Meccanica最新文献

{"title":"Optimal design of a novel tuned mass rate-independent damper for structural vibration suppression","authors":"Junqi Jiang,&nbsp;Shun Weng,&nbsp;Hao Luo,&nbsp;Hongping Zhu","doi":"10.1007/s11012-025-01980-w","DOIUrl":"10.1007/s11012-025-01980-w","url":null,"abstract":"<div><p>In the present study, a novel type of nontraditional tuned mass damper (TMD), termed as a tuned mass rate-independent damper (TMRD), was proposed for structural vibration suppression. The proposed TMRD consisted of a spring element, a mass element, and a rate-independent linear damping (RILD) element, which generated damping forces independent of the excitation frequencies. Based on the fixed-point theory, analytical formula of optimally designing the characteristic parameters of the TMRD were derived. The advantages of the TMRD over TMDs in suppressing the structural vibration and damper stroke were demonstrated, when they were separately used in flexible structures subjected to harmonic and earthquake-induced ground motions. For practical applications, an approximate method was presented to passively realize the proposed TMRD. It was suggested that the proposed method can be used to physically realize the TMRD and provide a superior solution than the conventional TMD to suppressing the structural vibration and damper stroke.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"1099 - 1114"},"PeriodicalIF":1.9,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the stiffness of spur gear pairs based on the improved energy method under multiple influencing factors","authors":"Fei Hu,&nbsp;Biao Luo,&nbsp;Fu-hua He,&nbsp;Qiao Yang","doi":"10.1007/s11012-025-01979-3","DOIUrl":"10.1007/s11012-025-01979-3","url":null,"abstract":"<div><p>To investigate the effects of axial misalignment, lead crown relief, and temperature on the meshing stiffness of gears, this study aims to derive high-precision gear stiffness values that are more aligned with practical engineering applications. Based on the thermal expansion theory, slice coupling effect, and involute profile theory, a thermal stiffness model for meshing spur gear pairs under multiple influencing factors has been established, integrating the improved potential energy method and the nonlinear contact stiffness calculation approach. A calculation method for the thermal stiffness of meshing spur gear pairs, considering the impacts of axial misalignment and lead crown relief, has been developed. Furthermore, the mechanisms by which varying temperature, modification amounts, and misalignment affect the meshing stiffness of spur gear pairs have been explored. The results indicate that both lead crown relief and axial misalignment alter the load distribution across the tooth width, leading to a relative load concentration and consequently affecting the deformation of the gears under external loading, thereby influencing their meshing stiffness. It was found that the meshing stiffness decreases with an increase in axial misalignment and lead crown relief amounts. Additionally, with the introduction of temperature effects, an increase in temperature further reduces the meshing stiffness of the gear pair. The thermal deformation induced by temperature variations results in profile errors, affecting the actual meshing positions of the gears and altering the dimensions of single and double tooth intervals along the meshing line. This research establishes a theoretical foundation for the design of gear systems and the study of gear transmission system dynamics.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"1079 - 1097"},"PeriodicalIF":1.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spur gear teeth profile optimization through tensor-based kinematics: integrating the Reuleaux method with differential evolution","authors":"Michał Batsch","doi":"10.1007/s11012-025-01970-y","DOIUrl":"10.1007/s11012-025-01970-y","url":null,"abstract":"<div><p>This paper presents a novel method for spur gear tooth profile optimization, addressing the challenge of designing gears with improved performance. Traditional gear designs often compromise between contact stress, wear, and noise. This research explores a wider design space to identify gear profiles offering a better balance. The proposed approach leverages tensor-based kinematics combined with the Reuleaux method for conjugate profile generation, creating a robust framework for exploring potential designs. This framework defines an objective function considering multiple performance criteria. Differential evolution is employed to search for novel tooth profiles minimizing this function. The performance of optimized profiles is compared