China Mechanical Engineering

A Review of Mechanics Property Studies of Retracting and Releasing Cables for Marine Exploration Equipment

WAN Buyan1, 2, PENG Fenfei1, 2, 3, JIN Yongping1, 2, LIU Deshun1, 2, PENG Youduo1, 2

2024, 35(09): 1521-1533. DOI: 10.3969/j.issn.1004-132X.2024.09.001

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The retracting and releasing cables were the only link between the submarine exploration equipment and the ship, had the functions of power, information transmission and load-bearing, and were widely used in all kinds of launch and recovery systems. The safety and reliability of retracting-releasing cables were of the core functional requirements. Therefore, conducting experiments on mechanics properties of retracting-releasing cables was the foundation of retracting-releasing cable research. Starting from the types and failure modes of ocean winches and retracting-releasing cables, the state of experimental studies of the mechanics properties of retracting-releasing cables was systematically summarized, and an outlook on future research directions was provided. Firstly, the functions of ocean winches and retracting-releasing cables were categorized, followed by a detailed analysis of the forms and reasons for their failures. Secondly, the operating conditions, mechanics performance requirements of retracting-releasing cables, and experimental researchs current status were described. Lastly, the research directions for the mechanics properties of retracting-releasing cables in ocean detection equipment were discussed, including the impact and mechanism of extreme operating environments on mechanics properties of synthetic retracting-releasing cables, the behavior and mechanism of synthetic retracting-releasing cable damage under multiple load couplings, and the technology and integrated simulation devices for retracting-releasing cable mechanics properties.

Research on Driving Style Classification and Recognition Methods Based on Driving Events

QIN Datong, CHEN Moji, CAO Yuhang, GAO Di

2024, 35(09): 1534-1541. DOI: 10.3969/j.issn.1004-132X.2024.09.002

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Aiming at the problems that, based on data statistical characteristics, the classification and recognition method of driving style was easy to ignore the diversity of driving style during driving, a classification and recognition method of driving style was proposed based on driving events, spectral clustering and random forest. Experiments were designed to collect driving data, and the data were preprocessed to extract turning events and braking events. After standardization and dimensionality reduction, the spectral clustering algorithm was used to cluster the driving style of turning events and braking events respectively. The entropy weight method was used to obtain the driving style weights of each driver, and the accuracy of five machine learning algorithms was compared for driving style recognition. Results show that the accuracy of driving style recognition is as 92.73% based on random forest, which significantly improves the accuracy of driving style recognition.

J-A-N Force Magnetic Coupling Mechanism Model under Multi Cycle Dynamic Cyclic Stresses

XING Haiyan, LIU Weinan, CHEN Long, XU Cheng, YI Ming, YAN Junjie

2024, 35(09): 1542-1547. DOI: 10.3969/j.issn.1004-132X.2024.09.003

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At present, force magnetic coupling J-A model did not consider the influences of domain wall thickness and multi cycle dynamic cyclic stresses in pinning fields, which resulted in an overestimation of stress magnetization values in the J-A model that could not accurately describe early fatigue damages. Therefore, based on domain wall theory and Burgers dislocation theory, the domain wall thickness factor was introduced to improve the pinning field equation of the J-A model. Furthermore, factors such as stress amplitude and cycle number of cyclic loads were considered, and a J-A-N force magnetic coupling mechanism model under multi cycle dynamic cyclic stress was established. Magnetization laws were obtained under different dynamic cyclic stress amplitudes σa and mean stress σm. With the same cycle times, the σa mainly affects the stress magnetization rate, while the static mean stress σm mainly affects the stress saturation magnetization size. When the same σm is constant, with the increase of σa, the speed of reaching stress saturation state increases. When the same σa is constant, the stress saturation magnetization decreases with the increase of σm. To verify the effectiveness of the J-A-N model, magnetic field signal detection experiments were conducted on 45 steel three-point bending specimens under multi cycle dynamic cyclic stress, and the experimental results are consistent with the model ones.

