Table of Content

25 November 2023, Volume 51 Issue 11

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Contents



2023, 51(11):  0. 

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Electronics, Communication & Automation Technology

A Bandwidth Allocation Method of AVB Traffic Based on Link Load Balancing in TSN



LU Yiqin, XIONG Xin, WANG Meng, et al.

2023, 51(11):  1-9.  doi:10.12141/j.issn.1000-565X.220769

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As a new generation technology of Ethernet, time sensitive networking (TSN) plays an increasingly important role in industrial control, vehicle network and other fields, as it guarantees low-delay and low-jitter transmission of time sensitive traffic. As one of the key shaping technologies of TSN, credit-based shaping (CBS) guarantees the deterministic transmission of audio video bridging (AVB) traffic by reserving bandwidth. The existing bandwidth allocation methods based on network calculus mostly do not consider the impact of routing on the schedulability of AVB traffic, and the bandwidth allocation results are poor and the solution time is long when the network is in a large scale. Therefore, this paper proposed a bandwidth allocation method based on link load balancing. Firstly, the link load balancing routing algorithm was used to calculate the optimal path for each AVB traffic. Then, based on the flow path and network calculus, the arrival and service curves of each switch’s outbound port traffic were analyzed to obtain the worst-case forwarding delay. Finally, the optimization objectives and constraints for bandwidth allocation were established, a heuristic algorithm was used to solve bandwidth allocation, and the bandwidth parameter configuration was optimized during the solving process. The experimental results show that the AVB traffic bandwidth allocation method based on link load balancing can improve the schedulability of AVB traffic by 15 to 45 percentage points, compared with existing bandwidth allocation methods. Optimizing parameter configuration can increase the bandwidth solving speed by more than twice and obtain better bandwidth allocation results, which can effectively cope with large-scale dynamic changes in TSN networks.

Simulation Study on BER Performance of DS-UsWB Intrabody Communication



LIU Jiaojiao, CHEN Ayue, MA Biyun

2023, 51(11):  10-17.  doi:10.12141/j.issn.1000-565X.220797

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The water content of human soft tissues is as high as 65%, so ultrasound has advantages in low attenuation, low risk of disease, and limited interference range in human soft tissues, making it advantageous for communication in the body. However, the ultrasonic human channel has the characteristics of dense multipath, so the signals that reach the receiver through multiple paths of reflection and refraction overlap to generate multipath interference, which affects communication reliability. The existing research avoids multipath overlap and its interference by emitting extremely short pulses of ultrasound, but it is difficult to achieve ultra wideband ultrasound probes with large directional angles. The actual pulse width generated by the probe is not small enough, so multipath overlap will occur at the receiver and the interference cannot be ignored in signal judgment. In order to study the distribution characteristics of multipath interference in the body and its impact on wideband ultrasound human body communication, this paper used the k-Wave simulation toolkit to model the ultrasound human body channel in 3D. Then the channel impulse response was obtained through simulation experiments, and the statistical characteristics of multipath delay distribution were analyzed and curve fitting was performed. Based on the decision mechanism of the receiver, the multipath interference of the human channel was estimated, and the lower bound of the bit error rate (BER) for direct sequence spread spectrum ultrasonic broadband (DS-UsWB) was derived. The effectiveness of this lower bound of BER was verified through Monte Carlo experiments. Experimental results indicate that multipath interference cannot be ignored when the signal-to-noise ratio is low, and the communication performance can be improved by adjusting spread spectrum code length.

Multidimensional Cross-Layer Bandwidth Prediction for Low-Latency Real-Time Video



CHEN Feng, MAO Haobin, CAI Jiling, et al.

