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Development of a next-generation closed-loop precision system:multiscale engineered nanocomposite hydrogel microneedles
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作者 Fance Meng Mengru Fang +5 位作者 Xinyu Liu Ruoyao Yu Miaomiao Yuan Shaoqing Feng Kan Wang Jinhong Guo 《Bio-Design and Manufacturing》 2026年第2期266-291,I0005,共27页
Microneedle technology has undergone a paradigm shift from basic transdermal drug delivery to intelligent,closed-loop theranostic systems.Hydrogel materials have emerged as core carriers due to their excellent biocomp... Microneedle technology has undergone a paradigm shift from basic transdermal drug delivery to intelligent,closed-loop theranostic systems.Hydrogel materials have emerged as core carriers due to their excellent biocompatibility,efficient drug loading capacity,and improved patient compliance.Moreover,critical bottlenecks in hydrogel microneedles,including poor mechanical strength,burst release of drugs,and delayed response to treatment,can be addressed via cross-scale integration of nanomaterials.This review systematically outlines several multiscale engineering strategies to overcome these limitations.The construction of nanotopological networks coupled with dynamic crosslinking modulation synergistically enhances the mechanical properties,stability of drug loading,and conductivity of hydrogel microneedles.Furthermore,responsive nanocarriers equipped with biosensors help establish a closed-loop linkage between monitoring and therapeutic functions.We highlight their synergistic theranostic advantages in scenarios such as wound regulation and tumor-immune microenvironments,while revealing the role in integrating flexible electronics with wearable systems in intelligent medicine.We also summarize the research advances on the biosafety and scalable manufacturing processes of nanocomposite hydrogel m icroneedles(NHMNs),providing examples of clinical translation to elucidate the path from fundamental research to industrial implementation.As a convergence of nanotechnology,biomaterials,and flexible electronics,NHMNs provide new standards for transdermal theranostics as well as a roadmap for iterative advancement of intelligent theranostic devices in personalized medicine.Their cross-scale collaborative design,which spans from the properties of materials to the functional integration of macroscopic devices,can facilitate potential breakthroughs in next-generation closed-loop theranostic systems. 展开更多
关键词 MICRONEEDLES Hydrogel NANOMATERIALS Transdermal drug delivery closed-loop theranostic system
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基于multibody的简摆颚式碎矿机建模与仿真
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作者 訾佼佼 《西安交通工程学院学术研究》 2025年第1期14-18,共5页
为响应教育部新工科建设指南要求,以机械工程类专业《机械原理》为切入点,提出将仿真法应用至实践教学。以简摆颚式碎矿机为研究对象,首先对其工作原理进行分析,然后分别利用解析法、矢量方程图解法和基于Matlab/Multibody仿真法对其建... 为响应教育部新工科建设指南要求,以机械工程类专业《机械原理》为切入点,提出将仿真法应用至实践教学。以简摆颚式碎矿机为研究对象,首先对其工作原理进行分析,然后分别利用解析法、矢量方程图解法和基于Matlab/Multibody仿真法对其建模并进行动力学分析,最后将三种分析方法及所得结果进行对比。结果表明:基于Matlab/Multibody仿真方法建模简捷、操作方便且仿真结果与解析法和图解法计算结果基本一致。该分析方法有利于提高大学生工程实践能力,为新工科背景下《机械原理》课程教学改革提供新思路,为机械工程类专业新工科建设奠定理论基础。 展开更多
关键词 新工科 碎矿机 multibody 运动分析 仿真
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Soft sensory-neuromorphic system for closed-loop neuroprostheses
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作者 Jaehyon Kim Sungjun Lee +1 位作者 Jiyong Yoon Donghee Son 《International Journal of Extreme Manufacturing》 2025年第4期2-33,共32页
