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Optimization of PID Control Parameters for Quarter-Vehicle Model Active Suspension System Using Back Propagation Neural Network and Genetic Algorithm Methods 6th

Optimization of PID Control Parameters for Quarter-Vehicle M...

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6th International Conference on mechanical engineering, ICOME 2023

作者： Effendi, M.K. Pande, D.M.R. Harnany, D. Hendrowati, W. Department of Mechanical Engineering Faculty of Industrial Technology and Systems Engineering Institut Teknologi Sepuluh Nopember Surabaya Indonesia

ISBN: (纸本)9789819778973

A suspension system is designed to attenuate vibrations and enhance passengers’ comfort levels when a vehicle traverses uneven road contours. With additional power to control the actuators’ force, the active suspension system produces better ride quality than passive suspension systems. System modeling will be carried out using a quarter-vehicle model with a disturbance input form of a step input of 0.1 m. In this study, the control system used is the PID controller, with the parameters of the controller being tuned using the Back Propagation Neural Network-Genetic Algorithm (BPNN-GA) metaheuristic method employing MATLAB R2022b software. In this method, BPNN is used to produce a network that represents the correlation between controller parameters (i.e., Kp, Ki, and Kd) and system response (i.e., Integral Times Absolute Error (ITAE)). The ITAE value represents the value of Settling Time (Ts) and Peak Overshoot (PO) in a damping system. Next, the Genetic Algorithm (GA) is employed to determine the best BPNN's network with a minimum MSE (Mean Squared Error) value. The performance of BPNN-GA is then compared with Ziegler Nichols method. The best BPNN’s network is obtained with five hidden layers, ten nodes in each hidden layer, and the satlin activation function achieving an MSE training value of 1.6477 × 10–8. The most optimum Kp, Ki, and Kd values are identified through the BPNN-GA method, namely 809193, 621978, and 243984, with a settling time (TS) value of 1.33 s and a peak overshoot of −0.00834 m, along with a Root Mean Square (RMS) value of 0.5747 m/s2. Moreover, in accordance with the ISO 2631 standard, the active suspension system model is classified as slightly uncomfortable. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： MATLAB

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Thermal-hydraulic performance of turbulent flows across a heated round tube installed through several perforated twisted tapes

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International Journal of Numerical Methods for Heat and Fluid Flow 2024年第5期34卷 1995-2021页

作者： Perng, Shiang-Wuu Wu, Horng Wen Huang, De-An Department of Mechanical Engineering Kun Shan University Tainan Taiwan Department of Systems and Naval Mechatronic Engineering National Cheng Kung University Tainan Taiwan

Purpose: The purpose of this study is to advance turbulent thermal convection inside the constant heat-flux round tube inserted by multiple perforated twisted tapes. Design/methodology/approach: The novel design of this study is accomplished by inserting several twisted tapes and drilling some circular perforations near the tape edge (C1, C3, C5: solid tapes;C2, C4, C6: perforated tapes). The turbulence flow appearances and thermal convective features are examined for various Reynolds numbers (8,000–14,000) using the renormalization group (RNG) (Formula presented.) turbulent model and Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm. Findings: The simulated outcomes reveal that inserting more perforated-twisted tapes into the heated round tube promotes turbulent thermal convection effectively. A swirling flow caused by the twisted tapes to produce the secondary flow jets between two reverse-spin tapes can combine with the main flow passing through the perforations at the outer edge to enhance the vortex flow. The primary factors are the quantity of twisted tapes and with/without perforations, as the perforation ratio remains at 2.5 in this numerical work. Weighing friction along the tube, C6 (four reverse-spin perforated-twisted tapes) brings the uppermost thermal-hydraulic performance of 1.23 under Re = 8,000. Research limitations/implications: The constant thermo-hydraulic attributes of liquid water and the steady Newtonian fluid are research limitations for this simulated work. Practical implications: The simulated outcomes will avail the inner-pipe design of a heat exchanger inserted by multiple perforated twisted tapes to enhance superior heat transfer. Originality/value: These twisted tapes form tiny circular perforations along the tape edge to introduce the fluid flow through these bores and combine with the secondary flow induced between two reverse-spin tapes. This scheme enhances the swirling flow, turbulence intensity and fluid mixing

