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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Chakraborty, Tirthankar Maity, Arnab Intelligent Systems and Control Lab Department of Aerospace Engineering Indian Institute of Technology Bombay Mumbai400076 India

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

Fault tolerance is crucial in the design and operation of gas turbine engines, where even minor malfunctions can disrupt operations and compromise performance. This paper presents a modified covariance intersection-based decentralized estimator which can ensure uninterrupted operation amidst sensor failures. A network of sensor nodes within the engine is considered. Each node in the network computes a local state estimate, which is subsequently fused with the other node estimates at each time instant. The developed algorithm uses a novel weight adaptation scheme to fuse the node estimates and the associated covariances. The node weights are expressed as a function of the covariance matrix of the node estimate and a scaling matrix. This algorithm is tested through simulation by injecting faults in the sensors of a small-scale gas turbine engine primarily used for research, called the SR-30 engine. The simulation results illustrate the effectiveness of the proposed estimator in ensuring the integrity of the state estimates in the presence of drift and bias faults in the sensors. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Gas turbines

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Nested Sliding Mode control Based Impact Angle Guidance with Bounded Input

Nested Sliding Mode Control Based Impact Angle Guidance with...

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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Surve, Prajakta Kumar, Shashi Ranjan Intelligent Systems & Control Lab Department of Aerospace Engineering Indian Institute of Technology Bombay Powai Mumbai400076 India

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

In this paper, a nonlinear guidance law for impact angle-constrained interception of nonmaneuvering targets, respecting the bounds on the control input - the commanded interceptor lateral acceleration, is proposed. By modeling the required interceptor lateral acceleration as a first-order dynamics, which is a function of the maximum permissible value of control input and guidance command, the control input is maintained within the predefined bounds. The dynamics is chosen in such a way that the resulting input will never violate the prescribed bounds. To design the guidance command, also known as commanded lateral acceleration, we employ a sliding surface based on the error between actual and desired line-of-sight (LOS) angles and the LOS rate, facilitating a collision course with zero miss distance. A secondary sliding surface is designed as a function of the primary sliding surface and its rate. This sliding surface enables the control over the required interceptor lateral acceleration. An effective guidance command for precise interception at given impact angle, considering the bounds on control input, is then derived using the sliding mode control technique. Numerical simulations validate the merits and claims of the presented guidance approach. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Sliding mode control

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Adaptive Unscented Kalman Filter Based Sensor Fusion for Aircraft Positioning Relative to Unknown Runway

Adaptive Unscented Kalman Filter Based Sensor Fusion for Air...

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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Ghosh, Nabarun Maity, Arnab Intelligent Systems and Control Lab Department of Aerospace Engineering Indian Institute of Technology Bombay Maharashtra Mumbai400076 India

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

This paper proposes an estimator to provide precise position, velocity, and orientation for a landing aircraft relative to the runway based on image sensors, IMU sensor data, and barometric sensor measurements. This work excludes GPS data, as it is expected that the proposed estimator can be used for fault detection in GPS and instrument landing systems. The runway is unknown, and hence, its width is estimated online. An adaptive UKF-based approach is adopted to estimate the states. In order to verify the nearer-to-practical performance and accuracy of bias estimation, realistically simulated data that constitute noises and biases from the sensors are taken into consideration. The proposed approach provides a solution for nonlinear state estimation in the presence of measurement noises that are non-additive. In addition to this, it provides estimates of the unknown measurement noise covariance. A comparative study is conducted between the conventional UKF and the proposed AUKF to analyze the adopted approach. Results show that the proposed algorithm gives comparable estimation results and faster convergence than the conventional UKF. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Fault detection

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Ptychographic characterization of spatiotemporal wavepackets

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Optica 2025年第4期12卷 498-504页

作者： Liu, Yuanyuan Xu, Yingming Zhang, Nianjia Liu, Dawei Wei, Lijin Cao, Qian Shi, Junhui Zhan, Qiwen School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai200093 China Zhangjiang Laboratory 100 Haike Road Shanghai201204 China Research Center for Novel Computational Sensing and Intelligent Processing Zhejiang Lab. Hangzhou311100 China College of Mechatronics and Control Engineering Shenzhen University Shenzhen518060 China

Exciting advances in spatiotemporal wavepackets have shown great potential in a range of applications, including particle manipulation, time-resolved imaging, and unique light–matter interactions. In particular, spatiotemporal optical vortice (STOV) pulse beams characterized by a helical phase structure in space and time are a recently emerging type of complex structured ultrashort pulse. However, the high-resolution measurement and manipulation of ultrashort spatiotemporal wavepackets still face major challenges due to their inseparable properties in space and time. In this study, based on spectra-encoded ptychography, we implement a simple, compact, reference-free STOV characterization technique with a temporal resolution of 6 fs and a spatial resolution of 11.05 µm. This technique can be employed to analyze various intricate spatiotemporal structural beams, contributing to the growing field of spatiotemporally engineered ultrafast laser pulse beams. Additionally, as a lensless measurement technique, this characterization method may be extended to other spectral ranges, including the extreme ultraviolet and X-ray domains. © 2025 Optica Publishing Group.

