Pub Date : 2024-07-23DOI: 10.1177/09544070241252480
Junwu Zhao, Ting Qu, Yunfeng Hu
With the development of autonomous driving, future traffic will be composed of various participants. Integrating autonomous vehicles into the traffic flow composed of various types of traffic participants and minimizing conflicts between them is a critical research issue. Thus, this study presents a layered game-theoretic decision-making framework with situational awareness for autonomous vehicles, enabling adaptive decisions for autonomous vehicles in scenarios with multiple traffic participants of different driving characteristics. This paper’s situational awareness layer recognizes multiple participants’ politeness levels through their behavior and spatiotemporal relationships, allowing for a quantitative evaluation of their driving characteristics. The decision-making layer, built on Stackelberg game, adjusts the estimated cost of other traffic participants based on recognized politeness levels. The predictions of optimal behavior for traffic participants are obtained by minimizing the cost, according to which the optimal decision for the ego vehicle can be obtained. Besides, a set of parameters is used to construct the optimization problem as a convex optimization problem, so that the uniqueness of leader’s prediction of follower’s optimal action in each game can be guaranteed. To verify the feasibility and effectiveness, a trajectory planning layer for the autonomous vehicle is designed, the geometric safety constraint consists of planned trajectory and predicted trajectory of traffic participants are built to prevent collisions. Results indicate that the proposed framework can achieve balanced performance when interacting with traffic participants of different politeness levels.
{"title":"Interactive decision-making for autonomous vehicles: A layered game-theoretic framework with situational awareness","authors":"Junwu Zhao, Ting Qu, Yunfeng Hu","doi":"10.1177/09544070241252480","DOIUrl":"https://doi.org/10.1177/09544070241252480","url":null,"abstract":"With the development of autonomous driving, future traffic will be composed of various participants. Integrating autonomous vehicles into the traffic flow composed of various types of traffic participants and minimizing conflicts between them is a critical research issue. Thus, this study presents a layered game-theoretic decision-making framework with situational awareness for autonomous vehicles, enabling adaptive decisions for autonomous vehicles in scenarios with multiple traffic participants of different driving characteristics. This paper’s situational awareness layer recognizes multiple participants’ politeness levels through their behavior and spatiotemporal relationships, allowing for a quantitative evaluation of their driving characteristics. The decision-making layer, built on Stackelberg game, adjusts the estimated cost of other traffic participants based on recognized politeness levels. The predictions of optimal behavior for traffic participants are obtained by minimizing the cost, according to which the optimal decision for the ego vehicle can be obtained. Besides, a set of parameters is used to construct the optimization problem as a convex optimization problem, so that the uniqueness of leader’s prediction of follower’s optimal action in each game can be guaranteed. To verify the feasibility and effectiveness, a trajectory planning layer for the autonomous vehicle is designed, the geometric safety constraint consists of planned trajectory and predicted trajectory of traffic participants are built to prevent collisions. Results indicate that the proposed framework can achieve balanced performance when interacting with traffic participants of different politeness levels.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"2 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141784404","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}
To predict the classification of the pedestrian landing mechanism in pedestrian-vehicle collisions, 1303 reconstructed real pedestrian-vehicle collision cases were selected, and relevant data from before, during, and after the collisions were extracted. A total of 1303 sets of data with eight parameters were obtained via significance analysis, correlation analysis, and collinearity analysis. Then, the Backpropagation Neural Network (BPNN), Genetic Algorithm (GA) optimized BPNN (GA-BPNN), Principal Component Analysis (PCA) optimized BPNN (PCA-BPNN), Principal Component Analysis (PCA) and Genetic Algorithm (GA) optimized BPNN (PCA-GA-BPNN) were used to construct prediction models for the classification of the pedestrian landing mechanism, and the prediction effects were evaluated. The PCA-GA-BPNN model was found to be the optimal model; the prediction accuracies of the pre-collision, in-collision, and post-collision models were 72.4%, 96.4%, and 96.8%, respectively. Further analysis revealed that the optimal model could also accurately predict the classification of the pedestrian landing mechanism in six cadaver experiments. Additionally, the ratio of the pedestrian height to the vehicle hood height ( R P-V) was found to have an impact on the prediction effect of the model. Thus, an improved model considering R P-V was proposed, and was found to significantly improve the prediction accuracy of pedestrian forward-throwing mechanism. The research results provide new ideas for ground-related injury prediction, and also provide support for pedestrian protection in intelligent vehicles.