2023, 51(11):  18-27.  doi:10.12141/j.issn.1000-565X.220705

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The available bandwidth of 5G networks is a pivotal factor influencing real-time video services. However, how to achieve accurate predictions in the context of low-latency real-time video services remains a difficult problem. Conventional algorithms for predicting available bandwidth typically rely on data metrics at the application layer and complete the forecast according to the packet transmission strategies. Such algorithms can lead to prediction lag in complex scenarios, thereby significantly impairing the received video quality for users. To address this concern, this study proposed a novel available bandwidth prediction algorithm based on cross-layer multi-dimensional parameters. This algorithm comprehensively integrates pertinent data metrics from the application, physical, and network layers, utilizes multiple dimensions of parameters to enhance the precision of wireless network bandwidth detection. In this paper, deep reinforcement learning was adopted as the model framework to integrate offline prediction and online prediction through cross-layer and multi-dimensional data model learning for different motion scenarios. Furthermore, network packet loss rates, image quality assessments, end-to-end delays, and other link-related factors were introduced as constraints, to realize the real-time adjustment and optimization of the prediction model during the transmission process. Experimental results conducted on a semi-physical platform show that: the prediction performance of the proposed algorithm is better than the traditional prediction method, and the fitting degree of the prediction curve and the actual curve is more than 95.8%; compared with the single-layer prediction algorithm, the packet loss rate of the proposed algorithm in walking and driving scenarios decreases by 47.3% and 30.9%, respectively, and the quality of received video is improved by 12%.

RIS-IM System Based on Nonorthogonal Multiple Access



ZHUANG Ling, HUANG Kai

2023, 51(11):  28-34.  doi:10.12141/j.issn.1000-565X.230015

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Reconfigurable intelligent surface assisted index modulation (RIS-IM) scheme is a developed transmission technology in smart radio environment. However, the current relevant research only considers the direct transmission of M-ary modulation signal to a single user. It is necessary to use multiple access technology to make more users share time-frequency resources in the future scenario of wireless communication connecting massive users. Nonorthogonal multiple access (NOMA) technology uses power domain multiplexing of time-frequency blocks to connect more users and realizes efficient utilization of resources by actively introducing interference. Based on nonorthogonal multiple access, this paper proposed a reconfigurable intelligent surface assisted index modulation system (RIS-IM-NOMA) to realize multi-user access for RIS-IM. The system improves the quality of the received signal using the reconfigurable intelligent surface and at the same time selects the best transmitting antenna to transmit index information in this system. And time-frequency resources are allocated to more users through NOMA and the spectral efficiency is improved. The greedy detection method was used to detect the signal at the receiving end, and the upper bound of the bit error rate was derived and analyzed theoretically. Then an improvement scheme was proposed for the performance decline of bit error rate caused by interuser interference of NOMA. The spectral efficiency of the system was analyzed theoretically, and a power allocation method was proposed to solve the problem of fairness of spectral efficiency among users. The simulation results show that increasing the number of reflecting elements can effectively reduce the bit error rate of the system, and the proposed power allocation method can effectively ensure the fairness of the system. Thus, the effectiveness of the proposed schemes is verified.

Event-Triggered Impulsive Observer-Based Stabilization for Lipschitz Nonlinear Systems with Discrete-Time Stochastic Measurement Noises



LUO Shixian, CHEN Xin, HUANG Ganji

2023, 51(11):  35-43.  doi:10.12141/j.issn.1000-565X.230012

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In order to improve the utilization of computing or communication resources and reduce energy consumption, the study proposed the event-triggered impulsive observer-based output feedback control method for a class of nonlinear systems with aperiodic sampling and stochastic measurement noises. Firstly, by introducing an event-triggering mechanism that only depends on the discrete-time measurement output and an auxiliary variable, it designed a novel event-triggered impulsive observer. Then by constructing an augmented system composed of the original system and the observer error system and developing the quasi-periodic discretized Lyapunov function method, it established an ultimate bounded stability criterion in the mean square sense of the augmented closed-loop systems. The criterion reveals the influence mechanism of the sampling period, noise intensity, and event trigger parameters on system performance. Next, combined with the joint design approach, the output feedback controller synthesis problem was transformed into solving a set of LMIs based on the augmented system, thus solving the difficult problem that the state feedback gain and the observer gain cannot be separated in the presents of the stochastic measurement noise. Finally, on the Matlab platform, the performance of the proposed control method was analyzed via a connecting rod robotic arm. The experimental results demonstrate that the proposed method is effective in reducing the number of transmissions and conserving communication/computing resources. Furthermore, it successfully addresses the stabilization problems of nonlinear systems with stochastic measurement noise, thus confirming the effectiveness of the proposed approach.

