Planning & Scheduling
CDFlow: Generative Gradient Flows for Configuration Space Distance Fields via Neural ODEs
Li, Mengzhu, Zhou, Yunyu, Ying, He, Yu, F. Richard
Signed Distance Fields (SDFs) are a fundamental representation in robot motion planning. Their configuration-space counterpart, the Configuration Space Distance Field (CDF), directly encodes distances in joint space, offering a unified representation for optimization and control. However, existing CDF formulations face two major challenges in high-degree-of-freedom (DoF) robots: (1) they effectively return only a single nearest collision configuration, neglecting the multi-modal nature of minimal-distance collision configurations and leading to gradient ambiguity; and (2) they rely on sparse sampling of the collision boundary, which often fails to identify the true closest configurations, producing oversmoothed approximations and geometric distortion in high-dimensional spaces. We propose CDFlow, a novel framework that addresses these limitations by learning a continuous flow in configuration space via Neural Ordinary Differential Equations (Neural ODEs). We redefine the problem from finding a single nearest point to modeling the distribution of minimal-distance collision configurations. We also introduce an adaptive refinement sampling strategy to generate high-fidelity training data for this distribution. The resulting Neural ODE implicitly models this multi-modal distribution and produces a smooth, consistent gradient field-derived as the expected direction towards the distribution-that mitigates gradient ambiguity and preserves sharp geometric features. Extensive experiments on high-DoF motion planning tasks demonstrate that CDFlow significantly improves planning efficiency, trajectory quality, and robustness compared to existing CDF-based methods, enabling more robust and efficient planning for collision-aware robots in complex environments.
SPAR: Scalable LLM-based PDDL Domain Generation for Aerial Robotics
Huang, Songhao, Wu, Yuwei, Shi, Guangyao, Sukhatme, Gaurav S., Kumar, Vijay
We investigate the problem of automatic domain generation for the Planning Domain Definition Language (PDDL) using Large Language Models (LLMs), with a particular focus on unmanned aerial vehicle (UAV) tasks. Although PDDL is a widely adopted standard in robotic planning, manually designing domains for diverse applications such as surveillance, delivery, and inspection is labor-intensive and error-prone, which hinders adoption and real-world deployment. To address these challenges, we propose SPAR, a framework that leverages the generative capabilities of LLMs to automatically produce valid, diverse, and semantically accurate PDDL domains from natural language input. To this end, we first introduce a systematically formulated and validated UAV planning dataset, consisting of ground-truth PDDL domains and associated problems, each paired with detailed domain and action descriptions. Building on this dataset, we design a prompting framework that generates high-quality PDDL domains from language input. The generated domains are evaluated through syntax validation, executability, feasibility, and interpretability. Overall, this work demonstrates that LLMs can substantially accelerate the creation of complex planning domains, providing a reproducible dataset and evaluation pipeline that enables application experts without prior experience to leverage it for practical tasks and advance future research in aerial robotics and automated planning.
Keypoint-based Diffusion for Robotic Motion Planning on the NICOL Robot
Clasmeier, Lennart, Habekost, Jan-Gerrit, Gรคde, Connor, Allgeuer, Philipp, Wermter, Stefan
We propose a novel diffusion-based action model for robotic motion planning. Commonly, established numerical planning approaches are used to solve general motion planning problems, but have significant runtime requirements. By leveraging the power of deep learning, we are able to achieve good results in a much smaller runtime by learning from a dataset generated by these planners. While our initial model uses point cloud embeddings in the input to predict keypoint-based joint sequences in its output, we observed in our ablation study that it remained challenging to condition the network on the point cloud embeddings. We identified some biases in our dataset and refined it, which improved the model's performance. Our model, even without the use of the point cloud encodings, outperforms numerical models by an order of magnitude regarding the runtime, while reaching a success rate of up to 90% of collision free solutions on the test set.
Bridging Engineering and AI Planning through Model-Based Knowledge Transformation for the Validation of Automated Production System Variants
Nabizada, Hamied, Beers, Lasse, Chahine, Alain, Gehlhoff, Felix, Niggemann, Oliver, Fay, Alexander
Engineering models created in Model-Based Systems Engineering (MBSE) environments contain detailed information about system structure and behavior. However, they typically lack symbolic planning semantics such as preconditions, effects, and constraints related to resource availability and timing. This limits their ability to evaluate whether a given system variant can fulfill specific tasks and how efficiently it performs compared to alternatives. To address this gap, this paper presents a model-driven method that enables the specification and automated generation of symbolic planning artifacts within SysML-based engineering models. A dedicated SysML profile introduces reusable stereotypes for core planning constructs. These are integrated into existing model structures and processed by an algorithm that generates a valid domain file and a corresponding problem file in Planning Domain Definition Language (PDDL). In contrast to previous approaches that rely on manual transformations or external capability models, the method supports native integration and maintains consistency between engineering and planning artifacts. The applicability of the method is demonstrated through a case study from aircraft assembly. The example illustrates how existing engineering models are enriched with planning semantics and how the proposed workflow is applied to generate consistent planning artifacts from these models. The generated planning artifacts enable the validation of system variants through AI planning.
