The active tilt-controlled narrow three-wheelers (3Ws) equipped with a closed cabin aim to offer a comfortable driving experience comparable to four-wheelers while maintaining the manoeuvrability of two-wheelers without compromising on speed. Based on this concept, this study explores a tilt control strategy for narrow 3Ws. While previous research has established a steady-state tilt angle considering a zero-track width, this study incorporates track width due to the multi-wheel axle configuration. This novel approach not only withstands unbalanced lateral acceleration but also saves significant tilting torque. Unnecessary tilting is minimised by introducing a tilt actuation system (TAS) based on a unique dynamic rollover index. Central to the original contribution is the stability margin (SM), a dynamic rollover-safety index considering longitudinal and lateral dynamics, surpassing the traditional rollover index load transfer ratio, particularly for delta 3Ws. This work proposes a desired SM threshold-dependent steady-state tilt angle, activating TAS only when necessary. This pioneering method optimises the desired SM threshold using goal programming. Additionally, this research addresses a critical oversight in previous studies by accounting for the influence of road slopes, ensuring consistent stability across diverse road conditions. It is crucial to note that the proposed rollover index-based tilting approach markedly outperforms the conventional methods, reinforcing its originality and potential for future vehicular design.
{"title":"Dynamic rollover-safety index-based tilt optimisation encompassing road configurations for narrow three-wheelers: Balancing energy efficiency and ride comfort","authors":"Ankitkumar Dandiwala, Basab Chakraborty, Debashish Chakravarty","doi":"10.1177/14644193231207496","DOIUrl":"https://doi.org/10.1177/14644193231207496","url":null,"abstract":"The active tilt-controlled narrow three-wheelers (3Ws) equipped with a closed cabin aim to offer a comfortable driving experience comparable to four-wheelers while maintaining the manoeuvrability of two-wheelers without compromising on speed. Based on this concept, this study explores a tilt control strategy for narrow 3Ws. While previous research has established a steady-state tilt angle considering a zero-track width, this study incorporates track width due to the multi-wheel axle configuration. This novel approach not only withstands unbalanced lateral acceleration but also saves significant tilting torque. Unnecessary tilting is minimised by introducing a tilt actuation system (TAS) based on a unique dynamic rollover index. Central to the original contribution is the stability margin (SM), a dynamic rollover-safety index considering longitudinal and lateral dynamics, surpassing the traditional rollover index load transfer ratio, particularly for delta 3Ws. This work proposes a desired SM threshold-dependent steady-state tilt angle, activating TAS only when necessary. This pioneering method optimises the desired SM threshold using goal programming. Additionally, this research addresses a critical oversight in previous studies by accounting for the influence of road slopes, ensuring consistent stability across diverse road conditions. It is crucial to note that the proposed rollover index-based tilting approach markedly outperforms the conventional methods, reinforcing its originality and potential for future vehicular design.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135371917","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 : 2023-10-23DOI: 10.1177/14644193231208532
Jie Wang, Zhiqiang Huang, Jian Li, Tao Li, Dequan Mu, Shuo Wang
With the rapid development of shale gas resources in China, there is an increasing demand for large and multiple column compressors. However, this development has brought to light the issue of torsional vibration in compressor crankshaft systems, particularly under variable loads and multiple working conditions. In order to reduce the torsional vibration of the compressor crankshaft and ensure the safe and stable operation of the compressor unit, this study proposes a method for calculating and suppressing torsional vibration in the crankshaft system of a shale gas compressor, which takes into account the flexibility effect of various parts and considers multiple working conditions. The analysis focused on the rigid-flexible coupling torsional vibration characteristics of the crankshaft system under multiple working conditions, considering the flexible deformation of the main bearing, connecting rod, and crankshaft. The study successfully determined the torsional vibration response of the crankshaft system under seven typical working conditions. Furthermore, for the worst conditions, a detailed analysis of the vibration response of the crankshaft system was conducted and carried out a study on suppressing crankshaft torsional vibration through response surface optimization design. The study findings indicate that the compressor system exhibits low-frequency vibrations during operation. The maximum torsional angular deformation at the crank pin of the fourth column is measured to be 0.052°. Following structural optimization, the relative torsional angular deformation of the crank pin is reduced by 25.61% under the worst operating conditions. Moreover, the peak angular velocity of the center of mass is reduced by 22.17%. These results demonstrate a significant suppression effect on torsional vibrations in the compressor crankshaft system, leading to improved working safety.
