TRACE: Ergodic Trajectory Optimization for Active Scene Reconstruction
- On all eight Replica scenes, it achieves higher PSNR than ActiveGS, with an average gain of 1.5 dB. The image-quality metrics LPIPS and SSIM move in the same direction.
- The gains differ by scene type. In office scenes, SSIM is similar but LPIPS improves by 6% to 19%, while in room and hotel scenes the SSIM gap widens from 0.012 to 0.017.
- The gain does not come simply from taking more observation frames. A variant that added 10 random shots on the ActiveGS path matched the original within 0.08 dB, while a variant with 10 evenly interpolated shots was actually 1.7 dB worse.
- If the footstep-depletion trick is removed and only the original kernel ergodic objective is used, performance drops by 2.1 dB and becomes worse than ActiveGS on 6 of the 8 scenes. This shows that suppressing redundant observations is the key.
- On a Unitree Go2 quadruped robot with an Intel D435 RGB-D camera, the system was run on a 42-square-meter space for a 5-minute mission, and it executed without infeasible commands at the planned horizons.
- The real-world execution success rate was 100%, while the compared NBV baselines lightly touched the environment in every attempt. Because the trajectory itself is the optimization variable, waypoints can be passed directly to the controller.