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Chinese Journal of Aeronautics 2024年第3期37卷 417-439页

作者： dongyang shang Xiaopeng LI Meng YIN Fanjie LI School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(SFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(SMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the SFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the SFMUH.

关键词： Space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

Vibration suppression for rotating space slender flexible structures based on novel deformation description and NNSMC controller with hyperbolic tangent function

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Chinese Journal of Aeronautics 2024年第10期37卷 339-364页

作者： dongyang shang Xiaopeng LI Men YIN Sainan ZHOU School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

Rotating Space Slender Flexible Structures(RSSFS)are extensively utilized in space operations because of their light weight,mobility,and low energy *** realize the accurate space operation of the RSSFS,it is necessary to establish a precise mechanical model and develop a control algorithm with high ***,with the application of traditional control strategies,the RSSFS often suffers from the chattering phenomenon,which will aggravate structure *** this paper,novel deformation description is put forward to balance modeling accuracy and computational efficiency of the RSSFS,which is better appropriate for real-time ***,the Neural Network Sliding Mode Control(NNSMC)strategy modified by the hyperbolic tangent(tanh)function is put forward to compensate for modeling errors and reduce the chattering phenomenon,thereby improving the trajectory tracking accuracy of the ***,a mathematical model for the RSSFS is developed according to the novel deformation description and the vibration theory of flexible *** of the deformation accuracy between different models proves that the novel modeling method proposed has high modeling ***,the universal approximation property of the Radial Basis Function(RBF)neural network is put forward to determine and compensate for modeling errors,which consist of higher-order modes and the uncertainties of external *** addition,the tanh function is proposed as the reaching law in the conventional NNSMC strategy to suppress driving torque *** control law of modified NNSMC strategy and the adaptive law of weight coefficients are developed according to the Lyapunov theorem to guarantee the RSSFS ***,the simulation and physical experimental tests of the RSSFS with different control strategies are *** results show that the control law according to the novel deformation description and the modified NNSMC strategy can obta

关键词： Space slender flexible structure Novel deformation description RBF neural network Vibration suppression Hyperbolic tangent function

采用模糊补偿滑模控制器的空间柔性机械臂振动抑制方法

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振动与冲击 2024年第7期43卷 175-185,204页

作者：尚东阳李小彭尹猛李凡杰周赛男东北大学机械工程与自动化学院沈阳110819 中国科学院深圳先进技术研究院广东深圳518055

空间柔性机械臂可以安装于空间站协助宇航员开展在轨维修、航天器交会对接和太空垃圾捕获等任务。空间柔性机械臂因其细长的结构在运动过程中会出现振动现象,进而影响操作精度和飞行安全。为了减弱空间柔性机械臂的振动,采用模糊补偿滑... 详细信息

空间柔性机械臂可以安装于空间站协助宇航员开展在轨维修、航天器交会对接和太空垃圾捕获等任务。空间柔性机械臂因其细长的结构在运动过程中会出现振动现象,进而影响操作精度和飞行安全。为了减弱空间柔性机械臂的振动,采用模糊补偿滑模控制策略对空间柔性机械臂的旋转运动进行控制。通过提高空间柔性机械臂的转动控制精度间接地减弱振动。首先根据假设模态法描述空间柔性机械臂的变形,使用拉格朗日原理建立了考虑了二维变形的模态和转角耦合的动力学方程。然后,利用模糊规则的万能逼近特性辨识、补偿包括柔性非线性项和外界干扰的动力学模型的不确定成分。接下来,根据李雅普诺夫函数设计模糊补偿滑模控制策略的控制律和自适应律以保证空间柔性机械臂的闭环稳定性。最后,开展了空间柔性机械臂的仿真和物理样机控制试验。试验结果表明,模糊补偿滑模控制策略可以有效地提高空间柔性机械臂的转动控制精度,间接地减弱振动幅值。与传统的滑模控制策略相比,提出的控制策略可以使转角跟踪误差绝对值的平均值下降17.86%,使横向加速度的标准差下降31.91%。