{"title":"Analysis of rigid-flexible coupled torsional vibration and vibration suppression of crankshaft system under multiple working conditions","authors":"Jie Wang, Zhiqiang Huang, Jian Li, Tao Li, Dequan Mu, Shuo Wang","doi":"10.1177/14644193231208532","DOIUrl":"https://doi.org/10.1177/14644193231208532","url":null,"abstract":"With the rapid development of shale gas resources in China, there is an increasing demand for large and multiple column compressors. However, this development has brought to light the issue of torsional vibration in compressor crankshaft systems, particularly under variable loads and multiple working conditions. In order to reduce the torsional vibration of the compressor crankshaft and ensure the safe and stable operation of the compressor unit, this study proposes a method for calculating and suppressing torsional vibration in the crankshaft system of a shale gas compressor, which takes into account the flexibility effect of various parts and considers multiple working conditions. The analysis focused on the rigid-flexible coupling torsional vibration characteristics of the crankshaft system under multiple working conditions, considering the flexible deformation of the main bearing, connecting rod, and crankshaft. The study successfully determined the torsional vibration response of the crankshaft system under seven typical working conditions. Furthermore, for the worst conditions, a detailed analysis of the vibration response of the crankshaft system was conducted and carried out a study on suppressing crankshaft torsional vibration through response surface optimization design. The study findings indicate that the compressor system exhibits low-frequency vibrations during operation. The maximum torsional angular deformation at the crank pin of the fourth column is measured to be 0.052°. Following structural optimization, the relative torsional angular deformation of the crank pin is reduced by 25.61% under the worst operating conditions. Moreover, the peak angular velocity of the center of mass is reduced by 22.17%. These results demonstrate a significant suppression effect on torsional vibrations in the compressor crankshaft system, leading to improved working safety.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135414771","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 : 2023-10-09DOI: 10.1177/14644193231203592
Chao Liu, Jinfu Du, Zongde Fang, Long Xiang, Shengyang Hu, Fang Guo, Pengfei Li
In this paper, a new modelling approach is proposed for the dynamic investigation of epicyclic gear train, and the novelty of this work lies in consideration of both structural flexibility and mechanical interactions during the analysis procedure. The method is of capacity to directly present the dynamic results of the supporting structure for convenient practical engineering evaluation and reduce the dimension of the system reasonably with appropriate assumptions for better computational efficiency. Firstly, the mechanical interactions among components are discussed in detail, and the principle that the structural flexibility works is also explained at length. Secondly, taking the epicyclic gear train of the geared turbofan (GTF) engine; for example, the dynamic model of the system is then established based on the developed hybrid user-defined elements. For model validation, the governing equations of the system are also derived by the lumped mass method. Thirdly, with the same values of the parameters, the results of normal dynamic meshing force obtained by the proposed model are compared with the ones by the lumped mass model. It can be stated from the data that (1) the maximum relative error between the theoretical value and the average value calculated by the two models is 8.28%, (2) the gear mesh frequency obtained by the two models are sufficiently close to the theoretical value, and (3) the fluctuation trends of the dynamic force keep basically consistent with each other. In summary, the comparison presented clearly indicates that the proposed model is indeed reasonable, which provides a new way for dynamic investigation and structural redesign of a large epicyclic gear train. Finally, as a practical engineering application, the vibration result of the deformable supporting structure of the GTF gear train is also presented, which directly provides valuable reference for vibration monitoring, fault diagnosis and other engineering problems in practice.