Prosthetic devices designed to assist individuals with damaged or missing body parts have made significant strides,particularly with advancements in machine intelligence and bioengineering.Initially focused on movemen... Prosthetic devices designed to assist individuals with damaged or missing body parts have made significant strides,particularly with advancements in machine intelligence and bioengineering.Initially focused on movement assistance,the field has shifted towards developing prosthetics that function as seamless extensions of the human body.During this progress,a key challenge remains the reduction of interface artifacts between prosthetic components and biological tissues.Soft electronics offer a promising solution due to their structural flexibility and enhanced tissue adaptability.However,achieving full integration of prosthetics with the human body requires both artificial perception and efficient transmission of physical signals.In this context,synaptic devices have garnered attention as next-generation neuromorphic computing elements because of their low power consumption,ability to enable hardware-based learning,and high compatibility with sensing units.These devices have the potential to create artificial pathways for sensory recognition and motor responses,forming a“sensory-neuromorphic system”that emulates synaptic junctions in biological neurons,thereby connecting with impaired biological tissues.Here,we discuss recent developments in prosthetic components and neuromorphic applications with a focus on sensory perception and sensorimotor actuation.Initially,we explore a prosthetic system with advanced sensory units,mechanical softness,and artificial intelligence,followed by the hardware implementation of memory devices that combine calculation and learning functions.We then highlight the importance and mechanisms of soft-form synaptic devices that are compatible with sensing units.Furthermore,we review an artificial sensory-neuromorphic perception system that replicates various biological senses and facilitates sensorimotor loops from sensory receptors,the spinal cord,and motor neurons.Finally,we propose insights into the future of closed-loop neuroprosthetics through the technical integration of soft electronics,including bio-integrated sensors and synaptic devices,into prosthetic systems. 展开更多
关键词 soft electronics synaptic devices sensory-neuromorphic system closed-loop neuroprosthetics
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A study of mechanism-data hybrid-driven method for multibody system via physics-informed neural network
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作者 Ningning Song Chuanda Wang +1 位作者 Haijun Peng Jian Zhao 《Acta Mechanica Sinica》 2025年第3期129-153,共25页
Numerical simulation plays an important role in the dynamic analysis of multibody system.With the rapid development of computer science,the numerical solution technology has been further developed.Recently,data-driven... Numerical simulation plays an important role in the dynamic analysis of multibody system.With the rapid development of computer science,the numerical solution technology has been further developed.Recently,data-driven method has become a very popular computing method.However,due to lack of necessary mechanism information of the traditional pure data-driven methods based on neural network,its numerical accuracy cannot be guaranteed for strong nonlinear system.Therefore,this work proposes a mechanism-data hybrid-driven strategy for solving nonlinear multibody system based on physics-informed neural network to overcome the limitation of traditional data-driven methods.The strategy proposed in this paper introduces scaling coefficients to introduce the dynamic model of multibody system into neural network,ensuring that the training results of neural network conform to the mechanics principle of the system,thereby ensuring the good reliability of the data-driven method.Finally,the stability,generalization ability and numerical accuracy of the proposed method are discussed and analyzed using three typical multibody systems,and the constrained default situations can be controlled within the range of 10^(-2)-10^(-4). 展开更多
