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Yang, C., Wang, R., Jiang, J., Jiang, Q., Zhang, Q., Deng, Y., . . . Wang, X. (2026). Nondeterministic Polynomial-time Problem Challenge: An Ever-Scaling Reasoning Benchmark for LLMs. Transactions on Machine Learning Research, 2026-February
Open this publication in new window or tab >>Nondeterministic Polynomial-time Problem Challenge: An Ever-Scaling Reasoning Benchmark for LLMs
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2026 (English)In: Transactions on Machine Learning Research, E-ISSN 2835-8856, Vol. 2026-FebruaryArticle in journal (Refereed) Published
Abstract [en]

Reasoning is the fundamental capability of large language models (LLMs). Due to the rapid progress of LLMs, there are two main issues of current benchmarks: i) these benchmarks can be crushed in a short time (less than 1 year), and ii) these benchmarks may be easily hacked. To handle these issues, we propose the ever-scalingness for building the benchmarks which are scaling over complexity against crushing, instance against hacking and exploitation, oversight for easy verification, and coverage for real-world relevance. This paper presents Nondeterministic Polynomial-time Problem Challenge (NPPC), an ever-scaling reasoning benchmark for LLMs. Specifically, the NPPC has three main modules: i) npgym, which provides a unified interface of 25 well-known NP-complete problems and can generate any number of instances with any levels of complexities, ii) npsolver, which provides a unified interface to evaluate the problem instances with both online and offline models via APIs and local deployments, respectively, and iii) npeval, which provides the comprehensive and readyto-use tools to analyze the performances of LLMs over different problems, the number of tokens, the reasoning errors and the solution errors. Extensive experiments over widely-used LLMs demonstrate: i) NPPC can successfully decrease the performances of advanced LLMs to below 10%, demonstrating that NPPC is not crushed by current models, ii) DeepSeek-R1, Claude-3.7-Sonnet, and o1/o3-mini are the most powerful LLMs, where DeepSeek-R1 can outperform Claude-3.7-Sonnet and o1/o3-mini in most NP-complete problems considered, and iii) the numbers of tokens in the advanced LLMs, e.g., Claude-3.7-Sonnet and DeepSeekR1, are observed first to increase and then decrease when the problem instances become more and more difficult. Through continuously scaling analysis, NPPC can provide critical insights into the limits of LLMs’ reasoning capabilities, exposing fundamental limitations and suggesting future directions for further improvements.

Place, publisher, year, edition, pages
Transactions on Machine Learning Research, 2026
National Category
Computer Sciences Software Engineering
Identifiers
urn:nbn:se:kth:diva-377463 (URN)2-s2.0-105029743616 (Scopus ID)
Note

QC 20260302

Available from: 2026-03-02 Created: 2026-03-02 Last updated: 2026-03-02Bibliographically approved
Wang, R., Zhuang, Z., Kragic Jensfelt, D. & Pokorny, F. T. (2026). PALM: Enhanced Generalizability for Local Visuomotor Policies Via Perception Alignment. IEEE Robotics and Automation Letters, 11(4), 4865-4872
Open this publication in new window or tab >>PALM: Enhanced Generalizability for Local Visuomotor Policies Via Perception Alignment
2026 (English)In: IEEE Robotics and Automation Letters, E-ISSN 2377-3766, Vol. 11, no 4, p. 4865-4872Article in journal (Refereed) Published
Abstract [en]

Generalizing beyond the training domain in image-based behavior cloning remains challenging. Existing methods address individual axes of generalization, workspace shifts, viewpoint changes, and cross-embodiment transfer, yet they are typically developed in isolation and often rely on complex pipelines. We introduce PALM (Perception Alignment for Local Manipulation), which leverages the invariance of local action distributions between out-of-distribution (OOD) and demonstrated domains to address these OOD shifts concurrently, without additional input modalities, model changes, or data collection. PALM modularizes the manipulation policy into coarse global components and a local policy for fine-grained actions. We reduce the discrepancy between in-domain and OOD inputs at the local policy level by enforcing local visual focus and consistent proprioceptive representation, allowing the policy to retrieve invariant local actions under OOD conditions. Experiments show that PALM limits OOD performance drops to 8% in simulation and 24% in the real world, compared to 45% and 77% for baselines.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2026
Keywords
Generalization, Imitation learning, Robotic Manipulation
National Category
Computer Sciences
Identifiers
urn:nbn:se:kth:diva-377622 (URN)10.1109/LRA.2026.3664620 (DOI)001708143000008 ()2-s2.0-105030180693 (Scopus ID)
Note