Driverless Obstacle Avoidance and Tracking Control Based on Improved DDPG



LI Xinkai, HU Xiaocheng, MA Ping, et al.

2023, 51(11):  44-55.  doi:10.12141/j.issn.1000-565X.220747

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In the process of tracking and obstacle avoidance control of driverless vehicles, the controlled object has nonlinear characteristics and variable control parameters. The linear model and the fixed mathematical model of driverless vehicles are difficult to ensure the safety and stability of the vehicle in complex environments, and the driverless discrete control process increases the difficulty of control. To address such problems, in order to improve the accuracy of real-time control tracking trajectory of driverless vehicles, and at the same time reduce the difficulty of the whole control process, the paper proposed a Monte Carlo-depth deterministic policy gradient-based obstacle avoidance tracking control algorithm for driverless vehicles. The algorithm builds a control system model based on a deep reinforcement learning network, and adopts excellent training samples in the strategy learning sampling process. It optimizes the network training gradient with the Monte Carlo method, and makes a distinction between good and bad training samples for the algorithm. The excellent samples are used to find the optimal network parameters through a gradient algorithm, so as to enhance the learning ability of the network algorithm and realize a better and continuous control of the driverless vehicle. Simulation experiments of the control method were carried out in the computer simulation environment TORCS. The results show that the proposed improved DDPG algorithm can be applied to effectively achieve the obstacle avoidance tracking control of the driverless vehicle, and the tracking accuracy and obstacle avoidance effect of the unmanned car under its control is better than that of the deep Q network algorithm and the DDPG algorithm.

AGVS Path Planning Agorithm in Complex Environments



YAO Daojin, YIN Xiong, LUO Zhen, et al.

2023, 51(11):  56-62.  doi:10.12141/j.issn.1000-565X.230297

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In the field of warehousing and logistics, automatic guided truck system (AGVS) has the merits of high reliability and flexibility, but with the increase of the complexity of its working environment, the difficulty of path planning also increases. Aiming at the problem of low efficiency and easy conflict in AGVS path planning in complex environment, this paper proposed an improved AGVS path planning algorithm based on hierarchical distributed framework. Firstly, in order to improve the search efficiency of the algorithm in the path planning process, the evaluation function of the traditional A ^* algorithm was improved and fused with the bidirectional Floyd algorithm to increase the path smoothness, and the global optimal AGVS path is finally obtained. Secondly, the AGVS kinematics modeling was established, and the key nodes in the global optimal path were taken as temporary target points. By adjusting the initial poses of the robot and optimizing the evaluation function, the AGVS local path planning was completed appying the DWA algorithm to the temporary target points. Finally, AGVS collaborative planning strategy was introduced to achieve unified scheduling of inter-AGVS motion by assigning task priorities to AGVS, reducing the probability of conflicts between mobile machines, improving the robustness of AGVS path planning algorithm. Matlab simulation results show that the proposed improved algorithm can generate collision-free paths in both simple and complex environments. In complex environments, AGVS path length planned by the improved algorithm is shortened by 2.26% compared with that planned by the traditional A ^* algorithm. In the process of AGVS motion, the angular velocity and the linear velocity of the mobile robot are always maintained within -0.4~0.4 rad/s, and 0.6~1.2 m/s, which conforms to the kinematic characteristics of the mobile robot.

