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IEEE International Conference on Robotics and Biomimetics

作者： Tianbo Lan Jiang Ding Jingyu Li Fengran Xie Kai He Qiyang Zuo Guangxi Key Laboratory of Manufacturing System and Advanced Manufacturing Technology School of Mechanical Engineering Guangxi University Nanning China Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi University Nanning China School of Artificial Intelligence Shenzhen Polytechnic University Shenzhen China

ISBN: (数字)9798331509644

ISBN: (纸本)9798331509651

This paper presents a novel biomimetic rudder-controlled autonomous underwater vehicle (BRCAUV) that is capable of operating at all speed range (i.e. including high, medium, low, and even zero speeds) for both wide-area cruising and localized fine observation tasks. This AUV integrates a top rudder, a propeller, and two-degree-of-freedom (DOF) biomimetic rudder wings on both sides of the aft section, enabling it to perform various tasks in a single underwater operation. These tasks include wide-area cruising at medium to high speeds and fine observation at low and even zero speeds. The prototype is equipped with a propeller, a biomimetic dorsal fin, two pectoral fins(i.e. two-DOF biomimetic rudder wings), and a buoyancy regulation system. At medium to high speeds, the AUV utilizes a combination of the propeller and pectoral fin movements for ascent and descent. At low or zero speeds, the biomimetic pectoral fins are used for complex maneuvers such as buoyancy adjustment, roll, and pitch. This paper develops a dynamic model of the pectoral fins based on quasi-steady theory, elucidating the principles of low-speed steering. Experimental were carried out and the results validate the prototype's low-speed steering capabilities, so that new approaches were presented to enhance the maneuverability, multifunctionality, and practicality for underwater vehicles.

关键词： Autonomous underwater vehicles Technological innovation Propellers Biomimetics Biological system modeling Robot kinematics Prototypes Buoyancy Turning Vehicle dynamics

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Design and Analysis of the Cooling Effect of the Temperature-Controlled Pile (Tcp) in Permafrost Regions

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SSRN 2022年

作者： Sun, Zhaohui Liu, Jiankun Hu, Tianfei You, Tian Fang, Jianhong School of Civil Engineering Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory Zhuhai519082 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Qinghai Research Institute of Transportation Xining810001 China

To accelerate the refreezing time of cast-in-place piles in permafrost regions and improve their long-term stability, this paper proposes a novel TCP based on solar refrigeration. The TCP consists of a solar power system (SPS), a vapor compression refrigeration system (VCRS), and a pile. Then, the cooling effect of TCP was carried out by the model test and the numerical simulation. The model test results show that both the evaporating temperature and the condensing temperature are positively correlated with the ambient temperature, but the coefficient of performance (COP) is negatively correlated with the ambient temperature. The numerical simulation results show the TCP can significantly shorten the refreezing time. The higher the mean annual ground temperature (MGAT), the more significant the acceleration effect. With the increase in the TCP working time, the pile wall permafrost temperature tends to be stable, and the cooling radius increases continuously. The TCP can restrain the degradation rate of the permafrost table, which can be further reduced by increasing the refrigeration power and the refrigeration tube space. The tangential freezing force between the frozen soil and the pile foundation is enhanced by the cooling effect of TCP and is stronger when it is close to the middle of the pile. The TCP bearing capacity is more than 1.5 times that of a traditional pile (TP). The effect of improving the bearing capacity of the pile foundation can be achieved by increasing the refrigeration power and refrigeration tube space. Therefore, TCP can be applied to pile engineering of high-speed railways and highways in permafrost regions. © 2022, The Authors. All rights reserved.

关键词： Piles

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Effect of fractional-order PID controller with displacement feedback on the dynamics of spur gear

Effect of fractional-order PID controller with displacement ...