{"title":"Prediction of the classification of the pedestrian landing mechanism in pedestrian-vehicle collisions","authors":"Tiefang Zou, Pengchen Luo, Zhuzi Liu, Xiangting Yuan","doi":"10.1177/09544070241259899","DOIUrl":"https://doi.org/10.1177/09544070241259899","url":null,"abstract":"To predict the classification of the pedestrian landing mechanism in pedestrian-vehicle collisions, 1303 reconstructed real pedestrian-vehicle collision cases were selected, and relevant data from before, during, and after the collisions were extracted. A total of 1303 sets of data with eight parameters were obtained via significance analysis, correlation analysis, and collinearity analysis. Then, the Backpropagation Neural Network (BPNN), Genetic Algorithm (GA) optimized BPNN (GA-BPNN), Principal Component Analysis (PCA) optimized BPNN (PCA-BPNN), Principal Component Analysis (PCA) and Genetic Algorithm (GA) optimized BPNN (PCA-GA-BPNN) were used to construct prediction models for the classification of the pedestrian landing mechanism, and the prediction effects were evaluated. The PCA-GA-BPNN model was found to be the optimal model; the prediction accuracies of the pre-collision, in-collision, and post-collision models were 72.4%, 96.4%, and 96.8%, respectively. Further analysis revealed that the optimal model could also accurately predict the classification of the pedestrian landing mechanism in six cadaver experiments. Additionally, the ratio of the pedestrian height to the vehicle hood height ( R<jats:sub> P-V</jats:sub>) was found to have an impact on the prediction effect of the model. Thus, an improved model considering R<jats:sub> P-V</jats:sub> was proposed, and was found to significantly improve the prediction accuracy of pedestrian forward-throwing mechanism. The research results provide new ideas for ground-related injury prediction, and also provide support for pedestrian protection in intelligent vehicles.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"71 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141784405","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 : 2024-07-23DOI: 10.1177/09544070241253040
Vinay Prakash, Olivier Sauvage, Jérôme Antoni, Laurent Gagliardini, Nicolas Totaro
Despite the advantage of being quieter than traditional internal combustion engine vehicles, electric vehicles are often distinguished by high-frequency tonal components, which can be perceived as unpleasant to the occupants and the environment. To ensure optimal acoustic comfort in electric vehicles, it is important to analyze the NVH behavior of e-powertrains during the early stages of the design process which poses inherent uncertainties, such as varying operating conditions, partial knowledge of design parameters, dispersion in measurement-based data, etc. To effectively address these uncertainties, it is necessary to use fast and comprehensive stochastic models during the design phase. In this work, a probabilistic framework is presented to estimate the electric powertrain’s interior whining noises considering the structure-borne contribution. Hence, two different stochastic metamodels are developed for efficient quantification and propagation of uncertainties from electric motor stage to powertrain mounting system. Multivariate Bayesian regression models help to incorporate prior knowledge on the uncertain parameters and generate the respective posterior distributions using Markov chains Monte Carlo (MCMC) techniques. For this particular application, the data is generated through weakly-coupled multi-physical domains estimated using semi-analytical approaches and combined with measured vehicle transfer functions. Importantly, the validation of each domain is conducted separately to ensure accurate representation. The results obtained from the developed probabilistic framework will aid in the early design stages by guiding engineers in making informed decisions to optimize NVH performance.
