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Robust adaptive precision motion control of tank horizontal stabilizer based on unknown actuator backlash compensation

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Defence Technology（防务技术） 2023年第2期20卷 72-83页

作者： Shu-Sen Yuan Wen-Xiang Deng Jian-Yong Yao guo-lai yang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingChina

Backlash nonlinearity inevitably exists in the actuator of tank horizontal stabilizer and has adverse effect on the system control performance,however,how to effectively eliminate its effect remains a pending *** solve this problem,a robust adaptive precision motion controller is presented in this paper to address uncertainties and unknown actuator backlash of tank horizontal *** controller handles the modeling uncertainties including parameter uncertainties and unmodeled disturbances by integrating adaptive feedforward compensation and continuous nonlinear robust *** on the backstepping method,a smooth backlash inverse model is constructed by combining the adaptive ***,the unknown backlash parameters of the system can be approximated through the parameter adaptation,and the impact of the actuator backlash nonlinearity is effectively compensated via the inverse operation,which can availably improve the tracking ***,the adaptive law can update the disturbance ranges of tank horizontal stabilizer online in real time,which enhances the feasibility in practical engineering ***,the stability analysis based on Lyapunov function shows that with the existence of unmodeled disturbances and unknown actuator backlash,the designed controller guarantees excellent asymptotic output tracking *** comparative results verify the effectiveness of the proposed control strategy.

关键词： Tank Horizontal stabilizer Adaptive control Robust control Backlash inverse

Irreversible demagnetization mechanism of permanent magnets during electromagnetic buffering

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Defence Technology（防务技术） 2021年第3期17卷 763-774页

作者： Zi-xuan Li guo-lai yang Yu-meng Fan Jia-hao Li School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingPR China

The permanent magnets will be irreversibly demagnetized under high temperature and high velocity during the electromagnetic *** this study,the magnetic field induced by eddy currents and the self-demagnetizing field of permanent magnet are taken into consideration together for demagnetization *** magnetic Reynolds number is used to express the eddy currents *** correction coefficient being expressed as the index of the air-gap width,the inner cylinder thickness,iron pole axial length and the permanent magnet demagnetization coefficient is introduced by magnetic path analysis to represent the self-demagnetization effect and the demagnetization *** electromagnetic buffer(EMB)prototype is tested under intensive impact loads of different strengths at room *** accuracy of the nonlinear irreversible demagnetization finite element model is verified by demagnetization on damping force,velocity and ***,high-velocity demagnetization and high-temperature demagnetization are analysed in order to obtain the distribution law of irreversible demagnetization.

关键词： EMB Irreversibly demagnetization Magnetic Reynolds number Correction coefficient

Interval uncertain optimization for damping fluctuation of a segmented electromagnetic buffer under intensive impact load

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Defence Technology（防务技术） 2021年第3期17卷 884-897页

作者： Zi-xuan Li guo-lai yang Feng-jie Xu Li-qun Wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingPR China

Aiming at the problems of demagnetization effect of electromagnetic buffer(EMB)caused by high velocity under intensive impact load and the difficulty and error of machining composite thin-walled long tube,a segmented EMB is *** inner tube and air-gap are divided into initial segments and the traversing *** theoretical analysis,impact test and simulation,it can be found that the RRF curve has two ***,in order to reduce the resultant resistance force(RRF)peaks,the sensitivity analysis based on optimal Latin hypercube design(OLHD)and polynomial regression was *** results show that the smallest contribution ratio to the dynamic response is the seventh and ninth segments of the inner tube,which are less than 1%.Then,fully considering the uncertain factors,important parameters are selected for uncertain optimization after sensitivity *** interval order and interval probability degree methods are used to establish interval uncertain optimization model of the RRF considering *** model was solved using an interval nested optimization method based on radial basis function(RBF)neural ***,the Pareto front is obtained and numerical simulation is performed to verify the optimal *** indicates that the two kinds of RRF peak is obviously reduced,and the optimization object and strategy are effective.

