Replay and simulation
Use actual-log replay for investigating problems and a separate simulator for development experiments.
| Tool | Input | Purpose |
|---|---|---|
| Carrot Web Replay | Drives stored on the device | Video, HUD, events and graphs together |
| PC Replay | Driving message logs | Replay recorded messages in a development environment |
| MetaDrive | Virtual driving scene | Development simulation |
Easiest start
Find the affected segment in Carrot Web → Logs → Dashcam and choose Replay from its menu. Available views depend on saved inputs and browser support. Replay does not control the real vehicle.
PC development setup
Follow the current branch's dependency/build instructions. Do not copy the old v7-wip3-wd40 branch, arbitrary graphics PPAs or obsolete VM settings as a current procedure. A complete native Windows development environment was not validated for this guide.
Paths relative to the repository root:
openpilot/tools/replayopenpilot/tools/simopenpilot/tools/plotjuggleropenpilot/tools/cabana
MetaDrive uses two processes
In a prepared development environment, use openpilot/tools/sim/launch_openpilot.sh in one terminal and openpilot/tools/sim/run_bridge.py in another. Check each file and the current README for working-directory requirements before starting.
| Key | Current sim README action |
|---|---|
| 1 / 2 / 3 | Cruise accelerate / set-decelerate / cancel |
| WASD | Manual control |
| r / i / q | Reset / toggle ignition / quit |
Simulation and replay do not replace real-vehicle validation of harnesses, ECUs or safety.
Source reference
Reference checked 2026-10-30 · carrot-wip · 10bf0a56.
openpilot/tools/sim/README.md · openpilot/tools/replay/README.md · docs/user/ko/carrot-web.md
The development branch continues to change. Check your device’s branch, commit and current settings together.