against existing designs, including involute, S-gears, and cosine gears. Key performance indicators include Hertz contact and subsurface shear stresses, normal force, sliding factor, specific sliding, contact ratio, and gear mesh stiffness. Results demonstrate the method’s effectiveness in generating improved tooth profiles. Optimized solutions exhibited contact and shear stress reductions comparable to 30-degree involute and S-gears, suggesting improved pitting resistance and wear. Some designs showed substantial specific sliding reductions, indicating the potential for reduced heat generation and surface wear. While cosine gears showed reduced contact stress, they also exhibited lower contact ratios, potentially increasing dynamic loads. These optimized solutions offer a promising path towards designing high-performance gears tailored to specific applications. The method effectively explores the vast solution space and generates tooth profiles fulfilling desired optimization trade-offs, paving the way for future research incorporating additional performance criteria and exploring more complex gear geometries.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"1053 - 1077"},"PeriodicalIF":1.9,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of a flutter-excited articulated ichthyoid propulsor","authors":"Tomasz Szmidt","doi":"10.1007/s11012-025-01974-8","DOIUrl":"10.1007/s11012-025-01974-8","url":null,"abstract":"<div><p>A concept of an ichthyoid propulsor mimicking the undulating motion of a swimming fish is proposed and verified. The propulsor consists of an articulated fluid-conveying pipe with a triangular fin attached to its free end. A sufficiently high flow velocity in the propulsor leads to the instability of the system and the possible appearance of snake-like flutter vibrations. A dynamical model of the system is proposed. It is based on classical Benjamin’s model of the dynamics of an articulated fluid-conveying pipe and Lighthill’s elongated body theory, which quantifies hydrodynamic forces generated by the swimming fish. Parameters of the system for which the propulsor is subject to dynamic loss of stability, leading to the appearance of periodic flutter vibrations, are identified. Methods of bifurcation analysis, supported by numerical simulations, prove that the system can undergo a supercritical Hopf bifurcation. This soft self-excitation yields a stable limit cycle of the system, for which the thrust and lateral forces generated by the propulsor are calculated. It is shown that the mean value of the thrust is positive for a range of swimming speeds. The performance of the propulsor is assessed in relation to the swimming speed. The research may broaden knowledge about articulated pipes conveying fluid and support possible applications of the proposed propulsor.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"1035 - 1052"},"PeriodicalIF":1.9,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Workspace analysis of parallel mechanisms by considering active joints ranges of motion using a method based on interval analysis","authors":"Fatemeh Pourkariman,&nbsp;Mehdi Karimi,&nbsp;Payam Varshovi-Jaghargh,&nbsp;Mehdi Tale Masouleh","doi":"10.1007/s11012-024-01892-1","DOIUrl":"10.1007/s11012-024-01892-1","url":null,"abstract":"<div><p>The parallel robots workspace plays an important role in their design and construction. In this paper, a new algorithm is presented based on the concepts of interval analysis to determine the parallel robots workspace by considering joints ranges of motion. The proposed algorithm is based on the kinematics equations, interval arithmetic computations and refinement method. In this algorithm, the system of interval nonlinear equations obtained from kinematic analysis is solved simultaneously and the refinement operation is carried out to accurately calculate the intervals of the equations. A type of refinement operation, namely the slope form, is used in this method to eliminate the excess width of intervals of equations. The proposed algorithm is implemented on 3 and 4-DOF Delta parallel robots of Human and Robot Interaction Laboratory of Tehran university. The workspace of 3-DOF Delta parallel robot and the constant-orientation workspace of 4-DOF Delta parallel obtained from the proposed method for the different active joints ranges of motion are compared with the results of the method based on interval analysis without refinement operation and the geometric method. The results show that the proposed algorithm calculates the parallel robot workspace with appropriate accuracy.