{"title":"Stochastic assessment of electric powertrain whining noise under early-stage design uncertainties","authors":"Vinay Prakash, Olivier Sauvage, Jérôme Antoni, Laurent Gagliardini, Nicolas Totaro","doi":"10.1177/09544070241253040","DOIUrl":"https://doi.org/10.1177/09544070241253040","url":null,"abstract":"Despite the advantage of being quieter than traditional internal combustion engine vehicles, electric vehicles are often distinguished by high-frequency tonal components, which can be perceived as unpleasant to the occupants and the environment. To ensure optimal acoustic comfort in electric vehicles, it is important to analyze the NVH behavior of e-powertrains during the early stages of the design process which poses inherent uncertainties, such as varying operating conditions, partial knowledge of design parameters, dispersion in measurement-based data, etc. To effectively address these uncertainties, it is necessary to use fast and comprehensive stochastic models during the design phase. In this work, a probabilistic framework is presented to estimate the electric powertrain’s interior whining noises considering the structure-borne contribution. Hence, two different stochastic metamodels are developed for efficient quantification and propagation of uncertainties from electric motor stage to powertrain mounting system. Multivariate Bayesian regression models help to incorporate prior knowledge on the uncertain parameters and generate the respective posterior distributions using Markov chains Monte Carlo (MCMC) techniques. For this particular application, the data is generated through weakly-coupled multi-physical domains estimated using semi-analytical approaches and combined with measured vehicle transfer functions. Importantly, the validation of each domain is conducted separately to ensure accurate representation. The results obtained from the developed probabilistic framework will aid in the early design stages by guiding engineers in making informed decisions to optimize NVH performance.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"43 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141784417","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 : 2024-06-24DOI: 10.1177/09544070241256426
Xiangnan Liu, Xuepeng Qian, Yi Xi
The present study is focused on the development of a novel method for compiling load blocks to accelerate the fatigue bench test of rubber vibration isolators. This approach involves three main steps: Firstly, a uniaxial tensile fatigue test is conducted on rubber specimens under a constant amplitude load. According to the fatigue test data, a rubber fatigue life prediction model is established. Secondly, the mount load spectrum is statistically analyzed, and the fatigue damage distribution of the mount is calculated using the rubber fatigue life prediction model. Lastly, following the principle of damage equivalence, the load spectrum is compiled into load blocks. The fatigue bench test of the mount is then conducted using both the load spectrum and the load block as loading data, respectively. The test results demonstrate that the fatigue failure locations of the mounts are essentially identical under both loading data types, verifying the effectiveness of the proposed load block compilation method.
{"title":"Accelerated fatigue bench test method for rubber vibration isolators based on load spectrum compilation","authors":"Xiangnan Liu, Xuepeng Qian, Yi Xi","doi":"10.1177/09544070241256426","DOIUrl":"https://doi.org/10.1177/09544070241256426","url":null,"abstract":"The present study is focused on the development of a novel method for compiling load blocks to accelerate the fatigue bench test of rubber vibration isolators. This approach involves three main steps: Firstly, a uniaxial tensile fatigue test is conducted on rubber specimens under a constant amplitude load. According to the fatigue test data, a rubber fatigue life prediction model is established. Secondly, the mount load spectrum is statistically analyzed, and the fatigue damage distribution of the mount is calculated using the rubber fatigue life prediction model. Lastly, following the principle of damage equivalence, the load spectrum is compiled into load blocks. The fatigue bench test of the mount is then conducted using both the load spectrum and the load block as loading data, respectively. The test results demonstrate that the fatigue failure locations of the mounts are essentially identical under both loading data types, verifying the effectiveness of the proposed load block compilation method.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"17 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508161","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 : 2024-06-20DOI: 10.1177/09544070241257988
Sun Tingting, Zaidi Mohd Ripin, Chan Ping Yi, Mohamad Ikhwan Zaini Ridzwan
Frontal collisions of coaches contribute to more than half of the total number of casualties in traffic accidents, making it important to study frontal collisions of coaches. This literature review covers regulations, injury criteria, and factors influencing occupant injury, primarily referenced national standards on seat stability, and occupant safety. Existing regulations such as these are important because they highlight the injury criteria for the head, neck, chest and lower limbs of occupants. Injury criteria outside of the existing regulations are also highlighted, particularly the need to include both linear and angular accelerations of the head. In addition, numerous factors within the interior structure of a coach can impact injury severities. The use of different restraint systems and alterations in seat parameters can have varying effects on different limbs of the occupant during accidents. The researches show that three-point seat belts are advantageous and can protect occupants’ heads and necks, both adults and children. At the same time, proper seat spacing, seat inclination and other seat-related parameters also influence the injuries to the occupant’s head and neck. For example, occupant head injury risk is high when the seat inclination is between 105° and 115°, and occupant neck risk is high when the seat inclination is 95°. Future studies should evaluate the less-covered areas of occupant safety such as the safety of driver and co-driver. This review highlighted the critical need to update and enhance regulatory requirements based on current research findings to reduce the risk of occupant injury.
