Splat-Nav Logo

Safe Real-Time Robot Navigation in Gaussian Splatting Maps

*The co-first authors contributed equally.
1Stanford University, 2University of California San Diego, 3Temple University
Splat-Nav architecture.

Splat-Nav leverages GSplat models to plan safe trajectories in real-time. Splat-Nav consists of two components: (1) Splat-Plan, a safe planning module and (2) Splat-Loc, a robust vision-based pose estimation module. Leveraging rapid collision-checking routines made possible with GSplats, we demonstrate autonomous real-time flight in cluttered environments.

Abstract

We present Splat-Nav, a real-time robot navigation pipeline designed to work with environment representations generated by Gaussian Splatting (GSplat), a powerful new 3D scene representation. Splat-Nav consists of two components: 1) Splat-Plan, a safe planning module, and 2) Splat-Loc, a robust vision-based pose estimation module. Splat-Plan builds a safe-by-construction polytope corridor through the map based on mathematically rigorous collision constraints and then constructs a Bézier curve trajectory through this corridor. Splat-Loc provides real-time recursive state estimates given only an RGB feed from an on-board camera, leveraging the point-cloud representation inherent in GSplat scenes. Splat-Nav endows robots the ability to recursively re-plan smooth and safe trajectories to goal locations. Goal locations can be specified with position coordinates, or with language commands by using a language embedded GSplat. We demonstrate the safety and robustness of our pipeline in both simulation and hardware experiments, where we show online re-planning at more than 2 Hz and pose estimation at about 25 Hz, an order of magnitude faster than Neural Radiance Field (NeRF)-based navigation methods, thereby enabling real-time navigation.

Hardware Experiments

Four objects within the scene (beachball, keyboard, microwave, phonebook) are semnatically segmented and chosen as goal locations for our trials. We run using three control schemes (Open-Loop, Closed-Loop VIO, and Splat-Loc) each demonstrated in the videos below. We refer readers to our paper.


Open-Loop

Open-loop schemes do not re-plan, relying on the onboard VIO to track the trajectory.

Closed-Loop VIO

Closed-loop uses VIO to estimate poses and re-plan accordingly.

Splat-Loc

Splat-Loc estimates the current drone pose and re-plans a path to the goal location. This method is robust against disturbance and drift.

Faster Drone Flights

We also demonstrate the robustness of Splat-Plan by tracking open-loop trajectories at 1.5 m/s.

Endurance Flights

Finally, closed-loop re-planning using Splat-Plan and Splat-Loc can safely navigate cluttered environments over long periods of time.

BibTeX


      @misc{chen2024splatnav,
        title={Splat-Nav: Safe Real-Time Robot Navigation in Gaussian Splatting Maps}, 
        author={Timothy Chen and Ola Shorinwa and Joseph Bruno and Aiden Swann and Javier Yu and Weijia Zeng and Keiko Nagami and Philip Dames and Mac Schwager},
        year={2024},
        eprint={2403.02751},
        archivePrefix={arXiv},
        primaryClass={cs.RO},
        url={https://arxiv.org/abs/2403.02751}, 
      }