关键词：空间柔性机械臂滑模控制模糊补偿振动抑制

Rotation Angle Control Strategy for Telescopic Flexible Manipulator Based on a Combination of Fuzzy Adjustment and RBF Neural Network

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 203-226页

作者： dongyang shang Xiaopeng Li Meng Yin Fanjie Li Bangchun Wen School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

The length of fexible manipulators with a telescopic arm alters during *** dynamic parameters of telescopic fexible manipulators exhibit signifcant time-varying characteristics owing to variations in *** an increase in the manipulators’length,the nonlinear terms caused by fexibility in the manipulators’dynamic equations cannot be *** time-varying characteristics and nonlinear terms of telescopic fexible manipulators cause fuctuations in rotation angles,which afect the operation accuracy of *** this study,a control strategy based on a combination of fuzzy adjustment and an RBF neural network is utilized to improve the control accuracy of fexible telescopic ***,the dynamic equation of the manipulators is established using the assumed mode method and Lagrange’s principle,and the infuence of nonlinear terms is ***,a combined control strategy is proposed to suppress the fuctuation of the rotation angle in telescopic fexible *** variation ranges of the feedforward PD controller parameters are determined by the pole placement strategy and length of the *** rules are utilized to adjust the controller parameters in *** RBF neural network is utilized to identify and compensate the uncertain part of the dynamic model of the fexible *** uncertain part comprises time-varying parameters and nonlinear ***,numerical simulations and prototype experiments prove the efectiveness of the combined control *** results prove that the proposed control strategy has a smaller standard deviation of ***,the combined control strategy is more suitable for telescopic fexible manipulators,which can efectively improve the control accuracy of rotation angles.

关键词： Flexible manipulator RBF neural network Fuzzy control Dynamic uncertainty

Inhibition of SLC26A4 regulated by electroacupuncture suppresses the progression of myocardial ischemia-reperfusion injury

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BIOCELL 2024年第4期48卷 665-675页

作者： FEI KONG QIYUAN TIAN BINGLIN KUANG LILI shang XIAOXIAO ZHANG dongyang LI YING KONG Department of Endocrinology Heilongjiang University of Chinese MedicineHarbin150040China Department of Cardiology Heilongjiang University of Chinese MedicineHarbin150040China College of Clinical Medicine Heilongjiang University of Chinese MedicineHarbin150040China Department of Nephrology Beijing Hospital of Integrated Traditional Chinese and Western MedicineBeijing100039China College of Acupuncture and Massage Heilongjiang University of Chinese MedicineHarbin150040China Department of Acupuncture Heilongjiang University of Chinese MedicineHarbin150040China

Introduction:Myocardial ischemia-reperfusion(IR)injury has received widespread attention due to its damaging ***(EA)pretreatment has preventive effects on myocardial IR ***26A4 is a Na+independent anion reverse transporter and has not been reported in myocardial IR ***:Toﬁnd potential genes that may be regulated by EA and explore the role of this gene in myocardial IR ***:RNA sequencing and bioinformatics analysis were performed to obtain the differentially expressed genes in the myocardial tissue of IR rats with EA *** infarction size was detected by TTC *** CK,creatinine kinase-myocardial band,Cardiac troponin I,and lactate dehydrogenase levels were determined by *** effect of SLC26A4 on cardiomyocyte apoptosis was explored by TUNEL staining and western *** effects of SLC26A4 on inﬂammation were determined by HE staining,ELISA,and real-time *** effect of SLC26A4 on the NF-κB pathway was determined by western ***:SLC26A4 was up-regulated in IR rats but downregulated in IR rats with EA *** with IR rats,those with SLC26A4 knockdown exhibited improved cardiac function according to decreased myocardial infarction size,reduced serum LDH/CK/CK-MB/cTnI levels,and elevated left ventricular ejection fraction and fractional ***26A4 silencing inhibited myocardial inﬂammation,cell apoptosis,phosphorylation,and nuclear translocation of NF-κB ***:SLC26A4 exhibited promoting effects on myocardial IR injury,while the SLC26A4 knockdown had an inhibitory effect on the NF-κB *** results further unveil the role of SLC26A4 in IR injury.