UniPilot: Enabling GPS-Denied Autonomy Across Embodiments
Kulkarni, Mihir, Dharmadhikari, Mihir, Khedekar, Nikhil, Nissov, Morten, Singh, Mohit, Weiss, Philipp, Alexis, Kostas
Exploded view of the UniPilot module, with hardware, sensing, and compute components highlighted, alongside an image of the aerial platform that integrates the module in a process tank environment. Abstract-- This paper presents UniPilot, a compact hardware-software autonomy payload that can be integrated across diverse robot embodiments to enable autonomous operation in GPS-denied environments. The system integrates a multi-modal sensing suite including LiDAR, radar, vision, and inertial sensing for robust operation in conditions where uni-modal approaches may fail. UniPilot runs a complete autonomy software comprising multi-modal perception, exploration and inspection path planning, and learning-based navigation policies. The payload provides robust localization, mapping, planning, and safety and control capabilities in a single unit that can be deployed across a wide range of platforms. A large number of experiments are conducted across diverse environments and on a variety of robot platforms to validate the mapping, planning, and safe navigation capabilities enabled by the payload. I. INTRODUCTION With the progressing rise of autonomy, it becomes increasingly more important to be able to test a wide variety of complex methods and systems on easily re-creatable platforms. Especially of interest is to investigate and demonstrate a method's generality across different robot embodiments. Furthermore, the demand for autonomy in different robot actualization and in varied environments necessitates flexibility at the core of this design philosophy.
PaiP: An Operational Aware Interactive Planner for Unknown Cabinet Environments
Wang, Chengjin, Yan, Zheng, Zhou, Yanmin, Shen, Runjie, Wang, Zhipeng, Cheng, Bin, He, Bin
Box/cabinet scenarios with stacked objects pose significant challenges for robotic motion due to visual occlusions and constrained free space. Traditional collision-free trajectory planning methods often fail when no collision-free paths exist, and may even lead to catastrophic collisions caused by invisible objects. To overcome these challenges, we propose an operational aware interactive motion planner (PaiP) a real-time closed-loop planning framework utilizing multimodal tactile perception. This framework autonomously infers object interaction features by perceiving motion effects at interaction interfaces. These interaction features are incorporated into grid maps to generate operational cost maps. Building upon this representation, we extend sampling-based planning methods to interactive planning by optimizing both path cost and operational cost. Experimental results demonstrate that PaiP achieves robust motion in narrow spaces.
A Holistic Architecture for Monitoring and Optimization of Robust Multi-Agent Path Finding Plan Execution
Zahrรกdka, David, Muลพรญkovรก, Denisa, Woller, David, Kulich, Miroslav, ล vancara, Jiลรญ, Bartรกk, Roman
The goal of Multi-Agent Path Finding (MAPF) is to find a set of paths for a fleet of agents moving in a shared environment such that the agents reach their goals without colliding with each other. In practice, some of the robots executing the plan may get delayed, which can introduce collision risk. Although robust execution methods are used to ensure safety even in the presence of delays, the delays may still have a significant impact on the duration of the execution. At some point, the accumulated delays may become significant enough that instead of continuing with the execution of the original plan, even if it was optimal, there may now exist an alternate plan which will lead to a shorter execution. However, the problem is how to decide when to search for the alternate plan, since it is a costly procedure. In this paper, we propose a holistic architecture for robust execution of MAPF plans, its monitoring and optimization. We exploit a robust execution method called Action Dependency Graph to maintain an estimate of the expected execution duration during the plan's execution. This estimate is used to predict the potential that finding an alternate plan would lead to shorter execution. We empirically evaluate the architecture in experiments in a real-time simulator which we designed to mimic our real-life demonstrator of an autonomous warehouse robotic fleet.
