Browse Topic: Management and Organizations

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Study on the Adaptability of Underwater Propeller-Driven Bernoulli Adsorption Device on Irregular Walls2026-99-01727/31/2026
The propeller-driven Bernoulli adsorption device (PBD) has both propulsion and adsorption functions, being suitable for dual-mode underwater robots. Currently, there have been studies on the adsorption performance of PBD on the flat surface. However, the surface morphology of underwater engineering structures is different, and PBD’s adsorption performance on irregular walls still remains unknown. In this letter, based on the potential application scenarios of underwater dual-mode robots, we established four types of irregular wall models to investigate PBD’s adsorption performance on irregular walls. Through CFD simulations and experiments, the adsorption state was analyzed, and the adsorption performance was quantitatively studied.
Liu, Siyue, Hua, Zhong, Yang, Canjun
Research on a Multilayer Membrane Electrothermal Microdriver Based on MEMS Process2026-99-01657/31/2026
Based on the principle of the bimetallic effect of the electrothermal microdrive, polymer SU-eight glue is used as the functional material, nickel metal is used as the structural material, and copper metal is used as the sacrificial layer to make the electric heating microdrive. We process and manufacture them based on specific MEMS processes such as lithography, mask plating, and magnetron sputtering, and perform basic characterization, observation, and electrical signal analysis on the samples. The results show that the overall electrothermal micro-driver device is complete, the electrode and resistance wire structure is complete, and the I-V signal is normal.
Xue, Yunhao, Tan, Xiaolan, Jiang, Xin
The Protective Mechanism of Polyurea/Aramid Fiber Reinforced Steel Pipes against Implosion-Induced Multi-Physical Field Loads2026-99-01357/31/2026
This paper studies the protective performance of polyurea-coated steel pipes and aramid fiber-wound steel pipes under the multi-physical field load of internal explosion by combining experiments with numerical simulation. The experimental results show that applying aramid fiber winding has a limited effect on improving the anti-explosion performance of steel pipes, while polyurea-coated steel pipes exhibit better anti-explosion performance under the coupled load of shock waves and fragments. Simulation analysis reveals the protective mechanism of composite structures in terms of energy absorption and stress distribution, providing a theoretical basis for the optimal design of blast-resistant vessels.
Tian, Xiangpeng, Wang, Tao, Bian, Xiaobing, Huang, Guangyan
Pseudo-Label-Guided Dual-Supervised Alignment for Bearing Fault Diagnosis2026-99-02337/31/2026
The inconsistency in bearing data distributions under diverse conditions often affects the representations of the faulty data and leads to indistinct decision boundaries and even negative transfer resulted from overlapping class distributions, greatly limiting the accuracy of the diagnosis model. To cope with the challenge, a pseudo-label-guided dual-supervised alignment (PDSA) method is developed for bearing fault diagnosis across diverse operating scenarios in this paper. To address the fixed alignment strategy issue, an adaptive distribution alignment layer is incorporated to ResNet18 to achieve dynamic data distribution alignment under varying condition, To enhance classification performances, a dual-supervised mechanism, comprising shallow-layer supervised contrastive learning is introduced through target domain pseudo-labels in target domain and deep-layer regularization class consistency. Experiments on two publicly available bearing datasets demonstrated this model realizes refined class-level alignment, strengthens fault states representation, and shows notable superiority in both accuracy and robustness.
Sun, Hao, Ren, Shijin, Gu, Zhangqing
Advancing Reliability Centered Maintenance: A Robust Statistical Approach for MTBF Estimation in Aero-Engine Fleets via Subgrouping Strategy and Dual Weibull Modeling2026-99-02137/31/2026
Fleet heterogeneity, from manufacturing variations and diverse operating conditions, complicates reliability analysis by obscuring true failure patterns in aero-engines. This is a critical challenge in an industry as inaccurate Mean Time Between Failures (MTBF) estimates threaten safety and inflate operational costs, by forcing a choice between inefficiently conservative maintenance or the risk of in-service failures. Conventional analysis often fails by pooling all fleet data. To address this, our paper presents an analytical framework that improves predictive accuracy by filtering, rather than aggregating statistical noise. The methodology uses a Randomized Block Design (RBD) and ANOVA hypothesis test to screen a diverse dataset and isolate statistically homogeneous subgroups. This filtration identifies a core fleet with a consistent failure signature, providing a purified dataset for modeling. This refined data is then modeled using both Weibull and the Exponentiated Inverse Weibull distributions to ensure the results are robust and not model-dependent. Applying this framework to a 25-engine dataset that experienced 66 failures, we isolated a stable failure pattern, yielding a primary MTBF of 171.16 hours and a cross-validated MTBF of 176.35 hours. The close 3% convergence between these models validates our approach. By providing a dependable MTBF, this work establishes a stronger foundation for data-driven Reliability Centered Maintenance (RCM). It empowers maintenance planners to move toward evidence-based intervals, safely extending engine time-on-wing, optimizing spare parts inventory, and significantly reducing direct operational costs for airlines.
Jubaid, Mayin Uddin, Bebe, Gibson, Bigyen, Musa Pethuel, Anik, S M Kullul Mehedee, Yasmin, Ashrafi, Sahran, Mohamed Sideek Mohamed
Robotic Grinding Trajectory Planning and Correction Method for Large-Scale Complex-Shaped Products2026-99-02277/31/2026
Due to the inherent characteristics of large dimensions, complex curved surfaces, and densely distributed protrusions present in aerospace products, conventional offline programming and trajectory planning techniques for robots primarily prioritize the facilitation of uninterrupted grinding processes and the generation of points along trajectories on surfaces characterized by smoothness. However, these methods encounter challenges in identifying and proactively avoiding surface protrusions during the planning phase. The present paper puts forth a proposal for an automated robot trajectory planning method for grinding operations. This method is predicated on the integration of region partitioning and deformation correction. Specifically, this method first identifies protrusions based on curvature features and rule matching, followed by an analysis of the feasible workspace of a six-axis industrial robot equipped with an external axis. The product surface is discretized into multiple regional units according to the distribution characteristics of protrusions and the constraints of the feasible workspace. Subsequently, a parameter-optimized parallel sectioning method is employed to independently plan trajectories for each unit. The utilization of on-site measured point cloud data facilitates the analysis of contour deviations. In addition, grinding trajectories are dynamically corrected to meet high-precision process requirements. This approach effectively overcomes the challenge that trajectory planning for large-scale, complex-shaped products is easily affected by protrusions. According to the established methodology, the development of an offline programming software system for robotic automatic grinding was initiated. To this end, experiments were conducted on aircraft wall panels to plan and modify grinding trajectories using the proposed method. This process was undertaken to validate the effectiveness and engineering practicability of the proposed method.
Fan, Changhao, Wang, Mingyang, Lv, Ruiqiang, Zhou, Peng
Research and Development of Wheelchair Assisted Intelligent Boarding and Landing Device for Barrier-Free Bus Based on TRIZ Theory2026-99-01477/31/2026
With the intensifying global trend of population aging, enhancing public-transport accessibility for seniors and people with disabilities has become critical. Current wheelchair-assist boarding devices on low-floor buses suffer from cumbersome operation, excessive space occupation, poor adaptation to varying curb heights, and an inability to modulate power output dynamically, all of which compromise travel convenience. This study applies TRIZ theory to solve these problems. Functional analysis, causal-chain analysis, and the nine-screen method were used to identify key issues: excessive space use, insufficient dynamic power adjustment, poor curb-height adaptability, and the lack of self-service capability. TRIZ tools— including the contradiction matrix, substance-field models, and the Ideal Final Result (IFR)—generated conceptual solutions such as a foldable ramp, an adaptive tilting mechanism, an intelligent power-assist system, and an automatic extension device. The resulting integrated unit employs a planetary-gear train combined with a four-bar linkage for compact folding, a servo motor with torque-limiting springs for adaptive height adjustment, torque sensors for real-time power modulation, and a scissor-type telescoping mechanism for automatic stowage. Experimental validation through 50 trials showed that the device completes extension/folding in 7 s, achieves angle adjustment within 3.5 s, covers a pitch range of 0°–43°, and attains a 100 % extension success rate. These features significantly increase automation, adaptability, and user independence, thereby improving the quality of accessible bus services.