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第八届国际振动工程会议

作者： Jingyu Hou Shaopu Yang Qiang Li Yongqiang Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University

A torsional vibration model of spur gear is built up with considering the effect of the time-varying mesh stiffness, backlash and static transmission error. In order to reduce and control the level of vibration, the fractional-order calculus was introduced into the traditional proportional-integral-derivative(PID) control system and the nonlinear dynamic model of gear transmission based on fractional-order PID(FOPID) controller with displacement feedback is presented. The higher-precision approximate periodic solution of this system is derived by using the incremental harmonic balance method(IHBM). Finally, the influence of the coefficients and fractional order of each link of FOPID controller with displacement feedback on the meshing vibration characteristics of the gear transmission is analyzed in detail by means of amplitude-frequency response curve. Meanwhile, the response of the system with FOPID controller is compared with that of integer-order PID controller and without PID controller. The results show that the control performance of FOPID controller is apparently better than that of integer-order PID controller. Therefore, the FOPID controller with displacement feedback is applied to investigate nonlinear behavior of gear during the meshing, which would provide a certain theoretical basis and instruction for the control of vibration and noise in the mechanical transmission.

关键词： red Effect of fractional-order PID controller with displacement feedback on the dynamics of spur gear

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Nonlinear dynamic response characteristics of SD oscillator with fractional damping

Nonlinear dynamic response characteristics of SD oscillator ...

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第八届国际振动工程会议

作者： Enli Chen Minghao Wang Meiqi Wang Yujian Chang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University School of Electrical and Electronic Engineering Shijiazhuang Tiedao University

The internal friction can be described more accurately by fractional damping than integral damping. The nonlinear dynamic response characteristics of SD oscillator with fractional damping under harmonic excitation are studied. The Fourier equivalent model is proposed to solve the nonlinear stiffness of the differential equation of system motion. The non-integrable nonlinear stiffness of the differential equation of the system is solved. The expression of amplitude-frequency response is obtained by solving the differential equation of system motion using the average method,and the stability of periodic solution is determined based on the Lyapunov stability theory and the Routh criterion. The results show the Fourier transform equivalent model of the nonlinear stiffness term of the SD oscillator can be applied to the motion characteristic of the system with large amplitude, which greatly improves the calculation accuracy. With the same damping coefficient, the amplitude-frequency response of the fractional damping system is different from that of the integral damping system, the resonance frequency and amplitude of the fractional damping system vary greatly. Changing the fractional coefficient will change the amplitude-frequency response backbone curve of the fractional damping system, but the integral damping system is not affected. When the fractional order is changed, the amplitude of the fractional damping system changes opposite on both sides of the cut-off point.

关键词： SD oscillator fractional damping backbone curve nonlinear vibration

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Experimental Study on Shear Strength Characteristics of Frozen Soil - Cast-in-Situ Concrete Interface

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SSRN 2022年

作者： Sun, Tiecheng Dong, Chuangqi Zhang, Jiao Zong, Zihang Wu, Kai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Key Laboratory of Roads and Railway Engineering Safety Control Ministry of Education Shijiazhuang050043 China Hebei Province Technology and Innovation Center on Intelligent Construction of Infrastructure Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China

The roughness of contact surface is closely related to the friction coefficient and shear strength characteristics of pile-soil interface. At present, there is no recognized and unified quantitative characterization method of contact surface roughness. In this paper, the roughness formula is corrected in combination with the proposed form factor, and the low temperature direct shear test of the frozen soil-cast-in-situ concrete interface is carried out. The influence of several test factors, such as contact surface roughness, normal pressure and moisture content of soil sample, on frozen shear strength of frozen soil-cast-in-situ concrete contact surface is analyzed. The test results show that: (a) The frozen shear strength at the contact surface is mainly determined by the cementation of ice cementation force, cohesion and the bite force between frozen soil and concrete. The roughness corrected by the form coefficient can accurately characterize the contribution of bite force to the frozen shear strength of the contact surface. (b) The primary and secondary order of the influence of test control factors on the frozen shear strength of contact surface is normal pressure > moisture content of soil sample > test temperature > roughness > dry density. The normal pressure and moisture content have a strong and significant influence on the test results, the influence of dry density is not significant, and the influence of test temperature and roughness is in the middle. (c) The frozen shear strength of the contact surface increases with the increase of roughness, but the increase of normal pressure can weaken the effect of roughness on the enhancement of shear strength. © 2022, The Authors. All rights reserved.