Terminal Constraint Analysis of (3-RPS)+(2-RCR) Hybrid Mechanisms

HU Bo1, 2, ZHAO Jinjun1, 2, LIU Jianzheng1, 2, ZONG Hongyi1, 2

2024, 35(09): 1548-1558. DOI: 10.3969/j.issn.1004-132X.2024.09.004

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In order to explore the particularity of terminal constraint form of “parallel+parallel” type lower mobility hybrid mechanisms, taking (3-RPS)+(2-RCR) mechanisms as research object, a method for solving the intersection of screw systems corresponding to terminal constraint issue was proposed. Firstly, the composition principle of terminal constraint/mobility of (3-RPS)+(2-RCR) mechanisms was introduced, and the calculation formula of terminal constraint/mobility was given. Secondly, the number of terminal mobility of the mechanisms was analyzed using line geometry under different geometric configurations. Then, the ruled surface and generatrix equation corresponding to sub-constrained screw systems were established by analytic geometry theory and screw theory, and the intersection analytic model of three-screw system and four-screw system was obtained, and the terminal constraint of the mechanisms was determined. Thirdly, the terminal constraint/mobility properties were discussed under different geometric configurations. Finally, numerical examples of the mechanisms were given to solve the terminal constraint under three different configurations. The results show that terminal constraint of the mechanisms is not a constraint force/couple, but the general form of wrench under the general configuration. The method of solving the intersection of screw systems provides an effective way to solve the terminal constraint problems of this kind of hybrid mechanisms.

Study on Forward Design Process of Screw Type Blind Rivets

FENG Jiaming1, SUN Yuyin1, HE Ying2, JIN Wanjun2, LIAO Ridong1

2024, 35(09): 1559-1566. DOI: 10.3969/j.issn.1004-132X.2024.09.005

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Through theoretical analysis, finite element simulation, and experimental verification, the reverse research from 1 to 0 on basic applications of screw type blind rivets was studied. The evolution and equilibrium of forces during installation processes were established. The relationships of installation performance (preload, diameter and height of blind head) and key geometric parameters were obtained. And a parametric module was developed, which might achieve automatic modeling and simulation calculations. The results have guiding significance for enhancing connection reliability, improving economic benefits, and for promoting the processes of independent research and development of the screw type blind rivets.

Study on Influences of Load on Oil Film Interface Slip and Elastohydrodynamic Lubrication Characteristics

GUO Chuang, ZHAO Erhui, QUAN Long, WANG Chengwen

2024, 35(09): 1567-1574. DOI: 10.3969/j.issn.1004-132X.2024.09.006

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In order to explore formation and evolution mechanism of lubrication failure of friction pair in mechanical transmission system under harsh working conditions, a point contact elastohydrodynamic lubrication model was established considering oil film interface slip, and simulation calculation was carried out. The two-color light interference elastohydrodynamic lubrication test was carried out to study the influences of load on oil film interface slip in elastohydrodynamic lubrication, and then variation characteristics of entrainment velocity, hydrodynamic pressure, oil film thickness and slip parameters with load were studied under interface slip state. The results show that with the increase of load, the slip amplitude and slip range of interface increase significantly and the entrainment velocity in slip region decreases obviously. The dynamic pressure distribution in slip region tends to be uniform. In addition, slip region produces film thickness accumulation and inlet depression characteristics. The shape of slip region gradually presents the characteristics of “half crescent”.

Analytical Algorithm and Structural Optimization of Transmission Characteristics of Cylindrical Permanent Magnet Couplings

ZHANG Jiarui1, HE Tao2, SU Guilong1, LI Yangyang1, LUO Weiqi1, CHENG Xikang1, ZHOU Mengde1, ZHANG Yang1, LIU Wei1

2024, 35(09): 1575-1583. DOI: 10.3969/j.issn.1004-132X.2024.09.007

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The permanent magnet couplings had problems of complex structure, difficult assembly and poor resistance to eccentric load. In terms of transmission performance evaluation, the finite element simulation calculation took a long time and the analytical calculation accuracy was low. Therefore, a new type of cylindrical permanent magnet coupling configuration was designed. The trapezoidal magnet and the wedge slot may realize the self-priming assembly of permanent magnets. Aiming at this configuration, an equivalent magnetic charge-magnetic circuit analytical calculation method was proposed to calculate the transfer torque and an absorption-repulsion composite permanent magnet coupling configuration was designed. The transfer torques where the relative deflection of inner and outer rotors as 0°~45° and the foces responde to radial relative offset -3.8~3.8 mm of two permanent magnet couplings were simulated and verified by experiments. The results show that the errors of the proposed analytical algorithm decreases 50% than that of the simulation results, and the analytical calculation time is shortened from 2 h to 2 min. Compared with cylindrical configuration, the maximum radial eccentric load of the suction-repulsion composite configuration is as 48.59%. Reasonable suggestions are put forward for design optimization of permanent magnet couplings.

