Materials
Extracting Conceptual Spaces from LLMs Using Prototype Embeddings
Kumar, Nitesh, Chatterjee, Usashi, Schockaert, Steven
Conceptual spaces represent entities and concepts using cognitively meaningful dimensions, typically referring to perceptual features. Such representations are widely used in cognitive science and have the potential to serve as a cornerstone for explainable AI. Unfortunately, they have proven notoriously difficult to learn, although recent LLMs appear to capture the required perceptual features to a remarkable extent. Nonetheless, practical methods for extracting the corresponding conceptual spaces are currently still lacking. While various methods exist for extracting embeddings from LLMs, extracting conceptual spaces also requires us to encode the underlying features. In this paper, we propose a strategy in which features (e.g. sweetness) are encoded by embedding the description of a corresponding prototype (e.g. a very sweet food). To improve this strategy, we fine-tune the LLM to align the prototype embeddings with the corresponding conceptual space dimensions. Our empirical analysis finds this approach to be highly effective.
LogicGuard: Improving Embodied LLM agents through Temporal Logic based Critics
Gokhale, Anand, Srivastava, Vaibhav, Bullo, Francesco
Large language models (LLMs) have shown promise in zero-shot and single step reasoning and decision making problems, but in long horizon sequential planning tasks, their errors compound, often leading to unreliable or inefficient behavior. We introduce LogicGuard, a modular actor-critic architecture in which an LLM actor is guided by a trajectory level LLM critic that communicates through Linear Temporal Logic (LTL). Our setup combines the reasoning strengths of language models with the guarantees of formal logic. The actor selects high-level actions from natural language observations, while the critic analyzes full trajectories and proposes new LTL constraints that shield the actor from future unsafe or inefficient behavior. LogicGuard supports both fixed safety rules and adaptive, learned constraints, and is model-agnostic: any LLM-based planner can serve as the actor, with LogicGuard acting as a logic-generating wrapper. We formalize planning as graph traversal under symbolic constraints, allowing LogicGuard to analyze failed or suboptimal trajectories and generate new temporal logic rules that improve future behavior. To demonstrate generality, we evaluate LogicGuard across two distinct settings: short-horizon general tasks and long-horizon specialist tasks. On the Behavior benchmark of 100 household tasks, LogicGuard increases task completion rates by 25% over a baseline InnerMonologue planner. On the Minecraft diamond-mining task, which is long-horizon and requires multiple interdependent subgoals, LogicGuard improves both efficiency and safety compared to SayCan and InnerMonologue. These results show that enabling LLMs to supervise each other through temporal logic yields more reliable, efficient and safe decision-making for both embodied agents.
DexSkin: High-Coverage Conformable Robotic Skin for Learning Contact-Rich Manipulation
Wistreich, Suzannah, Shi, Baiyu, Tian, Stephen, Clarke, Samuel, Nath, Michael, Xu, Chengyi, Bao, Zhenan, Wu, Jiajun
Human skin provides a rich tactile sensing stream, localizing intentional and unintentional contact events over a large and contoured region. Replicating these tactile sensing capabilities for dexterous robotic manipulation systems remains a longstanding challenge. In this work, we take a step towards this goal by introducing DexSkin. DexSkin is a soft, conformable capacitive electronic skin that enables sensitive, localized, and calibratable tactile sensing, and can be tailored to varying geometries. We demonstrate its efficacy for learning downstream robotic manipulation by sensorizing a pair of parallel jaw gripper fingers, providing tactile coverage across almost the entire finger surfaces. We empirically evaluate DexSkin's capabilities in learning challenging manipulation tasks that require sensing coverage across the entire surface of the fingers, such as reorienting objects in hand and wrapping elastic bands around boxes, in a learning-from-demonstration framework. We then show that, critically for data-driven approaches, DexSkin can be calibrated to enable model transfer across sensor instances, and demonstrate its applicability to online reinforcement learning on real robots. Our results highlight DexSkin's suitability and practicality for learning real-world, contact-rich manipulation. Please see our project webpage for videos and visualizations: https://dex-skin.github.io/.