关键词： Temperature

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Solar Energy-Based Active Heating Method for Frost-Resistant Embankments: A Case Study in China

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SSRN 2022年

作者： Hu, Tianfei Sun, Tiecheng Wang, Tengfei Zhang, Zongkai Wang, Li State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University 17 Northeast Second Inner Ring Hebei Province Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong University Chengdu610031 China

The primary objective of this study is to address embankment frost heave issues in cold regions with an active heating method. A real-time and efficient method of solar heating is developed based on the concept of actively controlling the balance between heat absorption and heat loss. The applicability of various heat sources was compared with the heating demands of embankment. The case study demonstrates that the seasonally frozen areas of China are rich in solar energy resources. A dedicated embankment heating device was designed, including a solar collector section and an embankment heater section. The device integrates energy conversion, storage, and transfer without any moving part, and thus can be used in an "isolated island" scenario for self-driven operations. Performance tests showed that the maximum heating temperature exceeds 60 °C, with an average range of 20–40 °C, which increases with solar radiation. The effective heat utilization rate of soil is approximately 26%. A predictive model that considers latitude and daily ordinal number was proposed for heating temperature. A numerical simulation of the actual embankment long-term heating performance was performed. The results revealed that the heating mode in all seasons could effectively enhance the potential of frost-resistant embankments in winter. © 2022, The Authors. All rights reserved.

关键词： Solar energy

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Wheelset Bearing Fault Diagnosis Method Based on a Novel Parameter-Adaptive Vmd

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SSRN 2022年

作者： Li, Cuixing Liu, Yongqiang Liao, Yingying State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China School of Civil Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China

The traditional parameter-adaptive VMD method uses an advanced meta-heuristic algorithm to determine the two key parameters of mode number and penalty factor adaptively, but this method has the deficiency of a long time-consuming. To solve this problem, a novel parameter-adaptive VMD method is proposed in this paper, which uses the PSO to optimize the initial center frequency and the penalty factor. The single-mode VMD has a strong convergence and can converge to the optimal center frequency as long as the initial center frequency is in the U-shaped range. With this characteristic of VMD, we propose an improved PSO. The correctness of the proposed method is verified by analyzing the fault signals of two sets of wheelset bearings. Compared with the traditional parameter-adaptive VMD method and the EEMD method, the results show that the proposed method has outstanding advantages in fault feature extraction and operation efficiency. © 2022, The Authors. All rights reserved.

关键词： Failure analysis

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Compressive and Flexural Properties and Damage Modes of Aluminum Foam/Epoxy Resin Interpenetrating Phase Composites Reinforced by Silica Powder

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SSRN 2024年

作者： Su, Mingming Zhou, Zhiming Wang, Han Non-destructive Testing Laboratory School of Quality and Technical Supervision Hebei University Baoding071002 China National and Local Joint Engineering Research Center of Metrology Instrument and System Hebei University Baoding071002 China Hebei Key Laboratory of Energy Metering and Safety Testing Technology Hebei University Baoding071002 China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace Engineering Xi'an Jiaotong University Xi’an710049 China

Interpenetrating phase composites (IPCs) were prepared by connecting open-cell aluminum foam (AF) and epoxy resin (EP) in three-dimensional space. Silica powder was added to epoxy resin to improve the compressive and three-point bending properties of IPCs. In the bending test, acoustic emission (AE) was applied to track the bending deformation of the samples, and k-means clustering algorithm was applied to identify the damage modes. When the content of silica powder was 100 wt.%, the compressive and bending properties of IPCs were the highest. The X-type shear band and EP/AF debonding appeared in compression failures of AF and IPCs, respectively. The AE clustering results showed that under bending load, AF contained plastic deformation of matrix and fracture failure modes, while IPCs included plastic deformation of foam matrix, EP/AF debonding and EP failure modes. © 2024, The Authors. All rights reserved.

