free space
Automated Generation of Continuous-Space Roadmaps for Routing Mobile Robot Fleets
Rüdt, Marvin, Enke, Constantin, Furmans, Kai
Efficient routing of mobile robot fleets is crucial in intralogistics, where delays and deadlocks can substantially reduce system throughput. Roadmap design, specifying feasible transport routes, directly affects fleet coordination and computational performance. Existing approaches are either grid-based, compromising geometric precision, or continuous-space approaches that disregard practical constraints. This paper presents an automated roadmap generation approach that bridges this gap by operating in continuous-space, integrating station-to-station transport demand and enforcing minimum distance constraints for nodes and edges. By combining free space discretization, transport demand-driven $K$-shortest-path optimization, and path smoothing, the approach produces roadmaps tailored to intralogistics applications. Evaluation across multiple intralogistics use cases demonstrates that the proposed approach consistently outperforms established baselines (4-connected grid, 8-connected grid, and random sampling), achieving lower structural complexity, higher redundancy, and near-optimal path lengths, enabling efficient and robust routing of mobile robot fleets.
- North America > United States > California > San Francisco County > San Francisco (0.14)
- Europe > Germany > Baden-Württemberg > Karlsruhe Region > Karlsruhe (0.05)
- North America > United States > Illinois > Cook County > Chicago (0.04)
- (12 more...)
Time-Optimized Safe Navigation in Unstructured Environments through Learning Based Depth Completion
Mao, Jeffrey, Srinivas, Raghuram Cauligi, Nogar, Steven, Loianno, Giuseppe
Quadrotors hold significant promise for several applications such as agriculture, search and rescue, and infrastructure inspection. Achieving autonomous operation requires systems to navigate safely through complex and unfamiliar environments. This level of autonomy is particularly challenging due to the complexity of such environments and the need for real-time decision making especially for platforms constrained by size, weight, and power (SWaP), which limits flight time and precludes the use of bulky sensors like Light Detection and Ranging (LiDAR) for mapping. Furthermore, computing globally optimal, collision-free paths and translating them into time-optimized, safe trajectories in real time adds significant computational complexity. To address these challenges, we present a fully onboard, real-time navigation system that relies solely on lightweight onboard sensors. Our system constructs a dense 3D map of the environment using a novel visual depth estimation approach that fuses stereo and monocular learning-based depth, yielding longer-range, denser, and less noisy depth maps than conventional stereo methods. Building on this map, we introduce a novel planning and trajectory generation framework capable of rapidly computing time-optimal global trajectories. As the map is incrementally updated with new depth information, our system continuously refines the trajectory to maintain safety and optimality. Both our planner and trajectory generator outperforms state-of-the-art methods in terms of computational efficiency and guarantee obstacle-free trajectories. We validate our system through robust autonomous flight experiments in diverse indoor and outdoor environments, demonstrating its effectiveness for safe navigation in previously unknown settings.
- North America > United States > California > Alameda County > Berkeley (0.14)
- North America > United States > New Jersey > Hudson County > Hoboken (0.04)
- Automobiles & Trucks (0.70)
- Transportation > Ground > Road (0.30)
- North America > United States > California (1.00)
- Europe (1.00)
- Information Technology > Artificial Intelligence > Robots > Robot Planning & Action (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Planning & Scheduling (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Search (0.93)
- Information Technology > Artificial Intelligence > Machine Learning > Neural Networks > Deep Learning (0.46)
- North America > United States > California (1.00)
- Europe (1.00)
- Government (0.46)
- Energy > Oil & Gas > Upstream (0.30)
- Information Technology > Artificial Intelligence > Robots > Robot Planning & Action (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Planning & Scheduling (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Search (0.93)
- (2 more...)