{"title":"Occupant safety and injuries in coach frontal collision: a literature review","authors":"Sun Tingting, Zaidi Mohd Ripin, Chan Ping Yi, Mohamad Ikhwan Zaini Ridzwan","doi":"10.1177/09544070241257988","DOIUrl":"https://doi.org/10.1177/09544070241257988","url":null,"abstract":"Frontal collisions of coaches contribute to more than half of the total number of casualties in traffic accidents, making it important to study frontal collisions of coaches. This literature review covers regulations, injury criteria, and factors influencing occupant injury, primarily referenced national standards on seat stability, and occupant safety. Existing regulations such as these are important because they highlight the injury criteria for the head, neck, chest and lower limbs of occupants. Injury criteria outside of the existing regulations are also highlighted, particularly the need to include both linear and angular accelerations of the head. In addition, numerous factors within the interior structure of a coach can impact injury severities. The use of different restraint systems and alterations in seat parameters can have varying effects on different limbs of the occupant during accidents. The researches show that three-point seat belts are advantageous and can protect occupants’ heads and necks, both adults and children. At the same time, proper seat spacing, seat inclination and other seat-related parameters also influence the injuries to the occupant’s head and neck. For example, occupant head injury risk is high when the seat inclination is between 105° and 115°, and occupant neck risk is high when the seat inclination is 95°. Future studies should evaluate the less-covered areas of occupant safety such as the safety of driver and co-driver. This review highlighted the critical need to update and enhance regulatory requirements based on current research findings to reduce the risk of occupant injury.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"68 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508162","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 : 2024-05-31DOI: 10.1177/09544070241249206
Xin Chen, Lifei Yang, Yingying Gong, Kaiqi Liu
Multi-material automotive structures enable precise material selection in each structure, leading to enhanced product performance at a reduced cost and achieving lightweight design objectives. This paper introduces an innovative method for material selection in the context of designing multi-material lightweight automotive bodies. The proposed approach integrates topology optimization, Entropy Weight (EW), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to apply optimal materials in specific locations strategically. The investigation centers on the body of a compact electric vehicle, leveraging topology optimization to ascertain load transfer paths and material distribution within the structure. The EW-TOPSIS method introduces a comprehensive mechanical property ranking method for materials, organizing scoring criteria across various materials. By combining this information with element density via topology optimization, a matching criterion and a corresponding relationship between vehicle body performance and material characteristics are established. Subsequently, the SFE-CONCEPT software is employed to generate an implicit parametric model of the body structure based on material distribution characteristics. The steps of the vehicle body structure reliability optimization design involve establishing a multi-objective optimization model, defining and screening design variables, analyzing the approximate model and errors, and conducting reliability optimization based on a second-generation genetic algorithm. After optimization, the body structure is reconstructed, resulting in a 3.49% reduction in mass, a 38.8% increase in bending stiffness, a 6.47% increase in torsional stiffness, and significantly enhanced collision safety performance.