Research and Device Design of Coal Mine Mechanical Impact Behaviors Based on Energy Distribution Principle

CHAI Rongxia1, JIANG Xiaoyuan1, WANG Qinsheng2, YU Zhengyang3, LONG Xue1, LIU Jun1

2024, 35(09): 1584-1596. DOI: 10.3969/j.issn.1004-132X.2024.09.008

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To study the impact damage behaviors of coal mining machinery during service, the horizontal impact of a spherical projectile on a metallic rectangular plate was used as a case study to derive the energy distribution relationship during impact processes. In line with the actual impact conditions, a pneumatic horizontal impact testing system was designed and constructed to capture the impact response of plates under varying air pressures. Through simulations and experiments, the theoretically calculated deformation and acceleration were validated, and a polynomial fitting approach was used to optimize the acceleration of output parameters. The computations, experiments, and simulations were compared. Results show that the kinetic energy of the projectile is primarily expended on plastic deformation of material, kinetic energy of motion, and collision loss during impact. When the central region of impacted plate fractures, the energy dissipates through plastic deformation and collision loss decreases. The refined theoretical, experimental, and simulation results for energy distribution relationship show good agreement during the impact processes, with a maximum deviation of less than 9.39%.

Hysteresis Modeling and Feedforward Control for Piezoelectric Driven Systems Based on Rayleigh-BP Model

ZHANG Meng, FAN Pengju, WANG Junpu, LIU Shicheng

2024, 35(09): 1597-1605. DOI: 10.3969/j.issn.1004-132X.2024.09.009

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Aiming at the hysteresis nonlinearity of the piezoelectric driven systems for tunable external cavity diode lasers, a modelling and control method was proposed herein based on Rayleigh-BP model. Firstly, a Rayleigh-BP rate-dependent hysteresis model was developed by spatial expansion method, which achieved an accurate prediction of rate-dependent hysteresis nonlinearity of piezoelectric driven systems. Secondly, the inverse model of Rayleigh model was solved by an inverse algorithm, and the model was combined with a BP neural network to design a feedforward controller to compensate the systems. Finally, the feedforward control method was validated by simulation and experiments. The results show that the Rayleigh-BP model developed has high accuracy, the root mean square error is only as 0.0469 μm at 10 Hz. The feedforward control method may significantly improve the linearity of the system outputs, the root mean square error of the simulation results is as 0.0274 μm and the linear correlation coefficient R2 is as 0.999 92 at 40 Hz. The experimental results show a root mean square error of 0.0506 μm and a linear correlation coefficient R2 of 0.999 55 at 30 Hz, which greatly reduces the hysteresis phenomenon.

Experimental Study of Figuring and Polishing of Titanium Alloy Blades with Fixed Abrasive Tools

XU Chengyu, ZHANG Wanyi, ZHANG Tianhong, ZHU Yongwei

2024, 35(09): 1606-1612. DOI: 10.3969/j.issn.1004-132X.2024.09.010

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To improve the surface quality and profile accuracy of non-uniform allowance titanium alloy blades, a new method of integrating the figuring and polishing of titanium alloy blades was proposed based on fixed abrasive tool technology. The distribution of machining allowances of titanium alloy blades was obtained according to spatial relative position relationship among the theoretical trajectory points and the actual measurement points of processing blades. The principle of deterministic polishing was used to establish the quantitative removal model of blade surfaces. The figuring and polishing of titanium alloy blade experiments were carried out on robot constant force polishing platform. Experimental results show that the average roughness of titanium blade basin decreases from 0.924 μm to 0.225 μm, and the average roughness of blade back decreases from 0.984 μm to 0.249 μm. Both of which meet the processing requirements of less than 0.4 μm. The original pits and scratches on the blade surfaces are effectively removed. There are no obvious defects on the machined surfaces and the texture is dense and uniform. The profile errors of the polished blades are less than the allowed range of -0.05~0.05 mm for the blades. The feasibility of the figuring and polishing of titanium alloy blades with non-uniform allowance of the fixed abrasive tool is verified, which provides a reference basis for the processing selection of figuring and polishing of aero-engine blades.