{"title":"An effective modelling approach for multi-body dynamic analysis of epicyclic gear train of GTF considering both structural flexibility and mechanical interactions","authors":"Chao Liu, Jinfu Du, Zongde Fang, Long Xiang, Shengyang Hu, Fang Guo, Pengfei Li","doi":"10.1177/14644193231203592","DOIUrl":"https://doi.org/10.1177/14644193231203592","url":null,"abstract":"In this paper, a new modelling approach is proposed for the dynamic investigation of epicyclic gear train, and the novelty of this work lies in consideration of both structural flexibility and mechanical interactions during the analysis procedure. The method is of capacity to directly present the dynamic results of the supporting structure for convenient practical engineering evaluation and reduce the dimension of the system reasonably with appropriate assumptions for better computational efficiency. Firstly, the mechanical interactions among components are discussed in detail, and the principle that the structural flexibility works is also explained at length. Secondly, taking the epicyclic gear train of the geared turbofan (GTF) engine; for example, the dynamic model of the system is then established based on the developed hybrid user-defined elements. For model validation, the governing equations of the system are also derived by the lumped mass method. Thirdly, with the same values of the parameters, the results of normal dynamic meshing force obtained by the proposed model are compared with the ones by the lumped mass model. It can be stated from the data that (1) the maximum relative error between the theoretical value and the average value calculated by the two models is 8.28%, (2) the gear mesh frequency obtained by the two models are sufficiently close to the theoretical value, and (3) the fluctuation trends of the dynamic force keep basically consistent with each other. In summary, the comparison presented clearly indicates that the proposed model is indeed reasonable, which provides a new way for dynamic investigation and structural redesign of a large epicyclic gear train. Finally, as a practical engineering application, the vibration result of the deformable supporting structure of the GTF gear train is also presented, which directly provides valuable reference for vibration monitoring, fault diagnosis and other engineering problems in practice.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135095754","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 : 2023-09-24DOI: 10.1177/14644193231203598
Tuan Anh Nguyen
Using stabilizer bars in cars to limit rollover is a necessity applied to many vehicles today. In this article, the author proposes using a new fuzzy method to control the hydraulic stabilizer bars. Previous studies only focused on improving the roll stability of cars, while this article focuses on ensuring both the roll stability and ride comfort of the vehicle, which is considered the new contribution of the article. Vehicle oscillations are described through a complex nonlinear dynamic model. The MATLAB ® application performs the simulation with two specific cases, including fish-hook steering and J-turn steering. According to the findings of this research, the roll angle value is significantly reduced when using active stabilizer bars directed by the novel algorithm. In addition, the risk of the rollover was also strongly reduced for both simulations (there are four-speed thresholds used in each case). For the first case, rollover does not occur when the car utilizes active stabilizer bars, even when travelling at v 4 = 100 (km/h). In the other case, the rollover occurs only for the Active situation when travelling at a very high speed. In contrast, this phenomenon occurs in the None situation at v 1 and the Passive situation at v 2 . The results found from this work help to evaluate the performance of the fuzzy control algorithm for active stabilizer bars.
{"title":"Proposing a novel fuzzy control algorithm for automotive active stabilizer bars based on views of roll stability and ride comfort","authors":"Tuan Anh Nguyen","doi":"10.1177/14644193231203598","DOIUrl":"https://doi.org/10.1177/14644193231203598","url":null,"abstract":"Using stabilizer bars in cars to limit rollover is a necessity applied to many vehicles today. In this article, the author proposes using a new fuzzy method to control the hydraulic stabilizer bars. Previous studies only focused on improving the roll stability of cars, while this article focuses on ensuring both the roll stability and ride comfort of the vehicle, which is considered the new contribution of the article. Vehicle oscillations are described through a complex nonlinear dynamic model. The MATLAB ® application performs the simulation with two specific cases, including fish-hook steering and J-turn steering. According to the findings of this research, the roll angle value is significantly reduced when using active stabilizer bars directed by the novel algorithm. In addition, the risk of the rollover was also strongly reduced for both simulations (there are four-speed thresholds used in each case). For the first case, rollover does not occur when the car utilizes active stabilizer bars, even when travelling at v 4 = 100 (km/h). In the other case, the rollover occurs only for the Active situation when travelling at a very high speed. In contrast, this phenomenon occurs in the None situation at v 1 and the Passive situation at v 2 . The results found from this work help to evaluate the performance of the fuzzy control algorithm for active stabilizer bars.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135925408","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 : 2023-09-12DOI: 10.1177/14644193231199723
Shuai Mo, Wenbin Liu, Xu Tang, Wei Zhang
To study the nonlinear dynamic characteristics of the electric drive transmission system of clean propulsion vehicles, a rotor-bearing system consisting of dual-stage meshing gear pairs and multiple loaded bearings was established. The influence of time-varying meshing stiffness, tooth side clearance, bearing clearance, and other factors were considered. A multi-degree of freedom vibration differential of the system was established equation, to analyze the vibration characteristics of various parts of the transmission system under different parameters. Using time-domain diagrams, poincaré cross-sections, bifurcation diagrams, and other images to study the vibration of gears. In addition, the primary resonance stability equation of the system is derived and its stability under different conditions is analyzed using meshing damping, stiffness, and load as variables. The results show that as the rotational speed increases, the first stage gear of the system undergoes the “single cycle-bifurcation-chaos-bifurcation-single cycle” vibration process, while the second stage gear undergoes two such processes. The instability intervals can be obtained as [3092,4859] and [8098,10896] r/min, [2797,3533] and [9423,14135] r/min respectively. Avoiding these speed ranges helps to improve the stability and safety of automotive motion.