{"title":"Lightweight design of multi-material body structure based on material selection method and implicit parametric modeling","authors":"Xin Chen, Lifei Yang, Yingying Gong, Kaiqi Liu","doi":"10.1177/09544070241249206","DOIUrl":"https://doi.org/10.1177/09544070241249206","url":null,"abstract":"Multi-material automotive structures enable precise material selection in each structure, leading to enhanced product performance at a reduced cost and achieving lightweight design objectives. This paper introduces an innovative method for material selection in the context of designing multi-material lightweight automotive bodies. The proposed approach integrates topology optimization, Entropy Weight (EW), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to apply optimal materials in specific locations strategically. The investigation centers on the body of a compact electric vehicle, leveraging topology optimization to ascertain load transfer paths and material distribution within the structure. The EW-TOPSIS method introduces a comprehensive mechanical property ranking method for materials, organizing scoring criteria across various materials. By combining this information with element density via topology optimization, a matching criterion and a corresponding relationship between vehicle body performance and material characteristics are established. Subsequently, the SFE-CONCEPT software is employed to generate an implicit parametric model of the body structure based on material distribution characteristics. The steps of the vehicle body structure reliability optimization design involve establishing a multi-objective optimization model, defining and screening design variables, analyzing the approximate model and errors, and conducting reliability optimization based on a second-generation genetic algorithm. After optimization, the body structure is reconstructed, resulting in a 3.49% reduction in mass, a 38.8% increase in bending stiffness, a 6.47% increase in torsional stiffness, and significantly enhanced collision safety performance.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141192065","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}
Mining dump truck is an important carrier used for short-distance round-trip transportation of ore and other materials in open-pit mines. This paper takes XDR80t mining dump truck produced by XCMG as the research object. The integrated virtual prototype model of hydro-pneumatic suspension mechanical and hydraulic systems is established by ADAMS and AMESim. The co-simulation environment is carried out to realize the virtual prototype modeling and simulation. Using the wheel and chassis centroid acceleration data collected at the site, a method based on frequency domain integration is proposed to calculate the displacement data which is used as the model input. Comparing the simulation test results with the field test results, both the errors of the suspension cylinder dynamic stroke and the body vertical acceleration root mean square (RMS) values are around 5%. The dynamic response of the vehicle body under typical road excitation at different vehicle speeds is analyzed by co-simulation. For low-speed obstacle crossings at 10 or 20 km/h, the original suspension system with only non-rod chamber interconnections system is able to ensure the ride comfort of the vehicle. While the speed is increased to 25 or 30 km/h, there will be a certain failure of the interconnecting suspension because of the poor fluid circulation condition, and the body vibration will be seriously aggravated. Therefore, the rod chamber of the cylinder is connected to guarantee the smooth flow of oil. The peak value of acceleration is reduced from 39.55 to 24.74 m/s2 at high speed, when the suspension was changed from a form with only non-rod chambers interconnected to both rod and non-rod chambers interconnected. When driving on random road, the RMS value of acceleration decreased by about 21.9%. This improved interconnected hydraulic system can effectively improve the ride comfort of the mining dump truck.