Materials Science & Technology

Effect of Particle Size on Hydration Kinetics and Microstructure Development of Recycled Brick Powder-Cement Pastes



YU Qijun, MA Ting, ZHANG Tongsheng, et al.

2023, 51(11):  63-73.  doi:10.12141/j.issn.1000-565X.220784

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With the advancement of urbanization and the transformation of the old city, the production and stock of construction waste in China are ever increasing, with waste clay bricks accounting for 50%~70%. It has been found that recycled brick powder has the potential as a supplementary cementitious material, but it can lead to a significant reduction in the mechanical properties of cement-based materials. In order to explore the effect of particle size on the activity of recycled brick powder and the hydration kinetics of cement, this study prepared recycled brick powder with different particle sizes by high-energy ball milling. The physical and chemical properties and hydration activity of recycled brick powder were characterized. The effect of particle size of recycled brick powder on the hydration process, microstructure and mechanical properties of recycled brick powder-silicate cement system was analyzed. Based on the Krstulovic-Dabic model, the hydration kinetic parameters of the system were obtained to realize the quantitative evaluation of the hydration process. The results show that with the decrease of the particle size of the recycled brick powder, the lattice distortion of the silicon-aluminum mineral becomes larger and the surface binding energy decreases, resulting in an increase in its hydration activity. The early hydration of recycled brick powder mainly plays a physical filling role, which can accelerate the early hydration of recycled brick powder-cement system and improve the hydration degree of crystallization nucleation and crystal growth→phase boundary reaction→diffusion process. With the decrease of particle size of recycled brick powder, the starting time of pozzolanic reaction is advanced and the degree of pozzolanic reaction is higher. Finally, the later strength of cement mixed with 30% fine-grained recycled brick powder exceeds that of pure cement. This paper lays a foundation for the efficient application of recycled brick powder in cement-based materials.

Effect of Pyrite Tailings Mineralizer on Calcination and Properties of Cement Clinker



YIN Suhong, LI Yanmei, DING Weimin, et al.

2023, 51(11):  74-81.  doi:10.12141/j.issn.1000-565X.230194

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The cement industry is a high energy consuming industry, and the use of mineralizers in the calcination process of cement clinker is an effective energy-saving method. Using solid waste as a mineralizer can also turn waste into treasure and achieve its resource utilization. With pyrite tailings as mineralizer, this study prepared Portland cement clinker with 0, 1.5%, 2.0% and 2.5% SO₃ at calcination temperature of 1 350 ℃, 1 400 ℃ and 1 450 ℃. Thermal analysis, X-ray diffraction (XRD), polarizing microscope, and other methods were used to analyze the effects of SO₃ addition on the calcination process, mineral composition, petrographic structure, and physical properties of the clinker. The results show that the best effect is achieved when the content of SO₃ is 2.0%. Under this proportion, the content of f-CaO in cement clinker decreases from 1.84% to 1.18%, which can significantly improve the burnability of raw meal. The addition of pyrite tailings can reduce the initial and peak temperatures of CaCO₃ decomposition in raw meal, and form two transition phases of calcium sulphosilicate (2C₂S·CaSO₄) and calcium sulphoaluminate (4CaO·3Al₂O₃·SO₃) at low temperature. This reduces the temperature of liquid phase by 35 ℃, promoting the formation and development of clinker minerals, and has a significant mineralization effect. The cement clinker obtained by calcination with pyrite tailings has good performance, and its compressive strength after curing for 3 days and 28 days is 33.1 and 61.8 MPa, respectively.

