttle/regen → torque demand
• StateManager (P21) — State machine (Sleep → Init → Ready → Drive/Charging)
• SafetyMonitor (P20) — Temperature, voltage, interlock watchdog

Core 1 — UI / networking

• InputManager (P10) — Buttons, switches, ADC reads
• DisplayManager (P5) — Nextion HMI updates
• WiFiManager (P4) — AP mode + optional STA
• WebServer (P3) — HTTP REST + WebSocket telemetry (50 ms)
• TaskMonitor (P2) — Per-task watchdog & auto-restart
• LEDControl (P3) — Status LED patterns
• ErrorAggregator (P4) — Cross-subsystem error collection

Vehicle State Machine

SLEEP ──(start/charger)──> INIT ──(precharge ok)──> READY
                                                      │
                                          ┌──────────┴──────────┐
                                        DRIVE              CHARGING

WiFi & Web Interface

• SSID: E-GoCart-VCU | Password: egocart123
• IP: 10.1.109.191
• Real-time WebSocket telemetry: speed, power, SOC, temps, errors
• OTA firmware update endpoint
• JSON configuration API

Building & Flashing

Requires PlatformIO.

# Build
pio run

# Flash
pio run --target upload

# Monitor serial
pio device monitor

OTA updates are also supported via the web interface at http://10.1.109.191.

Project Structure

E-GoCart/
├── src/main.cpp          # Main firmware entry point & all FreeRTOS tasks
├── include/
│   ├── config.h          # Pin map, CAN IDs, safety limits, tuning params
│   ├── data_structures.h # Shared state structs
│   ├── can_manager.h     # Dual CAN bus abstraction
│   ├── bms_manager.h     # Battery management
│   ├── nlg5_manager.h    # NLG5 onboard charger
│   ├── vehicle_control.h # Torque calculation
│   ├── state_manager.h   # State machine
│   ├── contactor_manager.h
│   ├── display_manager.h
│   ├── input_manager.h
│   ├── wifi_manager.h
│   ├── web_server.h
│   └── task_monitor.h
├── data/www/             # Web UI static files (LittleFS)
├── platformio.ini        # Build configuration
└── PinOut.csv            # GPIO pin reference

Safety Features

• Emergency interlock kill (hardware switch)
• Motor/inverter/battery overtemperature shutdown
• BMS communication loss → immediate torque cut
• Precharge sequencing before main contactor closure
• Current verification before contactor switching
• Per-task watchdogs with auto-restart

Releases