关键词： Myocardial ischemia Reperfusion SLC26A4 NF-κB pathway

Dynamic Modeling and Control of Inspection Robot Joint Drive System

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Dynamic Modeling and Control of Inspection Robot Joint Drive...

基于机械臂位姿变换的柔性负载伺服驱动系统控制策略

第三十九届中国控制会议

作者： Xiaopeng Li dongyang shang Yingnan Yang Junqiang Guo School of Mechanical Engineering and Automation Northeastern University

During crossing obstacles and inspecting lines, an inspection robot for extra-high voltage power transmission lines will appear the phenomenon of jitter. This phenomenon is related not only to the external wind load but also to the flexibility of the inspection robot joint drive system. To reduce the jitter in the process of crossing the obstacle and crossing the obstacle, the PI control strategy is adopted to control the inspection robot joint drive system in this paper. The value of inertia of the inspection robot joint drive system is closely related to the inertia matrix of the dynamic equation of the inspection robot. Firstly the inertia matrix of the inspection robot is obtained by applying the Lagrange dynamics equation. Then the dynamic model of the inspection robot joint drive system is established. Through the state equation, the transfer function of motor speed to electromagnetic torque can be obtained. Furthermore, the parameters of the PI controller are designed by pole assignment strategies with the identical damping coefficients. Finally, numerical simulation results show that the jitter of the inspection robot can be reduced by designing PI controller parameters.

关键词： Inspection robot Dynamic modeling PI control strategy

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机械工程学报 2020年第21期56卷 56-69页

作者：李小彭尚东阳陈仁桢闻邦椿东北大学机械工程与自动化学院沈阳110819

伺服驱动系统的柔性负载端转动惯量等参数随柔性机械臂位姿变化而变化,进而影响伺服驱动系统电动机输出端转速。为降低电动机输出端速度波动,采用极点配置的方法设计伺服驱动系统转速环PI控制器参数,该参数的选择随柔性机械臂位姿变化... 详细信息

伺服驱动系统的柔性负载端转动惯量等参数随柔性机械臂位姿变化而变化,进而影响伺服驱动系统电动机输出端转速。为降低电动机输出端速度波动,采用极点配置的方法设计伺服驱动系统转速环PI控制器参数,该参数的选择随柔性机械臂位姿变化而变化,从而使伺服驱动系统在不同位姿下获得良好的动态响应特性,避免机械谐振发生。首先根据连续体振动理论和拉格朗日原理建立了柔性负载伺服驱动系统动力学模型,并通过状态方程求得电动机转速到柔性负载驱动转矩的传递函数。将变参数PI控制策略应用于伺服驱动系统转速环控制中,分析了柔性负载对转速环的控制特性的影响,采用极点配置的方法设计控制器参数。接下来分别采用相同幅值、相同阻尼系数、相同实部3种极点配置策略设计控制器参数。讨论了这3种极点配置策略不同参数对系统谐振峰值、谐振频率和带宽的影响。最后通过数值仿真分析表明:伺服驱动系统等效柔性负载参数与机械臂的位姿有关;柔性负载回转半径、转动惯量较大的情况,不适宜使用相同实部的极点配置方法,但其余两种方法可通过适当选择参数使电动机输出转速波动程度减小。

关键词：柔性机械臂伺服驱动系统柔性负载 PI控制策略极点配置方法

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变刚度轴承-碰摩转子机动飞行动力学响应

哈尔滨工业大学学报 2020年第1期52卷 1-7页

作者：李小彭陈仁桢尚东阳陈延炜东北大学机械工程与自动化学院

为研究机动飞行状态下高速滚动轴承-转子耦合系统非线性动力学特性,利用有限元方法建立爬升-俯冲机动飞行状态下含滚动轴承时变刚度的轴承-碰摩转子系统数学模型,并利用Newmark-β积分法对系统动力学方程进行求解.模型中考虑了滚动轴承... 详细信息