Estimation of P-S-N Curve of Metal Materials Based on Bayesian Neural Network



YANG Xufeng, LIU Zeqing, ZHANG Yi

2023, 51(11):  82-92.  doi:10.12141/j.issn.1000-565X.220649

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Fatigue failure is the main failure mode of mechanical structure, and the premise of the fatigue life prediction on mechanical structure is to obtain S-N curves of high precision based on test data. However, the fatigue test data often show large dispersion, so it is more appropriate to use probabilistic fatigue life curve (P-S-N) to describe the stress cycle relationship. To overcomes the limitations of the existing classical machine learning model which can only give the determined value of fatigue life but cannot quantify its dispersion in the analysis of material fatigue data, this study proposed a P-S-N curve estimation method for metal materials based on Bayesian neural network (BNN) model. Firstly, the weight parameters of the traditional neural network model were regarded as random variables, and the posterior distribution of the weight parameters was estimated by the BNN model according to the training samples. Then, considering that the existing posterior distribution estimation methods are easy to underestimate the uncertainty of weight parameters, this paper introduced a black-box alpha (BB-α) algorithm based on α divergence to estimate the posterior distribution of the weight parameters. Finally, the BNN model was used to analyze the fatigue data of 2524-T3 aluminum alloy, 2024-T4 aluminum alloy and S420MC steel. The results show that BNN can be used as an effective and robust model for fatigue data fitting and uncertainty quantification. Meanwhile, the BNN model based on BB-α algorithm can give a more accurate uncertainty quantification results of fatigue data.

Fluid Power & Mechatronic Control Engineering

Thickness Distribution of Low Stress Three-Layer Bearing for Cam Lobe Hydraulic Motor



LI Ying, WANG Bozhong, HE Shuang, et al.

2023, 51(11):  93-100.  doi:10.12141/j.issn.1000-565X.230413

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When the working speed of the low-speed high-torque cam lobe hydraulic motor is developing towards an extremely low speed (up to 0.2 r/min), one of its core friction pairs, the roller-piston pair, is difficult to establish a hydrodynamic lubricating oil film at low speeds, leading to wear fail of the friction pair. Therefore, a three-layer bearing bush structure of steel back-copper powder-self-lubricating material was usually arranged between the roller-piston pair to improve the lubrication ability of friction pair at low speed. However, the cam lobe motors usually need to withstand large loads, and how to design three-layer bearing with high bearing capacity has become a challenge in the design of cam lobe hydraulic motors. The thickness distribution of each layer of the three-layer bearing directly affects the maximum stress of the bearing under load, and then affects the bearing capacity and service life of the cam lobe hydraulic motor. In order to explore the effect of the thickness of each layer of the three-layer bearing bush on the overall bearing capacity of the bearing bush, this paper carried out the force analysis of the three-layer bearing bush, and obtained the mapping law between the thickness of the three-layer material and the maximum von Mises stress of the self-lubricating layer. And this paper also proposed a low-stress three-layer self-lubricating bearing bush thickness distribution scheme suitable for the roller-piston pair of cam lobe motors and designed a three-layer bearing thickness distribution scheme (the self-lubricating layer thickness was 0.2 mm, the copper powder layer thickness was 0.3 mm, and the steel back layer thickness was 1.0 mm) for an cam lobe hydraulic motor with a maximum working pressure of 31.5 MPa.The three-layer bearing using this scheme was installed on the hydraulic motor for motor performance testing. The test results show that the bearing capacity of the bearing under the thickness distribution can meet the requirements of the maximum working pressure of the cam lobe motor.

Study on Flow Distribution Mechanism of Low Speed High Torque Hydraulic Motor



YU Mingquan, ZHAO Jiyun, MAN Jiaxiang, et al.