QC 20260305

Available from: 2026-03-05 Created: 2026-03-05 Last updated: 2026-05-29Bibliographically approved
Jin, S., Wang, R. & Pokorny, F. T. (2026). RealCraft: Attention Control as A Tool for Zero-Shot Consistent Video Editing. In: Neural Information Processing - 32nd International Conference, ICONIP 2025, Proceedings: . Paper presented at 32nd International Conference on Neural Information Processing, ICONIP 2025, Okinawa, Japan, November 20-24, 2025 (pp. 137-152). Springer Nature
Open this publication in new window or tab >>RealCraft: Attention Control as A Tool for Zero-Shot Consistent Video Editing
2026 (English)In: Neural Information Processing - 32nd International Conference, ICONIP 2025, Proceedings, Springer Nature , 2026, p. 137-152Conference paper, Published paper (Refereed)
Abstract [en]

Compared to text-driven diffusion-model-based image generation, editing is challenging due to the necessity for localized modifications. The complexity is further amplified for videos due to the additional requirement for temporal consistency. These challenges are highlighted when editing real-world videos, which, unlike synthetic videos, often feature factors like moving camera views and occlusions. In this paper, we propose RealCraft, an attention-control-based method for zero-shot real-world video editing. By swapping cross-attention in order to inject new features during the editing process and to relax the spatial-temporal attention of the edited object, we achieve localized shape-wise edits along with enhanced temporal consistency. Our model directly uses Stable Diffusion and operates without the need for additional networks or parameters. We showcase the proposed zero-shot attention-control-based method across a range of videos, demonstrating shape-wise, time-consistent and parameter-free editing in videos of up to 64 frames.

Place, publisher, year, edition, pages
Springer Nature, 2026
Keywords
Text-guided video editing, Zero-shot
National Category
Computer graphics and computer vision Probability Theory and Statistics
Identifiers
urn:nbn:se:kth:diva-373855 (URN)10.1007/978-981-95-4378-6_10 (DOI)001719849900010 ()2-s2.0-105022815736 (Scopus ID)
Conference
32nd International Conference on Neural Information Processing, ICONIP 2025, Okinawa, Japan, November 20-24, 2025
Note

Part of ISBN 9789819543779

QC 20251215

Available from: 2025-12-15 Created: 2025-12-15 Last updated: 2026-05-29Bibliographically approved
Cabral Muchacho, R. I., Laha, R., Pokorny, F. T., Figueredo, L. F. .. & Chakraborty, N. (2026). Unifying Complementarity Constraints and Control Barrier Functions for Safe Whole-Body Robot Control. IEEE Transactions on Automatic Control
Open this publication in new window or tab >>Unifying Complementarity Constraints and Control Barrier Functions for Safe Whole-Body Robot Control
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2026 (English)In: IEEE Transactions on Automatic Control, ISSN 0018-9286, E-ISSN 1558-2523Article in journal (Refereed) Epub ahead of print
Abstract [en]

Safety-critical whole-body robot control demands reactive methods that ensure collision avoidance in real-time. Complementarity constraints and control barrier functions (CBF) have emerged as core tools for ensuring such safety constraints, and each represents a well-developed field. Despite addressing similar problems, their connection remains largely unexplored. This paper bridges this gap by formally proving the equivalence between these two methodologies for sampled-data, first-order systems, considering both single and multiple constraint scenarios. By demonstrating this equivalence, we provide a unified perspective on these techniques. This unification has theoretical and practical implications, facilitating the cross-application of robustness guarantees and algorithmic improvements between complementarity and CBF frameworks. We discuss these synergistic benefits and motivate future work in the comparison of the methods in more general cases.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2026
Keywords
Autonomous Robots, Constrained control, Optimal control, Robotics
National Category
Robotics and automation Control Engineering
Identifiers
urn:nbn:se:kth:diva-386919 (URN)10.1109/TAC.2026.3716907 (DOI)2-s2.0-105045985468 (Scopus ID)
Note

QC 20260811

Available from: 2026-08-11 Created: 2026-08-11 Last updated: 2026-08-11Bibliographically approved
Cabral Muchacho, R. I. & Pokorny, F. T. (2025). Adaptive Distance Functions via Kelvin Transformation. In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025: . Paper presented at 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025 (pp. 3015-3021). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Adaptive Distance Functions via Kelvin Transformation
2025 (English)In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Institute of Electrical and Electronics Engineers (IEEE) , 2025, p. 3015-3021Conference paper, Published paper (Refereed)
Abstract [en]

The term safety in robotics is often understood as a synonym for avoidance. Although this perspective has led to progress in path planning and reactive control, a generalization of this perspective is necessary to include task semantics relevant to contact-rich manipulation tasks, especially during teleoperation and to ensure the safety of learned policies. We introduce the semantics-aware distance function and a corresponding computational method based on the Kelvin Transformation. This allows us to compute smooth distance approximations in an unbounded domain by instead solving a Laplace equation in a bounded domain. The semantics-aware distance generalizes signed distance functions by allowing the zero level set to lie inside of the object in regions where contact is allowed, effectively incorporating task semantics, such as object affordances, in an adaptive implicit representation of safe sets. In numerical experiments we show the computational viability of our method for real applications and visualize the computed function on a wrench with various semantic regions.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
National Category
Robotics and automation Computer graphics and computer vision
Identifiers
urn:nbn:se:kth:diva-371370 (URN)10.1109/ICRA55743.2025.11128013 (DOI)001582497400269 ()2-s2.0-105016634410 (Scopus ID)
Conference
2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025
Note

Part of ISBN 9798331541392

QC 20251013

Available from: 2025-10-13 Created: 2025-10-13 Last updated: 2026-05-29Bibliographically approved
Dong, Y., Han, S., Cheng, X., Friedl, W., Cabral Muchacho, R. I., Roa, M. A., . . . Pokorny, F. T. (2025). CageCoOpt: Enhancing Manipulation Robustness through Caging-Guided Morphology and Policy Co-Optimization. In: IROS 2025 - 2025 IEEE/RSJ International Conference on Intelligent Robots and Systems, Conference Proceedings: . Paper presented at 2025 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2025, Oct 19 2025 - Oct 25 2025, Hangzhou, China (pp. 21795-21802). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>CageCoOpt: Enhancing Manipulation Robustness through Caging-Guided Morphology and Policy Co-Optimization
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2025 (English)In: IROS 2025 - 2025 IEEE/RSJ International Conference on Intelligent Robots and Systems, Conference Proceedings, Institute of Electrical and Electronics Engineers (IEEE) , 2025, p. 21795-21802Conference paper, Published paper (Refereed)
Abstract [en]

Uncertainties in contact dynamics and object geometry remain significant barriers to robust robotic manipulation. Caging helps mitigate these uncertainties by constraining an object's mobility without requiring precise contact modeling. Existing caging research often treats morphology and policy optimization as separate problems, overlooking their synergy. In this paper, we introduce CageCoOpt, a hierarchical framework that jointly optimizes manipulator morphology and control policy for robust caging-based manipulation. The framework employs reinforcement learning for policy optimization at the lower level and multitask Bayesian optimization for morphology optimization at the upper level. We incorporate a caging metric into both optimization levels to encourage caging configurations and thereby improve manipulation robustness. The evaluation consists of four manipulation tasks and demonstrates that co-optimizing morphology and policy improves task performance under uncertainties, establishing caging-guided co-optimization as a viable approach for robust manipulation.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
National Category
Robotics and automation
Identifiers
urn:nbn:se:kth:diva-377826 (URN)10.1109/IROS60139.2025.11246485 (DOI)2-s2.0-105029981629 (Scopus ID)
Conference
2025 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2025, Oct 19 2025 - Oct 25 2025, Hangzhou, China
Note