Zhu, Zongchuang, Hu, Zhiyong, Liu, Zeshuo, Liu, Yijia, Zhang, Ziqian
Study on Stiffness Model of Bump Foil in Bump Foil Gas Bearings Based on Ansys Simulation Considering Axial Variable Loads2026-99-01747/31/2026
To address the inaccuracy of existing models in describing the stiffness distribution along the axial direction of bump foils, this study first establishes a simulation model applicable to bump foils based on Ansys Workbench. Specifically, by applying axial variable load at a node that matches the distribution of actual operating conditions, the deformation and stiffness characteristics of the bump foil are investigated. The research results show that, compared with the classic Heshmat model, the bump foil stiffness is not uniformly distributed in the axial direction; instead, it exhibits a trend of being higher in the middle and lower at both ends. Notably, when the nominal stiffness values are similar, the axial end displacement obtained from the Ansys simulation differs significantly from the result calculated by the Heshmat model, with the deviation reaching up to 17.7% of the peak displacement from the latter. Furthermore, this study also systematically analyzes the influence of the laws of the bump foil’s curvature radius, length, and friction coefficient on its stiffness.
Wu, Yixuan, Shi, Yiming, Zhu, Jianjun, Liu, Jiajie
Design and Optimization of Hollow Rotating Traveling Wave Ultrasonic Motor Based on Laser Beam Expander2026-99-01547/31/2026
To meet the critical need for rapid response and miniaturization in laser beam expander drive systems, this study proposes an innovative actuation solution based on a hollow rotary traveling-wave ultrasonic motor. By thoroughly analyzing the optical adjustment mechanism of laser beam expanders and the electromechanical coupling behavior of ultrasonic motors, the motor structure was systematically optimized. Using a multiphysics coupling approach, the performance of stators fabricated from three distinct materials was compared, and parametric optimization was conducted. Experimental verification confirms that the developed ultrasonic motor precisely matches the load characteristics of beam-expanding optics while fulfilling the stringent requirements for both fast response and compact design. This research provides a reference for the miniaturization drive of high-precision optical systems, with promising applications in space optics and precision instrumentation.
Qiu, Haihui, Niu, Chuanhu, Xiao, Zhong, Xu, Zhangfan, Li, Jialiang, Pan, Song
Docking Methodology for Large-Sized Irregular Castings via Industrial Robot Manipulation2026-99-01707/31/2026
Large-sized irregular castings are critical components extensively employed in large-scale equipment manufacturing. Due to their substantial dimensions and complex geometries, the assembly and docking processes between different components present significant challenges. To address the docking problem between large-scale irregular castings, this study proposes a casting docking method based on relative pose, along with a modeling approach for irregular castings, and accomplishes the docking process through the control of an industrial robot. Firstly, the current poses of feature points on the docking surfaces are measured. Based on these measurements, the relative pose transformation relationship between the center point of the docking surface and the robot’s Tool Center Point (TCP) is established, thereby constructing the docking model. This model calculates the relative deviation between the current pose and the theoretical pose. Subsequently, the robot motion is controlled according to this deviation to achieve precise docking. Finally, a simulation environment was built using KUKA. Sim Pro with Office Lite to simulate the docking process of large-sized irregular castings. The results demonstrate that the relative pose-based docking method effectively accomplishes the docking task. This study provides an effective solution for the docking of large-sized irregular castings.
Liu, Haoran, Jia, Haili, Wang, Aimin, Xigang, Fan, Peidong, Su
Effects of Arrangement Patterns on Static Stability and Leakage Characteristics in Hybrid Labyrinth-Honeycomb Seals2026-99-01667/31/2026
In this work, three-dimensional models of axial hole labyrinth-honeycomb seals (AHLHS) and circumferential hole labyrinth-honeycomb seals (CHLHS) were established by CFD to investigate the influence of different arrangement patterns on the static stability and leakage characteristics of two seals under choked and unchoked flow conditions and various eccentricities with different values. The results show that the two configurations have different advantageous ranges, and the hole arrangement pattern will not significantly change the pressure difference distribution between the two seals. Under most studied conditions, AHLHS maintains lower absolute values of stiffness coefficients, pressure difference groove, and negative cross-coupled stiffness coefficients, resulting in higher stability.
Li, Qing’an, Gao, Tongxin, Li, Zeze, Pang, Shuai, Lü, Yanjun, Zhang, Yongfang
Research on the Erosion and Wear Characteristics of Gathering and Transportation Pipelines by Cyclone Abrasive Process Parameters2026-99-01847/31/2026
Cyclone abrasive pigging technology, with advantages like environmental friendliness, easy construction, and low destructiveness, has broad application prospects. Studying how the process parameters affect the erosion-wear characteristics of gathering pipelines is crucial for improving pigging efficiency and effectiveness. This study adopted numerical simulations based on gas-solid two-phase flow erosion theory to explore such effects and verified the simulations via a self-designed experimental platform. Results showed that within the given parameter range, erosion rate rose significantly with velocity, especially at 20-30 m/s, peaking at 60 m/s; 0.6 mm abrasives and 0.25 kg/s mass flow rate led to higher erosion rates. Experimental data matched simulations with <10% error, confirming accuracy. Thus, cyclone abrasive process parameters significantly influence pigging performance, and the findings can guide practical operations within the studied range.
Wang, Haoran, Zhou, Xianjun, Li, Long, Song, Huifang, Zhang, Jin, Jv, Xiaolong
Durability Study of Electronic-grade Glass Fibers in Salt-Alkali Environments2026-99-02197/31/2026
Electronic substrates and copper-clad laminates are widely used in modern life, particularly in electronic products such as coastal communication base stations and ship communication and navigation system. In these environments, salt particles carried by sea fog can adhere to the surface of the substrates along with moisture, leading to salt-alkali corrosion of the products. As a core material in electronic components, electronic-grade glass fiber urgently requires investigation into its durability under salt-alkali conditions. Therefore, this study focuses on a specific type of electronic-grade glass fiber and explores its corrosion behavior in three different environments: 2 mol/L NaOH, 1 mol/L cement solution, and 3.5 % NaCl. Soaking durations of 6, 12, 24 hours and 3, 7, and 14days were selected as key parameters. The mechanical properties and surface morphology of the fibers before and after corrosion were observed and analyzed. Experimental results indicate that the glass fiber exhibits higher durability in saline solutions than in alkaline environments. This study provides theoretical support for evaluating the long-term performance of Electronic grade glass fibers in practical applications. It also contributes to the optimization of raw materials and manufacturing processes, enhancing the performance of such fibers in salt-alkali conditions, and offers valuable reference for future research on glass fiber-reinforced composites.