2023, 51(11):  101-109.  doi:10.12141/j.issn.1000-565X.230406

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In applications such as coal mining, food and underwater operations, low speed high torque high water-based hydraulic motors have the advantages of high power-to-weight ratio and medium compatibility. However, the current high-water-based hydraulic motors still maintain the same flow distribution structure as oil motors and only replace the working medium with high-water-based emulsion instead of hydraulic oil. Traditional flow distribution disc structures use spring force to ensure sealing. Under low speed, high pressure, and high water-based conditions, the flow distribution disc wears heavily, resulting in serious leaks. For high-water-based emulsion drive systems, this paper proposed a valve flow distribution mechanism comprising valves, bearings, and a pentagon-wheel. The motor’s intaking and discharging process is controlled by a check valve, and the opening and closing of the valve is controlled by the pentagon-wheel. Then the paper carried out comparative analysis on flow distribution rules, advantages and disadvantages of eccentric-wheel, cam, and pentagon-wheel flow distribution mechanisms. It is found that the pentagon-wheel flow distribution structure can reduce the concentration of push rod stress and solve the phenomenon of push rod self-rotation jamming. Finally, the superiority of the five-star wheel flow distribution structure was verified by using AMESim. The prototype was prepared and the performance experiment was carried out. The results show that the pressure in the plunger cavity can be quickly established under different speed (10~90 r/min) and pressure (5~21 MPa). Compared with traditional disc flow distribution mechanisms, the leak rate of the valve flow distribution mechanism under high-water-based conditions of 21 MPa and 90 r/min is only 0.15 mL/min, significantly improving motor volume efficiency.

Study on 3D Flow Field Characteristics of Control Valve Based on 2D-PIV



LIU Xiumei, WU Su, LI Beibei, et al.

2023, 51(11):  110-118.  doi:10.12141/j.issn.1000-565X.230152

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The flow state in the flow channel of the control valve directly affects its service life and system stability. In order to explore the three-dimensional flow field information inside the control valve, a series of three-dimensional grid nodes were obtained by shooting different planes with a two-dimensional particle image velocimetry (2D-PIV) device, and the flow field information of unknown nodes was obtained by interpolation, so as to realize the three-dimensional reconstruction of the control valve flow field. The experimental results show that the overall trend of the three-dimensional reconstructed velocity field is consistent with that of the two-dimensional velocity field. The oil at the throttle port of the control valve forms a counter jet due to the throttling effect, and the jet converges to form a high-speed overall jet in the downstream of the valve core head. The combination of impinging jets on both sides in the top area of the valve core will produce a certain amount of oil backflow. The overall flow channel velocity decreases gradually with the moving out of the shooting plane. The velocity distribution of the upstream flow channel decreases steadily at first and then maintains a stable value. The velocity value near the throttle orifice increases first and then decreases, with a large variation. The wall resistance and shear force keep the near-wall velocity stable. The flow velocity in the downstream region is concentric and the flow field changes from turbulent flow to orderly flow. The simulation results show that the overall area of the three-dimensional reconstruction flow field is primarily consistent with the theoretical flow field. The maximum reconstruction error is 9.5%, occurring in the high-speed flow area of the throttle. The experimental reconstruction results is highly similar to the simulation reconstruction results and the reconstruction effect in the smooth flow area is better than that in the violent part. The research can provide a reference for the structural optimization design of the control valve and the improvement of cavitation performance, and is also provides an effective reference for the three-dimensional flow field measurement of the micro-channel.

Dynamic Load Distribution of Roller Thread Considering Gear Pair Meshing Excitation



XU Qianjin, MA Shangjun, NIU Maodong, et al.

2023, 51(11):  119-130.  doi:10.12141/j.issn.1000-565X.230296

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The synchronous meshing of threaded pairs and gear pairs is a typical feature of planetary roller screw transmission. To reveal the dynamic load fluctuation law of the screw pair caused by the meshing excitation of the gear pair and the inertia force generated by the roller rotating around the screw axis, this paper proposed a calculation method for the dynamic load distribution of the screw pair considering the inertia force and the meshing excitation of the gear pair. Firstly, based on the cylindrical collision theory, energy method, and time-varying spring model, the meshing excitation and time-varying meshing stiffness excitation of the gear pair were solved, respectively. Based on the spiral surface equation of the planetary roller screw, the static contact forces on the contact side of the roller screw and the roller nut were solved. Then, the force analysis was conducted on the roller, and the dynamic load distribution law of the screw pair considering the meshing excitation of the gear pair was obtained based on the deformation coordination condition of the screw pair and compared with the calculation results of the dynamic contact finite element model of the screw pair, so as to verify the correctness of the theoretical model. Finally, the paper analyzed the impact of inertia force and gear pair meshing excitation on the dynamic contact force and dynamic load distribution of threaded pairs. The results shows that: inertia force leads to a greater dynamic contact force on the roller nut side than on the roller screw side; when considering the meshing excitation of the gear pair, the contact force on the roller screw side decreases with the increase of the number of threads, while the contact force on the roller nut side increases with the increase of the number of threads; the meshing excitation of the gear pair causes the contact force between the roller screw and the roller nut side thread to fluctuate in the same pattern over time.