关键词 Mechanism-data hybrid-driven method Differential-algebra equation multibody system Physics-informed neural network
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Design and Implementation of Closed-Loop Control of Vector Force in Static Push-the-bit Rotary Steering System
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作者 Liang Yao Kang Hong-bo +4 位作者 Liu Yue Chen wen Sun Yan Ma Li Zhao Yan-Wei 《Applied Geophysics》 2025年第3期796-803,896,共9页
Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the p... Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the pushing force acting on the wellbore in different sizes and directions within a circular range,ultimately allowing the wellbore trajectory to be drilled in a predetermined direction.By analyzing its mathematical principles and the actual characteristics of the instrument,a vector force closed-loop control method,including steering and holding modes,was designed.The adjustment criteria for the three hydraulic modules are determined to achieve rapid adjustment of the vector force.The theoretical feasibility of the developed method was verified by comparing its results with the on-site application data of an imported rotary guidance system. 展开更多
关键词 Static push-the-bit hydraulic modules closed-loop control vector force working mode
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Optimized PID neural network closed-loop control for basal ganglia network in Parkinson's disease
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作者 Hengxi Zhang Honghui Zhang +1 位作者 Shuang Liu Lin Du 《Chinese Physics B》 2025年第12期193-206,共14页
Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse ... Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse effects and causing excessive energy consumption.In this paper,we present an adaptive closed-loop framework integrating a Yogi-optimized proportional–integral–derivative neural network(Yogi-PIDNN)controller.The Yogi-augmented gradient adaptation mechanism accelerates the convergence of general PIDNN controllers in high-dimensional nonlinear control systems while reducing control energy usage.In addition,a system identification method establishes input–output dynamics for pre-training stimulation waveforms,bypassing real-time parameter-tuning constraints and thereby enhancing closed-loop adaptability.Finally,a theoretical analysis based on Lyapunov stability criteria establishes a sufficient condition for closed-loop stability within the identified model.Computational validations demonstrate that our approach restores thalamic relay reliability while reducing energy consumption by(81.0±0.7)%across multi-frequency tests.This study advances adaptive neuromodulation by synergizing data-driven pre-training with stability-guaranteed real-time control,offering a novel framework for energy-efficient and personalized Parkinson's therapy. 展开更多
关键词 Parkinson's disease closed-loop deep brain stimulation PID neural network adaptive control
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Kalman filter based state estimation for the flexible multibody system described by ANCF
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作者 Zuqing Yu Shuaiyi Liu Qinglong Tian 《Acta Mechanica Sinica》 2025年第5期207-218,共12页