为研究机动飞行状态下高速滚动轴承-转子耦合系统非线性动力学特性,利用有限元方法建立爬升-俯冲机动飞行状态下含滚动轴承时变刚度的轴承-碰摩转子系统数学模型,并利用Newmark-β积分法对系统动力学方程进行求解.模型中考虑了滚动轴承时变刚度与转子非线性动力学特性之间的相互影响,分析了转子偏心及滚动轴承径向间隙的影响.求解模型得到了系统在不同状态下的时域图、频域图及分岔图等,并以此为依据对高速滚动轴承刚度的时变特性、轴承刚度与转子动力学状态的相互影响、轴承-转子系统非线性特性、机动飞行状态对系统的影响及含碰摩故障的转子系统在机动飞行状态下的动力学响应进行了分析.研究结果表明:轴承刚度的时变特性与转子系统的动力学特性密切相关,是限制转子系统最高转速的因素之一;机动载荷会使转子系统产生复杂的非线性动力学特性,但当系统转速较低时,机动载荷的引入能一定程度上提高系统稳定性;随着碰摩刚度的增大,系统稳定运动区间减小.

关键词：转子动力学非线性动力学轴承时变刚度机动飞行爬升-俯冲状态

采用RBF神经网络辨识的柔性机械臂抑振控制策略

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西安交通大学学报 2022年第6期56卷 76-84页

作者：尚东阳李小彭尹猛李凡杰杨贺绪东北大学机械工程与自动化学院沈阳110819 中国科学院深圳先进技术研究院广东深圳518055

针对柔性机械臂在运动过程中受到柔性因素的影响会出现剧烈振动的问题,提出一种采用径向基(RBF)神经网络辨识的柔性机械臂抑振控制策略,通过减弱机械臂转角波动的方式间接抑制振动。首先,根据拉格朗日原理和假设模态法建立柔性机械臂的... 详细信息

针对柔性机械臂在运动过程中受到柔性因素的影响会出现剧烈振动的问题,提出一种采用径向基(RBF)神经网络辨识的柔性机械臂抑振控制策略,通过减弱机械臂转角波动的方式间接抑制振动。首先,根据拉格朗日原理和假设模态法建立柔性机械臂的动力学模型,其中的不确定项由模态坐标和转角耦合的非线性项构成;其次,在控制律的设计中采用RBF神经网络对动力学模型的不确定项进行辨识补偿,从而提高驱动力矩的精度;最后,通过调整神经网络权重自适应律的系数,使包含辨识结果的控制律满足李亚普诺夫稳定性定理,从而保证动力学系统的稳定性,其中权重自适应律由高斯函数和误差向量组成。采用柔性机械臂实物控制平台的对比实验结果表明:所提出的控制策略能够有效减小柔性机械臂的转角误差和振动幅值;当柔性机械臂长度为1.5 m时,相比常规比例微分控制策略,采用RBF神经网络辨识的控制策略使机械臂末端振动敏感方向的加速度的方差下降了5.8%。该控制策略为柔性机械臂的振动抑制提供了新思路。

关键词：柔性机械臂 RBF神经网络不确定项振动抑制非线性项

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某火烧桥桥梁承载能力评估及维修加固措施

山西建筑 2021年第17期47卷 128-130页

作者：商东洋辽宁省交通规划设计院有限责任公司辽宁沈阳110166

某桥梁由于通行车辆沥青泄漏,引发了该桥简支端附近产生大火,该桥上部结构、下部结构及桥面系均产生了较大损伤。对该桥进行近距离接触检测与荷载试验后,发现该桥第4孔、第5孔主梁边支点斜截面抗剪承载能力不满足设计荷载等级要求,无法... 详细信息

某桥梁由于通行车辆沥青泄漏,引发了该桥简支端附近产生大火,该桥上部结构、下部结构及桥面系均产生了较大损伤。对该桥进行近距离接触检测与荷载试验后,发现该桥第4孔、第5孔主梁边支点斜截面抗剪承载能力不满足设计荷载等级要求,无法满足安全通行的条件。因此通过增大截面的加固方法,使结构的承载能力得到提高,从而满足了原设计荷载和安全通行的要求。

关键词：桥梁荷载试验维修加固