关键词： Reynolds number

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Power optimization of photovoltaic modules under varying environmental conditions based on current equalization collaborating with constant voltage control

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Clean Energy 2024年第4期8卷 169-182页

作者： DaiBin Tang Fei Lu Siaw Tzer Hwai Gilbert Thio School of Electrical Engineering Anhui Technical College of Mechanical and Electrical EngineeringWuhu 241002China Centre for Sustainability in Advanced Electrical and Electronics Systems(CSAEES) Faculty of EngineeringBuilt Environment and Information TechnologySEGi University47810 Petaling JayaSelangorMalaysia

The performance of photovoltaic(PV)modules is affected by environmental factors such as irradiance and temperature,which can lead to a decrease in output performance or even *** study proposes an improved formula for calculating the real maximum power of PV modules by analysing the influence of irradiance and temperature.A simulation model is developed using PLECS software to simulate the global maximum power of PV modules under different environmental conditions and the results are compared with the calculated real maximum power.A power optimization scheme for PV modules is then proposed based on current equalization and constant voltage *** scheme employs a single-switch multi-winding forward-flyback converter to equalize the mismatched currents between cell strings,thereby enhancing the output *** proportional-integral controllers are utilized to achieve constant voltage control and obtain the real maximum power of PV *** models are built in the PLECS simulation platform to evaluate the performance of a global maximum power point tracking scheme based on the traditional perturb-and-observe(TPO)algorithm with current equalization,a segment perturb-and-observe algorithm without current equalization,and the proposed power optimization *** simulation results demonstrate that the proposed constant voltage control has greater efficiency than the TPO *** proposed scheme achieves a significant improvement in efficiency,with a 27.87%increase compared with the segment perturb-and-observe algorithm without current equalization.

关键词： current equalization constant voltage control forward-flyback converter PV modules perturb-and-observe(P&O)algorithm

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Configuration Design and Size Optimization of a High-Precision Novel Parallel Pointing Mechanism Based on Interference Separation

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Chinese Journal of mechanical engineering 2024年第5期37卷 365-386页

作者： Sen Wang Shihua Li Xueyan Han Jiahao Wei Xueyuan Gao Hongyu Xu Hebei Provincial Key Laboratory of Parallel Robot and Mechatronic Systems Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

Pointing mechanism is widely used in aerospace field,and its pointing accuracy and stability have high *** pointing mechanism will be affected by external interference when it *** order to eliminate the impact of interference forces on the output accuracy of the mechanism,firstly,this paper proposes a design method for highprecision pointing mechanisms based on interference separation,aiming at the high-precision pointing requirements of pointing *** on the screw theory,a synthesis method for inner compensation mechanisms has been *** a new type of double-layer parallel mechanism has been designed to compensate for interference ***,the kinematics and dynamics of the mechanism are carried *** evaluation index for compensating external interference forces is *** interference compensation analysis is conducted for the pointing *** correctness of the proposed interference force compensation coefficient is ***,in order to find the optimal solution for the workspace and interference force compensation coefficient of the pointing mechanism,multi-objective optimization design of the structural parameters of the mechanism was carried out based on the particle swarm optimization *** provides a theoretical basis for the prototype design of the subsequent double-layer parallel *** double-layer parallel mechanism combines the advantages of large load-bearing capacity,large workspace,and high output *** can be better applied in the aerospace field where high-precision pointing and force interference compensation are integrated.