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"1015 - 1034"},"PeriodicalIF":1.9,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Static and dynamic performance of porous Ti6Al4V tibia implant designs based on triply periodic minimal surface scaffolds","authors":"Basma Eltlhawy,&nbsp;Noha Fouda,&nbsp;Ibrahim Eldesouky","doi":"10.1007/s11012-025-01967-7","DOIUrl":"10.1007/s11012-025-01967-7","url":null,"abstract":"<div><p>The current study aims to analyze the load transfer between bone and three different TPMS-stem implants designed for tibia-total knee replacement (TKR) application through an initial stage of recovery and after healing time under static and dynamic loading conditions. The TPMS-based scaffolds, Schwarz, diamond, and gyroid, are used for tibia-stem designs. The mechanical performance of TPMS-stem implants was investigated based on von Mises stress for various loading conditions using ANSYS 2021R1. The results showed that TPMS-stem implants increase the maximum von Mises stress on the bone surface under the tibia tray by 14–24% under static loading and 15–36% under dynamic loading compared to solid-stem implants. Also, TPMS-stem implants reduced the maximum von Mises stress in the stem tip area when static and dynamic loading were considered. Stress reductions of 21.3, 21, and 17% were obtained under static loading for diamond, Schwarz, and gyroid stem implants, respectively.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"999 - 1014"},"PeriodicalIF":1.9,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of spur gear pairs considering meshing impacts based on energy methods","authors":"Lingyun Zhu,&nbsp;Yanfa Guan,&nbsp;Xiangfeng Gou","doi":"10.1007/s11012-025-01963-x","DOIUrl":"10.1007/s11012-025-01963-x","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The value of meshing impact is highly recognized due to its effect on vibration and noise in mechanical systems. Meshing impacts were investigated in the past using the impulse method characterized by smaller impact forces and longer impact times. They are calculated using the energy method in the paper to demonstrate that the impact force is over eight times greater than that method, while impact time is reduced to approximately one-sixth of that method. An improved model of meshing impact has been developed based on the kinetic energy theorem and Hertzian contact theory to enhance the accuracy of the results. An improved nonlinear dynamics model of spur gear pairs has been developed based on meshing impacts. The &lt;i&gt;i&lt;/i&gt;th tooth pair from meshing-in to meshing-out will experience meshing-in impact (MII) → double tooth-pair meshing zone (DTMZ) → double-to-single switching impact (DSSI) → single tooth-pair meshing zone (STMZ) → single-to-double switching impact (SDSI) → DTMZ → meshing-out impact (MOI). Boundary impacts are observed when the gear teeth arrive at the boundary from disengagement, including driving-tooth-side boundary impact (DBI) and backing-tooth-side boundary impact (BBI). The dynamics of the system both with and without the meshing effects are investigated using bifurcation diagrams, top Lyapunov exponent (TLE) diagrams, Poincaré maps, phase portraits, and force–time diagrams. The results indicate that larger force mutations lead to more pronounced impact phenomena and greater changes in displacement and velocity. This research lays the groundwork for future investigations into the meshing impacts of other gears. @@ The &lt;i&gt;i&lt;/i&gt;th teeth from meshing-in to meshing-out will experience meshing-in impact &lt;span&gt;((t_{{{text{Mi}}}}^{i} to t_{{{text{Mi1}}}}^{i} ))&lt;/span&gt; → double tooth-pair meshing zone &lt;span&gt;((t_{{{text{Mi1}}}}^{i} to t_{{text{A}}}^{i} ))&lt;/span&gt; → double-to-single switching impact &lt;span&gt;((t_{{text{A}}}^{i} to t_{{{text{A1}}}}^{i} ))&lt;/span&gt; → single tooth-pair meshing zone &lt;span&gt;((t_{{{text{A1}}}}^{i} to t_{{text{C}}}^{i} ))&lt;/span&gt; → single-to-double switching impact &lt;span&gt;((t_{{text{C}}}^{i} to t_{{{text{C1}}}}^{i} ))&lt;/span&gt; → double tooth-pair meshing zone &lt;span&gt;((t_{{{text{C1}}}}^{i} to t_{{{text{Mo}}}}^{i} ))&lt;/span&gt; → meshing-out impact &lt;span&gt;((t_{{{text{Mo}}}}^{i} to t_{{{text{Mo1}}}}^{i} ))&lt;/span&gt; according to the multi-state meshing and meshing impacts of the spur gear pair. Boundary impacts are observed when a tooth reaches the boundary from disengagement, including driving-tooth-side boundary impact and backing-tooth-side boundary impact. An improved model of meshing impact has been established based on the kinetic energy theorem and Hertzian contact theory. An improved nonlinear dynamics model of spur gear pair is developed based on the multi-state meshing and meshing