Pu, Qixin, Sun, Siqi, Fang, Qiang, Dong, Shuo, Li, Peng, Wang, Yu, Zhang, Mengxuan, Zhang, Yubo, Yang, Wenfeng, Guo, Peng
Dynamic Analysis and Research on the Influence Exerted by External Sling Load Lifting Point Location on Helicopter Control Stability Characteristics2026-99-02217/31/2026
Regarding the external sling load system of heavy-lift helicopters, the influence of the law of lifting point position on flight control stability characteristics has not been distinctly explained. To address this challenge, this paper constructs a sling load flight simulation model based on multi-body dynamics. Overall, the proposed model consists of four parts, including the rotor aeroelastic coupling model, the fuselage rigid body dynamics model, the flexible sling model, and the slung object rigid body model. Furthermore, through the hub six-degree-of-freedom rigid model and the flexible sling model, this paper realizes the dynamic coupling between the components. On this basis, taking the CH-53E heavy-lift helicopter as the research object, this paper utilizes real flight test data to validate the multi-body dynamic model. Subsequently, this paper systematically analyzes the influence of different lifting points’ lateral position, sling load mode, load-mass ratio, and forward flying speed on helicopter control stability characteristics. Simulation results indicate that the lifting point location exerts a significant impact on the helicopter’s trim attitude angles and dynamic stability. Of them, the lifting point location of the front center of gravity is the optimal in terms of trim characteristics and eigenvalue distribution. Furthermore, within a certain flight speed range, the lifting point of the front center of gravity demonstrates superior speed adaptability and system robustness. Apart from providing a solid theoretical basis for the lifting point layout design of the external sling load system of heavy-lift helicopters, the research results have important engineering application value for improving the safety of sling load flight of heavy-lift helicopters.
Wang, Zixin, Zhang, Honglin, Meng, Xiaowei, Zhang, Yunrui
Simulation Research on Non-Destructive Testing of Pipeline Based on Ultrasonic Guided Wave2026-99-01437/31/2026
Ultrasonic guided waves enable long-range, low-intrusion inspection of pipelines. This study examines how array topology and axial spacing influence the quality of defect echoes when the longitudinal axisymmetric mode L(0,2) is used. We build COMSOL finite-element models of a steel pipe and excite it with PZT-4 at 80 kHz; three practical layouts are compared: (i) odd–even receiving, (ii) 8-transmit/8-receive, and (iii) 16-transmit/8-receive, arranged as two axially separated groups. The spacing between the groups is chosen to suppress parasitic modes such as L(0,1) and to strengthen L(0,2). Results show that the two-group configuration sharpens the defect echo and reduces modal interference; increasing the number of transmitters further raises the defect-wave amplitude and improves the separation from end-reflection echoes. Among the schemes, 8×8 performs well for small-defect identification, while 16×8 yields the clearest boundaries and fastest defect indication. These findings clarify how sensor number and placement govern modal purity and sensitivity, and they offer practical guidance for designing guided-wave arrays that improve the reliability of long-range pipeline inspection. - Ultrasonic guided waves Pipeline non-destructive testing L(0,2) mode; Sensor array layout; Finite element simulation; Guided wave signal processing.
Liao, Wei, Li, Tengfei, Zhang, Wenhui, Lin, Qingming, Guo, Yanbing
Experimental Study on Suppression of Lithium-Ion Battery Fires Using Clean and Efficient Aqueous Fire Extinguishing Agents2026-99-01337/31/2026
This study investigates the suppression of lithium-ion battery (LIB) fires using composite aqueous extinguishing agents, with a 20 Ah lithium iron phosphate battery as the experimental subject. Based on the functional selection of coverage-isolation and cooling-smothering, three aqueous extinguishing agents, S-E-1, S-E-2, and S-E-3, were designed and developed using hydrocarbon surfactants. The results indicate that all three aqueous fire extinguishing agents can effectively suppress LIB fires. Through a comprehensive evaluation of extinguishing time, cooling rate during extinguishing agent release, and physical and chemical parameters of the extinguishing agents, the optimal formulation was determined to be 2% SDS (sodium dodecyl sulfate), 1% SDBS (sodium dodecyl benzene sulfonate), 3.5% CAB (cocamidopropyl betaine), 1% APG0810 (alkyl polyglycoside), 1% CDEA (coconut oil acid diethanolamine), 0.32% CH4N2O (urea), 1.5% NH4H2PO4 (ammonium dihydrogen phosphate), 0.5% C2H6O2 (glycol), 1.5% Na3PO4 (sodium phosphate), and deionised water, demonstrated the best performance. Reducing the extinguishing time to 14 seconds, a 41.7% reduction compared to pure water, and increasing the cooling rate to 0.816 °C·s^–1, which is 4.4 times that of pure water, with no reignition observed. This work contributes to the theoretical principles needed to engineer next-generation fire suppression materials for lithium-ion batteries that are both efficient and eco-friendly.
Yu, Tao, Zhu, Shunbing, Li, Ke, Zhang, Menglan
Research and Application of Mechanical Voltage Stabilization Control Device2026-99-01197/31/2026
This study carefully designed and successfully developed a mechanical voltage stabilizing control device. The device uses silicone oil as the key component material of the liquid spring and 1Cr13 as the main material of the pressure control unit, enhancing its high-pressure resistance (up to 35 MPa), oxidation resistance, and acid-alkali corrosion resistance. By optimizing the transmission mechanism and simplifying the pressure regulation module, the device achieves a pressure regulation range of 0.1–21 MPa with an accuracy of ±0.01 MPa, significantly broader and more precise than traditional devices. To address manufacturing challenges, advanced CNC machine tools, ceramic cutting tools, and optimized heat treatment processes (e.g., quenching and tempering) were adopted, ensuring component machining accuracy within ±0.02 mm. Field applications in 13 oil wells demonstrated a 15.6% increase in daily oil production (from 25.5 t/d to 29.5 t/d) and a 17.9% increase in daily gas production (from 2800 m^3/d to 3300 m^3/d), with stable casing pressure control at 5.3 MPa. The device has created 1.225 million yuan in economic benefits while eliminating safety hazards, providing critical technical support for efficient and environmentally friendly oil and gas production.
Wang, Gang, Liu, Cuicui, Tong, Deshui, Cao, Jian, Mu, Taiji, Han, Baidong
Preparation and Characterization of Glycerol-Based Fe3O4 Magnetic Fluids2026-99-02447/31/2026
To optimize the preparation protocol and tribological performance of glycerol-based Fe^3O^4 magnetic fluids, three hybrid agitation systems—(i) chemical co-precipitation coupled with magnetic stirring (H+C), (ii) chemical co-precipitation coupled with mechanical stirring (H+J), and (iii) chemical co-precipitation integrated with mechanical plus ultrasonic agitation (H+J+C)—were systematically investigated with respect to their influence on the physicochemical characteristics and lubricating behaviour of the resulting magnetic nanoparticles. Relative to the H+C and H+J protocols, the H+J+C protocol effectively suppressed intermediate agglomeration, yielding a 15 % increase in Fe^3O^4 productivity and a 15 % reduction in the full-width at half-maximum of the particle-size distribution. A binary surfactant system composed of oleic acid and citric acid achieved complete surface passivation, producing nanoparticles with a saturation magnetization of 59.2 emu g^–1. Under a magnetic flux density of 0.0341 T, tribometric evaluation revealed that the friction coefficient of the fluid prepared via the H+J+C route decreased to 0.041, corresponding to reductions of 7.1 % and 22 % relative to the H+J and H+C counterparts, respectively, thereby demonstrating superior tribological performance. The present work furnishes an experimental foundation for the rational design of high-performance magnetically responsive lubricants and the optimization of magnetic-fluid synthesis protocols.
Hu, Rui, Zhong, Shihao, Xu, Chunxia, Chen, Binhua, Liu, Yang
Modelling Failure Propagation in Material-Driven Collaborative Manufacturing Networks Using Cellular Automata2026-99-01207/31/2026
Collaborative manufacturing networks enhance production efficiency but are increasingly vulnerable to cascading failures due to their complex interdependencies, particularly in critical processes like gear manufacturing. This study addresses this challenge by proposing a dynamic modelling framework based on Cellular Automata. Utilizing manufacturing resource and task scheduling data, a material flow-driven Directed Acyclic Graph (DAG) is constructed to capture the network’s hierarchical topology. Key innovations include state transition rules with memory effects, where dynamic failure probability integrates neighbouring node states and historical failure records, governing normal node failure, recovery, and re-failure (with an attenuation factor reflecting enhanced resilience). The case study focusing on the gear manufacturing industry, through simulations on a 100-node gear production network, reveals spatiotemporal failure propagation patterns. By implementing resource redundancy configuration and material flow optimization, iterations generally converge around 35 steps, demonstrating significant self-recovery potential and strong network robustness in collaborative manufacturing networks. This approach provides a scientifically grounded tool for identifying cascading risks in collaborative manufacturing networks.