关键词： Pointing mechanism Interference separation Double-layer parallel mechanism Force compensation coefficient Multi-objective optimization

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Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan ZHAO Han YAN Ge YAN Ao CHEN Wenming ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

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Process planning and contour-based error compensation for precision grinding of miniature scalpels

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先进制造进展（英文版） 2024年第1期12卷 108-123页

作者： Cheng Fan Cao-Yang Xue Jun Zhao Wei Jiang Wen-Ge Han Lei Zhang Li-Ning Sun Jiangsu Provincial Key Laboratory of Advanced Robotics School of Mechanical and Electrical EngineeringSoochow UniversitySuzhou 215021JiangsuPeople's Republic of China Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical and Electrical EngineeringZhejiang UniversityHangzhou 310027People's Republic of China State Key Laboratory of Intelligent Equipment and Manufacturing School of Mechanical EngineeringZhejiang University of TechnologyHangzhou 310023People's Republic of China

Miniature scalpels are mainly used in microsur-geries such as ophthalmic and cardiovascular *** size of a miniature scalpel is only a few millimeters,and the precision of the blade shape is high,which makes pro-duction of miniature scalpels extremely *** study proposes a new sharpening process for grinding miniature scalpels on a four-axis machine tool.A post-processing algo-rithm for a four-axis grinding machine based on a kinemat-ics model is *** then propose a corresponding parameter calibration method for the parameters used in the kinematics *** of possible errors in the param-eter calibration,a contour-based error compensation method is proposed for accurate adjustments to the edge shape fol-lowing *** can solve the problem of large devia-tions between the actual edge shape after grinding and the ideal edge *** effectiveness of the proposed process planning and error compensation method is verified experi-mentally,and the grinding process parameters of the minia-ture scalpel are optimized to improve its surface processing *** sharpness of the optimized miniature scalpel is less than 0.75 N,and the blade shape is symmetrical,which meets the technical requirements of miniature scalpels.

关键词： Miniature scalpel Sharpening Kinematics Error compensation Grinding

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Vertically Aligned Carbon Nanotube (VACNT)/PDMS Composite with Changeable Lateral Stiffness

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Journal of Biorheology 2024年第2期38卷 103-111页

作者： Putra, Alfi Eko Miyoshi, Hiromi Yang, Ming Department of Mechanical Systems Engineering Tokyo Metropolitan University 6-6 Asahigaoka Hino-shi Tokyo191-0065 Japan

Lateral stiffness and topography of culture substrate are critical parameters for controlling stem cell differentiation. However, controlling the lateral stiffness of the VACNT bundle tip, that is included in pillar category, is remained to be solved in a range of cell culture. In this study, we transferred the 18 μm VACNT length into PDMS matrix to control VACNT lateral stiffness with a partial immersion method. VACNT/PDMS composite was synthesized in which 5–10 μm of VACNT length at top surface was maintained free to move. The Lateral force measurement (LFM) demonstrated that VACNT/PDMS composite bundle tip with 6 μm PDMS was the stiffest, followed by raw VACNT and VACNT with 8.6 μm PDMS. The lateral stiffness values of the three VACNT condition were 1.037 N/m, 0.914 N/m, and 0.535 N/m, respectively. These values at certain thickness of PDMS could take a role as reinforcement or declination for VACNTs tips stiffness. We suggest that the VACNT have potential to control stem cell differentiation due to their sophisticate change of lateral stiffness. © Japanese Society of Biorheology 2024.

关键词： Stem cells

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Determination of multiaxial stress rupture criteria for creeping materials:A critical analysis of different approaches

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Journal of Materials Science & Technology 2023年第6期137卷 14-25页

作者： Kun Zhang Jian-Ping Tan Wei Sun Kamran Nikbin Shan-Tung Tu Key Laboratory of Pressure Systems and Safety(Ministry of Education) School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai200237China Department of Mechanical Materials and Manufacturing EngineeringUniversity of NottinghamNottinghamNG72RDUK Department of Mechanical Engineering Imperial College LondonLondonSW72AZUK