Real-Time Spatial Reasoning by Mobile Robots for Reconstruction and Navigation in Dynamic LiDAR Scenes
Huang, Pengdi, Wang, Mingyang, Tian, Huan, Gong, Minglun, Zhang, Hao, Huang, Hui
--Our brain has an inner global positioning system which enables us to sense and navigate 3D spaces in real time. Can mobile robots replicate such a biological feat in a dynamic environment? We introduce the first spatial reasoning framework for real-time surface reconstruction and navigation that is designed for outdoor LiDAR scanning data captured by ground mobile robots and capable of handling moving objects such as pedestrians. Our reconstruction-based approach is well aligned with the critical cellular functions performed by the border vector cells (BVCs) over all layers of the medial entorhinal cortex (MEC) for surface sensing and tracking. T o address the challenges arising from blurred boundaries resulting from sparse single-frame LiDAR points and outdated data due to object movements, we integrate real-time single-frame mesh reconstruction, via visibility reasoning, with robot navigation assistance through on-the-fly 3D free space determination. This enables continuous and incremental updates of the scene and free space across multiple frames. Key to our method is the utilization of line-of-sight (LoS) vectors from LiDAR, which enable real-time surface normal estimation, as well as robust and instantaneous per-voxel free space updates. Comprehensive experiments on both synthetic and real scenes highlight our method's superiority in speed and quality over existing real-time LiDAR processing approaches. UMANS and most animals all possess the innate ability to sense and navigate through spatial environments around them in real time. While the complete and precise mechanisms behind such capabilities are not yet fully understood, the Nobel-winning work conducted by John O'Keefe in the 1970s on place cells [1], [2] has paved the way for understanding the brain's "inner global positioning system (GPS)". Pengdi Huang, Mingyang Wang, Huan Tian, and Hui Huang are with College of Computer Science and Software Engineering, Shenzhen University, Shenzhen 518060, China (email: alualu628628@gmail.com; Minglun Gong is with School of Computer Science, University of Guelph, Delft N1G 2W1, Canada (email: minglun@uoguelph.ca) Hao Zhang is with School of Computing Science, Simon Fraser University, Burnaby V3J 1A1, Canada (email: haoz@sfu.ca)
- Asia > China > Guangdong Province > Shenzhen (0.44)
- North America > Canada (0.44)
- Europe > Netherlands > South Holland > Delft (0.24)
- Asia > Middle East > Republic of Türkiye > Karaman Province > Karaman (0.04)
- Energy (0.93)
- Health & Medicine > Therapeutic Area > Neurology (0.67)
Learning Orientation Field for OSM-Guided Autonomous Navigation
Huang, Yuming, Gao, Wei, Zhang, Zhiyuan, Ghaffari, Maani, Song, Dezhen, Xu, Cheng-Zhong, Kong, Hui
OpenStreetMap (OSM) has gained popularity recently in autonomous navigation due to its public accessibility, lower maintenance costs, and broader geographical coverage. However, existing methods often struggle with noisy OSM data and incomplete sensor observations, leading to inaccuracies in trajectory planning. These challenges are particularly evident in complex driving scenarios, such as at intersections or facing occlusions. To address these challenges, we propose a robust and explainable two-stage framework to learn an Orientation Field (OrField) for robot navigation by integrating LiDAR scans and OSM routes. In the first stage, we introduce the novel representation, OrField, which can provide orientations for each grid on the map, reasoning jointly from noisy LiDAR scans and OSM routes. To generate a robust OrField, we train a deep neural network by encoding a versatile initial OrField and output an optimized OrField. Based on OrField, we propose two trajectory planners for OSM-guided robot navigation, called Field-RRT* and Field-Bezier, respectively, in the second stage by improving the Rapidly Exploring Random Tree (RRT) algorithm and Bezier curve to estimate the trajectories. Thanks to the robustness of OrField which captures both global and local information, Field-RRT* and Field-Bezier can generate accurate and reliable trajectories even in challenging conditions. We validate our approach through experiments on the SemanticKITTI dataset and our own campus dataset. The results demonstrate the effectiveness of our method, achieving superior performance in complex and noisy conditions. Our code for network training and real-world deployment is available at https://github.com/IMRL/OriField.
