Uploaded June 2021 | Updated September 2026, 3 weeks ago
This paper presents fast and informative local world representations for the safe navigation of legged robots during Visual Teach and Repeat (VT&R) missions. We show how meaningful representations can be computed from the local elevation map using simple image processing techniques, and its closed loop integration with a Riemannian Motion Policies-based twist controller. We demonstrate our approach with ANYmal C in a challenging indoor environment.
Accepted to the 5th Full-Day Workshop on Legged Robots at ICRA 2021
Authors: Matías Mattamala, Nived Chebrolu, Maurice Fallon
PDF: drive.google.com/file/d/1pYGr4q2F-uGriIovyVI859n7xHnoSCsc/view?usp=sharing
Presentation: youtu.be/Dvy6L799dn4
This paper presents fast and informative local world representations for the safe navigation of legged robots during Visual Teach and Repeat (VT&R) missions. We show how meaningful representations can be computed from the local elevation map using simple image processing techniques, and its closed loop integration with a Riemannian Motion Policies-based twist controller. We demonstrate our approach with ANYmal C in a challenging indoor environment.
Accepted to the 5th Full-Day Workshop on Legged Robots at ICRA 2021
Authors: Matías Mattamala, Nived Chebrolu, Maurice Fallon
PDF: drive.google.com/file/d/1pYGr4q2F-uGriIovyVI859n7xHnoSCsc/view?usp=sharing
Presentation: youtu.be/Dvy6L799dn4
![[Presentation] Elastic and Efficient LiDAR Reconstruction for Large-Scale Exploration Tasks
Video presentation of the article https://arxiv.org/abs/2010.09232
Elastic and Efficient LiDAR Reconstruction for Large-Scale Exploration Tasks
Yiduo Wang, Nils Funk, Milad Ramezani, Sotiris Papatheodorou, Marija Popovic, Marco Camurri, Stefan Leutenegger, Maurice Fallon
IEEE International Conference on Robotics and Automation (ICRA), 2021
Abstract:
We present an efficient, elastic 3D LiDAR reconstruction framework which can reconstruct up to maximum LiDAR ranges (60 m) at multiple frames per second, thus enabling robot exploration in large-scale environments. Our approach only requires a CPU. We focus on three main challenges of large-scale reconstruction: integration of long-range LiDAR scans at high frequency, the capacity to deform the reconstruction after loop closures are detected, and scalability for long-duration exploration. Our system extends upon a state-of-the-art efficient RGB-D volumetric reconstruction technique, called supereight, to support LiDAR scans and a newly developed submapping technique to allow for dynamic correction of the 3D reconstruction. We then introduce a novel pose graph clustering and submap fusion feature to make the proposed system more scalable for large environments. We evaluate the performance using two public datasets including outdoor exploration with a handheld device and a drone, and with a mobile robot exploring an underground room network. Experimental results demonstrate that our system can reconstruct at 3 Hz with 60 m sensor range and ~5 cm resolution, while state-of-the-art approaches can only reconstruct to 25 cm resolution or 20 m range at the same frequency. [Presentation] Elastic and Efficient LiDAR Reconstruction for Large-Scale Exploration Tasks](https://i.ytimg.com/vi/mNMdlNkWeVM/mqdefault.jpg)








![OASIS-Map: Object-Level Change Detection in Multi-Session Mapping using Semantic Correspondence
[Abstract]
Map representations which are consistent across repeated visits to a real-world semi-static environment are very useful for long-term robotic inspection. In such settings, the scene may evolve while the robot is absent, with objects appearing, disappearing, moving, or being replaced, quickly making a static map outdated. Existing change-detection methods reason through geometry, category-level semantics, or object persistence. However, achieving reliable object association across revisits remains a key challenge, especially under partial views, occlusion, and imperfect segmentation. In this work, we propose OASIS-Map, a multi-session mapping system that maintains a spatio-temporally consistent object-level map by establishing dense patch-level semantic correspondences between temporal observations. These correspondences detect where the scene has changed and incrementally associate objects across revisits as the robot re-observes the environment. We demonstrate OASIS-Map on three challenging real-world scenarios: object rearrangements in 3RScan, visually similar car replacements in a car park, and large-scale scene changes in an outdoor market. We achieve 0.783 F1 on change detection in a car replacement scenario in a car park and 0.667 F1 on moved object association in 3RScan. https://dynamic.robots.ox.ac.uk/projects/oasis-map/
Authors: Haedam Oh, Yifu Tao, Nived Chebrolu, and Maurice Fallon
Pre-print: https://arxiv.org/abs/2607.14899 OASIS-Map: Object-Level Change Detection in Multi-Session Mapping using Semantic Correspondence](https://i.ytimg.com/vi/sfVcFEXyTG4/mqdefault.jpg)