矿用自卸车是露天矿山短途往返运输矿石等物料的重要载体。本文以徐工集团生产的 XDR80t 矿用自卸车为研究对象。利用ADAMS和AMESim建立了液气悬架机械液压系统的集成虚拟样机模型。通过协同仿真环境实现虚拟样机的建模与仿真。利用现场采集的车轮和底盘中心点加速度数据，提出了一种基于频域积分的方法来计算位移数据，并将其作为模型输入。将仿真测试结果与现场测试结果进行比较，悬架油缸动态行程和车身垂直加速度均方根值的误差均在 5%左右。通过联合仿真分析了不同车速下典型路面激励下车身的动态响应。在以 10 或 20 km/h 的速度低速通过障碍物时，仅采用非杆腔互连系统的原始悬架系统能够确保车辆的乘坐舒适性。当车速提高到 25 或 30 km/h 时，由于流体循环状况不佳，互联悬架会出现一定的失效，车身振动会严重加剧。因此，为了保证油液的顺畅流动，油缸的杆腔是连通的。当悬架从只有非连杆室相通的形式变为连杆室和非连杆室都相通的形式时，高速行驶时的加速度峰值从 39.55 m/s2 降至 24.74 m/s2。在随机道路上行驶时，加速度均方根值降低了约 21.9%。改进后的互联液压系统可有效提高矿用自卸车的驾乘舒适性。
{"title":"Ride comfort analysis and optimization of a hydro-pneumatic suspension system for a mining dump truck","authors":"Qihang Liu, Xiumei Liu, Handui Feng, Beibei Li, Shen Liu, Yunlong Luo, Taiyang Sha","doi":"10.1177/09544070241251736","DOIUrl":"https://doi.org/10.1177/09544070241251736","url":null,"abstract":"Mining dump truck is an important carrier used for short-distance round-trip transportation of ore and other materials in open-pit mines. This paper takes XDR80t mining dump truck produced by XCMG as the research object. The integrated virtual prototype model of hydro-pneumatic suspension mechanical and hydraulic systems is established by ADAMS and AMESim. The co-simulation environment is carried out to realize the virtual prototype modeling and simulation. Using the wheel and chassis centroid acceleration data collected at the site, a method based on frequency domain integration is proposed to calculate the displacement data which is used as the model input. Comparing the simulation test results with the field test results, both the errors of the suspension cylinder dynamic stroke and the body vertical acceleration root mean square (RMS) values are around 5%. The dynamic response of the vehicle body under typical road excitation at different vehicle speeds is analyzed by co-simulation. For low-speed obstacle crossings at 10 or 20 km/h, the original suspension system with only non-rod chamber interconnections system is able to ensure the ride comfort of the vehicle. While the speed is increased to 25 or 30 km/h, there will be a certain failure of the interconnecting suspension because of the poor fluid circulation condition, and the body vibration will be seriously aggravated. Therefore, the rod chamber of the cylinder is connected to guarantee the smooth flow of oil. The peak value of acceleration is reduced from 39.55 to 24.74 m/s<jats:sup>2</jats:sup> at high speed, when the suspension was changed from a form with only non-rod chambers interconnected to both rod and non-rod chambers interconnected. When driving on random road, the RMS value of acceleration decreased by about 21.9%. This improved interconnected hydraulic system can effectively improve the ride comfort of the mining dump truck.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"85 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141191909","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 : 2024-05-30DOI: 10.1177/09544070241248872
Chaochun Yuan, Haichang Ji, Jie Shen, Long Chen, Yingfeng Cai, Youguo He, Shuofeng Weng, Yuqi Yuan
When intelligent vehicles encounter sudden and dangerous conditions, they often take the lateral lane change measure of emergency steering to avoid the risk, which can easily cause the vehicles to become unstable. In this paper, firstly the quintic polynomial is adopted as the lane change trajectory, the extreme lane change trajectory boundary is derived based on the dangerous phenomenon that vehicles are prone to sideslip and rollover, and the relationship between the road adhesion coefficient, longitudinal speed and the extreme lane change time is fitted. Then, based on the backstepping method and the dynamic surface control, a multi-constraint controller for sideslip angle of centroid and yaw rate is designed to regulate the steering of the vehicle by outputting additional yaw moment. The final simulation results show that the controller can have a good constraint effect under the extreme lane change, which ensures the accuracy of trajectory tracking and driving stability.