关键词： Wave packets

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Impact Time Constrained Guidance with Bounded Field-of-View and Input

Impact Time Constrained Guidance with Bounded Field-of-View ...

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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Singh, Swati Kumar, Shashi Ranjan Mukherjee, Dwaipayan Intelligent Systems and Control Lab Department of Aerospace Engineering Indian Institute of Technology Bombay Powai Mumbai400 076 India Department of Electrical Engineering Indian Institute of Technology Bombay Powai Mumbai400 076 India

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

This article proposes a guidance scheme for stationary targets to achieve time-constrained interception at a desired time, considering the bounded field-of-view capability of seekerequipped interceptors and the physical limits of the actuator. Actuator saturation is a crucial problem in physical systems, often resulting in performance degradation. However, the actuator limitations are usually known to the designer, therefore, augmenting these constraints into the guidance design may enhance performance. The time-to-go error-based approach is used to satisfy the field-of-view constraint;further, the engagement kinematics are augmented with an input saturation model to incorporate the lateral acceleration constraints. Subsequently, the guidance strategy that constrains the lateral acceleration and the time-to-go values within their respective bounds is derived using Lyapunov stability concepts and the backstepping technique. Furthermore, a multi-stage approach is suggested to expand the achievable range of impact time. Numerical simulations are performed to validate the efficacy of the proposed scheme for different initial engagement geometries. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Backstepping

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An Integrated Sensor Array for Water Quality Monitoring

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IET Science, Measurement and Technology 2025年第1期19卷

作者： Abolfathi, Hooman Nikfarjam, Alireza Abbaspour, Bahareh MEMS&NEMS Lab. Department of Microsystem and Photonics School of Intelligent Systems Engineering University of Tehran Tehran Iran

Four important quantities in water quality monitoring are temperature, specific electrical conductivity (EC), total dissolved solids (TDS), and pH. In this paper, three sensors for precisely detecting these parameters were designed and fabricated in one structure. Spiral electrodes were made as temperature sensors and circular toothed electrodes were made as EC sensors. The pH sensor comprises two electrodes: the reference electrode (Ag/AgCl) and the working electrode (carbon black/highly porous polyaniline). The response time of the temperature sensor is 13.2 s, and the stability of the sensor is −0.031 (Formula presented.), and the sensitivity of the sensor is 0.003 (Formula presented.). The response time of the pH sensor was reported as 136.2 (Formula presented.) and the sensor's sensitivity was 8.8 (Formula presented.) in the pH range of 4 to 10. Also, the best excitation frequency of 30 kHz and the best reference resistance of 1 (Formula presented.) were measured in the range of 100 to 2000 (Formula presented.) and the sensitivity of the EC sensor is (Formula presented.) (Formula presented.). TDS was also calculated from the specific electrical conductivity using the conversion factor of 0.66 (Formula presented.). Considering the electrical output of all sensors, a circuit was designed and built to receive their information. Operational amplifiers with different functions were used to create the reading circuit. © 2025 The Author(s). IET Science, Measurement & Technology published by John Wiley & Sons Ltd on behalf of The Institution of engineering and Technology.

关键词： Sensor arrays

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Adaptive Differentially Private Robust Federated Learning Against Backdoor Attacks 1

Adaptive Differentially Private Robust Federated Learning Ag...