The state estimation of the flexible multibody systems is a vital issue since it is the base of effective control and condition monitoring.The research on the state estimation method of flexible multibody system with ... The state estimation of the flexible multibody systems is a vital issue since it is the base of effective control and condition monitoring.The research on the state estimation method of flexible multibody system with large deformation and large rotation remains rare.In this investigation,a state estimator based on multiple nonlinear Kalman filtering algorithms was designed for the flexible multibody systems containing large flexibility components that were discretized by absolute nodal coordinate formulation(ANCF).The state variable vector was constructed based on the independent coordinates which are identified through the constraint Jacobian.Three types of Kalman filters were used to compare their performance in the state estimation for ANCF.Three cases including flexible planar rotating beam,flexible four-bar mechanism,and flexible rotating shaft were employed to verify the proposed state estimator.According to the different performances of the three types of Kalman filter,suggestions were given for the construction of the state estimator for the flexible multibody system. 展开更多
关键词 Nonlinear Kalman filter Absolute nodal coordinate formulation Flexible multibody system dynamics State estimation
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Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
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作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
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丘陵山地马铃薯收获机履带底盘系统性能试验研究
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作者 梁素明 梁晋雄 +2 位作者 霍利光 王慧杰 钟煊童 《农机化研究》 北大核心 2026年第5期273-280,共8页
针对丘陵山地复杂地形中马铃薯等根茎类收获机械化程度低、现有大型机械适应性差等问题,设计了一种适用于黏重红壤地形的自走式联合收获机履带底盘系统,并对其行驶通过性能进行多维度研究。首先,通过理论力学模型分析了底盘在纵坡、横... 针对丘陵山地复杂地形中马铃薯等根茎类收获机械化程度低、现有大型机械适应性差等问题,设计了一种适用于黏重红壤地形的自走式联合收获机履带底盘系统,并对其行驶通过性能进行多维度研究。首先,通过理论力学模型分析了底盘在纵坡、横坡和沟壑等典型工况下受力特性,以及抗侧翻临界条件,得到底盘关键设计参数为履带宽度400 mm、接地长度1660 mm,采用静液压传动(HST)以提高动态控制能力;然后,基于RecurDyn多体动力学软件构建虚拟样机模型,结合黏土环境参数(内聚力6.895×10^(-2)kPa、抗剪角34°)进行仿真分析,结果表明:底盘可稳定跨越700 mm沟壑、翻越200 mm田埂,并实现了30°纵坡与25°横坡爬升,无倾覆现象;最后,进行田间试验,样机在平均坡度为15.95°的纵坡和600 mm沟壑地形中表现出色,俯仰角变化与仿真趋势一致,验证了理论模型的可靠性。研究通过“理论-仿真-试验”闭环验证,解决了丘陵山地作业场景下底盘通过性与转向稳定性难题,同时可为马铃薯等收获机械底盘设计提供技术参考。 展开更多
关键词 马铃薯收获机 履带底盘 通过性分析 多体动力学仿真
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挂索机构几何形状对火箭网系回收动力学的影响
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作者 张欢 阚镭 +2 位作者 周立梁 陈彤 宋晓东 《机械工程学报》 北大核心 2026年第1期216-228,共13页
提出了一种基于二维符号距离场(Signed distance filed,SDF)的柔性绳索与轴向拉伸刚体精准高效接触检测方法,用于火箭网系回收系统中挂索机构与拦阻索的摩擦接触动力学计算,分析挂索机构几何形状对回收动力学的影响。利用轴向拉伸型物... 提出了一种基于二维符号距离场(Signed distance filed,SDF)的柔性绳索与轴向拉伸刚体精准高效接触检测方法,用于火箭网系回收系统中挂索机构与拦阻索的摩擦接触动力学计算,分析挂索机构几何形状对回收动力学的影响。利用轴向拉伸型物体的几何特点,将柔性绳索与具有复杂几何形状的轴向拉伸刚体之间的接触检测问题转换为二维问题。由SDF精准表征截面形状,通过离线生成高精度SDF和法线场,在线双三次插值接触参数计算,实现精准高效摩擦接触动力学计算,所提接触检测方法通过圆柱与绳索的接触动力学仿真和试验验证了准确性。针对捕获火箭的拦阻索入钩过程,建立了挂索机构与拦阻索系统多体动力学模型并针对不同的挂索机构几何形状进行了仿真计算,结果表明挂索机构截面几何形状直接影响挂索机构与拦阻索局部摩擦接触细节,特别在触网时刻,大圆角截面形状能有效降低触网冲击作用。 展开更多
关键词 符号距离场 任意拉格朗日欧拉法 挂索机构 摩擦接触 多体系统动力学
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航天器在轨操作过程柔性体碰撞动力学建模
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作者 葛东明 鄂薇 +5 位作者 邹元杰 邓润然 关晓东 柳翠翠 张志娟 宫伟伟 《航天器环境工程》 2026年第1期17-24,共8页
针对航天器在轨操作过程中柔性多体系统的接触碰撞动力学建模与系统仿真需求,提出一种柔性多体接触碰撞动力学建模方法,用以刻画冲击能量在结构振动与接触碰撞过程中的产生、传递与耗散动力学行为。所建立的动力学方程适用于任意线性小... 针对航天器在轨操作过程中柔性多体系统的接触碰撞动力学建模与系统仿真需求,提出一种柔性多体接触碰撞动力学建模方法,用以刻画冲击能量在结构振动与接触碰撞过程中的产生、传递与耗散动力学行为。所建立的动力学方程适用于任意线性小变形结构及凸几何形状,具有良好的结构动力学模型与几何模型通用性,能够实现多面、多点接触碰撞检测,更符合实际物理过程。通过将柔性体接触碰撞动力学方程与柔性多体动力学方程耦合,构建了统一的仿真模型,可用于空间目标在轨抓捕、空间结构在轨组装等典型航天器在轨操作任务的总体方案设计与系统仿真验证。 展开更多