Bai, Hao, Kou, Zhida, Liang, Jingya, Zhang, Cheng
Optimization of Pneumatic Conveying Elbows to Reduce Grain Particle Normal Contact Forces via CFD-DEM Coupling Method2026-99-01167/31/2026
This study presents a refined design for pneumatic conveying pipelines, featuring a grooved structure at the bend aimed at reducing particle breakage during transportation. Using soybean particles as a focus, the research employs a gas-solid two-phase flow approach to explore how different groove depths and widths influence the breakage rate. We used CFD-DEM simulation techniques, combining fluid mechanics with discrete element modeling to achieve a more accurate representation of particle motion and collision forces during expressing. Based on these simulations, we identified the most effective combination of groove width and spacing. Experimental results showed that a groove width of 4.5 mm coupled with a 40 mm spacing could decrease impact forces on particles by approximately 5% to 10% at expressing speeds of 15 m/s and 20 m/s. Throughout all measured time intervals, the impact forces remained stable, with turbulence exerting minimal influence on the particle forces.
Luo, Xinhao, Yang, Tiancheng, Huang, Bo, Mao, Genwu, Dong, Deliang, Shi, Heng, Li, Xiaoliang, He, Bo
Construction of a Digital Management Platform for Intelligent Workshops in the Electronics Industry2026-99-01177/31/2026
Under China’s intelligent manufacturing strategy, manufacturing enterprises are expected to achieve digital and networked operations by 2025, with full digital transformation by 2030. Intelligent factories, the core of this transformation, rely on interconnected, integrated, and data-fused systems. This paper focuses on the micro-assembly intelligent workshop at the Nanjing Research Institute of Electronics Technology, which produces micro-circuit modules for large-scale complex electronic systems. The workshop combines discrete and process manufacturing modes, presenting unique challenges for digital management. A digital management platform based on a five-layer architecture (device, network, data, application, and decision layers) is proposed to address multi-dimensional business needs, including production scheduling, logistics, execution, and decision optimization. A hierarchical workflow structure of the workshop, consisting of a main workflow and several sub-processes, is in-depth studied and designed. The platform is constructed based on requirements analysis and workflow design of the workshop and integrates systems such as MES, APS, WMS, and SCADA, supported by AI-driven big data analytics. This study offers a practical framework for advancing digital transformation in the electronics industry.
Zhang, Jian, Wang, Jiafeng, Guo, Yongzhao
Study on the Contact Stress Distribution and Calculation Method of Cylindrical Roller Bearings Considering Clearance Changes2026-99-01247/31/2026
The distribution of contact stress in roller bearings has a significant impact on operational performance and safety. Firstly, we established a bearing clearance change model that combines interference fit and thermal expansion effects. Then, we studied the clearance changes of key parameters’ influence under different operating conditions. Using Hertz contact theory, we analyze the nonlinear coupling relationship between clearance changes, load distribution, and contact stress. Through MATLAB analytical calculations, load and stress distribution contour maps were obtained under typical operating conditions, which provided theoretical support for bearing optimization design and reliability analysis. The result depicts that an increase in interference fit and temperature difference leads to clearance decrease, triggering a redistribution of contact stress. As clearance decreases, the maximum contact stress exhibits a nonlinear growth trend. To further enhance engineering practicality, this paper uses the MATLAB platform to develop a visualization of digital image processing software. The software enables interactive analysis throughout the entire process of clearance input, stress calculation, and graphical display.
Pang, Yiqing, Cai, Hongbin, Ren, Siyang
Study on Energy-related Mechanisms of Aeroelastic Instability of Ultra-Long Flexible Wind Turbine Blades Under Various Working Conditions2026-99-01347/31/2026
With the continuous increase in wind turbine power capacity, ultra-long flexible blades face intensified aeroelastic instability risks due to reduced structural stiffness, enhanced modal coupling, and aerodynamic nonlinearity. In addition to the analysis of basic vibration characteristics, this study focuses on energy-related mechanisms of aeroelastic instability under various working conditions. Using a numerical model integrating Dynamic Blade Element Momentum Theory (DBEMT) and Geometrically Exact Beam Theory (GEBT), over 400 time-domain simulations were conducted to characterize instability onset and development. Results reveal four distinct aeroelastic instability regions, each dominated by specific modes. In Region A, flutter dominated by the 2nd flapwise mode is observed. In Region B, flutter dominated by the 1st edgewise mode is observed. In Region C, flutter dominated by the 2nd edgewise mode is observed. While in Region D, where the medial angle of attack (AoA) of the blade has exceeded the stall angle, stall-induced vibration dominated by the 1st flapwise mode is observed. Energy analysis shows aerodynamic work concentration near the blade tip drives instability, with diverse energy exchange patterns across regions. Except for some operating conditions in region C, where instability is dominated by edgewise energy absorption, most aeroelastic instability conditions are dominated by flapwise energy absorption. Torsional degree of freedom contributes minimally to aerodynamic work, but the torsional vibration exerts a notable influence on the AoA. This, in turn, changes the comprehensive aerodynamic forces impacting the blade as well as the general aeroelastic stability. This study clarifies the relationship between operating conditions and energy-driven instability, offering some reference values for the design work and safety assurance of ultra-long flexible blades of the wind turbine.
Wang, Su, Chen, Jiajia, Zhou, Le, Shen, Xin, Li, Chun, Du, Zhaohui
Design and Application of Simulation-Based Lifting Tool for Fabric Truck Roller Replacement2026-99-01377/31/2026
In the process of replacing the rollers of the fabric cart of the tobacco storage cabinet, in order to solve the problems of low replacement efficiency and high safety risk.This article proposes a specialized lifting tool for fabric cart rollers with a self-locking and adopts the screw lifting structure, which facilitates roller maintenance operations, and conducts SolidWorks Simulation calculations and dynamic simulation methods. Jinan Cigarette Factory fine cigarettes special line leaf silk temporary storage cabinet fabric car roller replacement, for example, the results show that: the average operating personnel reduced by 50%, the replacement time from 6.7h to 1.2h, efficiency increased by 458%, This innovation significantly reduces the labor intensity of maintenance personnel and ensures a safe and reliable replacement process.
Zhang, Lei, Xue, Yifei, Zhang, Ge, Sun, Yanzhao, Wang, Hongbin, Cheng, Linfeng
Seismic Performance and Reinforcement Strategies for ±600 kV Suspended Converter Valves — Part1: Seismic Vulnerabilities2026-99-01457/31/2026
The suspended converter valve constitutes the fundamental equipment essential for the functioning of direct current power transmission infrastructure. The electrical equipment has been severely damaged in historical seismic events, underscoring the earthquake resistance of thyristor valve is critical for maintaining secure and consistent performance of energy delivery systems. Current seismic research focuses on ±800 kV converter valves, while studies on ±600 kV converter valves are lacking. Due to significant differences in the length of suspended insulators between ±600 kV and ±800 kV converter valves, their seismic responses differ considerably. A three-dimensional finite element model encompassing both the ±600 kV suspended converter valve and its supporting valve hall structure was developed to accurately capture their dynamic interactions under seismic excitation. The modal analysis is conducted, and the natural frequencies and mode shapes of converter valve and valve hall system are obtained. The seismic analysis results indicate that under 1 g seismic excitation, the calculated maximum seismic displacement of the suspended valve tower is 421 mm, exceeding the engineering design limit of 400 mm. The calculated minimum stress safety factor for the converter valve suspended insulators is 1.46, failing to meet the specified requirement of no less than 2. Both the swing amplitude of the converter valve and the stress on the suspended insulators exceed design limits. It not only poses a mechanical safety risk to the converter valve, but the excessive seismic displacement can also lead to seismic coupling effects between the converter valve and critical equipment. Therefore, further research on damping measures is required for the seismic vulnerabilities of ±600 kV suspended converter valves.
