vio
Semantic Bridges Between First Order c-Representations and Cost-Based Semantics: An Initial Perspective
Leisegang, Nicholas, Casini, Giovanni, Meyer, Thomas
Weighted-knowledge bases and cost-based semantics represent a recent formalism introduced by Bienvenu et al. for Ontology Mediated Data Querying in the case where a given knowledge base is inconsistent. This is done by adding a weight to each statement in the knowledge base (KB), and then giving each DL interpretation a cost based on how often it breaks rules in the KB. In this paper we compare this approach with c-representations, a form of non-monotonic reasoning originally introduced by Kern-Isberner. c-Representations describe a means to interpret defeasible concept inclusions in the first-order case. This is done by assigning a numerical ranking to each interpretations via penalties for each violated conditional. We compare these two approaches on a semantic level. In particular, we show that under certain conditions a weighted knowledge base and a set of defeasible conditionals can generate the same ordering on interpretations, and therefore an equivalence of semantic structures up to relative cost. Moreover, we compare entailment described in both cases, where certain notions are equivalently expressible in both formalisms. Our results have the potential to benefit further work on both cost-based semantics and c-representations
JARVIS: A Multi-Agent Code Assistant for High-Quality EDA Script Generation
Pasandi, Ghasem, Kunal, Kishor, Tej, Varun, Shah, Kunjal, Sun, Hanfei, Jain, Sumit, Li, Chunhui, Deng, Chenhui, Ene, Teodor-Dumitru, Ren, Haoxing, Pratty, Sreedhar
--This paper presents JARVIS, a novel multi-agent framework that leverages Large Language Models (LLMs) and domain expertise to generate high-quality scripts for specialized Electronic Design Automation (EDA) tasks. By combining a domain-specific LLM trained with synthetically generated data, a custom compiler for structural verification, rule enforcement, code fixing capabilities, and advanced retrieval mechanisms, our approach achieves significant improvements over state-of-the-art domain-specific models. Our framework addresses the challenges of data scarcity and hallucination errors in LLMs, demonstrating the potential of LLMs in specialized engineering domains. We evaluate our framework on multiple benchmarks and show that it outperforms existing models in terms of accuracy and reliability. Our work sets a new precedent for the application of LLMs in EDA and paves the way for future innovations in this field. Large Language Models (LLMs) have revolutionized software development by automating various coding tasks, streamlining repetitive processes, and enhancing developer productivity. Tools like Microsoft's Copilot and Meta's CodeLlama have demonstrated the potential of LLMs in generating boilerplate code, automating common patterns, and embedding best practices within generated outputs [3], [17], [21]. However, when applied to specialized fields like V ery-Large-Scale Integration (VLSI) design within Electronic Design Automation (EDA), LLM performance is hindered by the scarcity of relevant training data, leading to unreliable and inaccurate outputs. These models often misinterpret and hallucinate due to a lack of contextual depth, highlighting the need for domain-specific fine-tuning. Recent efforts have focused on enhancing the reasoning capabilities of LLM models using CoT [23] and agent-based frameworks [24] for general tasks.
Survey-to-Behavior: Downstream Alignment of Human Values in LLMs via Survey Questions
Nie, Shangrui, Mai, Florian, Kaczรฉr, David, Welch, Charles, Zhao, Zhixue, Flek, Lucie
Large language models implicitly encode preferences over human values, yet steering them often requires large training data. In this work, we investigate a simple approach: Can we reliably modify a model's value system in downstream behavior by training it to answer value survey questions accordingly? We first construct value profiles of several open-source LLMs by asking them to rate a series of value-related descriptions spanning 20 distinct human values, which we use as a baseline for subsequent experiments. We then investigate whether the value system of a model can be governed by fine-tuning on the value surveys. We evaluate the effect of finetuning on the model's behavior in two ways; first, we assess how answers change on in-domain, held-out survey questions. Second, we evaluate whether the model's behavior changes in out-of-domain settings (situational scenarios). To this end, we construct a contextualized moral judgment dataset based on Reddit posts and evaluate changes in the model's behavior in text-based adventure games. We demonstrate that our simple approach can not only change the model's answers to in-domain survey questions, but also produces substantial shifts (value alignment) in implicit downstream task behavior.