关键词 航天器 在轨操作 柔性多体系统 接触碰撞 动力学建模
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Three Dimensional Kinematics Analysis of the Independent Suspension Multibody System 被引量:2
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作者 陈欣 林逸 +1 位作者 孙大刚 白文辉 《Journal of Beijing Institute of Technology》 EI CAS 1997年第4期80-86,共7页
Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce t... Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce the number of the generalized coordinates and constraint functions. By solving the nonlinear equations, the motion of any points in the whole suspension and wheel system can be predicted, including the spatial changes of the wheel alignment parameters which are of great importance to the car performances. 展开更多
关键词 independent suspension three dimension kinematic analysis multibody system
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Multibody System Dynamics Analysis for Valve Trains 被引量:3
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作者 覃文洁 左正兴 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期375-379,共5页
The theory of multibody system dynamics is used to simulate valve trains' kinematics and dynamics characteristics, and the methods of establishing and analyzing the multibody system dynamics model for valve trains... The theory of multibody system dynamics is used to simulate valve trains' kinematics and dynamics characteristics, and the methods of establishing and analyzing the multibody system dynamics model for valve trains are discussed. Since most of the flexible bodies of a valve train are slender parts, the finite segment method is used to build their models. Other parts such as cams, valve heads etc., are built as rigid bodies. After applying the constraints, forces and motions, the establishing of the whole system is accomplished, and the Lagrange's multiplier method can be used to obtain its dynamics constitutive equations. As an example, a valve trains multibody system model of 4100QB engine made by the Yunnan Internal Combustion Engine Limited Liability Company is established, and the analysis results obtained show that its working performance is generally good except that the air pass ability and the lubrication effect of the cam and the tappet have to be improved. 展开更多
关键词 valve train multibody system DYNAMICS
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基于Simscape Multibody的SCARA机器人建模与运动控制仿真 被引量:3
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作者 张卓 冯海杰 邓振杰 《科技创新与应用》 2022年第13期64-67,共4页
针对SCARA机器人的运动控制仿真问题,利用Simscape Multibody建立SCARA机器人动力学仿真模型。此模型具备一定的通用性,集成机器人轨迹规划模块、控制器模块以及仿真数据采集接口,可以为SCARA机器人轨迹规划和运动控制算法提供开源研发... 针对SCARA机器人的运动控制仿真问题,利用Simscape Multibody建立SCARA机器人动力学仿真模型。此模型具备一定的通用性,集成机器人轨迹规划模块、控制器模块以及仿真数据采集接口,可以为SCARA机器人轨迹规划和运动控制算法提供开源研发平台。通过动态仿真验证该模型有效性。 展开更多
关键词 SCARA MATLAB Simscape multibody 动力学建模
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某电动轮动力总成振动响应分析
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作者 李洪玉 孙登科 +2 位作者 吴佩宝 张鹏 侯之超 《振动工程学报》 北大核心 2026年第3期735-742,共8页
电动轮动力总成的振动特性直接影响轮毂驱动车辆的操控性和乘坐舒适性。本文针对某具有NW行星轮系的电动轮动力总成,基于多体动力学模型,开展仿真计算,分析不同工况下由径向电磁力、转矩脉动和齿轮传递误差等多种激励引起的动力总成壳... 电动轮动力总成的振动特性直接影响轮毂驱动车辆的操控性和乘坐舒适性。本文针对某具有NW行星轮系的电动轮动力总成,基于多体动力学模型,开展仿真计算,分析不同工况下由径向电磁力、转矩脉动和齿轮传递误差等多种激励引起的动力总成壳体的振动响应。建立了动力总成的刚柔耦合多体动力学模型,计算了行星轮系高速级和低速级齿轮副的传递误差。基于驱动电机的电磁有限元模型,计算了电机的径向电磁力和转矩脉动。分析了激励中幅值较大的各阶谐波单独作用,以及三种激励同时加载时动力总成壳体的振动响应。结合动力总成稳态工况的振动台架试验,对该电动轮的振动特性进行了讨论。结果表明,行星轮系高速级和低速级的齿轮传递误差是引起该电动轮动力总成壳体振动的主要激励源。 展开更多
关键词 电动轮动力总成 多体动力学 多源激励 振动特性 振动响应
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无尾翼弹外弹道与姿态联合仿真
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作者 孙舒洋 邵伟平 郝永平 《一重技术》 2026年第1期49-53,42,共6页
