Create a video
- Complete a Quarter-Car or Half-Car Transient Study and open Motion.
- Select Export Video. Choose Model or Vehicle, and 0.5×, 1× or 2× speed. Vehicle offers 3/4 and Side cameras.
- Generate the video. Progress counts rendered/encoded frames; Cancel stops further work. Keep the tab open until the download finishes.
The fixed preset is 1920 × 1080, 16:9, 30 fps with physical metrics, original road trace(s), simulation time and a fixed “Generated with VehicleLab” watermark. No audio is added. The maximum output duration is 120 seconds.
Completed evidence and deterministic timing
Export reads the last completed Study, even after input edits. The panel identifies stale evidence; restoring the completed definition exactly restores current status. Export captures its source and settings when generation starts. Changing drafts or interactive playback cannot replace that source.
For physical duration D and speed s, output duration is D/s. Frame n starts at n/30 output seconds and samples physical time s·n/30. There are ceil(30·D/s) frames. The final interval is shortened if needed. The exact endpoint closes the final interval; it is not duplicated as an extra frame. A 5 s study at 1× yields 150 frames and 5 s of video. At 2× it yields 75 frames and 2.5 s. Interpolation is for display only; physics is never rerun and stored channels remain unchanged.
Read the engineering context
Readouts show physical acceleration, suspension travel and tire deflection for Quarter-Car; Half-Car shows body acceleration, pitch and front/rear travel. Units are always displayed. Vertical motion is amplified with the same completed-data envelope used by Motion. The gain is disclosed; it does not scale numerical readouts. Half-Car visible pitch follows amplified attachment geometry. Quarter-Car Vehicle wheels mirror one vertical corner and do not imply pitch or roll dynamics.
Front/rear road traces and pads represent prescribed axle inputs, not a spatial road reconstruction. Generic models are not measured-vehicle correlation or engineering recommendations.
Browser support and local processing
The browser must provide WebCodecs VideoEncoder and VideoFrame in a secure context (HTTPS or localhost) with a supported 1080p codec. VehicleLab probes actual support, preferring MP4/H.264 and otherwise WebM/VP9. The panel names the selected format before generation. Codec availability depends on browser, OS and hardware; unsupported environments receive an explicit reason. There is no real-time recording fallback.
Vehicle export additionally requires WebGL. A missing module, unavailable context or context loss stops that export explicitly; select Model to use Canvas without WebGL. Response, projects and reports remain available. Encoding failures do not alter completed evidence.
Rendering, encoding and download happen locally. Nothing is uploaded. The encoder/muxer loads only when opening the video panel; Three.js loads only for Vehicle. Export owns its canvases and scene, awaits encoder backpressure and releases resources afterward. Final container writing may finish internally after cancellation, but the canceled artifact is not downloaded.
Limits of v1
Transient Study only. Compare, Frequency, vertical layouts, live response plots, title cards, editing, custom branding and audio are deferred. Encoding time varies by device and software/hardware codec. Compressed bytes and font/GPU rasterization can differ across machines; explicit timestamps and sampled engineering values remain deterministic. Downloads are buffered in memory; the duration limit bounds normal usage, not a guarantee against device memory exhaustion.
Mediabunny 1.56.2 provides browser-local encoding orchestration and container writing under MPL-2.0. Its unmodified source is available in the corresponding source package.