{"title":"Research on nonlinear dynamics and primary resonance characteristics of electric drive gear transmission system for clean propulsion vehicles","authors":"Shuai Mo, Wenbin Liu, Xu Tang, Wei Zhang","doi":"10.1177/14644193231199723","DOIUrl":"https://doi.org/10.1177/14644193231199723","url":null,"abstract":"To study the nonlinear dynamic characteristics of the electric drive transmission system of clean propulsion vehicles, a rotor-bearing system consisting of dual-stage meshing gear pairs and multiple loaded bearings was established. The influence of time-varying meshing stiffness, tooth side clearance, bearing clearance, and other factors were considered. A multi-degree of freedom vibration differential of the system was established equation, to analyze the vibration characteristics of various parts of the transmission system under different parameters. Using time-domain diagrams, poincaré cross-sections, bifurcation diagrams, and other images to study the vibration of gears. In addition, the primary resonance stability equation of the system is derived and its stability under different conditions is analyzed using meshing damping, stiffness, and load as variables. The results show that as the rotational speed increases, the first stage gear of the system undergoes the “single cycle-bifurcation-chaos-bifurcation-single cycle” vibration process, while the second stage gear undergoes two such processes. The instability intervals can be obtained as [3092,4859] and [8098,10896] r/min, [2797,3533] and [9423,14135] r/min respectively. Avoiding these speed ranges helps to improve the stability and safety of automotive motion.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135830958","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 : 2023-09-01DOI: 10.1177/14644193231177866
Farzan Barin, Kourosh Heidari Shirazi, Hamid M. Sedighi
This work is a study on transient vibrational behaviour of a vehicle driveline system during tip-in/released/tip-out throttle. The considered vehicle is a passenger sedan, front-wheel drive, front-engine equipped with a four-stroke four-cylinder SI engine and a 5-speed manual transmission. The engine's model follows the mean value model including the effects both dynamics and combustion parameters including manifold/engine volume, air to fuel ratio, spark advance/retard and RPM on its transient indicator and brake torque behaviour. A primary fourteen-degrees-of-freedom lumped parameter torsional driveline model including, a multi-staged clutch with nonlinear clutch springs model and the gear backlash effect on idle as well as engaged gears is considered. This model is reduced to a six-degrees-of-freedom model. A rigid 2D model and magic formula are used for modelling of vehicle-tyre-road dynamics interaction. Using the overall model, the role of the driving style, the engine dynamics and longitudinal vehicle-road dynamic interaction in creating and intensifying the shuffle, clonk, and shunt, are studied and summarized, as the particular focus of this study. Although the results verify the other related researches on the importance of nonlinear parameters such as nonlinear stiffness, backlash and gear teeth impact, on the intensity of vibro-impact responses, they prove that engine's dynamics/combustion parameters such as engine volume, intake manifold volume and spark advance timing as well as driving style and also tyre-road parameters such as coefficient of friction and road grade have significant role in intensifying the vibro-impact responses. For example, (a) the smaller the engine, the larger amplitude the shuffle; (b) the sport driving style intensifies the both the clonk and the shuffle and (c) the more slippery road in time of the tip-out, the more strengthen the shuffle. The results of the overall driver/engine/driveline/tyre/road model provide more knowledge towards better understanding of vibro-impact response of the driveline.