Self-driven Independent Degradation Trajectory Construction and Remaining Life Gray Prediction for Bearings

LIU Xiaofeng, KANG Yingying , BO Lin

2024, 35(09): 1613-1621，1652. DOI: 10.3969/j.issn.1004-132X.2024.09.011

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To address the problems of individual variability of bearing degradation trajectories and artificial subjectivity of degradation stage division, a self-monitoring data-driven extraction method of independent bearing degradation trajectory and an autonomous segmentation technique of degradation stages were proposed. A multiscale residual deep convolutional autoencode was developed herein to autonomously extract the bearing performance degradation features by unsupervised learning of bearings own historical monitoring data, and then combined with support vector data description model to construct single bearing independent degradation trajectory. The de-trending super-threshold waveform method was introduced to automatically detect the starting degradation point, and the failure threshold was set autonomously using logistic regression-based failure probability statistics method, thus the bearing independent degradation trajectory was adaptively segmented. Driven by degradation stage index obtained from trajectory segmentation, the accurate prediction of bearing life was achieved by combining full time power gray prediction model. The experimental results show that the multiscale residual deep convolutional autoencode network proposed herein may construct a degradation trajectory reflecting the degradation law of the bearing itself according to the respective working conditions of the bearings, and the adaptive degradation trajectory segmentation method proposed herein may detect the starting degradation point and the failure threshold of the bearing without references. The results may improve the scientific objectivity of bearing degradation assessment and the engineering operability of life prediction.

Bearing Fault Diagnosis Method Based on Intensive Distribution Alignment with Open Set Difference

LI Can1, 2, WANG Guangbin2, 1, ZHAO Shubiao1, 2, ZHONG Zhixian1, ZHANG Hui1, 2

2024, 35(09): 1622-1633. DOI: 10.3969/j.issn.1004-132X.2024.09.012

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In view of the facts that the current transfer learning algorithm was applied to the field of bearing fault diagnosis, there might be unknown fault categories in the target domain, which led to the problems of low recognition accuracy, and an open set domain adaptive method was introduced. Aiming at the problems that the existing open set domain adaptive algorithm paid more attentions to cross-domain alignment and paid little attention to the distribution within the domain when performing distribution alignment, which led to the low recognition rate of unknown categories. A method was proposed based on intensive distribution alignment with open set difference(IDAOD), which integrated cross-domain divergence alignment and intra-domain distribution alienation method. Firstly, the open set nearest neighbor class verification method was used to obtain the pseudo-label of the target domain. Then, the overall divergence matrix of the source domain and the target domain was constructed, and the cross-domain divergence alignment was performed. Based on the distribution adaptation weighted conditional distribution, the spatial distribution of different categories was further alienated in the same domain. Finally, under the framework of structural risk minimization, the loss function constructed was introduced based on the open set difference theory, and the regularization term was introduced to obtain the optimal solution and the new target domain pseudo-label. The feasibility of the IDAOD algorithm was verified by experiments on Office-31 dataset. The fault diagnosis experiments were carried out on CWRU and JNU bearing data sets respectively, and the recognition rate of unknown fault category is higher than that of other comparative open set algorithms. It is verified that the method proposed herein may effectively improve the accuracy of the bearing data set when target sample contains unknown samples.

Label Assignment Algorithm for Metal Defect Samples Based on Distance-awareness

ZHU Chuanjun1, LIANG Zeqi1, FU Qiang1, ZHANG Chaoyong2

2024, 35(09): 1634-1641. DOI: 10.3969/j.issn.1004-132X.2024.09.013

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The distance-aware dynamic label assignment(DDA) algorithm was proposed to address issues such as the lack of consideration for aspect ratio of metal surface defects and poor localization ability towards target distribution during the allocation of positive and negative samples in training processes of metal surface defect detection model. DDA did not change the structures of original detection model and did not increase computational expenses. A new distance loss calculation paradigm was proposed based on geometric characteristics of real frame to optimize the regression problem with a wide aspect ratio. The regression offset in iterative processes was decoded as predicted frame coordinates. Finally, the comprehensive intersection and union ratio information were calculated among the predicted frame, anchor frame and real frame, and positive and negative samples were dynamically selected to improve training accuracy. It was verified through the surface defect detection task of cold-rolled strip in a steel plant in Wuhan, and a public hot-rolled strip surface defect data set was introduced for generalization testing. The detection results are significantly improved, which has practical application values for metal surface quality specifications.

