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IEEE Instrumentation and Measurement technology Conference

作者： Jie Zheng YiFei Chen Xiang Yu Li Xin Zhang Yi Shen Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798350380903

ISBN: (纸本)9798350380910

Ultrasound imaging is characterized by low resolution due to the point spread function, which limits its application in medical diagnosis. Most improvement algorithms proposed for the point spread function ignore its spatial variability, and there is still a need for improvement. In this paper, we propose an ultrasound image improvement method based on the parameter optimization of the spatially variable point spread function, which takes into account the spatial variability of the point spread function while modeling the point spread function, and determines the desired spatially variable point spread function through parameter optimization. Better beam parameters and image quality are achieved by the method, and its validity is verified on both simulation data and experimental data.

关键词： Image quality Ultrasonic imaging Accuracy Imaging Apertures Medical diagnosis Instrumentation and measurement

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A Day-Ahead Market Clearing Model Under System Inertia Constraints 16

A Day-Ahead Market Clearing Model Under System Inertia Const...

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16th IEEE PES Asia-Pacific Power and Energy engineering Conference, APPEEC 2024

作者： Ma, Yuting Jin, Jiangliang Hao, Liangliang Huang, Qisheng Shen, Liye College of Information Scienc and Technology Donghua University Shanghai China Shandong University Department of Control Science and Engineering Shandong China School of Mechanical Engineering and Automation Harbin Institute of Technology Shanghai China

ISBN: (纸本)9798350386127

We study the market clearing model for electric energy, inertia, and reserve in the day-ahead market, with a particular focus on the virtual inertia provided by wind units. In this paper, we consider synchronous inertia and virtual inertia as sources of system inertia. We incorporate system inertia constraints into the unit commitment (UC) and the economic dispatch (ED) models, and assign economic value to virtual inertia, so as to incentivize wind power to provide virtual inertia. Numerical results demonstrate that the proposed model enhances the participation of wind power units, increases the wind utilization rate and reduces the total costs. © 2024 IEEE.

关键词： Wind power

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Active steering angle tracking control of steer-by-wire system under different external disturbance

Active steering angle tracking control of steer-by-wire syst...

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Chinese control and Decision Conference, CCDC

作者： Xin Zhao Linhui Zhao Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798350387780

ISBN: (纸本)9798350387797

In the context of vehicle intelligence, steer-by-wire (SbW) has great potential for development and has become a current research hotspot. A challenging key technology of the SbW system is the steering angle tracking control under the effect of wheel-ground coupling resistance torque. In this paper, a method is proposed to provide the wheel-ground coupling resistance torque of the system by controlling the motor to track the desired torque to apply reaction force to the SbW system, which is referred to as reaction force analog control. The reaction force analog control strategy based on proportional integral (PI) control is proposed for the brushless DC motor (BLDC) with Hall sensor. Meanwhile, a method for estimating the angle and velocity of the BLDC based on Hall sensor is presented for field-oriented control. Besides, a steering angle tracking control strategy based on PI control is designed for the permanent magnet synchronous motor (PMSM) with resolver to achieve excellent steering performance. The proposed algorithms are validated with different driving test cycles from ISO standards via hardware-in-loop experiments. The experimental results show that the designed reaction force analog control can accurately track the desired resistance torque and the proposed active steering angle tracking controller achieves high-precision steering angle tracking performance under external disturbance, which it well meets the requirements of embedded applications.

关键词： Resistance Couplings Uncertain systems Torque Accuracy Roads Force

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Estimation of RoA for Nonlinear Systems Based on Gaussian Processes

Estimation of RoA for Nonlinear Systems Based on Gaussian Pr...