{"title":"Lateral stability control of extreme lane change based on dynamic surface and backstepping methods","authors":"Chaochun Yuan, Haichang Ji, Jie Shen, Long Chen, Yingfeng Cai, Youguo He, Shuofeng Weng, Yuqi Yuan","doi":"10.1177/09544070241248872","DOIUrl":"https://doi.org/10.1177/09544070241248872","url":null,"abstract":"When intelligent vehicles encounter sudden and dangerous conditions, they often take the lateral lane change measure of emergency steering to avoid the risk, which can easily cause the vehicles to become unstable. In this paper, firstly the quintic polynomial is adopted as the lane change trajectory, the extreme lane change trajectory boundary is derived based on the dangerous phenomenon that vehicles are prone to sideslip and rollover, and the relationship between the road adhesion coefficient, longitudinal speed and the extreme lane change time is fitted. Then, based on the backstepping method and the dynamic surface control, a multi-constraint controller for sideslip angle of centroid and yaw rate is designed to regulate the steering of the vehicle by outputting additional yaw moment. The final simulation results show that the controller can have a good constraint effect under the extreme lane change, which ensures the accuracy of trajectory tracking and driving stability.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"35 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141192100","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}
Owing to nonlinear issues such as external disturbances and uncertain parameters within the semi-active suspension system (SASS), the vibration amplitude of the suspension system tends to increase, and the time required for the suspension system to reach a steady-state response is prolonged. Hence, this paper proposes an adaptive backstepping control strategy based on radial basis function neural networks (RBF-NNs). Firstly, the damping force characteristics of the magnetorheological (MR) damper are tested, and the experimental data are utilized for parameters identification and fitting of the Bouc-Wen model. To establish a connection between the controller and the forward model of the MR damper, the forward model of the MR damper, the inverse model of the MR damper, and the model of the MR-SASS are constructed. Secondly, the backstepping controller and the adaptive backstepping controller based on RBF-NNs are designed. The stability and reliability of the closed-loop suspension system are verified through stability analysis using Lyapunov function. Finally, the dynamic characteristics of the passive control, backstepping control, and adaptive backstepping control strategies based on RBF-NNs applied to MR-SASS are analyzed under B-Class road excitation and speed bump road excitation. The acceleration, suspension dynamic deflection, and tire dynamic load are selected as the evaluation indices. The results demonstrate that the adaptive backstepping controller based on RBF-NNs significantly enhances the ride comfort of the SASS.
{"title":"An adaptive backstepping control strategy based on radial basis function neural networks for the magnetorheological semi-active suspension","authors":"Zeyu Pan, Xin Xiong, Jialing Chen, Lingfeng Zhang, Fei Xu, Bing Zhu","doi":"10.1177/09544070241252860","DOIUrl":"https://doi.org/10.1177/09544070241252860","url":null,"abstract":"Owing to nonlinear issues such as external disturbances and uncertain parameters within the semi-active suspension system (SASS), the vibration amplitude of the suspension system tends to increase, and the time required for the suspension system to reach a steady-state response is prolonged. Hence, this paper proposes an adaptive backstepping control strategy based on radial basis function neural networks (RBF-NNs). Firstly, the damping force characteristics of the magnetorheological (MR) damper are tested, and the experimental data are utilized for parameters identification and fitting of the Bouc-Wen model. To establish a connection between the controller and the forward model of the MR damper, the forward model of the MR damper, the inverse model of the MR damper, and the model of the MR-SASS are constructed. Secondly, the backstepping controller and the adaptive backstepping controller based on RBF-NNs are designed. The stability and reliability of the closed-loop suspension system are verified through stability analysis using Lyapunov function. Finally, the dynamic characteristics of the passive control, backstepping control, and adaptive backstepping control strategies based on RBF-NNs applied to MR-SASS are analyzed under B-Class road excitation and speed bump road excitation. The acceleration, suspension dynamic deflection, and tire dynamic load are selected as the evaluation indices. The results demonstrate that the adaptive backstepping controller based on RBF-NNs significantly enhances the ride comfort of the SASS.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"33 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141172625","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 : 2024-05-27DOI: 10.1177/09544070241245466
Xu Yang, Jun Ni
The self-reconfigurable ground vehicle (SRGV) has the ability of self-assembly and self-disassembly, which is a disruptive innovation to the traditional fixed configuration ground vehicle. The basic component of the SRGV is defined as a cell unit (CU), which is a complete system capable of working independently and has the basic function of the ground vehicle. The reconfiguration of the SRGV is not only the connection of the mechanical systems but also the integration between the power sources of different CUs. To this end, this paper proposes a novel multi-source parallel power system (MSPPS) for the SRGV, whose key characteristics are multi-branch and co-bus. The MSPPS can extend any number of power sources, which greatly improves the power level of SRGV. In this paper, the MSPPS with battery power source is discussed. The disassembly and assembly of the SRGV could lead to some inconsistencies such as SoC between the battery packs of each CU. To prolong the lifetime of the battery packs and working time of the SRGV, a hierarchical proportional control (HPC) strategy and a filtered model predictive control (FMPC) strategy are proposed. Both energy management strategies can reasonably allocate the output energy between different battery packs to meet the power demand and reduce battery inconsistencies. To verify and compare the effectiveness of the proposed two strategies, numerous simulations are carried out. The simulation results show that the FMPC strategy has faster convergence speed and lower power fluctuations in the energy management process. A SRGV prototype consisting of three CUs is developed, and the experimental platform for the power system of the SRGV is successfully established. The feasibility of the proposed MSPPS architecture is validated. The proposed HPC strategy is deployed in the rapid ECU. The experiment results are similar to the simulations and effectively demonstrate the real-time performance.