{"title":"Classification of transient vibration of passenger cars powertrain","authors":"Farzan Barin, Kourosh Heidari Shirazi, Hamid M. Sedighi","doi":"10.1177/14644193231177866","DOIUrl":"https://doi.org/10.1177/14644193231177866","url":null,"abstract":"This work is a study on transient vibrational behaviour of a vehicle driveline system during tip-in/released/tip-out throttle. The considered vehicle is a passenger sedan, front-wheel drive, front-engine equipped with a four-stroke four-cylinder SI engine and a 5-speed manual transmission. The engine's model follows the mean value model including the effects both dynamics and combustion parameters including manifold/engine volume, air to fuel ratio, spark advance/retard and RPM on its transient indicator and brake torque behaviour. A primary fourteen-degrees-of-freedom lumped parameter torsional driveline model including, a multi-staged clutch with nonlinear clutch springs model and the gear backlash effect on idle as well as engaged gears is considered. This model is reduced to a six-degrees-of-freedom model. A rigid 2D model and magic formula are used for modelling of vehicle-tyre-road dynamics interaction. Using the overall model, the role of the driving style, the engine dynamics and longitudinal vehicle-road dynamic interaction in creating and intensifying the shuffle, clonk, and shunt, are studied and summarized, as the particular focus of this study. Although the results verify the other related researches on the importance of nonlinear parameters such as nonlinear stiffness, backlash and gear teeth impact, on the intensity of vibro-impact responses, they prove that engine's dynamics/combustion parameters such as engine volume, intake manifold volume and spark advance timing as well as driving style and also tyre-road parameters such as coefficient of friction and road grade have significant role in intensifying the vibro-impact responses. For example, (a) the smaller the engine, the larger amplitude the shuffle; (b) the sport driving style intensifies the both the clonk and the shuffle and (c) the more slippery road in time of the tip-out, the more strengthen the shuffle. The results of the overall driver/engine/driveline/tyre/road model provide more knowledge towards better understanding of vibro-impact response of the driveline.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86900354","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 : 2023-08-21DOI: 10.1177/14644193231195146
N. Xu, Chao Yang, Guangxue Yang, Zunsong Ren
Additional slosh forces and moments are generated owing to the movement of the liquid inside a partly filled tank car. The loads may have a great influence on the structure reliability and dynamic performance of the vehicle. An improved equivalent model of liquid sloshing is put forward to obtain the forces and moments of sloshing liquid acting on the tank during the lateral and longitudinal sloshing processes. An improved method is proposed to obtain the equivalent masses and stiffness for the improved equivalent model. The equivalent model is integrated into the multi-body dynamic model of a railway tank car with 68 degrees of freedom. Furthermore, the equivalent liquid-vehicle model is used to investigate the effects of fluid sloshing on dynamic characteristics. The influence of the filling ratio on the dynamic response of the tank car is discussed based on the forces and the corresponding moments between the tank car body and the liquid in different layers. The railway tank car is obviously influenced by the liquid sloshing during passing the curved and sloped tracks. The influence of liquid sloshing on the pitching motion of the tank is heavy if the tank is about half filled. The derailment coefficient and the wheel unloading rate are slightly influenced by the filling ratio of tank cars on curved tracks while the indices of the tank cars on sloped tracks are the greatest if the filling ratio is 40%.