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International Conference on Electronic engineering and Informatics (EEI)

作者： Yucheng Chen Yupeng Zhu Hongming Zhu Quanqi Zhang Chengwei Wu Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798350353594

ISBN: (纸本)9798350353600

This paper employs Gaussian Processes (GPs) to estimate uncertainty dynamics inherent in nonlinear systems. A control policy ensuring the system satisfies initial stability constraints is derived using linear quadratic regulator (LQR). By modeling the Lyapunov function based on uncertain dynamics as GPs, the stability of the system dynamics in the Lyapunov sense is ensured. To discretize the Lyapunov function with Lipschitz continuity, a finite number of discrete points are chosen to represent the properties of the function. The region of attraction (RoA) based on Lyapunov function is widely utilized as a safe constraint in the field of control. Additionally, the maximum uncertainty dynamics are chosen as the boundary for exploration to expand the evaluation of the RoA. Finally, a simulation example is provided to demonstrate the effectiveness of the proposed approach.

关键词： Uncertainty Regulators System dynamics Estimation Gaussian processes Stability analysis Nonlinear dynamical systems Informatics Thermal stability Lyapunov methods

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Friction Modeling and control Compensation for Electromechanical Braking Systems

Friction Modeling and Control Compensation for Electromechan...

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Conference on Vehicle control and Intelligence (CVCI)

作者： Jing Houhua Lin Qinggan Liu Mingqi Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798331504892

ISBN: (纸本)9798331504908

Influenced by the electrification and intelligence of automobile chassis, electromechanical braking has become the future brake-by-wire trend choice by virtue of its simpler mechanism and faster servo performance, while system friction, as a key factor of its servo control, must be handled properly. This work studies the system friction modeling of electromechanical braking system and the corresponding control compensation approach. First, by evaluating the structure and working principle of the electromechanical braking system, the system model is produced, the braking control test rig is built and the system characteristic test is carried out. Then, the friction model parameters were identified from the experimental data based on the examination of system features. Finally, the brake control performance after friction compensation was experimentally validated by the physical rig, which verified the effectiveness of the friction model and its control compensation.

关键词： Analytical models Accuracy Parameter estimation Friction Force Clamps Force control Servomotors Optimization Testing

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Generative Adversarial Network with In-Betweening for Fine-Grained Skeleton-Based Action Generation

Generative Adversarial Network with In-Betweening for Fine-G...

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Annual Conference of Industrial Electronics Society

作者： Xiangyuan Qi Zhen He Qiang Wang Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9781665464543

ISBN: (纸本)9781665464550

Human action generation has shown critical value in both industry application and academic research, especially fine-grained skeleton-based action generation. At present, there are several main ways to achieve fine-grained skeleton-based action generation. In this work, we utilize a generative adversarial network with in-betweening, in order to generate natural and continuous skeleton sequences and better capture complex motion details. In-betweening can be viewed as a prediction task based on the past and future context. Besides, it is convenient to control the result in a personalized way and combine the framework with other network structures to further improve the performance. In particular, two simple discriminators are applied on different timescales and LSTM serves as the foundation of the action generator because of its capability of effectively capturing long-term dependencies and processing sequence data of different lengths. The target noise added to the input of the generator can contribute to the robustness of the system and further improve the performance. Moreover, a novel Tai Chi dataset composed of fine-grained skeleton-based action data is created using high quality motion capture technology. The model is evaluated on two fine-grained skeleton-based datasets, LaFAN1 and Tai Chi, which contain common daily actions and professional sports actions respectively, and it achieves superior performance both qualitatively and quantitatively.

关键词： Hands Training Noise Generative adversarial networks Generators Robustness Motion capture Skeleton Long short term memory Sports

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A Reinforcement Learning Solution to the Nonlinear Spacecraft Pursuit-Evasion Game Problem

A Reinforcement Learning Solution to the Nonlinear Spacecraf...

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IEEE International Conference on Cyber technology in Automation, control, and Intelligent Systems

作者： Haoqi Huang Guangtao Ran Yueyong Lyu Guangfu Ma Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798331506056

ISBN: (纸本)9798331506063

The pursuit-evasion game of non-cooperative spacecrafts under nonlinear dynamics is currently a hot topic in orbital gaming. We describe the above pursuit-evasion game model using differential game theory, transforming the gaming problem into a bilateral optimal control problem. Using elliptical orbit line-of-sight (LOS) dynamics with simple field-of-view constrains as the system model, we solve the Nash equilibrium solution for the two-body pursuit-evasion under the assumption of complete information. Due to the difficulty in obtaining analytical solutions for the Nash equilibrium, we adopt a reinforcement learning (RL)-based adaptive dynamic programming method. We obtain the approximate Nash equilibrium solution with RL method eventually and provide a successful simulation example.