Fatigue Analysis and Life Prediction of Recirculating Planetary Roller Screw Mechanism



QIAO Guan, LIAO Rong, ZHANG Xiaomin, et al.

2023, 51(11):  131-139.  doi:10.12141/j.issn.1000-565X.230146

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The recirculating planetary roller screw mechanism, as a derivative of planetary roller screw mechanism, is a transmission mechanism that is engaged by the screw or nut thread and multiple circular groove rollers. To study the random vibration fatigue characteristics of the recirculating planetary roller screw mechanism, this paper established a finite element model of the mechanism based on fatigue failure theory, and conducted the dynamic analysis and fatigue life prediction. Firstly, according to the material stress-number of cycles (S-N) curve and Miner’s linear damage accumulation theory, fatigue analysis was carried out on the recirculating planetary roller screw mechanism using the related software, and fatigue results in the contact area and damage values at each node were obtained. Then, based on the developed four fatigue life prediction models, the obtained analytical solutions were compared with the simulated damage values. The results show that the resonance induced by the recirculating planetary roller screw mechanism at 3 960 Hz causes the most damage to the mechanism. When the excitation frequency is the same, the area of maximum contact stress and minimum fatigue life is the same. Besides, the corresponding frequencies of the peak stress in the harmonic response analysis and that of the peak power spectral density in the fatigue analysis of the recirculating planetary roller screw mechanism are the same. This study can provide a theoretical guidance for the design and fatigue optimization of the recirculating planetary roller screw mechanism.

Analysis of Forming Characteristics of Conductive Slip Ring Brush Wire by Finite Element Method



LI Junye, TIAN Gongqiang, WANG Xinpeng, et al.

2023, 51(11):  140-150.  doi:10.12141/j.issn.1000-565X.230410

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The performance of the conductive slip ring brush wires has a vital impact on the lifespan of the satellite in orbit and the overall energy safety. In order to ensure the real-time transmission of signal and current, the brush wire angle needs to be controlled. This study established a three-dimensional model of the brush plate and the brush wire based on the theoretical analysis of the finite element method. The best way for producing the brush wire’s angles was identified by combining the explicit dynamics and implicit statics finite element simulation techniques. The brush wire angle forming and rebound were then fully simulated with these techniques. This paper presented a measurement method based on the rebound process of the brush wire angle, and compared the simulation value with the theoretical value of the brush wire rebound angle. The findings demonstrate that compared to the single-sided deflector plate and the double-sided short clamping plate, the double-sided long clamping plate performs at its finest when forming the brush wire’s angle; the brush wire’s rebound angle is positively correlated to the forming angle; the larger the forming angle of the brush wire, the larger the rebound deformation value of the brush wire after forming; when the brush wire is formed at an angle of 120° or more, the brush wire material is likely to be damaged due to excessive residual stresses. In order to prevent the destruction of the left root of the brush wire during elastic-plastic deformation, the left clamping surface of the clamping plate should be placed as close as possible to the left root of the brush wire to increase the constraints on the root of the brush wire, so as to ensure the quality of the angle forming of the brush wire; the maximum relative error in the angle of rebound of the brush wire is about 2°, but the average rebound inaccuracy is about 1°; the overall rebound trend is generally consistent, so the proposed method can well indicate the variation law of the rebound angle of the brush wire.