Materials in engineering applications are rarely *** reality,failures under multiaxial loading has been widely observed in engineering *** life prediction of a component under multiaxial stresses has long been a challenging issue,particularly for high temperature *** distinguish the mode of failure ranging from a maximum principal stress intergranular damage to von Mises effective stress rupture mode a multiaxial stress rupture criterion(MSRC)was originally proposed by Sdobyrev and then Hayhurst and Leckie(SHL MSRC).A multiaxial-factor,α,was developed as a result which was intended to be a material constant and differentiates the bias of the MSRC between maxi-mum principal stress and effective *** success of the SHL MSRC relies on accurately calibrating the value ofαto quantify the multiaxial response of the material/geometry *** find a more suitable approach for determining MSRC,the applicability of different methods are *** that the resulting analysis of the various approaches can be affected by the creep failure mechanism,princi-ples in the determination of MSRC with and without using continuum damage mechanics approaches are *** viability of uniaxial material parameters in correlating withαthrough the analysis of available data in literature is also *** is found that the increase of the uniaxial creep dam-age tolerance parameterλis accompanied bythe decreaseof theα-value,whichimplies thatthe creep ductility plays an important role in affecting the multiaxial rupture behavior of materials.

关键词： Multiaxial stress rupture criterion Creep failure mechanism Uniaxial parameter Creep damage tolerance parameter Continuum damage mechanics

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Learning-based MPC for Autonomous Motion Planning at Freeway Off-ramp Diverging

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年 1-11页

作者： Qi, Xudong Zhang, Libin Wang, Ping Yang, Jingwen Zou, Tao Liu, Wanquan School of Electronics and Control Engineering Chang'an University Xian Shaanxi China School of Intelligent Systems Engineering Sun Yat-Sen University Guangzhou Guangdong China School of Mechanical and Electrical Engineering Guangzhou University Guangzhou China

Off-ramp diverging road segment is the preparation area for vehicles driving away from the freeway, while it causes more traffic conflicts making it a typical safety bottleneck. Focusing on improving driving safety, a Learning-based Model Predictive Control (LMPC) strategy is proposed to deal with the motion planning of autonomous vehicles (AVs) considering the dynamic driving behavior of surrounding traffic occupants in this area. The traditional MPC is combined with the reinforcement learning (RL) method to impose constraints for limitations to ensure safety while reducing conservatism. The Q-network of RL is used to build a terminal cost function to dynamically adjust the scale of the prediction horizon, which improves the speed of convergence while maintaining exploration of LMPC. Experimental testing scenarios are setup with considering different driving behaviors of surrounding vehicles to validate the performance of the proposed approach. The simulation results show that the LMPC can stably and flexibly plan the motion behavior of AVs, achieving a planning accuracy of 99.31%, which has the potential for practical application. IEEE

关键词： Model predictive control

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Design and optimization of CSP power plants for Pakistan:a comparative study

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Clean Energy 2023年第3期7卷 690-704页

作者： Kashif Liaqat Juan C.Ordonez Department of Mechanical Engineering FAMU-FSU College of EngineeringEnergy and Sustainability Centerand Center for Advanced Power SystemsFlorida State UniversityTallahasseeFL 32310USA

Despite having very high solar irradiance,Pakistan still does not have any installed concentrated solar power(CSP)*** studies have shown that multiple locations within the country are suitable for CSP plants,but there is limited availability of comprehensive comparative ***,this article presents a comparative analysis of different CSP technologies in Pakistan,focusing on their potential to address the country’s energy *** study evaluates the pros and cons of different CSP technologies at various locations through site assessment,modelling,optimization and economic analysis using the System Advisor *** and Nawabshah were selected as the locations for modelling multiple scenarios of 100-MW plants,using central receiver systems,parabolic trough collectors and linear Fresnel *** plants were integrated with thermal energy storage and the storage capacity was optimized using parametric *** results showed that a central receiver system for the location of Quetta was the most favourable option,with an annual energy yield of 622 GWh at 7.44 cents/kWh,followed by a central receiver system for Nawabshah(608 GWh,9.03 cents/kWh).This study is the first to show that switching between line-concentrated and point-concentrated CSP technologies can open new opportunities for sites in Pakistan with relatively high solar resources,resulting in a 21.3%reduction in the levelized cost.

关键词： concentrated solar power parabolic trough collector linear Fresnel reflector central receiver System Advisor Model Pakistan

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