关键词： Space vehicles Optimal control Line-of-sight propagation Games Reinforcement learning Differential games Nash equilibrium Orbits Nonlinear dynamical systems Dynamic programming

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Analytical Solution for the Reissner-Sagoci Problem of a Piezoelectric Half-Space

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Acta Mechanica Solida Sinica 2024年第3期37卷 363-370页

作者： Keqiang Hu Cun-Fa Gao Zengtao Chen Zheng Zhong State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Department of Mechanical Engineering University of AlbertaEdmontonABT6G 1H9Canada School of Science Harbin Institute of TechnologyShenzhen518055China

In this paper,a transversely isotropic piezoelectric half-space with the isotropy axis parallel to the z-axis is considered under rotation on a rigid circular disk bonded to the surface of the piezoelectric *** is a type of Reissner-Sagoci mixed boundary value *** utilizing the Hankel transform,the mixed boundary value problem is simplified into solving a pair of dual integral ***-field analytical expressions for displacement,stresses,and electric displacement inside the half-space are *** shear stresses and electric displacement on the surface are found to be singular at the edge of the rigid circular disk,and the stress intensity factors and electric displacement intensity factor are *** results show that material properties and geometric size have significant effects on displacement,shear stresses,and electric displacement.

关键词： Piezoelectric half-space Circular disk Reissner-Sagoci problem Stress intensity factor Electric displacement intensity factor

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Fault-tolerant control of Variable Load Drone Based on HOFA System Approach

Fault-tolerant Control of Variable Load Drone Based on HOFA ...

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International Symposium on Computer Science and Intelligent controls (ISCSIC)

作者： Runze Wang Ruizhi Tong Linjie Li Yi Zeng Department of Control Sciences and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9798350380286

ISBN: (纸本)9798350380293

This paper proposes an integral sliding controller based on second-order fully actuated system theory for the control problem of variable load six rotor unmanned aerial vehicles in the event of flight faults, and an extended observer with model information is used to estimate and compensate for the fault signals which occur during the flight. This paper innovatively introduces virtual control variables to supplement the system into a second-order six dimensional fully actuated system, and designs an integral sliding mode controller using a modified saturation function to achieve rapid stability of unmanned aerial vehicles during the process of verying load. In addition, the extended observer can also successfully estimate and compensate for the loss of execution efficiency of the drone.

关键词： Fault tolerance Fault tolerant systems Observers Autonomous aerial vehicles Stability analysis Vehicle dynamics Sliding mode control Drones Load modeling Aerospace control

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Hyperparameter Optimization of Object Detection Networks Based on Large Language Models

Hyperparameter Optimization of Object Detection Networks Bas...

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Annual Conference of Industrial Electronics Society

作者： Yushuo Hu Qiang Wang Department of Control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (数字)9781665464543

ISBN: (纸本)9781665464550

Abstract: Since the emergence of deep learning, the configuration of hyperparameters has been one of the most significant problems that people have paid attention to. However, traditional hyperparameter optimization techniques typically have drawbacks such as expensive calculation consumption and lengthy training time. With the development of large language models (LLMs), particularly models such as generative pre-trained transformer (GPT), it is achievable to utilize the models’ analysis ability to guide parameter space search. This paper investigates the use of LLMs for hyperparameter optimization in machine learning problems. To evaluate the effectiveness of this strategy, four object detection models, including YOLOv5, YOLOv8, Faster R-CNN, and R-FCN, were used to conduct experiments. At the same time, we compared the distinctions between this approach and traditional ways. The experimental results indicate that combining LLMs with the hyperparameter optimization process can perform comparably or better than conventional methods.

关键词： YOLO Deep learning Training Analytical models Neural networks Hyperparameter optimization Transformers Neural architecture search Optimization Information analysis

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