Lin, Sen, Zhu, Zhubing, Lu, Zhicheng, Sun, Yuhan
Microstructure and Mechanical Properties of Vacuum Laser Welded Joints in 42CrMo Thick Plate2026-99-01327/31/2026
Vacuum laser welding trials were carried out on 42CrMo steel, a material widely utilized in the defense sector. By employing a 30 kW fiber laser system, complete penetration welds were successfully produced on 20 mm thick 42CrMo steel plates. The resulting joints displayed satisfactory surface quality on both the top and bottom sides, with no evident defects such as cracks or porosity. A comprehensive analysis of the joint microstructure and mechanical properties was conducted. Findings reveal that the weld zone (WZ) is predominantly composed of lath martensite, accompanied by minor quantities of plate martensite, organized as columnar crystals. The joints demonstrated high tensile strength at ambient temperature, with fracture consistently occurring within the base metal (BM). Microhardness measurements indicated higher values within the weld relative to the base metal, and no pronounced softening was detected in the heat-affected zone (HAZ). Additionally, the joints exhibited commendable impact toughness, suggesting overall superior mechanical performance.
Shi, Haicheng, Zhang, Guoyu, Li, Wuhong, Cao, Dongxu, Liu, Tianlei
An Automatic Cleaning System for Copper Bar Chain of Cigarette Cutting Machine2026-99-01317/31/2026
The cutting machine is a critical component in the cigarette processing line, and its cutting quality depends on the operational condition of the copper bar chain. The grooves on the surface of the copper bar chain accumulate dust during the operation of the machine, which often causes unstable conveyance of raw materials, significant width variations, and a high defect rate. To address this issue, this study developed a linear reciprocating automatic cleaning system for copper bar chains to remove dust from the groove surface and hinge joints. Experiments have verified that the system improved the cutting qualification rate, increased the operational stability of the cutting machine, reduced manual cleaning workloads, and reached higher cleaning efficiency. This innovative system is also expected to provide a valuable reference for similar equipment manufacturers and advance technological innovation in the cigarette processing industry.
Li, Haitao, Zhang, Chunyuan, Fang, Junqing, Su, Lin, Chen, Peng, Guo, Zhiwei, Xing, Dongdong
Design and Development of a Durability Test Device for the Surface of Elderly-Friendly Mattresses2026-99-01397/31/2026
A test device for detecting the durability of the surface of elderly-friendly mattresses was designed and developed, which has functions such as force value monitoring, displacement monitoring, data recording, and hardness grade determination. Through the collaborative work of the mechanical system and the control system, high-precision reciprocating rolling tests and hardness grade determination on the mattress surface are realized. The verification test results show that the relative standard deviation (RSD) value of the mattress hardness grade test results is less than 10%, indicating that the detection data obtained by using this device is stable, meets the design requirements, and has operability.
Wang, Jin, Feng, Panpan, Shen, Guofeng, Zhang, Lei
Design of a Fully Automated Tea Packaging System Based on an Improved Genetic Algorithm2026-99-01137/31/2026
Manual operations in traditional tea packaging lines often suffer from low productivity, safety risks, and inconsistent labeling quality. To overcome these limitations, this study develops a fully automated tea packaging system guided by an improved genetic algorithm. The system integrates five functional modules—bag feeding, bag opening, material filling, sealing, and labeling—into a seamless workflow. By applying the optimization capability of the improved genetic algorithm, the system achieves better coordination among modules, higher adaptability to different bag shapes and sizes, and improved operational efficiency. Experimental validation demonstrates that the proposed design not only simplifies the packaging procedure but also enhances precision, reliability, and production speed. The system provides a flexible and intelligent solution applicable to a wide range of tea packaging requirements.
Guo, Hui, Zhao, Zhikai, Yuan, Weilong, Lin, Lin, Yu, Yunchang, Gao, Jiashun
Parameter Identification for the Dynamics Model of a Robotic Grasping Process Based on SFOA2026-99-01237/31/2026
To precisely simulate the nonlinear dynamic characteristics of a robotic arm grasping cylindrical objects from storage units, this study establishes a dynamic model of the robotic grasping process incorporating Coulomb and viscous friction models to characterize frictional properties. Furthermore, to effectively identify unknown parameters in the dynamic model, a parameter identification method based on the Superb Fairy-wren Optimization Algorithm (SFOA) is proposed. The root-mean-square error (RMSE) between the displacement responses from the dynamic model and the experimentally acquired displacement data serves as the optimization objective. Multiple sets of experimental data are utilized to identify the unknown parameters of the dynamic model. The results demonstrate that when the identified parameters are applied to the dynamic model, the goodness-of-fit between the model’s response displacement data and the experimental displacement data exceeds 0.999. This validates the effectiveness and accuracy of the proposed method for identifying unknown parameters in dynamic models.
Shen, Shaofeng, Yang, Liu, Wang, Zihan, Han, Qunyi
A Simple Method for Synthesizing Wear-Resistant Superhydrophobic Anti-Icing Coating2026-99-01297/31/2026
This research demonstrates a facile method for fabricating an anti-icing coating through spray deposition on a metallic substrate. A dual-layer structure was designed to enhance icephobic properties: a primer layer incorporating fluorocarbon resin, butyl acetate, and rod-shaped micrometer-sized metal oxides to establish a secondary roughness morphology, followed by a topcoat composed of butyl acetate and nano-scaled superhydrophobic particles. Evaluation of the coating performance revealed a maximum water contact angle of 171.9°, indicating exceptional hydrophobicity. Furthermore, the coating exhibited notable abrasion resistance and anti-icing capabilities against overlaying ice.
Li, Dongyang, Xu, Zelong, Wu, Jiang, Tong, Wei, Wang, Weiqing, Cong, Rimei, Qian, Jiawei, Qu, Shaohui
Measurement and Regulation of Residual Stress in Door Opening Welds of Wind Turbine Towers2026-99-01977/31/2026
Weld residual stress is a critical factor affecting the structural integrity and service life of wind turbine towers. In this study, a systematic investigation was conducted on the residual stress distribution and control methods for door corner welds of an in-service wind turbine tower after approximately 20,000 hours of operation. X-ray diffraction (XRD) measurements revealed significant tensile residual stress in the weld and heat-affected zone, with peak values reaching 315 MPa, particularly concentrated at depths of 5-7 mm. To mitigate these stresses, two post-weld treatment methods were employed: ultrasonic impact treatment (UIT) and localized heat treatment. UIT effectively transformed surface tensile stress into compressive stress, achieving a maximum compressive residual stress of -372 MPa within a depth of 3 mm, while simultaneously refining grains and increasing surface hardness. In contrast, localized heat treatment at 460 °C for 5 hours led to a broader stress relief effect, reducing residual stress by approximately 100 MPa without causing significant changes to the macrostructure, but inducing substructural rearrangements beneficial for stress relaxation. Mechanical testing confirmed that both treatments improved tensile strength, ductility, and toughness of the welds. The combined findings demonstrate that ultrasonic impact treatment is highly effective for enhancing fatigue performance at the surface, while localized heat treatment offers advantages for deep stress redistribution and long-term structural stability. This comprehensive approach provides valuable technical guidance for residual stress management in complex welded structures of wind turbine towers.