{"title":"Effect of liquid sloshing in lateral and longitudinal directions on railway tank cars based on an improved equivalent model","authors":"N. Xu, Chao Yang, Guangxue Yang, Zunsong Ren","doi":"10.1177/14644193231195146","DOIUrl":"https://doi.org/10.1177/14644193231195146","url":null,"abstract":"Additional slosh forces and moments are generated owing to the movement of the liquid inside a partly filled tank car. The loads may have a great influence on the structure reliability and dynamic performance of the vehicle. An improved equivalent model of liquid sloshing is put forward to obtain the forces and moments of sloshing liquid acting on the tank during the lateral and longitudinal sloshing processes. An improved method is proposed to obtain the equivalent masses and stiffness for the improved equivalent model. The equivalent model is integrated into the multi-body dynamic model of a railway tank car with 68 degrees of freedom. Furthermore, the equivalent liquid-vehicle model is used to investigate the effects of fluid sloshing on dynamic characteristics. The influence of the filling ratio on the dynamic response of the tank car is discussed based on the forces and the corresponding moments between the tank car body and the liquid in different layers. The railway tank car is obviously influenced by the liquid sloshing during passing the curved and sloped tracks. The influence of liquid sloshing on the pitching motion of the tank is heavy if the tank is about half filled. The derailment coefficient and the wheel unloading rate are slightly influenced by the filling ratio of tank cars on curved tracks while the indices of the tank cars on sloped tracks are the greatest if the filling ratio is 40%.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73094632","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 : 2023-08-10DOI: 10.1177/14644193231194122
Minh Duc Dao
In recent years, the number of stroke patients has increased, which has led to an increased need for motor rehabilitation exercises. The application of automation devices in the rehabilitation of patients is becoming increasingly developed. These devices help reduce the patient training time and workload. Each type of equipment uses different actuators such as electric motors, pneumatic cylinders, and hydraulic cylinders. Different from previous studies, in this paper, a research model of lower extremity rehabilitation devices using a simple actuator which is a linear actuator is presented. The main contribution of this study is that a dynamic model of the linear actuator associated with the action dynamics of the lower extremities of the studied model with three degrees of freedom was established. A mathematical model for this actuator is also presented, simulating the response of the mechanism using the MATLAB/Simulink software. A lower extremity rehabilitation device using a linear actuator was manufactured and tested. The test results for 10 volunteers show that the actuator works and causes miniature angle errors. This experiment demonstrates that the linear actuator can be used in stroke patient rehabilitation equipment and contributes to the diversification of the mechanism in automation equipment.
{"title":"Modeling and control of the linear actuator for the lower limb rehabilitation device","authors":"Minh Duc Dao","doi":"10.1177/14644193231194122","DOIUrl":"https://doi.org/10.1177/14644193231194122","url":null,"abstract":"In recent years, the number of stroke patients has increased, which has led to an increased need for motor rehabilitation exercises. The application of automation devices in the rehabilitation of patients is becoming increasingly developed. These devices help reduce the patient training time and workload. Each type of equipment uses different actuators such as electric motors, pneumatic cylinders, and hydraulic cylinders. Different from previous studies, in this paper, a research model of lower extremity rehabilitation devices using a simple actuator which is a linear actuator is presented. The main contribution of this study is that a dynamic model of the linear actuator associated with the action dynamics of the lower extremities of the studied model with three degrees of freedom was established. A mathematical model for this actuator is also presented, simulating the response of the mechanism using the MATLAB/Simulink software. A lower extremity rehabilitation device using a linear actuator was manufactured and tested. The test results for 10 volunteers show that the actuator works and causes miniature angle errors. This experiment demonstrates that the linear actuator can be used in stroke patient rehabilitation equipment and contributes to the diversification of the mechanism in automation equipment.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80767734","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 : 2023-07-25DOI: 10.1177/14644193231188776
Shuai Mo, Xuan Huang, Wenbin Liu, W. Zhang
In order to explore the dynamic response and primary resonance characteristics of the gear transmission system of the helicopter main reducer. The face gear-planetary gear torsion-translation vibration dynamics model is established, and the time-varying meshing stiffness, gear backlashes, gear eccentricity error, and friction are considered. The four-order variable-step Runge–Kutta was used to solve the dynamic response of the system, and the nonlinear dynamic characteristics of the system were described by time domain diagram, phase trajectory plane, Poincaré map, 3D frequency spectrum, and bifurcation diagram. Additionally, using the face gear-spur gear system's transmission as an example, the multi-scale method is used to analyze the face gear-spur gear system's primary resonance characteristics. The influence of load fluctuation amplitude, meshing damping, and meshing stiffness on its amplitude-frequency characteristics is also investigated. It is found that when external load excitation frequency changes, the vibration response of the whole system changes synchronously, which exhibits periodic, multi-periodic, and chaotic motion. In addition, according to the primary resonance analysis, the system's stability will be harmed by increasing the external load fluctuations’ amplitude, lowering the meshing damping, and raising the meshing stiffness.