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1st International Conference on intelligent Manufacturing and Cloud Computing, ICIMCC 2024

作者： Yao, Ruixiang Wen, Hong Hou, Wenjing Ma, Wendi Sun, Fan Zhao, Ziang School of Aeronautics and Astronautics University of Elec.Science and Tech. of China Chengdu611731 China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Lab. of Sichuan Province UESTC 611731 China Intelligent IoT Communication Technology Engineering Research Center of Sichuan Province UESTC 611731 China

ISBN: (纸本)9781643685779

In federated learning systems, malicious attackers can manipulate training datasets by injecting backdoor triggers to achieve data poisoning. Addressing this vulnerability, this paper proposes a new defense method, the adaptive differential privacy stochastic gradient descent (ADP-SGD) algorithm, which increases the Euclidean distance between malicious and benign updates to enhance aggregation efficiency. Experiments were conducted on typical datasets, and the results show that combining ADP-SGD with the m-Krum aggregation algorithm can effectively defend against backdoor attacks in complex attack environments. While ensuring the accuracy of the main task, it significantly reduces the success rate of backdoor attacks, especially under the condition of unknown proportions of malicious participants, proving to be effective and robust. © 2025 The Authors.

关键词： Federated learning

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Design of Orthogonal Polyphase Codes for MIMO Radar Using an Enhanced Salp Swarm Algorithm 1

Design of Orthogonal Polyphase Codes for MIMO Radar Using an...

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1st International Conference on intelligent Manufacturing and Cloud Computing, ICIMCC 2024

作者： Pang, Yu Zhao, Runhui Wen, Hong Wang, Yongfeng Feng, Xuewei Tang, Tao Zhao, Ziang Ma, Wendi School of Aeronautics and Astronautics University of Elec.Science and Tech. of China Chengdu611731 China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Lab. of Sichuan Province UESTC 611731 China Intelligent IoT Communication Technology Engineering Research Center of Sichuan Province UESTC 611731 China

ISBN: (纸本)9781643685779

This paper presents the design of highly orthogonal waveforms focusing on minimizing autocorrelation sidelobes and cross-correlation peaks. An enhanced Salp Swarm Algorithm is proposed to improve global search capabilities through refined population initialization and leader position updates. The feasibility and benefits of this approach are demonstrated through practical implementation. © 2025 The Authors.

关键词： MIMO radar

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Robust Offline Imitation Learning Through State-level Trajectory Stitching

arXiv

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arXiv 2025年

作者： Wang, Shuze Mei, Yunpeng Cao, Hongjie Yuan, Yetian Wang, Gang Sun, Jian Chen, Jie National Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology Beijing100081 China Department of Control Science and Engineering Harbin Institute of Technology Harbin150001 China

Imitation learning (IL) has proven effective for enabling robots to acquire visuomotor skills through expert demonstrations. However, traditional IL methods are limited by their reliance on high-quality, often scarce, expert data, and suffer from covariate shift. To address these challenges, recent advances in offline IL have incorporated suboptimal, unlab.led datasets into the training. In this paper, we propose a novel approach to enhance policy learning from mixed-quality offline datasets by leveraging task-relevant trajectory fragments and rich environmental dynamics. Specifically, we introduce a state-based search framework that stitches state-action pairs from imperfect demonstrations, generating more diverse and informative training trajectories. Experimental results on standard IL benchmarks and real-world robotic tasks showcase that our proposed method significantly improves both generalization and performance. Videos are availab.e on https://***/sbr. Copyright © 2025, The Authors. All rights reserved.

关键词： Trajectories

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Towards Safer and Smarter Integration of Conflict Management Algorithms: A Quantitative and Comparative Study

Towards Safer and Smarter Integration of Conflict Management...

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Innovative Research in Applied Science, engineering and Technology (IRASET),Conference on

作者： Abdelatif Ibourk Naoual Beluoaggadia Salah Nissabouri Hamza Ennadafy Mustapha Jammoukh Lab. of Modeling and Simulation of Intelligent Industrial Systems (M2S2I) Hassan II University of Casablanca Casablanca Morocco Builders Lab Builders School of Engineering COMUE Normandie Université France

ISBN: (数字)9798331532970

ISBN: (纸本)9798331532987

Autonomous vehicles (AVs) face significant challenges in overtaking maneuvers, where balancing safety, efficiency, and adaptability is crucial. This paper provides a quantitative and comparative analysis of conflict management algorithms, including Reinforcement Learning (RL), Model Predictive control (MPC), and Game Theory, assessing their strengths and limitations in handling decision-making under uncertainty. Through bibliometric evaluation and performance assessment, we highlight gaps in existing methods and propose a hybrid approach that integrates multiple decision-making paradigms to enhance robustness, adaptability, and real-time responsiveness. This study lays the groundwork for more intelligent and reliable overtaking strategies, addressing a critical aspect of AV decision-making.

关键词： Uncertainty Reinforcement learning Reliability theory Prediction algorithms Robustness Real-time systems Safety Planning Game theory Predictive control

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