Sun, Wanting, Zhong, Zhenqian, Zhang, Bo, Liu, Hui
Ultrasonic Assisted Room Temperature Welding of Liquid Gallium Indium Alloy Brazing Material and Its Solidification Behavior at the Cu-Cu Interface2026-99-01967/31/2026
Considerable the gallium-based alloys low melting point coupled with easy to synthesize intermetallic compounds with diverse metallic elements, employing liquid gallium-based alloys as the soldering medium and leveraging ultrasonic as assistance are effective to construct pure copper joints under atmosphere condition. The investigation delves into the characterization of the reaction products, interface microstructure, elemental distribution patterns, and evolution of shear strength within the welds. Furthermore, the pivotal role of ultrasonic waves and constituent element diffusion mechanisms during the solidification phase is elucidated. Thus, the initial one-day occurred during solidification showed the 2.6 MPa shear strength but with the time increased to four and a half days, the shear strength raised to 8.4 MPa at room temperature. Thereinto, the results indicate the weld seam has achieved metallurgical connection. This innovative welding technique operates at room temperature provides significant guidance for designing a novel perspective low-temperature joining for applications. It is not only augments the repertoire of material connection methodologies but also presents a viable joining strategy for sensitive elevated temperature materials. Therefore, such process possesses substantial practical significance and promises avenues for future applications.
Guo, Manying, Qu, Yingying, Fang, Qiuyue, Yang, Shen
Force-Balance Analysis of Surface Instability in a Tri-Layer Film/Substrate Structure2026-99-02157/31/2026
Driven by increasing engineering demands, the need for high-performance flexible electronics has surged, accelerating the development of stretchable devices within mechanics. Among multilayer structures, the film/substrate architecture serves as a typical example, and its buckling behavior remains a longstanding focus of mechanical investigation. This work examines how an elastic film bonded to a soft tri-layer substrate loses stability, producing wrinkled surface patterns under compression. We first construct a mechanical model, then derive an analytical expression for the wrinkle amplitude using a force-balance approach, and finally employ finite-element simulations and theoretical comparisons, we systematically explore how the middle layer’s stiffness and thickness jointly govern the onset, wavelength and amplitude of surface buckling, revealing quantitative selection rules that have not previously been reported for tri-layer structures. The results show that the tri-layer film/substrate structure exhibits two instability modes: film-intermediate co-buckling and film-only wrinkling. By simply varying the middle layer’s elastic modulus or its thickness, one can move the structure across the boundary that separates the film-only and bi-layer buckling regimes, providing a direct mechanical selection for on-demand mode. In addition, the wrinkle amplitude increases monotonically with the applied initial strain. Those findings offer a theoretical reference for designing flexible electronics based on film/substrate structures.
Chen, Hao, Zhang, Wulin, Song, Yahui
Design and Research of Robotic Arm for Belt Conveyor Roller Replacement2026-99-01877/31/2026
To address the high failure rate of rollers in coal mine belt conveyors, the inefficiency of manual replacement, and the operational disruptions caused by maintenance shutdowns, this study proposes a robotic arm system capable of replacing rollers without halting conveyor operations. The research focuses on the kinematic performance and path planning strategy of the robotic arm. A kinematic model is established using the Denavit–Hartenberg (DH) parameters, and the workspace distribution is analyzed via the Monte Carlo method. The results show that the horizontal reach exceeds 2020 mm and the vertical reach extends up to 2000 mm, which fully satisfies the spatial requirements for roller replacement across the entire conveyor system. In the path planning phase, an obstacle expansion model is constructed, and an improved Informed RRT* algorithm is implemented to generate collision-free trajectories, ensuring effective obstacle avoidance. To improve trajectory smoothness, path pruning and cubic B-spline interpolation are applied to refine the initial paths. For trajectory planning in joint space, quintic polynomial interpolation is employed, with boundary conditions set to ensure zero velocity and zero acceleration at both the start and end points, thereby guaranteeing smooth and stable motion of the robotic arm. Simulation results indicate that joint angles, angular velocities, and angular accelerations vary smoothly throughout the roller grasping process, without abrupt changes, and converge to zero at the beginning and end of the trajectory. End-effector trajectory tracking error analysis reveals positioning errors within 0.8 mm for side rollers and 3 mm for central rollers, well within acceptable engineering accuracy thresholds. This work provides a theoretical foundation and a practical implementation framework for advancing automation and intelligent operation in roller replacement tasks within coal mine belt conveyor systems.
Pu, Congyuan, Qian, Ke
Research and Application of Low-Cost Aerospace Chip Burn-in Systems2026-99-01587/31/2026
In view of the key problems—low chip burn-in efficiency and high burn-in costs—caused by high R&D costs and a limited number of veneer stations in the traditional burn-in system used in the military aerospace field, this project has carried out a series of innovative research. Through systematic scheme optimization design and strict cost control measures, a new burn-in system with significant cost advantages and supporting multi-station parallel processing has been successfully developed for the aerospace field. The core technical breakthroughs of the system are mainly reflected in three aspects: first, through architectural reconstruction, the number of single incubator stations has been increased by leaps and bounds from the traditional 60 to 720; secondly, the use of intelligent monitoring technology can expand the scale of the workstation while using the display for process monitoring and data collection; Finally, the modular design concept is innovatively introduced, which greatly reduces the construction cost per workstation. Actual tests have verified that the processing efficiency of the AD1120 chip burn-in system has achieved a significant improvement of 1100%, which is equivalent to increasing the processing capacity of a single batch by 11 times. Up to now, the system has completed the 160-hour continuous burn-in test of 5,000 AD1120 chips, during which the system operation is stable and reliable, and there is no abnormality in the use of the test chip manufacturers. This breakthrough performance improvement not only significantly shortens the product development cycle but, more importantly, provides a practical technical solution for batch screening of high-reliability chips. Subsequent promotion and application can meet the mass production needs of a variety of chips in the aerospace industry, and provide a way to reduce costs and increase efficiency for the same type of unit.
Gu, Zucheng, Kang, Xiao, Jiang, Shang
Research on Reliability Test Methods for Electric Drive Axle Differentials2026-01-50447/31/2026
With the rapid development of the global economy, issues such as the energy crisis and environmental pollution have become increasingly severe. Owing to their environmental friendliness, structural simplicity, and high energy efficiency, electric vehicles have attracted widespread attention. Electric drive technology serves as the most promising and versatile propulsion solution for battery electric vehicles, hybrid electric vehicles, and fuel cell vehicles. As an advanced mechatronic transmission system, the electric drive axle offers high transmission efficiency, flexible packaging, and ease of digital and active chassis control integration, and has thus been increasingly adopted in modern vehicle architectures. The differential is a key component within the electric drive axle, responsible for regulating the rotational speed difference between the left and right wheels and ensuring balanced torque distribution. It plays a decisive role in vehicle stability and traction performance. This study focuses on the reliability testing methodology for differentials in electric drive axles, primarily including the extraction of reliability test conditions and the feasibility analysis of the proposed testing scheme. Specifically, based on the parameters of a given electric vehicle, a Simulink model of the motor and differential is established, and a complete four-wheel-drive vehicle model is constructed. Through simulation under typical driving conditions, operational data of the rear-drive axle differential are obtained. The collected data are then preprocessed and subjected to dimensionality reduction using Principal Component Analysis. The selected principal components are further analyzed using K-means clustering to construct representative differential reliability test conditions. The limitations of existing testing methods are analyzed based on the simulated results and relevant literature. Finally, a reinforced fatigue testing method for the differential is designed according to the extracted test conditions, and the feasibility of the corresponding test bench is evaluated.