Part of ISBN 979-8-3315-4393-8

QC 20260306

Available from: 2026-03-06 Created: 2026-03-06 Last updated: 2026-03-06Bibliographically approved
Wang, R., Zhuang, Z., Jin, S., Ingelhag, N., Kragic Jensfelt, D. & Pokorny, F. T. (2025). Feature Extractor or Decision Maker: Rethinking the Role of Visual Encoders in Visuomotor Policies. In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025: . Paper presented at 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025 (pp. 3654-3661). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Feature Extractor or Decision Maker: Rethinking the Role of Visual Encoders in Visuomotor Policies
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2025 (English)In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Institute of Electrical and Electronics Engineers (IEEE) , 2025, p. 3654-3661Conference paper, Published paper (Refereed)
Abstract [en]

An end-to-end (E2E) visuomotor policy is typically treated as a unified whole, but recent approaches using out-of-domain (OOD) data to pretrain the visual encoder have cleanly separated the visual encoder from the network, with the remainder referred to as the policy. We propose Visual Alignment Testing, an experimental framework designed to evaluate the validity of this functional separation. Our results indicate that in E2E-trained models, visual encoders actively contribute to decision-making resulting from motor data supervision, contradicting the assumed functional separation. In contrast, OOD-pretrained models, where encoders lack this capability, experience an average performance drop of 42% in our benchmark results, compared to the state-of-the-art performance achieved by E2E policies. We believe this initial exploration of visual encoders' role can provide a first step towards guiding future pretraining methods to address their decision-making ability, such as developing task-conditioned or context-aware encoders.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
National Category
Computer Sciences
Identifiers
urn:nbn:se:kth:diva-371368 (URN)10.1109/ICRA55743.2025.11127332 (DOI)001582497400330 ()2-s2.0-105016697318 (Scopus ID)
Conference
2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025
Note

Part of ISBN 9798331541392

QC 20251014

Available from: 2025-10-14 Created: 2025-10-14 Last updated: 2026-02-04Bibliographically approved
Zaland, O., Nguyen, C., Pokorny, F. T. & Bhuyan, M. (2025). Federated Learning for Large-Scale Cloud Robotic Manipulation: Opportunities and Challenges. In: Proceedings of 2025 International Conference on Machine Learning and Cybernetics, ICMLC 2025: . Paper presented at 24th International Conference on Machine Learning and Cybernetics, ICMLC 2025, Bali, Indonesia, July 13-15, 2025 (pp. 254-261). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Federated Learning for Large-Scale Cloud Robotic Manipulation: Opportunities and Challenges
2025 (English)In: Proceedings of 2025 International Conference on Machine Learning and Cybernetics, ICMLC 2025, Institute of Electrical and Electronics Engineers (IEEE) , 2025, p. 254-261Conference paper, Published paper (Refereed)
Abstract [en]

Federated Learning (FL) is an emerging distributed machine learning paradigm, where the collaborative training of a model involves dynamic participation of devices to achieve broad objectives. In contrast, classical machine learning (ML) typically requires data to be located on-premises for training, whereas FL leverages numerous user devices to train a shared global model without the need to share private data. Current robotic manipulation tasks are constrained by the individual capabilities and speed of robots due to limited low-latency computing resources. Consequently, the concept of cloud robotics has emerged, allowing robotic applications to harness the flexibility and reliability of computing resources, effectively alleviating their computational demands across the cloud-edge continuum. Undoubtedly, within this distributed computing context, as exemplified in cloud robotic manipulation scenarios, FL offers manifold advantages while also presenting several challenges and opportunities. In this paper, we present fundamental concepts of FL and their connection to cloud robotic manipulation. Additionally, we envision the opportunities and challenges associated with realizing efficient and reliable cloud robotic manipulation at scale through FL, where researchers adapt to design and verify FL models in either centralized or decentralized settings.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
Keywords
Cloud robotics, Federated learning, Robotic manipulation
National Category
Computer Sciences Robotics and automation Computer graphics and computer vision
Identifiers
urn:nbn:se:kth:diva-378762 (URN)10.1109/ICMLC66258.2025.11280176 (DOI)2-s2.0-105031639263 (Scopus ID)
Conference
24th International Conference on Machine Learning and Cybernetics, ICMLC 2025, Bali, Indonesia, July 13-15, 2025
Note

