Rig-Aware 3D Reconstruction of Vehicle Undercarriages using Gaussian Splatting
This addresses a domain-specific problem for vehicle inspectors and online buyers by improving workplace safety and buyer confidence, though it is incremental in applying existing 3D reconstruction techniques to a new application.
The paper tackles the labor-intensive inspection of vehicle undercarriages by developing an end-to-end pipeline using a three-camera rig to capture videos and produce interactive 3D models, enabling inspectors and customers to detect issues like rust or leaks in seconds, with experiments showing state-of-the-art quality.
Inspecting the undercarriage of used vehicles is a labor-intensive task that requires inspectors to crouch or crawl underneath each vehicle to thoroughly examine it. Additionally, online buyers rarely see undercarriage photos. We present an end-to-end pipeline that utilizes a three-camera rig to capture videos of the undercarriage as the vehicle drives over it, and produces an interactive 3D model of the undercarriage. The 3D model enables inspectors and customers to rotate, zoom, and slice through the undercarriage, allowing them to detect rust, leaks, or impact damage in seconds, thereby improving both workplace safety and buyer confidence. Our primary contribution is a rig-aware Structure-from-Motion (SfM) pipeline specifically designed to overcome the challenges of wide-angle lens distortion and low-parallax scenes. Our method overcomes the challenges of wide-angle lens distortion and low-parallax scenes by integrating precise camera calibration, synchronized video streams, and strong geometric priors from the camera rig. We use a constrained matching strategy with learned components, the DISK feature extractor, and the attention-based LightGlue matcher to generate high-quality sparse point clouds that are often unattainable with standard SfM pipelines. These point clouds seed the Gaussian splatting process to generate photorealistic undercarriage models that render in real-time. Our experiments and ablation studies demonstrate that our design choices are essential to achieve state-of-the-art quality.