Towards Rational Pesticide Design with Graph Machine Learning Models for Ecotoxicology
This research focuses on rational pesticide design, using graph machine learning to accelerate the development of safer, eco-friendly agrochemicals, inspired by in silico methods in drug discovery. With an emphasis on ecotoxicology, the initial contributions include the creation of ApisTox, the largest curated dataset on pesticide toxicity to honey bees. We conducted a broad evaluation of machine learning (ML) models for molecular graph classification, including molecular fingerprints, graph kernels, GNNs, and pretrained transformers. The results show that methods successful in medicinal chemistry often fail to generalize to agrochemicals, underscoring the need for domain-specific models and benchmarks. Future work will focus on developing a comprehensive benchmarking suite and designing ML models tailored to the unique challenges of pesticide discovery.
Interaction Topological Transformer for Multiscale Learning in Porous Materials
Chen, Dong, Liu, Jian, Chen, Chun-Long, Wei, Guo-Wei
Porous materials exhibit vast structural diversity and support critical applications in gas storage, separations, and catalysis. However, predictive modeling remains challenging due to the multiscale nature of structure-property relationships, where performance is governed by both local chemical environments and global pore-network topology. These complexities, combined with sparse and unevenly distributed labeled data, hinder generalization across material families. We propose the Interaction Topological Transformer (ITT), a unified data-efficient framework that leverages novel interaction topology to capture materials information across multiple scales and multiple levels, including structural, elemental, atomic, and pairwise-elemental organization. ITT extracts scale-aware features that reflect both compositional and relational structure within complex porous frameworks, and integrates them through a built-in Transformer architecture that supports joint reasoning across scales. Trained using a two-stage strategy, i.e., self-supervised pretraining on 0.6 million unlabeled structures followed by supervised fine-tuning, ITT achieves state-of-the-art, accurate, and transferable predictions for adsorption, transport, and stability properties. This framework provides a principled and scalable path for learning-guided discovery in structurally and chemically diverse porous materials.
Speech Vecalign: an Embedding-based Method for Aligning Parallel Speech Documents
We present Speech Vecalign, a parallel speech document alignment method that monotonically aligns speech segment embeddings and does not depend on text transcriptions. Compared to the baseline method Global Mining, a variant of speech mining, Speech Vecalign produces longer speech-to-speech alignments. It also demonstrates greater robustness than Local Mining, another speech mining variant, as it produces less noise. We applied Speech Vecalign to 3,000 hours of unlabeled parallel English-German (En-De) speech documents from VoxPopuli, yielding about 1,000 hours of high-quality alignments. We then trained En-De speech-to-speech translation models on the aligned data. Speech Vecalign improves the En-to-De and De-to-En performance over Global Mining by 0.37 and 0.18 ASR-BLEU, respectively. Moreover, our models match or outperform SpeechMatrix model performance, despite using 8 times fewer raw speech documents.
Underground Multi-robot Systems at Work: a revolution in mining
Puche, Victor V., Verma, Kashish, Fumagalli, Matteo
The growing global demand for critical raw materials (CRMs) has highlighted the need to access difficult and hazardous environments such as abandoned underground mines. These sites pose significant challenges for conventional machinery and human operators due to confined spaces, structural instability, and lack of infrastructure. To address this, we propose a modular multi-robot system designed for autonomous operation in such environments, enabling sequential mineral extraction tasks. Unlike existing work that focuses primarily on mapping and inspection through global behavior or central control, our approach incorporates physical interaction capabilities using specialized robots coordinated through local high-level behavior control. Our proposed system utilizes Hierarchical Finite State Machine (HFSM) behaviors to structure complex task execution across heterogeneous robotic platforms. Each robot has its own HFSM behavior to perform sequential autonomy while maintaining overall system coordination, achieved by triggering behavior execution through inter-robot communication. This architecture effectively integrates software and hardware components to support collaborative, task-driven multi-robot operation in confined underground environments.
Pose Estimation of a Cable-Driven Serpentine Manipulator Utilizing Intrinsic Dynamics via Physical Reservoir Computing
Tanaka, Kazutoshi, Takahashi, Tomoya, Hamaya, Masashi
Cable-driven serpentine manipulators hold great potential in unstructured environments, offering obstacle avoidance, multi-directional force application, and a lightweight design. By placing all motors and sensors at the base and employing plastic links, we can further reduce the arm's weight. To demonstrate this concept, we developed a 9-degree-of-freedom cable-driven serpentine manipulator with an arm length of 545 mm and a total mass of only 308 g. However, this design introduces flexibility-induced variations, such as cable slack, elongation, and link deformation. These variations result in discrepancies between analytical predictions and actual link positions, making pose estimation more challenging. To address this challenge, we propose a physical reservoir computing based pose estimation method that exploits the manipulator's intrinsic nonlinear dynamics as a high-dimensional reservoir. Experimental results show a mean pose error of 4.3 mm using our method, compared to 4.4 mm with a baseline long short-term memory network and 39.5 mm with an analytical approach. This work provides a new direction for control and perception strategies in lightweight cable-driven serpentine manipulators leveraging their intrinsic dynamics.
ChemOrch: Empowering LLMs with Chemical Intelligence via Synthetic Instructions
Huang, Yue, Jiang, Zhengzhe, Luo, Xiaonan, Guo, Kehan, Zhuang, Haomin, Zhou, Yujun, Yuan, Zhengqing, Sun, Xiaoqi, Schleinitz, Jules, Wang, Yanbo, Zhang, Shuhao, Surve, Mihir, Chawla, Nitesh V, Wiest, Olaf, Zhang, Xiangliang
Empowering large language models (LLMs) with chemical intelligence remains a challenge due to the scarcity of high-quality, domain-specific instruction-response datasets and the misalignment of existing synthetic data generation pipelines with the inherently hierarchical and rule-governed structure of chemical information. To address this, we propose ChemOrch, a framework that synthesizes chemically grounded instruction-response pairs through a two-stage process: task-controlled instruction generation and tool-aware response construction. ChemOrch enables controllable diversity and levels of difficulty for the generated tasks, and ensures response precision through tool planning and distillation, and tool-based self-repair mechanisms. The effectiveness of ChemOrch is evaluated based on: 1) the high quality of generated instruction data, demonstrating superior diversity and strong alignment with chemical constraints; 2) the reliable generation of evaluation tasks that more effectively reveal LLM weaknesses in chemistry; and 3) the significant improvement of LLM chemistry capabilities when the generated instruction data are used for fine-tuning. Our work thus represents a critical step toward scalable and verifiable chemical intelligence in LLMs.
Miniature soft robot with magnetically reprogrammable surgical functions
Ng, Chelsea Shan Xian, Yeoh, Yu Xuan, Foo, Nicholas Yong Wei, Radhakrishnan, Keerthana, Lum, Guo Zhan
Miniature robots are untethered actuators, which have significant potential to make existing minimally invasive surgery considerably safer and painless, and enable unprecedented treatments because they are much smaller and dexterous than existing surgical robots. Of the miniature robots, the magnetically actuated ones are the most functional and dexterous. However, existing magnetic miniature robots are currently impractical for surgery because they are either restricted to possessing at most two on-board functionalities or having limited five degrees-of-freedom (DOF) locomotion. Some of these actuators are also only operational under specialized environments where actuation from strong external magnets must be at very close proximity (< 4 cm away). Here we present a millimeter-scale soft robot where its magnetization profile can be reprogrammed upon command to perform five surgical functionalities: drug-dispensing, cutting through biological tissues (simulated with gelatin), gripping, storing (biological) samples and remote heating. By possessing full six-DOF motions, including the sixth-DOF rotation about its net magnetic moment, our soft robot can also roll and two-anchor crawl across challenging unstructured environments, which are impassable by its five-DOF counterparts. Because our actuating magnetic fields are relatively uniform and weak (at most 65 mT and 1.5 T/m), such fields can theoretically penetrate through biological tissues harmlessly and allow our soft robot to remain controllable within the depths of the human body. We envision that this work marks a major milestone for the advancement of soft actuators, and towards revolutionizing minimally invasive treatments with untethered miniature robots that have unprecedented functionalities.