Tools/fake-wheel/README.md

Fake Gaming Wheel Emulator

Virtual USB gaming wheel device emulator for Linux. Creates a fake Logitech G29 Racing Wheel for testing purposes.

Quick Start (Recommended)

Use the uinput version - it's more reliable:

sudo python3 fake_wheel_uinput.py

Files

• fake_wheel_uinput.py - Uses /dev/uinput (RECOMMENDED)
• fake_wheel.py - Uses /dev/uhid (alternative, more complex)
• debug_uhid.py - Debug script for uhid
• check_wheel.sh - Check if device appears

Features

The emulated wheel provides:

• Steering Wheel: Full 900° rotation (±450°)
• Throttle Pedal: 0-100% range
• Brake Pedal: 0-100% range
• 16 Buttons: Standard gaming buttons
• USB Device ID: Logitech (0x046d) G29 (0xc24f)

Simulated Behavior

When running, the script automatically simulates:

• Steering wheel rotating left/right in smooth sine wave
• Throttle pulsing between 0-78%
• Brake activating every 5 seconds
• Buttons cycling through 1-16 in sequence

Verification

Check if the device appears:

# Method 1: Check by-id
ls -l /dev/input/by-id/ | grep -i logitech

# Method 2: Check input devices
cat /proc/bus/input/devices | grep -A 10 "Logitech G29"

# Method 3: Use evtest
sudo evtest
# Then select the G29 device from the list

# Method 4: Use jstest (for joystick interface)
jstest /dev/input/js0

Requirements

• Linux kernel with uinput support
• Python 3.6+
• Root access OR user in 'input' group
• uinput kernel module (usually loaded by default)

Enable uinput module (if needed)

sudo modprobe uinput
# Make it permanent:
echo "uinput" | sudo tee /etc/modules-load.d/uinput.conf

Run without sudo (optional)

Add udev rule to allow non-root access:

echo 'KERNEL=="uinput", MODE="0666"' | sudo tee /etc/udev/rules.d/99-uinput.rules
sudo udevadm control --reload-rules

Or add your user to the input group:

sudo usermod -a -G input $USER
# Log out and back in for changes to take effect

Troubleshooting

Device doesn't appear

1. Check if uinput module is loaded:

   lsmod | grep uinput
   

2. Check permissions:

   ls -l /dev/uinput
   

3. Check kernel messages:

   sudo dmesg | tail -20 | grep -i input
   

Test with minimal script

Run the debug_uhid.py to test basic functionality:

sudo python3 debug_uhid.py

Usage in Your Testing App

Once the fake wheel is running, it appears as a real USB device. Your gaming wheel tester should detect it automatically as:

• Device Name: "Logitech G29 Racing Wheel"
• Vendor ID: 0x046d (Logitech)
• Product ID: 0xc24f (G29 Racing Wheel)

The device will show up in standard input device APIs:

• /dev/input/eventX (evdev)
• /dev/input/jsX (joystick)
• SDL2, pygame, etc.

Stopping the Emulator

Press Ctrl+C to cleanly stop and remove the virtual device.

Technical Details

uinput vs uhid

• uinput: Kernel interface for creating virtual input devices. Simpler API, better for basic input devices.
• uhid: Kernel interface for userspace HID drivers. More complex, allows full HID descriptor control.

This project provides both implementations. The uinput version is recommended for most use cases.

Device Specifications

• Bus Type: USB (0x03)
• Axes:
  • X (Steering): -32768 to 32767
  • Y (Throttle): 0 to 255
  • Z (Brake): 0 to 255
• Buttons: 16 buttons (BTN_TRIGGER + 0-15)
• Update Rate: 100 Hz (10ms intervals)

License

Free to use for testing and educational purposes.