基于经典外弹道理论,在弹道仿真过程中,首先从动力学角度建立弹体外弹道数学模型;在MATLAB中,依据给定的初始发射条件(如初速、射角、质量等),采用四阶龙格—库塔法进行数值积分,求解质心运动轨迹。为进一步获取弹体在飞行过程中各时刻... 基于经典外弹道理论,在弹道仿真过程中,首先从动力学角度建立弹体外弹道数学模型;在MATLAB中,依据给定的初始发射条件(如初速、射角、质量等),采用四阶龙格—库塔法进行数值积分,求解质心运动轨迹。为进一步获取弹体在飞行过程中各时刻的姿态响应,将MATLAB计算所得的轨迹数据导入多体动力学软件ADAMS。在ADAMS中,施加气动力、阻尼力矩及陀螺效应等关键载荷,并设置相应约束与驱动,开展六自由度姿态仿真。由此可精确获得弹体在整个飞行过程中的姿态角、攻角及轨迹参数,进而分析攻角动态变化对弹体飞行稳定性的影响。 展开更多
关键词 外弹道 多体动力学仿真 龙格—库塔算法
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海上风力机单叶片吊装对接气弹耦合振动特性分析
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作者 张奇夫 夏鸿建 +1 位作者 林芝标 李德源 《现代农业装备》 2026年第1期101-109,共9页
海上风力机正朝着大型化和深远海快速发展,伴随叶片尺寸不断增大,超长柔性叶片在吊装对接过程中气动载荷与弹性变形互相耦合,加剧了叶片振动,从而影响叶片对接安装精度。为分析超长柔性叶片海上吊装对接的气弹耦合振动特性,采用超级单... 海上风力机正朝着大型化和深远海快速发展,伴随叶片尺寸不断增大,超长柔性叶片在吊装对接过程中气动载荷与弹性变形互相耦合,加剧了叶片振动,从而影响叶片对接安装精度。为分析超长柔性叶片海上吊装对接的气弹耦合振动特性,采用超级单元法建立叶片的非线性结构模型,通过弹簧-刚体法建立钢丝绳动力学模型,并由叶素动量理论结合IAG动态失速模型构建非定常气动载荷,以参数传递的弱耦合方式,建立叶片吊装的气弹耦合模型。以DTU大型风力机叶片为吊装对象,在恒定风、湍流风和阵风等风况下,分析吊装叶片的气弹耦合振动特性,为海上风力机叶片高效、高精安装提供理论指导。 展开更多
关键词 海上风力机 叶片吊装 多体动力学 气弹耦合
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单作动控制的起落架收放系统设计与分析
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作者 李福 蒙杰 +2 位作者 王天池 张紫建 豆清波 《科学技术与工程》 北大核心 2026年第6期2636-2644,共9页
随着无人机向长航时、高载荷、小型化方向快速发展,起落架的轻量化与结构简化需求日益迫切。设计了一套基于单作动筒控制收放和锁止的起落架收放系统。该系统通过单作动筒集成收放驱动与锁止功能,有效降低了起落架结构重量与复杂度。采... 随着无人机向长航时、高载荷、小型化方向快速发展,起落架的轻量化与结构简化需求日益迫切。设计了一套基于单作动筒控制收放和锁止的起落架收放系统。该系统通过单作动筒集成收放驱动与锁止功能,有效降低了起落架结构重量与复杂度。采用CATIA软件完成三维参数化建模与运动学仿真,验证了收放结构的可行性与机构干涉特性;基于LMS Virtual Lab Motion平台建立了多体动力学模型,分析了收放过程中作动筒载荷特性并对其结构强度进行评估计算。此外,通过着陆冲击仿真,评估了起落架系统在着陆冲击载荷下的动态响应特性,结果表明该系统能够有效吸收冲击能量并满足结构强度要求。最后通过实验验证了机构设计的可靠性以及运动学与动力学仿真的有效性。该研究在保证机构功能可靠性的同时有效降低了系统的重量,为无人机起落架轻量化设计提供了工程参考。 展开更多
关键词 无人机 起落架 单作动筒 收放系统 多体动力学
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双立柱堆垛机刚柔耦合动力学仿真及分析
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作者 张恒 黄兴元 +1 位作者 项肇 高立 《南昌大学学报(工科版)》 2026年第1期102-108,共7页
双立柱堆垛机在存取货物过程中,加速和减速阶段容易引起立柱及载货台产生结构振动,导致堆垛机的运行稳定性降低。由于堆垛机的金属框架长细比较大,属于柔性体,首先利用ABAQUS软件计算金属框架的结构模态并进行柔性化处理,然后通过与ADAM... 双立柱堆垛机在存取货物过程中,加速和减速阶段容易引起立柱及载货台产生结构振动,导致堆垛机的运行稳定性降低。由于堆垛机的金属框架长细比较大,属于柔性体,首先利用ABAQUS软件计算金属框架的结构模态并进行柔性化处理,然后通过与ADAMS联合建模,建立了堆垛机的刚柔耦合动力学模型。为了改善堆垛机在提升过程中的动力学性能,提出一种加速度无突变且连续的三角函数加减速曲线,与传统抛物线型速度曲线相比可控性更强,可以充分发挥出堆垛机的加减速性能。结果表明:三角函数运行速度曲线加速度变化连续平滑,加速效率高,立柱的振动位移降低了66.83%,货物的振动问题也得到改善,提高了堆垛机的运行稳定性。 展开更多
关键词 堆垛机 刚柔耦合 多体动力学 速度曲线 振动特性
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A novel closed-loop vacuum silicon microgyroscope
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作者 夏敦柱 王寿荣 周百令 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期63-67,共5页
A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reach... A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reaches greater than l0 000. Self-oscillating and closed-loop methods based on electrostatic force feedback are adopted in both measure and control circuits. Both single side driving and sensing methods are used to simplify the drive circuit. These dual channel decomposition and reconstruction closed loops are applied in sense modes. The testing results demonstrate that useful signals and guadrature signals do not interact with each other because of the decoupling of their phases. Under the condition of a scale factor of 9. 6 mV/((°) .s), in a full measurement range of±300 (°)/s, the zero bias stability reaches 28 (°)/h with a nonlinear coefficient of 400 × 10^-6 and a simulated bandwidth of more than 100 Hz. The overall performance is improved by two orders of magnitude in comparison to that at atmospheric pressure. 展开更多
关键词 silicon micro-gyroscope (SMG) self oscillating dual-channel closed-loop detection scale factor zero bias stability
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