impacts. The dynamics of the system considering meshing impacts and without meshing impacts are investigated using bifurcation diagrams, ","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"973 - 997"},"PeriodicalIF":1.9,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Special issue: analysis and design of shell and spatial structures","authors":"Sigrid Adriaenssens,&nbsp;Amedeo Manuello Bertetto,&nbsp;Francesco Marmo","doi":"10.1007/s11012-025-01975-7","DOIUrl":"10.1007/s11012-025-01975-7","url":null,"abstract":"","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 3","pages":"497 - 498"},"PeriodicalIF":1.9,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic analysis and driving parameters study of bidirectional solar array system with multiple clearance joints","authors":"Yingyong Shen,&nbsp;Cong Wang,&nbsp;Yuntao Hua,&nbsp;Shiyu Tan,&nbsp;Qiuyao Zheng,&nbsp;Jingbo Gao","doi":"10.1007/s11012-025-01965-9","DOIUrl":"10.1007/s11012-025-01965-9","url":null,"abstract":"<div><p>Torsion springs are commonly used as drive devices in spacecraft solar array systems. In this study, a multibody dynamic model of a spatial bidirectional solar array with multiple clearance joints is established to investigate the dynamic characteristics of a variable topology solar array system. A multistage solving strategy is proposed to ensure the multiple deployment processes of the system. The influences of the driving parameters on the dynamic behaviours, collision characteristics and spacecraft attitude of the system are thoroughly revealed. The effects of clearances on the vibration and stability of the solar array are also analysed. Latch time, peak angular velocity and stabilization period are proposed as key metrics to analyse the system dynamic characteristics. The results demonstrate that increasing the driving parameters reduces the latch times and increases peak angular velocities. Based on the stabilization period trends, the driving parameters are classified into stable and unstable regions. In stable regions, larger driving parameters accelerate vibration attenuation and reduces the nonlinearity and chaos of the system, thus facilitating quicker suppression of the contact forces. Moreover, clearances exacerbate angular velocity oscillations and lead to faster vibration attenuations of the solar panels. For the spacecraft attitude, larger driving parameters induce earlier shifts in the roll and pitch channels and significantly increase the yaw angle.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"953 - 972"},"PeriodicalIF":1.9,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frequency response characteristics of the stereocilia tip-link tension in different regions of the cochlea","authors":"Jiakun Wang,&nbsp;Junyi Liang,&nbsp;Bin Liu,&nbsp;Wenjuan Yao","doi":"10.1007/s11012-024-01930-y","DOIUrl":"10.1007/s11012-024-01930-y","url":null,"abstract":"<div><p>Research on the mechanism of sound perception in the cochlea has always been an important challenge for scientists of humans. Therefore, the frequency response of stereocilia in the cochlear different regions and the changes in tip link tension was researched, which may deepen the understanding of the physiological role of stereocilia in relation to their biomechanical behaviours and the frequency encoding mechanism in the auditory system. In this paper, the stereocilia motion is described as a forced vibration structure, and the effect of the lymphatic fluid in the cochlea on the stereocilia is considered, and a stereocilia motion model is established. The tension distribution of the tip link at different frequencies was solved. The correctness of the model was proved by comparing the response frequencies of the tip links at different positions with the Greenwood frequency. An increase in the elastic modulus of stereocilia leads to a non-linear decrease in the tension of the tip link, while an increase in the elastic modulus of the tip link leads to an increase in the tension of the tip link. Reducing the proportion of low and medium stereocilia to high stereocilia helps to improve low frequency resolution. In addition, the height gradient of stereocilia has a significant impact on their frequency response characteristics, and there are significant differences in the resolution and response range of stereocilia in different rows of outer hair cells. There are significant differences in the frequency resolution capability and response range of stereocilia of outer hair cells in different rows.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"60 4","pages":"911 - 925"},"PeriodicalIF":1.9,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}