ECU Simulator

A simple Python-based Engine ECU simulator using the Controller Area Network (CAN) protocol. This project simulates an Engine ECU broadcasting real-time telemetry data (RPM and Temperature) over a virtual CAN bus (vcan0) and includes a dashboard listener to visualize the data.

Project Structure

• ecu_sender.py: The Engine ECU simulator. It captures keyboard input to simulate acceleration ('w') and braking ('s') and broadcasts CAN frames.
• ecu_listener.py: A dashboard application that listens for CAN frames from the Engine ECU and displays the RPM and Temperature.
• ecu_test.py: Automated tests using pytest to verify the CAN frame structure and ECU logic.
• init_vcan.sh: A shell script to initialize the virtual CAN interface (vcan0) on Linux.

CAN Frame Specification

The Engine ECU broadcasts messages with the following format:

• Arbitration ID: 0x100 (Standard 11-bit ID)
• Data Length Code (DLC): 8 bytes
• Payload Layout:

Byte(s)	Parameter	Data Type	Details
0-1	RPM	uint16	Big-endian unsigned short
2	Temp	int8	Signed char (Celsius)
3-7	Padding	-	Reserved (always 0x00)

Simulation Logic

The ECU simulation runs at a frequency of 10Hz (0.1s intervals).

RPM Behavior

• Idle: The engine starts at a baseline of 800 RPM. When idling without input, the RPM fluctuates slightly for realism.
• Acceleration ('w'): RPM increases by 150 per cycle, up to a maximum of 7,000 RPM.
• Braking ('s'): RPM decreases rapidly by 300 per cycle, down to the idle floor of 800 RPM.
• Coasting: If no keys are held, the RPM naturally coasts down by 50 per cycle until it hits idle.

Temperature Behavior

The engine starts at an ambient temperature of 20°C and warms up to a maximum operating temperature of 90°C based on load:

• Fast Warmup: If RPM is above 3,000, temperature increases by 0.5°C per cycle.
• Standard Warmup: If RPM is above idle, temperature increases by 0.1°C per cycle.

Prerequisites

• Operating System: Linux (required for socketcan and vcan support).
• Python: 3.6+
• Kernel Modules: vcan module must be available.

Setup and Usage

1. Install Dependencies

Install the required Python packages:

pip install -r requirements.txt

2. Initialize Virtual CAN Interface

Run the provided script to set up vcan0. This requires sudo privileges:

chmod +x init_vcan.sh
sudo ./init_vcan.sh

3. Run the ECU Simulator

Start the Engine ECU. It will listen for keyboard inputs:

• 'w': Accelerate (Increase RPM)
• 's': Brake (Decrease RPM)
• Ctrl+C: Exit

python3 ecu_sender.py

4. Run the Dashboard

In a separate terminal, start the dashboard to view the simulated engine data:

python3 ecu_listener.py

5. Running Tests

To run the automated test suite:

pytest ecu_test.py