Zheng, Hongyu, Li, Ziyu, Wang, Dajiang, Tian, Kai
Reliability Evaluation of CNC Machine Tools from a Design Team Perspective2026-99-01947/31/2026
Reliability evaluation aims to quantify the reliability level of equipment and to verify its compliance with reliability requirements. Existing reliability evaluation methods primarily rely on operational phase data, which means reliability evaluation may lag behind actual needs. In practice, both users and design teams are more concerned with how to estimate CNC machine tools’ reliability before they are put into operation. Moreover, current reliability evaluation methods usually ignore the design team’s influence on CNC machine tool reliability. To overcome these limitations, this study proposes a novel reliability evaluation method that accounts for the influence of the design team on the reliability of CNC machine tools. By analyzing the impact of the design team’s technical capabilities and reliability capabilities on CNC machine tool reliability, a set of quantifiable evaluation indicators was established. Then, the weight coefficients of all indicators were determined using the expert scoring method. Finally, all data were integrated using the vector projection method, which enabled a quantitative reliability evaluation of CNC machine tools from different design teams within the same category. Additionally, the proposed method was applied to conduct practical case studies on multiple CNC external cylindrical grinding machine tools designed by different design teams, thereby validating the feasibility of the proposed method. The reliability evaluation results not only determine the reliability level of each CNC machine tool but also identify the weak points in the technical capabilities and reliability competencies of each design team. This study concludes by discussing the significance of this approach for enhancing the reliability capabilities of design teams and its practical implications for end users.
Sun, Dongyang, Zheng, Weixu, Chu, Hongyan, Xu, Jingjing, Cheng, Qiang
Research on the Influence of Creping Process and Microstructure on the Properties of Crepe Paper Products2026-99-02067/31/2026
Crepe paper has extensive applications in the electrical field and significantly influences the operation of power equipment. The creping process and microstructure play a crucial role in determining its performance. However, optimizing them to improve the performance of crepe paper remains a challenge. Therefore, in this study, univariate and multi - factor interaction experiments were set up to explore the impact of the creping process on crepe paper. X - ray diffraction (XRD) and Fourier - transform infrared spectroscopy (FTIR) techniques were used to analyze the microstructure of crepe paper. The results show that smaller scraper angles and moderate pressures can increase the paper density, and the use of different creping aids can improve the paper’s performance. Higher crystallinity enables crepe paper to have better mechanical and thermal stability. Moreover, based on the experimental results, a scheme for optimizing process parameters was proposed to help improve the quality of domestic crepe paper and provide support for the development of domestic electrical crepe paper production technology.
Meng, Gao, Ran, Zhuo, Yuan, La, Zengchao, Wang, Bin, Zhang
Research on the Axial Assembly Stress and Fatigue Life of 60-Series Harmonic Reducers2026-99-01917/31/2026
This study presents a systematic investigation into the assembly stress and fatigue life of 60-series harmonic reducers. A sophisticated finite element simulation model is constructed to precisely simulate the real assembly process and calculate stress distribution in the flexspline under axial assembly errors. In addition, corresponding fatigue life tests are designed to explore the influence of different axial assembly errors on the number of rotation cycles and transmission efficiency of the harmonic reducer. By comparing the predictions of the fatigue life mathematical model with the test data, a reliable fatigue life prediction method is established, providing a solid theoretical basis for the whole-machine assembly process and reliability design of this series of harmonic reducers.
Du, Yuefei, Qiu, Haodong, Fan, Yong, Li, Ziyuan, Dong, Yi, Zhang, Chi, Li, Chenzheng, Li, Yuan
Implementation Strategies of Requirements Engineering in Commercial Aircraft Airframe Forward Design2026-99-01837/31/2026
Focusing on the requirements engineering activities, this study analyzed the problems in the implementation process of the forward design practice of commercial aircraft airframe, introduced the breakthrough methods, including the convergence and integration with the traditional design process, the supporting work organization model, process optimization, and specification, and proposed the airframe stakeholder need capture model based on the theory of systems engineering. Practice has shown that the requirements engineering implementation strategy introduced in this paper can effectively resolve conflicts and redundancies between the requirements system and the original top-level document system requirements. It ensures clear requirements sources, sufficient basis, reasonable allocation, controllable changes, adequate change assessments, clear design status, and controllable design risks. It effectively overcomes human resource bottlenecks during the early stage of requirements engineering implementation while cultivating talent reserves for systems engineering implementation, saving approximately 23.5 person-years in labor costs. It significantly optimizes non-value-added processes, reducing approximately 100 reports. It unifies the team’s understanding of requirements work, improves coordination efficiency, and significantly improves the requirements validation rate between aircraft-level and system-level requirements by an average of approximately 46%. It assists stakeholders and engineers in systematically and scientifically capturing product requirements during the design phase, with original product design specifications covering approximately 70% of subsystem specifications on average. Given its generality across the airframe forward design domain, the airframe requirement management paradigm established by this implementation strategy holds significant importance for the comprehensive and in-depth application of systems engineering methods in commercial aircraft development.
Sun, Luyan, Chang, Liang
A New Ternary Phase Diagram Prediction Descriptor Combined with Machine Learning Research2026-99-01807/31/2026
The morphological characteristics of ternary phase diagrams play a pivotal role in optimizing material properties and facilitating the design of novel alloys. In this study, machine learning (ML) is used to predict the number of phases in ternary alloy systems. A new feature descriptor for phase diagram prediction is proposed in ML, which includes the characteristics of element properties, thermodynamic properties of materials and CALPHAD parameters. Initially, this study constructed a dataset comprising various feature descriptors and validated their correctness employing ML models such as LRC, SVM, RFC, Bagging and GBDT. Subsequently, comparing the performance of different models, and the better-performing models Bagging and GBDT were selected for further prediction studies. The models were fine-tuned using grid search and random search methods to optimize their predictive performance. Ultimately, by predicting phase diagram data for multiple ternary systems at different temperatures, the accuracy rate near the temperature range of the given experimental data was approximately 82%. This demonstrates phase diagram descriptors in conjunction with machine learning to predict ternary phase diagram proposed in this study is practicable. The predicted data also provide guidance for experimental determination of phase diagrams and lay the foundation for future material design and optimization.
Fan, Hanchao, Su, Yu, Jin, Zongxiao, Li, Jun, Lee, Soowohn, Tang, Jianguo, Fu, Huaqing, Du, Zhi
Research on Sealing and Vibration Reduction Performance of Large Sized Packaging Box2026-99-02027/31/2026
With the continuous development of large precision equipment, the reliability requirement for long-distance transportation is also constantly increasing. Large packaging box with sealing and vibration reduction performance is crucial during transportation. This article introduces the sealing measures for large-sized packaging box, as well as the sealing structure design methods for key parts, vibration reduction measures and the selection and design of vibration dampers. The designed packaging box has been used for long-distance transportation of various types of equipment and the reliability of sealing and vibration reduction performance has been verified in practical applications, providing reference for the design of similar packaging boxes.
Zhang, Ruoyu, Jiang, Shouli
Discussion on Methods for Studying Material Fatigue Life: Taking Aluminum Alloy as An Example2026-99-01217/31/2026
Fatigue design is a key common quality technology for improving the quality control capability of China’s automotive products. The fatigue of materials is a multi-scale damage evolution process. Characterizing and processing the large number of three-dimensional defects inside the material, which have different shapes and distributions, and predicting the material’s lifespan based on the cross-scale damage evolution mechanism, is one of the key technologies for fatigue optimization design. This paper discusses the research methods for the fatigue life of aluminum alloy materials. Firstly, based on the staged fatigue damage experiments, the three-dimensional defect features are obtained through CT scanning and reconstruction, and a defect characterization and processing method based on k-d tree and multi-scale feature pyramid is established to accurately represent the topological and geometric relationships of non-uniformly distributed three-dimensional defects. Secondly, a mathematical model for the evolution of micro-damage and macro-cracks is constructed, and the cross-scale transformation of defects is achieved through hierarchical and recursive methods, revealing the cross-scale evolution mechanism of fatigue damage in aluminum alloy materials. Finally, a remaining life prediction model based on defect information and feature weights is established through the support vector regression algorithm (SVR). This research method can provide technical support for the fatigue life optimization design application of lightweight materials such as aluminum alloys.