可自重构地面车辆（SRGV）具有自组装和自拆卸能力，是对传统固定构型地面车辆的颠覆性创新。SRGV 的基本组件被定义为单元（CU），它是一个能够独立工作的完整系统，具有地面车辆的基本功能。SRGV 的重新配置不仅包括机械系统的连接，还包括不同 CU 的动力源之间的整合。为此，本文为 SRGV 提出了一种新型多源并行电源系统（MSPPS），其主要特点是多分支和共总线。MSPPS 可以扩展任意数量的电源，从而大大提高了 SRGV 的功率水平。本文讨论了采用电池电源的 MSPPS。SRGV 的拆卸和组装可能会导致一些不一致性，例如每个 CU 的电池组之间的 SoC。为了延长电池组的使用寿命和 SRGV 的工作时间，提出了分层比例控制（HPC）策略和滤波模型预测控制（FMPC）策略。这两种能量管理策略都能在不同的电池组之间合理分配输出能量，以满足电力需求并减少电池的不一致性。为了验证和比较所提两种策略的有效性，我们进行了大量仿真。仿真结果表明，FMPC 策略收敛速度更快，能量管理过程中的功率波动更小。开发了由三个 CU 组成的 SRGV 原型，并成功建立了 SRGV 功率系统实验平台。验证了所提出的 MSPPS 架构的可行性。在快速 ECU 中部署了建议的 HPC 策略。实验结果与仿真结果相似，有效地证明了实时性能。
{"title":"The energy management strategy of the multi-source parallel power system for the self-reconfigurable ground vehicle","authors":"Xu Yang, Jun Ni","doi":"10.1177/09544070241245466","DOIUrl":"https://doi.org/10.1177/09544070241245466","url":null,"abstract":"The self-reconfigurable ground vehicle (SRGV) has the ability of self-assembly and self-disassembly, which is a disruptive innovation to the traditional fixed configuration ground vehicle. The basic component of the SRGV is defined as a cell unit (CU), which is a complete system capable of working independently and has the basic function of the ground vehicle. The reconfiguration of the SRGV is not only the connection of the mechanical systems but also the integration between the power sources of different CUs. To this end, this paper proposes a novel multi-source parallel power system (MSPPS) for the SRGV, whose key characteristics are multi-branch and co-bus. The MSPPS can extend any number of power sources, which greatly improves the power level of SRGV. In this paper, the MSPPS with battery power source is discussed. The disassembly and assembly of the SRGV could lead to some inconsistencies such as SoC between the battery packs of each CU. To prolong the lifetime of the battery packs and working time of the SRGV, a hierarchical proportional control (HPC) strategy and a filtered model predictive control (FMPC) strategy are proposed. Both energy management strategies can reasonably allocate the output energy between different battery packs to meet the power demand and reduce battery inconsistencies. To verify and compare the effectiveness of the proposed two strategies, numerous simulations are carried out. The simulation results show that the FMPC strategy has faster convergence speed and lower power fluctuations in the energy management process. A SRGV prototype consisting of three CUs is developed, and the experimental platform for the power system of the SRGV is successfully established. The feasibility of the proposed MSPPS architecture is validated. The proposed HPC strategy is deployed in the rapid ECU. The experiment results are similar to the simulations and effectively demonstrate the real-time performance.","PeriodicalId":54568,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part D-Journal of Automobile Engineering","volume":"39 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141172629","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}
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