- Asia > Singapore (0.04)
- Asia > Macao (0.04)
- North America > United States > Michigan > Washtenaw County > Ann Arbor (0.04)
- (3 more...)
Narrow Passage Path Planning using Collision Constraint Interpolation
Lee, Minji, Lee, Jeongmin, Lee, Dongjun
Narrow passage path planning is a prevalent problem from industrial to household sites, often facing difficulties in finding feasible paths or requiring excessive computational resources. Given that deep penetration into the environment can cause optimization failure, we propose a framework to ensure feasibility throughout the process using a series of subproblems tailored for narrow passage problem. We begin by decomposing the environment into convex objects and initializing collision constraints with a subset of these objects. By continuously interpolating the collision constraints through the process of sequentially introducing remaining objects, our proposed framework generates subproblems that guide the optimization toward solving the narrow passage problem. Several examples are presented to demonstrate how the proposed framework addresses narrow passage path planning problems.
FRTree Planner: Robot Navigation in Cluttered and Unknown Environments with Tree of Free Regions
Li, Yulin, Song, Zhicheng, Zheng, Chunxin, Bi, Zhihai, Chen, Kai, Wang, Michael Yu, Ma, Jun
In this work, we present FRTree planner, a novel robot navigation framework that leverages a tree structure of free regions, specifically designed for navigation in cluttered and unknown environments with narrow passages. The framework continuously incorporates real-time perceptive information to identify distinct navigation options and dynamically expands the tree toward explorable and traversable directions. This dynamically constructed tree incrementally encodes the geometric and topological information of the collision-free space, enabling efficient selection of the intermediate goals, navigating around dead-end situations, and avoidance of dynamic obstacles without a prior map. Crucially, our method performs a comprehensive analysis of the geometric relationship between free regions and the robot during online replanning. In particular, the planner assesses the accessibility of candidate passages based on the robot's geometries, facilitating the effective selection of the most viable intermediate goals through accessible narrow passages while minimizing unnecessary detours. By combining the free region information with a bi-level trajectory optimization tailored for robots with specific geometries, our approach generates robust and adaptable obstacle avoidance strategies in confined spaces. Through extensive simulations and real-world experiments, FRTree demonstrates its superiority over benchmark methods in generating safe, efficient motion plans through highly cluttered and unknown terrains with narrow gaps.
- Asia > China > Hong Kong (0.04)
- Asia > China > Guangdong Province > Guangzhou (0.04)
- Asia > Middle East > Republic of Türkiye > Karaman Province > Karaman (0.04)
- Africa > Togo (0.04)
ReFeree: Radar-Based Lightweight and Robust Localization using Feature and Free space
Kim, Hogyun, Choi, Byunghee, Choi, Euncheol, Cho, Younggun
Place recognition plays an important role in achieving robust long-term autonomy. Real-world robots face a wide range of weather conditions (e.g. overcast, heavy rain, and snowing) and most sensors (i.e. camera, LiDAR) essentially functioning within or near-visible electromagnetic waves are sensitive to adverse weather conditions, making reliable localization difficult. In contrast, radar is gaining traction due to long electromagnetic waves, which are less affected by environmental changes and weather independence. In this work, we propose a radar-based lightweight and robust place recognition. We achieve rotational invariance and lightweight by selecting a one-dimensional ring-shaped description and robustness by mitigating the impact of false detection utilizing opposite noise characteristics between free space and feature. In addition, the initial heading can be estimated, which can assist in building a SLAM pipeline that combines odometry and registration, which takes into account onboard computing. The proposed method was tested for rigorous validation across various scenarios (i.e. single session, multi-session, and different weather conditions). In particular, we validate our descriptor achieving reliable place recognition performance through the results of extreme environments that lacked structural information such as an OORD dataset.