Zhang, Liangxia, Niu, Zhijun, Cheng, Fangfang, Chen, Hao, Yang, Yali
Research on Electromagnetic Characteristics Calculation of Small Lead Bismuth Ring Linear Induction Electromagnetic Pump Device2026-99-02017/31/2026
Compared to traditional reactors, lead-bismuth eutectic reactors (LBE) have higher neutron economy and stability. As a device for driving the coolant, the electromagnetic pump features non-contact operation, simplifying the sealing apparatus and achieving complete sealing inside the pump. It meets the requirements of miniaturization and modularity, while offering excellent flow regulation performance. Its input parameters determine the output performance in both performance analysis and structural design of lead-bismuth electromagnetic pumps . This article focuses on a small-scale annular linear induction electromagnetic pump (ALIP) as the simulation object and establishes an electromagnetic pump model. Based on Maxwell’s equations and N-S equations, and with the background of three-dimensional multiphysics coupling of electromagnetic field, flow field and heat transfer field, the coupling mechanism between the flow velocity of LBE and the Lorentz force was studied in detail. From the perspective of electromagnetic-flow coupling, the influence of different coil turns, input currents, and excitation frequencies on the Magnetic flux density and pressure of electromagnetic pumps was analyzed. Finally, a comprehensive analysis of the output characteristics of ALIP under various input parameters is performed, and the research results provide a theoretical reference for the design and optimization of lead-bismuth ALIP.
Peng, Chunyu, Xiao, Changzhi
SiO2 Particle Charging Behavior with a Nonionic Surfactant in Low-Permittivity Liquids2026-99-02247/31/2026
Phase angle light scattering (PALS) was chosen to study the charging behaviors of metal oxide SiO2 distributed in nonpolar solvents, including nonionic surfactant, often known as “charge control agents”. Zeta potential was examined systematically in relation to the concentration of Span80 (Sorbitan monooleate) and particle size and concentration. The findings showed that Zeta potential was unaffected by the surfactant concentration of Span80 over the critical micelle concentration (CMC) at various particle concentrations (volume percentages ranging from 10^–4 to 10^–2). Over a considerable range, the charging of the particles was not significantly affected by the particle concentration. Additionally, the particles showed a size-independent zeta potential. A straightforward model based on meanfield Poisson-Boltzmann theory and preferential adsorption was offered to predict SiO2 particles’ charging procedure in Span80-dodecane solution. The experimental data and the simulated findings agreed well. It was shown that the preferential adsorption of micelles that carry a charge is the cause of the charging of the SiO2 particle in Span80-dodecane solution.
Jiang, Liyuan, Chen, Jiayi, Lv, Qunsong, Cao, Huiying
Research on Takeoff and Cruise Control of Fixed-Wing UAVs in Urban Railway Inspection Scenarios2026-99-08247/30/2026
Urban railways are an important part of China’s rail transit “four network integration”. Their stations are typically situated in suburban regions, characterized by long lines and large station spacing. Traditional manual inspections entail a substantial workload and exhibit low efficiency; multi-rotor UAVs are constrained by limited endurance and airspeed, leading to low efficiency in daily long - range inspections. Fixed-wing UAVs have the advantages of long endurance and high altitude, and are more cost-effective for daily routine inspections when deployed in long areas. They complement the functions of multi-rotor UAVs in rail transit inspection applications. The flight control system of a fixed-wing UAV is a multi-channel, strongly coupled complex system. Based on its lateral and longitudinal dynamic models and navigation technology, this paper designs different types of PID control strategies for the control channels, such as roll angle, pitch angle, altitude, vertical velocity, and flight airspeed, and verifies the feasibility of the control algorithm through numerical simulation. Finally, through on-site test flights, the stability and reliability of the single aircraft flight control system were verified, providing technical support for the availability of fixed-wing unmanned aerial vehicles in the inspection of long sections of urban railways.
Lin, Jing, Deng, Zhixiang, Xu, Jun, Wu, Huankun, Guan, Bin, Liu, Lei
Research on a Lightweight Door Based on an Approximate Model Constructed by a Differentiation Strategy2026-99-08127/30/2026
Taking the front door of a new energy vehicle as the research object, a finite element model was built based on HyperMesh to conduct stiffness and modal performance analysis, and clarify the characteristic differences of multiple responses of the door. To address the issue that traditional single approximation models are difficult to adapt to different response characteristics, a strategy for constructing differentiated approximation models is proposed, which is to select the optimal approximation model according to different response types. The results show that the approximation models for each response constructed based on the differentiation strategy have a fitting accuracy (R^2) of more than 0.99, close to complete fitting, which is significantly better than the overall adaptation effect of a single model. Finally, based on the approximate model established using this strategy, combined with a multi-objective optimization algorithm, the dimensions of the front door are optimized, while achieving lightweighting and performance improvement of the front door, which provides a new idea for constructing multi-response high-precision approximate models.
Wei, Yansai, Shen, Yongfeng
Research on Integrated Design and Optimization Method of High Speed Shuttle UUV Rudder and Propeller2026-99-08647/30/2026
Along with the advancement of the maritime power strategy, the research, development, and application of deep-sea space stations are becoming increasingly important. However, since deep-sea space stations mainly rely on acoustic communication, they cannot exchange information with ground stations quickly and accurately. To improve data transmission efficiency, this paper proposes using a high-speed shuttle UUV instead of acoustic communication. In this context, an efficient propulsion system is critical as it enables the UUV to achieve high speed and maintain stability. A propeller meeting the 110.9 N thrust requirement is designed using the chart design method, and the 110BL230-630 brushless DC motor is selected based on motor–propeller matching. This motor has a rated speed of 3000 rpm, rated power of 3000 W, and torque of 9.6 Nm. The performance curve of the NACA0012 airfoil is analyzed to select an appropriate rudder surface. The rudder area (4067 mm^2) is designed in accordance with DNV rules, with the following parameters: tip chord length 40 mm, root chord length 40 mm, and half-span 70 mm. CFD analysis is conducted on the designed propeller and the UUV equipped with the integrated propulsion system. The predicted performance of the P4119 propeller (hydrodynamic parameter deviation ≤ 1%) and the SUBOFF hull (resistance relative error ≤ 3.04%) confirms the accuracy of the CFD method for calculating propeller open-water performance and UUV drag. Through comparative analysis, the optimal rudder–propeller spacing is determined to be 60 mm, as this spacing yields the highest propulsion efficiency.
Wei, Jiaguang, Feng, Xiaowei, Zhao, Fuchen, Wang, Xingke, Xu, Shanzhi, He, Wenxuan
Research on Long-Life Solid-Liquid Hybrid Lubrication Technology for Large Drive Mechanisms of Survey Platform2026-99-08267/30/2026
For the large drive mechanisms of the survey platform, aiming to achieve long-life in-orbit rotation lubrication, a study was conducted on the tribological characteristics of a lubrication solution combining molybdenum disulfide (MoS2) coating with the application of perfluoropolyether (PFPE) greases. Validation tests were carried out under vacuum and high-low temperature environments to evaluate the equivalent in-orbit service life of solid lubrication coatings when used in conjunction with vacuum greases. Additionally, the physical properties of the friction pairs under solid-liquid hybrid lubrication conditions were investigated. Using life components equivalent to the actual product state, vacuum high-low temperature life tests under solid-liquid lubrication conditions have been completed to validate long-life lubrication technology. This holds significant guiding and reference value for the design of subsequent long-life spacecraft.
Fu, Zhibin, Zhang, Kai, Yang, Siqi, Zhu, Jiahao, Qian, Zhiyuan, Ji, Ming, Zhang, Lei, Wang, Zhiyi, Ma, Zhifei
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