A Multi-view Landmark Representation Approach with Application to GNSS-Visual-Inertial Odometry
Hua, Tong, Han, Jiale, Ouyang, Wei
Invariant Extended Kalman Filter (IEKF) has been a significant technique in vision-aided sensor fusion. However, it usually suffers from high computational burden when jointly optimizing camera poses and the landmarks. To improve its efficiency and applicability for multi-sensor fusion, we present a multi-view pose-only estimation approach with its application to GNSS-Visual-Inertial Odometry (GVIO) in this paper. Our main contribution is deriving a visual measurement model which directly associates landmark representation with multiple camera poses and observations. Such a pose-only measurement is proven to be tightly-coupled between landmarks and poses, and maintain a perfect null space that is independent of estimated poses. Finally, we apply the proposed approach to a filter based GVIO with a novel feature management strategy. Both simulation tests and real-world experiments are conducted to demonstrate the superiority of the proposed method in terms of efficiency and accuracy.
Systematic Evaluation of Knowledge Graph Repair with Large Language Models
Lin, Tung-Wei, Fierro, Gabe, Li, Han, Hong, Tianzhen, Nuzzo, Pierluigi, Sangiovanni-Vinentelli, Alberto
We present a systematic approach for evaluating the quality of knowledge graph repairs with respect to constraint violations defined in shapes constraint language (SHACL). Current evaluation methods rely on \emph{ad hoc} datasets, which limits the rigorous analysis of repair systems in more general settings. Our method addresses this gap by systematically generating violations using a novel mechanism, termed violation-inducing operations (VIOs). We use the proposed evaluation framework to assess a range of repair systems which we build using large language models. We analyze the performance of these systems across different prompting strategies. Results indicate that concise prompts containing both the relevant violated SHACL constraints and key contextual information from the knowledge graph yield the best performance.
SaWa-ML: Structure-Aware Pose Correction and Weight Adaptation-Based Robust Multi-Robot Localization
Choi, Junho, Ryoo, Kihwan, Kim, Jeewon, Kim, Taeyun, Lee, Eungchang, Jeong, Myeongwoo, Marsim, Kevin Christiansen, Lim, Hyungtae, Myung, Hyun
Multi-robot localization is a crucial task for implementing multi-robot systems. Numerous researchers have proposed optimization-based multi-robot localization methods that use camera, IMU, and UWB sensors. Nevertheless, characteristics of individual robot odometry estimates and distance measurements between robots used in the optimization are not sufficiently considered. In addition, previous researches were heavily influenced by the odometry accuracy that is estimated from individual robots. Consequently, long-term drift error caused by error accumulation is potentially inevitable. In this paper, we propose a novel visual-inertial-range-based multi-robot localization method, named SaWa-ML, which enables geometric structure-aware pose correction and weight adaptation-based robust multi-robot localization. Our contributions are twofold: (i) we leverage UWB sensor data, whose range error does not accumulate over time, to first estimate the relative positions between robots and then correct the positions of each robot, thus reducing long-term drift errors, (ii) we design adaptive weights for robot pose correction by considering the characteristics of the sensor data and visual-inertial odometry estimates. The proposed method has been validated in real-world experiments, showing a substantial performance increase compared with state-of-the-art algorithms.
Structureless VIO
Song, Junlin, Olivares-Mendez, Miguel
Visual odometry (VO) is typically considered as a chicken-and-egg problem, as the localization and mapping modules are tightly-coupled. The estimation of a visual map relies on accurate localization information. Meanwhile, localization requires precise map points to provide motion constraints. This classical design principle is naturally inherited by visual-inertial odometry (VIO). Efficient localization solutions that do not require a map have not been fully investigated. To this end, we propose a novel structureless VIO, where the visual map is removed from the odometry framework. Experimental results demonstrated that, compared to the structure-based VIO baseline, our structureless VIO not only substantially improves computational efficiency but also has advantages in accuracy.
Robust Reinforcement Learning-Based Locomotion for Resource-Constrained Quadrupeds with Exteroceptive Sensing
Plozza, Davide, Apostol, Patricia, Joseph, Paul, Schlรคpfer, Simon, Magno, Michele
-- Compact quadrupedal robots are proving increasingly suitable for deployment in real-world scenarios. Nevertheless, real-time locomotion on uneven terrains remains challenging, particularly due to the high computational demands of terrain perception. This paper presents a robust reinforcement learning-based exteroceptive locomotion controller for resource-constrained small-scale quadrupeds in challenging terrains, which exploits real-time elevation mapping, supported by a careful depth sensor selection. We concurrently train both a policy and a state estimator, which together provide an odom-etry source for elevation mapping, optionally fused with visual-inertial odometry (VIO). We demonstrate the importance of positioning an additional time-of-flight sensor for maintaining robustness even without VIO, thus having the potential to free up computational resources. We experimentally demonstrate that the proposed controller can flawlessly traverse steps up to 17.5 cm in height and achieve an 80% success rate on 22.5 cm steps, both with and without VIO. The proposed controller also achieves accurate forward and yaw velocity tracking of up to 1.0 m/s and 1.5 rad/s respectively. Small-scale quadrupedal robots are becoming increasingly viable for real-world applications [1].
A New Tightly-Coupled Dual-VIO for a Mobile Manipulator With Dynamic Locomotion
This paper introduces a new dual monocular visualinertial odometry (dual-VIO) strategy for a mobile manipulator operating under dynamic locomotion, i.e. coordinated movement involving both the base platform and the manipulator arm. Our approach has been motivated by challenges arising from inaccurate estimation due to coupled excitation when the mobile manipulator is engaged in dynamic locomotion in cluttered environments. The technique maintains two independent monocular VIO modules, with one at the mobile base and the other at the end-effector (EE), which are tightly coupled at the low level of the factor graph. The proposed method treats each monocular VIO with respect to each other as a positional anchor through arm-kinematics. These anchor points provide a soft geometric constraint during the VIO pose optimization. This allows us to stabilize both estimators in case of instability of one estimator in highly dynamic locomotions. The performance of our approach has been demonstrated through extensive experimental testing with a mobile manipulator tested in comparison to running dual VINS-Mono in parallel. We envision that our method can also provide a foundation towards active-SLAM (ASLAM) with a new perspective on multi-VIO fusion and system redundancy.
Range-Visual-Inertial Sensor Fusion for Micro Aerial Vehicle Localization and Navigation
Goudar, Abhishek, Zhao, Wenda, Schoellig, Angela P.
We propose a fixed-lag smoother-based sensor fusion architecture to leverage the complementary benefits of range-based sensors and visual-inertial odometry (VIO) for localization. We use two fixed-lag smoothers (FLS) to decouple accurate state estimation and high-rate pose generation for closed-loop control. The first FLS combines ultrawideband (UWB)-based range measurements and VIO to estimate the robot trajectory and any systematic biases that affect the range measurements in cluttered environments. The second FLS estimates smooth corrections to VIO to generate pose estimates at a high rate for online control. The proposed method is lightweight and can run on a computationally constrained micro-aerial vehicle (MAV). We validate our approach through closed-loop flight tests involving dynamic trajectories in multiple real-world cluttered indoor environments. Our method achieves decimeter-to-sub-decimeter-level positioning accuracy using off-the-shelf sensors and decimeter-level tracking accuracy with minimally-tuned open-source controllers.