关键词： Epoxy resins

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Effects of the Cuo Additive Nanoparticles on the Internal Strain Homogenization and Microstructure Evolution in Ag-Sno2 Composites

SSRN

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SSRN 2022年

作者： Li, Guijing Ma, Yuanyuan Feng, Wenjie Zhang, Chuanzeng Yan, Zhen Fang, Xueqian Tian, Ruilan Shijiazhuang Tiedao University Shijiazhuang050043 China Provincial Collaborative Innovation Center of Mechanics of Intelligent Materials Hebei China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures China Department of Civil Engineering University of Siegen SiegenD-57068 Germany Department of Engineering Mechanics Germany

Stress concentration caused by reinforcements has very unfavorable effects on the metal matrix composites, which will inevitably induce localized strains and crack initiation. In this paper, an effective approach is presented to relieve stress concentrations near the reinforcements in metallic composites. The Ag-SnO2 contact materials with CuO additive are prepared by electroless plating combined with powder metallurgy method. The CuO nanoparticles in-situ formed on the SnO2 reinforcements are adopted to relieve local stress concentrations near the Ag/SnO2 interfaces and promote strain homogenization. The mechanical properties, deformation characteristics and microstructure evolution of the Ag-SnO2 composites without and with CuO additive are systematically studied by experiments and numerical simulations. The results show that the CuO nanoparticles formed on the surfaces of the SnO2 reinforcements dramatically improve the mechanical properties of the Ag-SnO2 composites, particularly the plasticity at a higher loading rate. It is demonstrated that the dislocation tangle around the CuO nanoparticles effectively relieves the adverse effect of the stress concentration near the SnO2 and results in the strain homogenization in the Ag matrix. Furthermore, the damage evolution of the Ag-SnO2 composites without and with CuO nanoparticles is investigated by the Gurson-Tvergaard-Needleman (GTN) models under uniaxial tension. The nucleation and growth of voids at the interfaces of the Ag-SnO2 composites are numerically simulated and discussed. This study provides a fundamental basis for developing novel high-performance metal matrix composites. © 2022, The Authors. All rights reserved.

关键词： Stress concentration

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A mechanism-data dual-driven approach for predicting profile changes in rails

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Wear 2025年 578-579卷

作者： Yadi Yang Jianxi Wang Yang Li Wenjie An Jiasheng Cai Key Laboratory of Roads and Railway Engineering Safety Control Ministry of Education Shijiazhuang Tiedao University Shijiazhuang 050043 PR China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 PR China

Accurate prediction of rail profile changes is crucial for scientifically formulating rail wear mitigation strategies, maintaining track reliability, and ensuring economic benefit. However, traditional models based on rail wear mechanisms are limited in prediction accuracy due to their idealized assumptions. While possessing strong nonlinear fitting capabilities, data-driven models often lack interpretability and rely on large amounts of high-quality training data. To address these challenges, this paper proposes a novel method that integrates the advantages of both approaches to predict rail profile changes. Utilizing a prototype network, a rail profile change model is pre-trained with simulation data and then fine-tuned using measurement rail profile data through transfer learning. K-fold cross-validation and noise augmentation are employed to enhance the model's prediction accuracy and robustness. The study results indicate that for tracks with curve radii between 400 and 600 m, the precision of 10 random prediction trials exceeds 90 %, with standard deviations of Mean Squared Error ( MSE ), Root Mean Squared Error ( RMSE ), Mean Absolute Error ( MAE ), and Mean Absolute Percentage Error ( MAPE ) being 0.03397 mm 2 , 0.04261 mm, 0.0204 mm, and 0.175 %, respectively, demonstrating excellent predictive accuracy and stability. Compared to models using only measurement data, this method achieves reductions in average MSE , RMSE , MAE , and MAPE by 30.60 %, 11.76 %, 12.94 %, and 10.45 %, respectively.

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