Real drive → simulationProgress

From one real drive to a simulation world you can vary.

We turn a recorded drive, multi-camera video plus LiDAR, into a simulation-ready, labelled OpenUSD scene: the street as a 3D Gaussian-splat background, the traffic regenerated and driven back along its LiDAR tracks. The same drive then comes back in rain, dust, dusk or night, or with a pothole that a simulated vehicle drives over.

The pipeline is not tied to one country: it has run unchanged on US city, US freeway and European clips. The reference clip shown here is a US intersection.

Every step below ran end to end on that clip, and every number in the steps comes straight from that run's own record.

Real camera
Reconstructed · Full NuRec

Front camera, same moment and pose: the real recording and the reconstructed scene. Masked PSNR 17.8 dB, scored on the 76% of the frame the render draws.

What you get from one drive

Each step shows real output from the reference drive and one number from its run.

01
live

Multi-camera + LiDAR footage in

A recorded drive with surround cameras and a roof LiDAR, converted to NVIDIA's NCore format. The reconstruction is rendered and scored against the real footage on 6 cameras.

20 s
of driving in the reference clip
02
live

A 3D Gaussian-splat background of the street

The static street, reconstructed as 3D Gaussian splats with NVIDIA's NuRec after the tracked vehicles are masked out: 2.7 million Gaussians. Shown here from a side camera; the front camera is at the top of the page.

22.3 dB
masked PSNR, cross right 120° camera, on the 76% of the frame the render draws
Real camera
Reconstructed · Full NuRec
03
live

The real vehicles, regenerated and driven back along their LiDAR tracks

These are generated look-alikes, not reconstructions. NVIDIA's Asset Harvester generates each vehicle from a few camera crops; it is sized to its LiDAR box, drives its recorded track and is visible only while it was observed. Shape and colour can differ from the real car.

16
vehicles placed back in this scene
real camera crop of ext_0006generated vehicle ext_0006real crop · generated
real camera crop of ext_0009generated vehicle ext_0009real crop · generated
real camera crop of ext_0002generated vehicle ext_0002real crop · generated
real camera crop of ext_0000generated vehicle ext_0000real crop · generated
real camera crop of ext_0004generated vehicle ext_0004real crop · generated
real camera crop of ext_0026generated vehicle ext_0026real crop · generated
Left of each pair: a crop from the real camera. Right: the vehicle generated from such crops. 6 of 16 shown.
04
live

One OpenUSD scene that opens in Isaac Sim

The background and all 16 vehicles in one OpenUSD file. It passes OpenUSD's own validators, and it opens and plays in Isaac Sim.

0 issues
from 30 OpenUSD validators
05
live

Variations of the same drive: rain, dust, dusk, night

Procedural weather and light, applied to the rendered scene (rendered effects, not a generative model). The scene's labels stay byte-identical to the base scene's, and each variant must pass a flicker check before it is shown. Each video: the plain render on the left, the variant on the right.

4 of 4
variants with labels byte-identical to the base scene
heavy rain
dust haze
dusk
night with headlights
06
live

A pothole carved into road and splats, driven over with vehicle physics

A 1.2 × 0.9 m pothole, 12 cm deep, is cut into the LiDAR ground mesh and into the splat road. A simulated vehicle (MuJoCo) drives over it at 28 km/h, and its body motion moves the dashcam. The plot shows the body's height, pitch and roll over time.

3.5 cm
body dip over the pothole, 1.0° peak pitch
pothole with vehicle physics
Vehicle body motion over the pothole: ride height, pitch and roll against time
Vehicle body motion over the pothole

What is not right yet

One reference clip is proven end to end. On three more clips the pipeline ran unchanged but the variations were blocked: on two, the reconstructed road sat 17 to 19 cm below the LiDAR ground mesh; on a freeway clip, the pothole cannot be placed at highway speed and rain failed its flicker check.
Cars that were cut out of the background but not regenerated leave dark, car-shaped holes in the street.
The generated cars are look-alikes: the right size and path, but shape and colour can differ from the real car, and a few are poor.
No pedestrians or two-wheelers in the scenes yet. Pedestrians stay baked into the background; no real two-wheeler has reached a scene.
The fully trained background has artifacts low on the road just past the hood (an orange blob, thin blue streaks). On it, pothole + heavy rain failed its flicker check; that variant appears only in the technical appendix, marked FAILED.
The pothole is realistic for its size, so the body dip is small and hard to see from the dashcam.

Milestones

  1. 2026-09-18

    One command from a raw drive to a validated OpenUSD scene

    Every stage ran on real data in a single pipeline run.

  2. 2026-10-11

    A fully trained background

    A 40,000-step NuRec training background composed with the vehicles, and the first frame-by-frame review of renders against the real cameras.

  3. 2026-10-28

    Vehicles checked against the real cameras

    Placed vehicles face their direction of travel and appear only while they were observed. Scores count only the pixels the render draws, with that coverage shown next to them.

  4. 2026-10-29

    Variations with physics

    Rain, dust, dusk and night applied to the reconstructed drive with its labels unchanged; a ground mesh from the accumulated LiDAR that agrees with the reconstructed road to 2.7 cm (median); a pothole carved into mesh and scene and driven over by a simulated vehicle whose body motion moves the camera, also in Isaac Sim. See the run.

  5. 2026-10-30

    Rebuilt from code on a fresh cloud GPU and reproduced the result

    A new cloud GPU machine was set up from the repository alone in about 17 minutes and ran the clip: the same ground mesh, pothole and physics numbers, and front-camera masked PSNR 19.39 dB against 19.42 dB before. See the run.

  6. 2026-10-31

    Variations on the fully trained background

    The variation stages ran on the 40,000-step background too: road agreement with the LiDAR ground mesh 1.1 mm (median), pothole footprint IoU 0.935, the same physics as on the fast background. See the run.

Technical appendix

The full review of each clip: both reconstruction modes side by side, every camera, how every score is computed, and earlier runs. Large 3D files (OpenUSD scenes, splat PLYs) are not hosted here; they are shared on request.

US intersection, about 20 s 9fc15f8c

One clip from NVIDIA's PhysicalAI Autonomous Vehicles dataset: 7 cameras and a roof LiDAR, driving through an intersection.

Full review → Instant NuRec and Full NuRec: every camera, every metric with its coverage, every variation (failed ones marked).

Earlier runs: 2026-10-30 10:27 UTC (Instant NuRec), 2026-10-29 14:40 UTC (Instant NuRec), 2026-10-29 09:41 UTC (Instant NuRec).