Multi-Robot Navigation in Social Mini-Games: Definitions, Taxonomy, and Algorithms
Chandra, Rohan, Singh, Shubham, Luo, Wenhao, Sycara, Katia
The ``Last Mile Challenge'' has long been considered an important, yet unsolved, challenge for autonomous vehicles, public service robots, and delivery robots. A central issue in this challenge is the ability of robots to navigate constrained and cluttered environments that have high agency (e.g., doorways, hallways, corridor intersections), often while competing for space with other robots and humans. We refer to these environments as ``Social Mini-Games'' (SMGs). Traditional navigation approaches designed for MRN do not perform well in SMGs, which has led to focused research on dedicated SMG solvers. However, publications on SMG navigation research make different assumptions (on centralized versus decentralized, observability, communication, cooperation, etc.), and have different objective functions (safety versus liveness). These assumptions and objectives are sometimes implicitly assumed or described informally. This makes it difficult to establish appropriate baselines for comparison in research papers, as well as making it difficult for practitioners to find the papers relevant to their concrete application. Such ad-hoc representation of the field also presents a barrier to new researchers wanting to start research in this area. SMG navigation research requires its own taxonomy, definitions, and evaluation protocols to guide effective research moving forward. This survey is the first to catalog SMG solvers using a well-defined and unified taxonomy and to classify existing methods accordingly. It also discusses the essential properties of SMG solvers, defines what SMGs are and how they appear in practice, outlines how to evaluate SMG solvers, and highlights the differences between SMG solvers and general navigation systems. The survey concludes with an overview of future directions and open challenges in the field. Our project is open-sourced at https://socialminigames.github.io/.
Parallel, Asymptotically Optimal Algorithms for Moving Target Traveling Salesman Problems
Bhat, Anoop, Gutow, Geordan, Vundurthy, Bhaskar, Ren, Zhongqiang, Rathinam, Sivakumar, Choset, Howie
Abstract--The Moving T arget Traveling Salesman Problem (MT -TSP) seeks an agent trajectory that intercepts several moving targets, within a particular time window for each target. Therefore, we introduce the Iterated Random Generalized (IRG) TSP framework. The key idea behind IRG is to alternate between randomly sampling a set of agent configuration-time points, corresponding to interceptions of targets, and finding a sequence of interception points by solving a generalized TSP (GTSP). This alternation enables asymptotic convergence to the optimum. We introduce two parallel algorithms within the IRG framework. The first algorithm, IRG-PGLNS, solves GTSPs using PGLNS, our parallelized extension of the state-of-the-art solver GLNS. The second algorithm, Parallel Communicating GTSPs (PCG), solves GTSPs corresponding to several sets of points simultaneously. We present numerical results for three variants of the MT -TSP: one where intercepting a target only requires coming within a particular distance, another where the agent is a variable-speed Dubins car, and a third where the agent is a redundant robot arm. We show that IRG-PGLNS and PCG both converge faster than a baseline based on prior work. The Traveling Salesman Problem (TSP) is a classic optimization problem with broad applications in various fields, including logistics, manufacturing, and robotics [1], [2]. Given a set of targets (often called "locations" or "cities") and the cost of travel between each target pair, the TSP seeks a minimum-cost order of targets for an agent to visit. However, several robotic applications require planning to visit moving targets: midair refueling [3], optimization of fishing routes [4], [5], resupplying ships at sea [6], surveillance [7]-[9], and intercepting dangerous projectiles [10]-[12]. In all subfigures, targets (stars) move along trajectories with time windows shown in bold colored lines.
Collaborative Exploration with a Marsupial Ground-Aerial Robot Team through Task-Driven Map Compression
Zacharia, Angelos, Dharmadhikari, Mihir, Alexis, Kostas
Abstract--Efficient exploration of unknown environments is crucial for autonomous robots, especially in confined and large-scale scenarios with limited communication. T o address this challenge, we propose a collaborative exploration framework for a marsupial ground-aerial robot team that leverages the complementary capabilities of both platforms. The framework employs a graph-based path planning algorithm to guide exploration and deploy the aerial robot in areas where its expected gain significantly exceeds that of the ground robot, such as large open spaces or regions inaccessible to the ground platform, thereby maximizing coverage and efficiency. T o facilitate large-scale spatial information sharing, we introduce a bandwidth-efficient, task-driven map compression strategy. This method enables each robot to reconstruct resolution-specific volumetric maps while preserving exploration-critical details, even at high compression rates. By selectively compressing and sharing key data, communication overhead is minimized, ensuring effective map integration for collaborative path planning. Simulation and real-world experiments validate the proposed approach, demonstrating its effectiveness in improving exploration efficiency while significantly reducing data transmission.