Analysis of Compressive Mechanics Properties of Body Centered Cubic Lattice with Pillars in Different Reinforcement Directions and Their Filling Structures

ZHANG Wukun1, 2, ZHAO Jian2, TAN Yonghua1, 2, GAO Yushan1, 2, WANG Jun1, 2, HAN Ziyue3, GENG Xiaoliang4

2024, 35(09): 1642-1652. DOI: 10.3969/j.issn.1004-132X.2024.09.014

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To study the compressive mechanics properties of pillar centered cubic lattice with different reinforcement directions and their filling structures, silicone rubber filled lattice structure test specimens were prepared herein. The compressive mechanics properties of two lattice structures(BCC1 or BCC2, loading direction was either the same or perpendicular to the direction of pillar rod in body centered cubic lattice with pillars) filled with silicone rubber were studied through experimental and simulation methods. The equivalent elastic modulus and compressive platform stress of two lattice structures were conducted using Timoshenko beam theory and ultimate load method. The results indicate that the proposed theoretical model may effectively predict the equivalent elastic modulus and compressive platform stress of two type lattice structures. After filling, the compression strength and energy absorption performance of the two lattice structures are enhanced, while the enhancement effect of the BCC2 structure is more significant. For the BCC1 lattice, rubber filling enhances the bearing capacity of the internal members. However, for the BCC2 lattice structure, rubber filling reduces the bending deformation of the members near the V-shaped shear band. As the radius of the lattice structure increases, the energy absorption coupling factors of both lattice structures first increase and then decrease, yet the energy absorption coupling factor of BCC1 type structure changes more significantly.

Simulation and Experimental Study of Deformation Control of Large-size and Thin-wall Parts by SLM

ZHANG Luo1, LIU Mingming2, CHEN Ruimin1, DAN Peng1, GUO Nan1

2024, 35(09): 1653-1658，1709. DOI: 10.3969/j.issn.1004-132X.2024.09.015

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Simulate Additive software was used to simulate and analyze the additive manufacturing processes of a typical large-sized thin-walled component—exhaust pipe. The results show that the SLM formed exhaust pipe parts without constraints have high residual stress and significant deformation. The post-processing releases residual stress in the parts, but the overall deformation of the parts further increases to 3.5 mm, with a maximum deformation of 9 mm. A lattice structure was introduced with high specific strength and stiffness as an auxiliary structure for controlling deformations, and a lattice processing scheme was designed with sufficient resistance to deformation and may be removed through post-processing. The cell type is QuadDiamond, the rod diameter is as 1.3 mm, the rod length is as 19 mm, and the width of the lattice region is about 60 mm. The SLM test results of the exhaust pipe parts under lattice constraints are quite consistent with the numerical simulation results. The cloud image results of the three-dimensional scanning show that the overall deformation of the part is about 1 mm, and the maximum deformation does not exceed 2.5 mm, meeting the requirements for the part use. The above results show the effectiveness of using lattice structure in deformation control of large-sized thin-walled parts formed by SLM.

Material Removal Model of Center-inlet Elastic Polishing Tools

JIN Minglei1, 2, JIN Mingsheng1, 2, SONG Zhengjiang3, ZENG Xi1, 2, LI Yan1, 2, TANG Xuan1, 2

2024, 35(09): 1659-1666. DOI: 10.3969/j.issn.1004-132X.2024.09.016

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In order to enhance the deterministic processing capability of computer controlled optical surface(CCOS) forming technology, a center-inlet elastic polishing tool(CEPT)was proposed herein. Based on the structural characteristics of CEPT and the stress field model contacting with the workpieces, the radial contact stress distribution of CEPT before and after attaching diamond resin sandpaper was studied. It is found that after attaching sandpaper, the CEPT has a smoother radial contact stress distribution and a larger contact stress amplitude. Subsequently, the contact stress and velocity distribution functions of CEPT were constructed under continuous feeding conditions, and a material removal model for CEPT was established based on Preston equation. Finally, polishing experiments and single factor comparative experiments were conducted to obtain the distribution of material removal depth and the relationship between key processing parameters and material removal depth of CEPT. The experimental results show that the average deviation between material removal model constructed herein and the actual material removal profile is less than 10%, which may better predict the actual material removal depth of CEPT.