Part of ISBN 9798331587369

QC 20260327

Available from: 2026-03-27 Created: 2026-03-27 Last updated: 2026-03-27Bibliographically approved
Vahs, M., Cabral Muchacho, R. I., Pokorny, F. T. & Tumova, J. (2025). Forward Invariance in Trajectory Spaces for Safety-Critical Control. In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025: . Paper presented at 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025 (pp. 3926-3932). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Forward Invariance in Trajectory Spaces for Safety-Critical Control
2025 (English)In: 2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Institute of Electrical and Electronics Engineers (IEEE) , 2025, p. 3926-3932Conference paper, Published paper (Refereed)
Abstract [en]

Useful robot control algorithms should not only achieve performance objectives but also adhere to hard safety constraints. Control Barrier Functions (CBFs) have been developed to provably ensure system safety through forward invariance. However, they often unnecessarily sacrifice performance for safety since they are purely reactive. Receding horizon control (RHC), on the other hand, consider planned trajectories to account for the future evolution of a system. This work provides a new perspective on safety-critical control by introducing Forward Invariance in Trajectory Spaces (FITS). We lift the problem of safe RHC into the trajectory space and describe the evolution of planned trajectories as a controlled dynamical system. Safety constraints defined over states can be converted into sets in the trajectory space which we render forward invariant via a CBF framework. We derive an efficient quadratic program (QP) to synthesize trajectories that provably satisfy safety constraints. Our experiments support that FITS improves the adherence to safety specifications without sacrificing performance over alternative CBF and NMPC methods.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
National Category
Control Engineering Robotics and automation
Identifiers
urn:nbn:se:kth:diva-371382 (URN)10.1109/ICRA55743.2025.11127715 (DOI)001582497400355 ()2-s2.0-105016634278 (Scopus ID)
Conference
2025 IEEE International Conference on Robotics and Automation, ICRA 2025, Atlanta, United States of America, May 19 2025 - May 23 2025
Note

Part of ISBN 9798331541392

QC 20251009

Available from: 2025-10-09 Created: 2025-10-09 Last updated: 2026-05-29Bibliographically approved
Lu, H., Dong, Y., Weng, Z., Pokorny, F. T., Lundell, J. & Kragic Jensfelt, D. (2025). Grasping a Handful: Sequential Multi-Object Dexterous Grasp Generation. IEEE Robotics and Automation Letters, 10(11), 11880-11887
Open this publication in new window or tab >>Grasping a Handful: Sequential Multi-Object Dexterous Grasp Generation
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2025 (English)In: IEEE Robotics and Automation Letters, E-ISSN 2377-3766, Vol. 10, no 11, p. 11880-11887Article in journal (Refereed) Published
Abstract [en]

We introduce the sequential multi-object robotic grasp sampling algorithm SeqGrasp that can robustly synthesize stable grasps on diverse objects using the robotic hand’s partial Degrees of Freedom (DoF). We use SeqGrasp to construct the large-scale Allegro Hand sequential grasping dataset SeqDataset and use it for training the diffusion-based sequential grasp generator SeqDiffuser. We experimentally evaluate SeqGrasp and SeqDiffuser against the state-of-the-art non-sequential multi-object grasp generation method MultiGrasp in simulation and on a real robot. The experimental results demonstrate that SeqGrasp and SeqDiffuser reach an 8.71%-43.33% higher grasp success rate than MultiGrasp. Furthermore, SeqDiffuser is approximately 1000 times faster at generating grasps than SeqGrasp and MultiGrasp. Project page: https://yulihn.github.io/SeqGrasp/.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2025
Keywords
Data Sets for Robot Learning, Dexterous Manipulation, Grasping
National Category
Computer graphics and computer vision Robotics and automation Computer Sciences
Identifiers
urn:nbn:se:kth:diva-371629 (URN)10.1109/LRA.2025.3614051 (DOI)001594944700028 ()2-s2.0-105017444167 (Scopus ID)
Note

QC 20251017

Available from: 2025-10-17 Created: 2025-10-17 Last updated: 2025-12-05Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0003-1114-6040

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