{"title":"Study on nonlinear vibration and primary resonance characteristics of helicopter face gear-planetary gear coupling transmission system","authors":"Shuai Mo, Xuan Huang, Wenbin Liu, W. Zhang","doi":"10.1177/14644193231188776","DOIUrl":"https://doi.org/10.1177/14644193231188776","url":null,"abstract":"In order to explore the dynamic response and primary resonance characteristics of the gear transmission system of the helicopter main reducer. The face gear-planetary gear torsion-translation vibration dynamics model is established, and the time-varying meshing stiffness, gear backlashes, gear eccentricity error, and friction are considered. The four-order variable-step Runge–Kutta was used to solve the dynamic response of the system, and the nonlinear dynamic characteristics of the system were described by time domain diagram, phase trajectory plane, Poincaré map, 3D frequency spectrum, and bifurcation diagram. Additionally, using the face gear-spur gear system's transmission as an example, the multi-scale method is used to analyze the face gear-spur gear system's primary resonance characteristics. The influence of load fluctuation amplitude, meshing damping, and meshing stiffness on its amplitude-frequency characteristics is also investigated. It is found that when external load excitation frequency changes, the vibration response of the whole system changes synchronously, which exhibits periodic, multi-periodic, and chaotic motion. In addition, according to the primary resonance analysis, the system's stability will be harmed by increasing the external load fluctuations’ amplitude, lowering the meshing damping, and raising the meshing stiffness.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76269641","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 : 2023-07-20DOI: 10.1177/14644193231189462
Xinbin Li, J. Liu, Zhifeng Shi, Yajun Xu, Yu Zhang
Cylindrical roller bearings are essential components in rotating mechanical systems, and ensuring their reliable operation is importance. Accurate modeling of cylindrical roller bearing defects is therefore crucial for enabling effective predictive maintenance strategies in various industries. However, previous studies have overlooked the presence of additional forces that occur when rollers enter and exit non-through defects, leading to inaccuracies in bearing vibration calculations. This work proposes a novel model that captures the bearing vibrations during this process, by considering the defect edge feature of the cylindrical roller bearings. The contact force between the roller and the defective ring is calculated by using the non-ideal Hertzian contact theory, while the additional force is characterized by a time-varying function based on the geometric relationship and Hertzian contact theory. To validate the proposed model, comparison work is carried out between the contact forces calculated using this model and those obtained from existing models, demonstrating the significance of the additional force during the process of rollers entering and exiting non-through defects. Furthermore, the effects of the outer ring defect width, length, and edge angle on cylindrical roller bearing vibrations are investigated and discussed. Compared with the previous studies, this work considers both the additional forces caused by the defect and defect edge feature, and combines the non-ideal Hertzian contact theory to obtain a more reasonable dynamic of the defective cylindrical roller bearings.
{"title":"Dynamic modeling of cylindrical roller bearings by considering non-through defects and additional forces","authors":"Xinbin Li, J. Liu, Zhifeng Shi, Yajun Xu, Yu Zhang","doi":"10.1177/14644193231189462","DOIUrl":"https://doi.org/10.1177/14644193231189462","url":null,"abstract":"Cylindrical roller bearings are essential components in rotating mechanical systems, and ensuring their reliable operation is importance. Accurate modeling of cylindrical roller bearing defects is therefore crucial for enabling effective predictive maintenance strategies in various industries. However, previous studies have overlooked the presence of additional forces that occur when rollers enter and exit non-through defects, leading to inaccuracies in bearing vibration calculations. This work proposes a novel model that captures the bearing vibrations during this process, by considering the defect edge feature of the cylindrical roller bearings. The contact force between the roller and the defective ring is calculated by using the non-ideal Hertzian contact theory, while the additional force is characterized by a time-varying function based on the geometric relationship and Hertzian contact theory. To validate the proposed model, comparison work is carried out between the contact forces calculated using this model and those obtained from existing models, demonstrating the significance of the additional force during the process of rollers entering and exiting non-through defects. Furthermore, the effects of the outer ring defect width, length, and edge angle on cylindrical roller bearing vibrations are investigated and discussed. Compared with the previous studies, this work considers both the additional forces caused by the defect and defect edge feature, and combines the non-ideal Hertzian contact theory to obtain a more reasonable dynamic of the defective cylindrical roller bearings.","PeriodicalId":54565,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part K-Journal of Multi-Body Dynamics","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90263918","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}