DEM-FEM Coupled Simulation and Experimental Study of Residual Stresses in Horizontal Vibratory Finishing Processes

TIAN Tao1, 3, LI Wenhui2, 3, 4, WEN Xuejie1, 3, LI Xiuhong1, 3, YANG Shengqiang1, 3

2024, 35(09): 1667-1676. DOI: 10.3969/j.issn.1004-132X.2024.09.017

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To investigate the influences of horizontal vibratory finishing on the residual stress of part surfaces, a coupled DEM-FEM simulation method applicable to dynamic parts was proposed. The particle motion states and the changes of average contact force among particles were analyzed during the vibration cycle, and a random contact model between particles and parts was constructed to carry out the simulation of residual stresses of vibratory finishing with different vibration parameters, and experimental validation was carried out. The results show that with the increase of vibration intensity, the particle motions in the container are more intense, and the probability of occurrence and the mean value of the effective normal contact force between the particles and the parts increases, resulting in an increasing trend of the residual compressive stress on the surfaces of the parts. The simulated and the experimental values of residual stress show the same response trends to the vibration parameters, with the errors ranging from 3.6% to 11.3%.

Three-dimensional Positioning Guidance of Automobile Doors Based on Machine Vision

NA Yiming1, HU Chao1, QIU Yeyu2, LU Libing2, SONG Kai1

2024, 35(09): 1677-1687. DOI: 10.3969/j.issn.1004-132X.2024.09.018

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At present, in workshops, parts fixed on fixtures were commonly guided and gripped by pre-teaching the motion trajectories of robotic arms, resulting in poor human-machine interaction and low levels of intelligence. Machine vision, as an effective means of non-contact sensing and measurement, was applied in industrial scenarios. Based on monocular vision pose measurement technology, a multi-camera PnP positioning model and robotic arm guiding model were established to achieve spatial perception and guided grasping of the parts. Additionally, a pre-calibration method was proposed using multi-zero anchors to compensate system errors between robotic arm and vision module, which effectively decreasing the positioning and guiding errors of large parts.

High-resolution Microscope Motion Control Based on Adaptive Finite-time Control Strategy

YU Shengdong1, 2, 3, LI Xiaopeng1, 2, YANG Sipeng2, WU Hongyuan1, 2, HU Wenke1, 2, CAI Bofan1, 2, MA Jinyu3

2024, 35(09): 1688-1697. DOI: 10.3969/j.issn.1004-132X.2024.09.019

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A nonlinear robust motion control strategy was proposed to achieve precise movement of objective motion carrier in context of large numerical aperture microscopy imaging technology, which required a long stroke, high precision, and large load capabilities. An optical path system and a virtual prototype of a large numerical aperture microscope were designed. In addition, a ball-screw-driven objective motion carrier was designed, and the backlash of ball-screw was eliminated by double nut preloading method. To achieve finite-time convergence of system state and improve system robustness, an adaptive technology was employed in nonsingular terminal sliding mode control. Furthermore, to address nonlinear friction effect in ball-screw transmission mechanisms, TDE technology was employed to realize online estimation and real-time compensation of friction forces. TDE technology and adaptive nonsingular terminal sliding mode control were adopted to achieve model-free control characteristics. The stability of closed-loop system was proved by Lyapunov theory. Consequently, a high-resolution optical microscope was developed to achieve precise movement of objective motion carrier, and microscopic images of mouse cardiac muscle cells were acquired to demonstrate the effectiveness of the proposed algorithm.

Time-domain TPA Method Based on AKFZ

HU Yu1, HE Zhicheng1, ZHAO Liang2

2024, 35(09): 1698-1709. DOI: 10.3969/j.issn.1004-132X.2024.09.020

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When time-domain TPA methods used for tackling vibrations and noise problems in complex systems during transient conditions, which failed to overcome the ill-conditioned problems of the frequency response functions matrix near natural frequencies, and showed low accuracy in extracting the required time-domain information from the existing frequency-domain data. Therefore, a new time-domain TPA method was developed based on AKF. This method started with estimating time-domain operational loads using AKF supplemented by GA, and then identified the impulse response functions using LS algorithm. Finally, time-domain contributions for each transfer path was computed by linearly convolving time-domain operational loads with respective impulse response functions. Case study demonstrates that the load-identification errors of AKF applied in the proposed method are smaller than that of traditional deconvolution filters. Additionally, the errors of impulse response functions identified by LS algorithm are smaller than those obtained by direct inverse fast Fourier transform or creating finite impulse response filters from frequency response functions. Furthermore, the proposed method achieves small errors even in complex structures.

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