关键词： EMB Intensive impact load Segmented Sensitivity analysis Interval uncertain Optimization

Adaptive robust control for triple avoidance - striking - arrival performance of uncertain tank mechanical systems

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Defence Technology（防务技术） 2022年第8期18卷 1483-1497页

作者： Zong-fan Wang guo-lai yang Xiu-ye Wang Qin-qin Sun Yu-ze Ma The School of Mechanical Engineering Nanjing University of Science and TechnologyJiangsuPeople's Republic of China

This paper puts forward an unprecedented avoidance-striking-arrival problem aiming to address the need for tank's uncertain mechanical systems on the intelligent *** associated system uncertainties(possibly rapid)are time-varying but bounded(possibly unknown).The goal is to design a controller that enables the tank to aim at and attack the enemy tank while keeping itself(out of the enemy fire zone).The tank maintains this condition until reaching the predefined *** this paper,an approximate constraint following control method is adopted to solve this problem,and the original constraints are creatively divided into two categories:the avoidance-tracking constraint and the striking-arrival *** adaptive robust control method is proposed and consequently verified through simulation *** is proved that the system fully obeys the avoidance-tracking-constraint and strictly obeys the striking-arrival constraint under the control ***,the control of the tank vehicle running system and tank gun bidirectional stabilization system are unified to deal with the control signal delay caused by complex uncertainties on the ***,this paper reduced the delay of signal transmission in the system while solved the avoidance-striking-arrival problem.

关键词： Adaptive robust control Multivariable tank system Uncertainty Constraint following Avoidance-striking-arrival

Adaptive robust feedback control of moving target tracking for all-Electrical tank with uncertainty

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Defence Technology（防务技术） 2022年第4期18卷 626-642页

作者： Yu-ze Ma guo-lai yang Qin-qin Sun Xiu-ye Wang Zong-fan Wang The School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

A moving target tracking control problem for marching tank based on adaptive robust feedback control scheme is addressed.A series of preparations is needed for tank gun before shooting a target,the purpose of this paper is to design a control system to fulfill two requirements in this process:the turretbarrel system of tank needs to be adjusted from off-target position to command position and point to the moving target stably when there are strong uncertainties(modeling error,uncertain disturbance with unknown boundaries and road excitation) in the *** the characteristic of coupled interaction,the first thing we do in this paper is to build a coupled analysis model of turret-barrel system with uncertainty term in state-space ***,an adaptive robust feedback control scheme is proposed by adding adaptive law to overcome the ***,multi-body dynamics software is used to establish the mechanical mechanism of the tank,and DC-motor module is established in SIMULINK environment,thus the target information and tracking error of the control system is collected and transferred,the gear-ball screw is derived directly by the output torque of the DC-motor ***,the control system and the 3D model are combined together by means of Recur Dyn/SIMULINK co-simulation,the turret-barrel system of tank can approximately track the moving target in a certain *** the adaptive robust feedback control,the target action is completely followed when the target location is constantly changing.

关键词： Mechanical system Tank stability Uncertainty Road excitation Adaptive robust feedback control

Predicting the electromechanical properties of small caliber projectile impact igniter using PZT dynamic damage constitutive model considering crack propagation

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Defence Technology（防务技术） 2023年第10期28卷 121-135页

作者： Rui-zhi Wang Zhi-qiang Wang En-ling Tang Lei Li guo-lai yang Chun Cheng Li-ping He Ya-fei Han Key Laboratory of Transient Physical Mechanics and Energy Conversion Materials of Liaoning Province Shenyang Ligong UniversityShenyang110159LiaoningChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315211ZhejiangChina

Block piezoelectric ceramics(PZTs)are often used in impact igniters to provide activation energy for electric *** the action of strong impact stress,PZTs release electric energy accompanied by crack initiation,propagation and *** present,the electrical output performance of PZTs in projectile is usually calculated by quasi-static piezoelectric equation without considering the dynamic effect caused by strong impact and the influence of crack propagation on material *** the ignition parameters are always not accurately *** tackle this,a PZT dynamic damage constitutive model considering crack propagation is established based on the dynamic impact test and the crack propagation theory of brittle *** model is then embedded into the ABAQUS subroutine and used to simulate the electromechanical response of the impact igniter during the impact of a small caliber projectile on the ***,the experiments of projectile with impact igniter impact on the target are carried *** comparison between experimental and numerical simulation results show that the established dynamic damage model can effectively predict the dynamic electromechanical response of PZTs in the missile service environment.

关键词： Piezoelectric ceramics Impact Igniter Dynamic damage constitutive model Electromechanical response

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan yang Zhaoyang MA Xingming guo Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma yang Qu Jiaxin Ren Yingying Sun Zhen-Ni guo Yi yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin Dong Dan Zou Zhijun yang Lili guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation