Pub Date : 2024-07-31DOI: 10.1177/09544062241266325
Huaixin Lin, Gang Jin, Shaokun Luo, Guangyu Wang, Zhanjie Li
Mastering the high strain characteristics at cryogenics and constructing an accurate constitutive model are critical for establishing a cryogenic cutting simulation of Ti-6Al-4V alloy. The traditional constitutive model is inadequate for accounting for high and cryogenic conditions. In this paper, cryogenic split Hopkinson pressure bar (SHPB) experiments are conducted, specifically for Ti-6Al-4V alloy, to develop a modified Johnson–Cook (J–C) constitutive model that incorporates the cryogenic effect. A coupled two-dimensional orthogonal finite element simulation involving temperature displacement was conducted for the cryogenic cutting of Ti-6Al-4V alloy. This simulation was performed using ABAQUS, based on a modified J–C constitutive model subroutine. It was observed that the smallest discrepancy between the simulation results and the data from ice-fixed milling experiments was just 2.12%. The modified J–C constitutive model is more adept at simulating the chip morphology under cryogenic conditions. It was also found that cryogenic machining enhances the distribution of temperature and stress within the chip. For every 5°C reduction in processing temperature, the tool temperature diminishes by more than 2%.
{"title":"Modified constitutive models and cutting finite element simulation of Ti-6Al-4V alloy at cryogenic","authors":"Huaixin Lin, Gang Jin, Shaokun Luo, Guangyu Wang, Zhanjie Li","doi":"10.1177/09544062241266325","DOIUrl":"https://doi.org/10.1177/09544062241266325","url":null,"abstract":"Mastering the high strain characteristics at cryogenics and constructing an accurate constitutive model are critical for establishing a cryogenic cutting simulation of Ti-6Al-4V alloy. The traditional constitutive model is inadequate for accounting for high and cryogenic conditions. In this paper, cryogenic split Hopkinson pressure bar (SHPB) experiments are conducted, specifically for Ti-6Al-4V alloy, to develop a modified Johnson–Cook (J–C) constitutive model that incorporates the cryogenic effect. A coupled two-dimensional orthogonal finite element simulation involving temperature displacement was conducted for the cryogenic cutting of Ti-6Al-4V alloy. This simulation was performed using ABAQUS, based on a modified J–C constitutive model subroutine. It was observed that the smallest discrepancy between the simulation results and the data from ice-fixed milling experiments was just 2.12%. The modified J–C constitutive model is more adept at simulating the chip morphology under cryogenic conditions. It was also found that cryogenic machining enhances the distribution of temperature and stress within the chip. For every 5°C reduction in processing temperature, the tool temperature diminishes by more than 2%.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.1177/09544062241260566
Marko Todorović, Goran Marković, Radovan Bulatović, Marina Bošković, Mile Savković
Polynomials of a degree higher than 8th used for the rise phase of displacement curve of a cam profile were optimized for gaining minimal jerk using the search and rescue optimization algorithm. The algorithm was used to obtain the polynomial coefficients for the polynomials of the higher degree that cannot be calculated by using the analytical approach without adding additional boundary conditions other than displacement, velocity and acceleration in characteristic positions. The degree of the polynomial from which the optimal value of jerk using the optimization algorithm can be obtained was determined, as well as the degree after which the results of the optimization give worse values of the jerk.
{"title":"Cam displacement curve optimization for minimal jerk using search and rescue optimization algorithm","authors":"Marko Todorović, Goran Marković, Radovan Bulatović, Marina Bošković, Mile Savković","doi":"10.1177/09544062241260566","DOIUrl":"https://doi.org/10.1177/09544062241260566","url":null,"abstract":"Polynomials of a degree higher than 8th used for the rise phase of displacement curve of a cam profile were optimized for gaining minimal jerk using the search and rescue optimization algorithm. The algorithm was used to obtain the polynomial coefficients for the polynomials of the higher degree that cannot be calculated by using the analytical approach without adding additional boundary conditions other than displacement, velocity and acceleration in characteristic positions. The degree of the polynomial from which the optimal value of jerk using the optimization algorithm can be obtained was determined, as well as the degree after which the results of the optimization give worse values of the jerk.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-31DOI: 10.1177/09544062241266069
Yanwei Yuan, Jianmei Wang, Lu Ren, Jiguang Chen
The operational safety and stability of wind turbines are highly determined by the characteristics of main bearings, which are influenced by the axial clearance. In this paper, for the arrangement type of double-supported tapered roller bearings on the wind turbine main shaft, the actual clearance distribution assumption is established, and a new method of calculating the internal load distribution taking into account the axial clearance is proposed. Firstly, the mathematical relationship between the clearance of tapered roller bearings and ring displacement, contact deformation, and load interval is described. Secondly, the load components of main bearings are calculated by force balance equation and load-displacement condition. Finally, a mathematical model of main bearings including axial clearance is established, and it is numerically solved to obtain the internal load distribution of the bearings. The calculation results of a large megawatt wind turbine example show that: the axial load of both main bearings is negatively correlated with the sum of axial clearances; the number of loaded rolling elements is negatively correlated with the sum of axial clearances; and there exists an optimal value of the sum of axial clearances for main bearings to reach the optimal load carrying state.
{"title":"Influence of axial clearance on load distribution in double supported tapered roller bearings of wind turbine main shaft","authors":"Yanwei Yuan, Jianmei Wang, Lu Ren, Jiguang Chen","doi":"10.1177/09544062241266069","DOIUrl":"https://doi.org/10.1177/09544062241266069","url":null,"abstract":"The operational safety and stability of wind turbines are highly determined by the characteristics of main bearings, which are influenced by the axial clearance. In this paper, for the arrangement type of double-supported tapered roller bearings on the wind turbine main shaft, the actual clearance distribution assumption is established, and a new method of calculating the internal load distribution taking into account the axial clearance is proposed. Firstly, the mathematical relationship between the clearance of tapered roller bearings and ring displacement, contact deformation, and load interval is described. Secondly, the load components of main bearings are calculated by force balance equation and load-displacement condition. Finally, a mathematical model of main bearings including axial clearance is established, and it is numerically solved to obtain the internal load distribution of the bearings. The calculation results of a large megawatt wind turbine example show that: the axial load of both main bearings is negatively correlated with the sum of axial clearances; the number of loaded rolling elements is negatively correlated with the sum of axial clearances; and there exists an optimal value of the sum of axial clearances for main bearings to reach the optimal load carrying state.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1177/09544062241255987
Hongrui Cao, Olga Fink, Emeritus Fengshou Gu
{"title":"Machine condition monitoring, fault diagnosis/prognosis, and maintenance","authors":"Hongrui Cao, Olga Fink, Emeritus Fengshou Gu","doi":"10.1177/09544062241255987","DOIUrl":"https://doi.org/10.1177/09544062241255987","url":null,"abstract":"","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Uniform thickness belleville springs(UBS) are a suitable replacement for coil springs in many applications due to their ability to take higher loads and their relatively small and compact size. This paper presents an experimental, numerical and theoretical analysis of the taper belleville spring(TBS). Experimental results on a normal taper belleville spring (NTBS), fabricated from stainless steel alloy (SS304), are presented. Non linear elastic-plastic finite element simulations support the experimental behaviour reasonably well. A correction factor based on Timoshenko’s theory of plates, to match the finite element analysis(FEA) results for NTBS, is presented. Reverse taper belleville spring (RTBS) analysis shows that it can store more elastic strain energy than UBS and NTBS. An optimisation study on TBS geometrical parameters is performed to attain maximum energy absorption for the null stiffness region.
{"title":"Experimental, numerical, and theoretical analysis of tapered belleville spring","authors":"Umesh Singh, Manish Trikha, K.R.Y Simha, Ashitava Ghosal","doi":"10.1177/09544062241266142","DOIUrl":"https://doi.org/10.1177/09544062241266142","url":null,"abstract":"Uniform thickness belleville springs(UBS) are a suitable replacement for coil springs in many applications due to their ability to take higher loads and their relatively small and compact size. This paper presents an experimental, numerical and theoretical analysis of the taper belleville spring(TBS). Experimental results on a normal taper belleville spring (NTBS), fabricated from stainless steel alloy (SS304), are presented. Non linear elastic-plastic finite element simulations support the experimental behaviour reasonably well. A correction factor based on Timoshenko’s theory of plates, to match the finite element analysis(FEA) results for NTBS, is presented. Reverse taper belleville spring (RTBS) analysis shows that it can store more elastic strain energy than UBS and NTBS. An optimisation study on TBS geometrical parameters is performed to attain maximum energy absorption for the null stiffness region.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1177/09544062241264751
Kui Chen, Yongsheng Zhao, Jigui Zheng, Jianhui Wang, Yongqiang Dou
Time-varying loads, manufacturing errors, and assembly errors are the main factors leading to the performance degradation of the planetary roller screw mechanism. This paper proposes a comprehensive analysis method for the performance degradation of the planetary roller screw mechanism caused by time-varying loads and manufacturing and assembly errors. Firstly, a simulation analysis model of the planetary roller screw mechanism was established and its effectiveness was verified. A quantitative analysis was conducted on the influence of manufacturing and assembly errors on the load distribution, revealing the load-bearing mechanism under the influence of errors. Secondly, loading experiments were conducted on the planetary roller screw mechanism, and the degradation of its load-bearing performance was divided into the normal degradation stage, the accelerated degradation stage, and the failure stage. The experimental results prove that the initial transmission accuracy has a significant impact on the degradation of the load-bearing performance, determining the occurrence of the node where the accelerated degradation stage appears in the load-bearing performance. Thirdly, the wear status of the threads and gears was examined, and the results showed that material peeling was the main factor causing the degradation of load-bearing performance.
{"title":"A comprehensive analysis method of the performance degradation of planetary roller screws under the time-varying load and errors","authors":"Kui Chen, Yongsheng Zhao, Jigui Zheng, Jianhui Wang, Yongqiang Dou","doi":"10.1177/09544062241264751","DOIUrl":"https://doi.org/10.1177/09544062241264751","url":null,"abstract":"Time-varying loads, manufacturing errors, and assembly errors are the main factors leading to the performance degradation of the planetary roller screw mechanism. This paper proposes a comprehensive analysis method for the performance degradation of the planetary roller screw mechanism caused by time-varying loads and manufacturing and assembly errors. Firstly, a simulation analysis model of the planetary roller screw mechanism was established and its effectiveness was verified. A quantitative analysis was conducted on the influence of manufacturing and assembly errors on the load distribution, revealing the load-bearing mechanism under the influence of errors. Secondly, loading experiments were conducted on the planetary roller screw mechanism, and the degradation of its load-bearing performance was divided into the normal degradation stage, the accelerated degradation stage, and the failure stage. The experimental results prove that the initial transmission accuracy has a significant impact on the degradation of the load-bearing performance, determining the occurrence of the node where the accelerated degradation stage appears in the load-bearing performance. Thirdly, the wear status of the threads and gears was examined, and the results showed that material peeling was the main factor causing the degradation of load-bearing performance.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-28DOI: 10.1177/09544062241264263
Kun Li, Yunpeng Zhao, Yunhao Zhao, Hengji Cui, Zhiyu Han, Lei Zhao
Shoulder rehabilitation exoskeleton is a mechanical device to assist stroke patients in rehabilitation training, remodeling patients' neurological function by strengthening the muscles and promoting the recovery of shoulder function. At present, there are problems such as insufficient degree of freedom (DOF), insufficient overall range of motion (ROM), presence of passive joints, lack of the support of scapulohumeral rhythm (SHR), and poor kinematic synergy with the shoulder. This paper designs a 5-DOF shoulder rehabilitation exoskeleton based on the anatomical structure of the human shoulder and its motion characteristics, takes the 2-DOF shoulder girdle mechanism and the 3-DOF ball and socket mechanism as the main body taking into account the ergonomic factors in design, which ensures the synergistic motion with the patient's shoulder and provides the patient with a wide ROM. After setting up the drive and control system, this paper completes the prototype of the exoskeleton, furthermore, this paper describes the range of motion and kinematic synergy test. ROM tests and kinematic synergy experiments are conducted to evaluate the kinematic performance of this shoulder exoskeleton. The experimental results indicate that the shoulder exoskeleton prototype offers a high level of kinematic synergy with the wearer throughout a broad ROM.
{"title":"Mechanical design and kinematic performance of an anthropomorphic shoulder rehabilitation exoskeleton","authors":"Kun Li, Yunpeng Zhao, Yunhao Zhao, Hengji Cui, Zhiyu Han, Lei Zhao","doi":"10.1177/09544062241264263","DOIUrl":"https://doi.org/10.1177/09544062241264263","url":null,"abstract":"Shoulder rehabilitation exoskeleton is a mechanical device to assist stroke patients in rehabilitation training, remodeling patients' neurological function by strengthening the muscles and promoting the recovery of shoulder function. At present, there are problems such as insufficient degree of freedom (DOF), insufficient overall range of motion (ROM), presence of passive joints, lack of the support of scapulohumeral rhythm (SHR), and poor kinematic synergy with the shoulder. This paper designs a 5-DOF shoulder rehabilitation exoskeleton based on the anatomical structure of the human shoulder and its motion characteristics, takes the 2-DOF shoulder girdle mechanism and the 3-DOF ball and socket mechanism as the main body taking into account the ergonomic factors in design, which ensures the synergistic motion with the patient's shoulder and provides the patient with a wide ROM. After setting up the drive and control system, this paper completes the prototype of the exoskeleton, furthermore, this paper describes the range of motion and kinematic synergy test. ROM tests and kinematic synergy experiments are conducted to evaluate the kinematic performance of this shoulder exoskeleton. The experimental results indicate that the shoulder exoskeleton prototype offers a high level of kinematic synergy with the wearer throughout a broad ROM.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141796676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-27DOI: 10.1177/09544062241264939
Diviya Mariya Louis, Subramanian Manivel, Kaliappan Seeniappan, N. L
The AM60B magnesium alloy remains a pivotal player in the pursuit of lighter, biodegradable and more sustainable solutions for various biomedical implants because of its excellent machinability, exceptional strength and resistance to degradation. However, AM60B magnesium alloys exhibit poor machinability when machined by conventional methods, since they are susceptible to deformation and degradation at elevated temperatures. The current work focused on multiresponse optimization for AM60B magnesium alloys for wire electrical discharge machining (WEDM), where multiple output variables including the machining rate, surface irregularity, and microindentation hardness, were considered simultaneously. Response surface methodology (RSM) along with artificial neural network (ANN) were utilized to investigate the effect of these parameters on the control of these output characteristics. The findings demonstrated the best combination of input specifications, with a discharge duration of 112.743 µs, a spark gap time of 57.6532 µs, a discharge voltage of 6.63 V and a wire advance rate of 5.39357 mm/min which yielded the best surface irregularity, microindentation hardness, and machining rate from the RSM. ANN and RSM models were effective in simulating the experiments, with predicted values closely aligning with the experimental results. An optimally trained network model exhibited good agreement with a mean error less than 5%. Additionally, the condition of the machined surface, including any cracks, voids, or other flaws, was examined using scanning electron microscope (SEM).
{"title":"Multiresponse optimization and network-based prediction modelling for the WEDM of AM60B biomedical material","authors":"Diviya Mariya Louis, Subramanian Manivel, Kaliappan Seeniappan, N. L","doi":"10.1177/09544062241264939","DOIUrl":"https://doi.org/10.1177/09544062241264939","url":null,"abstract":"The AM60B magnesium alloy remains a pivotal player in the pursuit of lighter, biodegradable and more sustainable solutions for various biomedical implants because of its excellent machinability, exceptional strength and resistance to degradation. However, AM60B magnesium alloys exhibit poor machinability when machined by conventional methods, since they are susceptible to deformation and degradation at elevated temperatures. The current work focused on multiresponse optimization for AM60B magnesium alloys for wire electrical discharge machining (WEDM), where multiple output variables including the machining rate, surface irregularity, and microindentation hardness, were considered simultaneously. Response surface methodology (RSM) along with artificial neural network (ANN) were utilized to investigate the effect of these parameters on the control of these output characteristics. The findings demonstrated the best combination of input specifications, with a discharge duration of 112.743 µs, a spark gap time of 57.6532 µs, a discharge voltage of 6.63 V and a wire advance rate of 5.39357 mm/min which yielded the best surface irregularity, microindentation hardness, and machining rate from the RSM. ANN and RSM models were effective in simulating the experiments, with predicted values closely aligning with the experimental results. An optimally trained network model exhibited good agreement with a mean error less than 5%. Additionally, the condition of the machined surface, including any cracks, voids, or other flaws, was examined using scanning electron microscope (SEM).","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141797781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-26DOI: 10.1177/09544062241263412
Nurul Farhana Mohd Yusof, Zaidi Mohd Ripin
This paper presents the experimental and finite element analysis of surface asperity geometry during the running-in phase of rolling contact. Previous research efforts typically relied on simulating various shapes of asperity geometry to elucidate rough surface characteristics. However, this approximation did not accurately represent the actual surface asperities. In this study, a rolling contact rig was fabricated, and periodic surface scans were utilized to track the deformation of roller surface asperities. The experimental findings reveal a notable 69% reduction in surface roughness throughout the running-in phase, alongside showcasing the deformation of asperity geometry. Subsequently, a simulation model is developed using data derived from these experiments. Stress analysis conducted on individual and multiple asperities illustrates a decrease in contact stress over time, indicating a transition in contact behavior from plastic to elastic. Furthermore, simulations involving multiple asperities demonstrate an expansion in contact length as roughness diminishes with increasing cycles. Initially, only the highest peaks of asperities make contact, resulting in elevated contact stress. However, as rolling cycles progress, a greater number of asperities come into contact, leading to a more uniform distribution of load. Notably, the more prominent asperities endure significant contact stress and deformation compared to their smaller counterparts.
{"title":"Experimental and finite element analysis of surface asperity geometry during the running-in phase of rolling contact","authors":"Nurul Farhana Mohd Yusof, Zaidi Mohd Ripin","doi":"10.1177/09544062241263412","DOIUrl":"https://doi.org/10.1177/09544062241263412","url":null,"abstract":"This paper presents the experimental and finite element analysis of surface asperity geometry during the running-in phase of rolling contact. Previous research efforts typically relied on simulating various shapes of asperity geometry to elucidate rough surface characteristics. However, this approximation did not accurately represent the actual surface asperities. In this study, a rolling contact rig was fabricated, and periodic surface scans were utilized to track the deformation of roller surface asperities. The experimental findings reveal a notable 69% reduction in surface roughness throughout the running-in phase, alongside showcasing the deformation of asperity geometry. Subsequently, a simulation model is developed using data derived from these experiments. Stress analysis conducted on individual and multiple asperities illustrates a decrease in contact stress over time, indicating a transition in contact behavior from plastic to elastic. Furthermore, simulations involving multiple asperities demonstrate an expansion in contact length as roughness diminishes with increasing cycles. Initially, only the highest peaks of asperities make contact, resulting in elevated contact stress. However, as rolling cycles progress, a greater number of asperities come into contact, leading to a more uniform distribution of load. Notably, the more prominent asperities endure significant contact stress and deformation compared to their smaller counterparts.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-26DOI: 10.1177/09544062241262654
Ran Xie, Yuhu Yang, Guocheng Zhou, Ben Gao, Yunlei Jiao, Ruijiang Yu
This paper presents an approach for designing a novel tooth profile of harmonic drives, which is composed of two pieces of curves, hypocycloid and epicycloid, generated by the rolling circles with appropriate radii. Compared with the conventional double-circular-arc or cycloidal tooth profile of harmonic drives, the tooth profile is characterized by full conjugation, more number of engaged teeth, and can be expressed analytically, etc. Firstly, the generation of the cycloids are briefly described, and then their conjugate criterion is investigated systematically based on Camus’s theorem. Secondly, the tooth profile equations for the circular spline and flexspline are established and the deformed neutral curve equation is derived. Next, the contact properties among the tooth profiles, including the line of action, meshing angle, etc., are studied systematically. Finally, a finite element model and a physical prototype for the harmonic drive with the tooth profile are developed, respectively. The effectiveness of the design method is verified by the contact performances simulation. The research may provide a new thought for the innovative design of harmonic drives with full conjugate tooth profile.
{"title":"A novel harmonic drive with the full conjugate tooth profile","authors":"Ran Xie, Yuhu Yang, Guocheng Zhou, Ben Gao, Yunlei Jiao, Ruijiang Yu","doi":"10.1177/09544062241262654","DOIUrl":"https://doi.org/10.1177/09544062241262654","url":null,"abstract":"This paper presents an approach for designing a novel tooth profile of harmonic drives, which is composed of two pieces of curves, hypocycloid and epicycloid, generated by the rolling circles with appropriate radii. Compared with the conventional double-circular-arc or cycloidal tooth profile of harmonic drives, the tooth profile is characterized by full conjugation, more number of engaged teeth, and can be expressed analytically, etc. Firstly, the generation of the cycloids are briefly described, and then their conjugate criterion is investigated systematically based on Camus’s theorem. Secondly, the tooth profile equations for the circular spline and flexspline are established and the deformed neutral curve equation is derived. Next, the contact properties among the tooth profiles, including the line of action, meshing angle, etc., are studied systematically. Finally, a finite element model and a physical prototype for the harmonic drive with the tooth profile are developed, respectively. The effectiveness of the design method is verified by the contact performances simulation. The research may provide a new thought for the innovative design of harmonic drives with full conjugate tooth profile.","PeriodicalId":20558,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}