The scope of the paper is the design of a fluid machinery with a multiphysics procedure, through CAD （computer-aided design）-CAE （computer-aided engineering）-CAx （computer-aided technologies） tools. The study of...The scope of the paper is the design of a fluid machinery with a multiphysics procedure, through CAD （computer-aided design）-CAE （computer-aided engineering）-CAx （computer-aided technologies） tools. The study of a wind turbine is a perfect example of a project that requires an interdisciplinary team design, in fact for such a project mechanical structure, and CFD （computational fluid dynamics） designers are necessary. In addition, in the last years, the multi domain design has been supported by the continuous development of software for computer-aided design and the unceasing increase of the connection between performances and computer costs： the final aim is to propose the instruments that assist the designer throughout all the steps of the project. The multi domain design, illustrated in this article, is based on how to design the wind turbine, and it is not about process management and manufacturability. In particular, in the article, the emphasis will be placed on the integration between CAD and mathematical software of general type and on the CAD-CAE integration.展开更多
A novel method of incorporating generalized predictive control GPC algorithms based on quantitative feedback theory QFT principles is proposed for solving the feedback control problem of the highly uncertain and cross...A novel method of incorporating generalized predictive control GPC algorithms based on quantitative feedback theory QFT principles is proposed for solving the feedback control problem of the highly uncertain and cross-coupling plants. The quantitative feedback theory decouples the multi-input and multi-output MIMO plant and is also used to reduce the uncertainties of the system, stabilize the system, and achieve tracking performance of the system to a certain extent. Single-input and single-output SISO generalized predictive control is used to achieve performance with higher performance. In GPC, the model is identified on-line, which is based on the QFT input and the plant output signals. The simulation results show that the performance of the system is superior to the performance when only QFT is used for highly uncertain MIMO plants.展开更多
With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deploy...With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deployment of level 5 full automated vehicles,the physical infrastructure is required to maintain a fundamental role to enable their introduction in public roads.This paper focuses on lane support system(LSS)whose operational design domain(ODD)is strongly connected to the road characteristics and conditions.An experimental test was carried out with a state of the art,and LSS and advanced technologies were used for road monitoring on different roads under various environmental conditions including dry,wet pavements and rain.We applied the generalized estimation equation for logistic regression to account within-cluster homogeneity which is induced by repeated measures on the same road sections.Statistical models allow the identification of variables that are significant for the LSS fault probability among various effects of road features including marking,pavement distress,weather conditions,horizontal curvature,and cross section.Results pointed out the relevance of the wet retro-reflection of marking(RLw)and the horizontal curvature in the definition of ODD for LSS.Threshold values have been proposed for the tested LSS.Wet pavement doesn’t affect the LSS performance when compared to the dry condition.Rain was shown to be critical even with very good road characteristics.展开更多
This paper investigates the machine detectability(MD)of road markings under various environmental conditions,crucial for the definition of operational design domains(ODD)of automated driving systems as well as the ass...This paper investigates the machine detectability(MD)of road markings under various environmental conditions,crucial for the definition of operational design domains(ODD)of automated driving systems as well as the assessment of operational domains(OD).By analysing the correlation between MD parameters,specifically contrast,gradient,and edge detectability,and common photometric properties of road markings currently used for maintenance management(retroreflectivity and daytime visibility),the paper aims to bridge the gap in current road marking detectability research and OD assessment.The methodology encompassed a detailed examination of road markings on a motorway under different lighting and weather conditions,employing both camera and Li DAR sensors for data collection.The findings reveal that the retroreflectivity is a consistent predictor for MD in camera images during nighttime and for Li DAR contrast in dry and moist conditions,whereas the daytime visibility fails to reliably predict MD in daytime conditions.Moreover,the study introduces a multi-parameter approach that transcends sole contrast analysis as well as the usage of off-the-shelf machine vision systems,proposing a new set of MD parameters for a broader and transparent evaluation of road marking detectability.This comprehensive assessment highlights the need for quality standards for road markings that would accommodate varying environmental impacts on MD of road markings.Ultimately,this research provides valuable insights and recommendations on research approaches to find demand-oriented minimum standards for MD of road markings,enabling comprehensive OD assessments,and facilitating safer navigation for automated vehicles.展开更多
Bioinspired soft robots hold great potential to perform tasks in unstructured terrains.Ferroelectric polymers are highly valued in soft robots for their flexibility,lightweight,and electrically controllable deformatio...Bioinspired soft robots hold great potential to perform tasks in unstructured terrains.Ferroelectric polymers are highly valued in soft robots for their flexibility,lightweight,and electrically controllable deformation.However,achieving large strains in ferroelectric polymers typically requires high driving voltages,posing a significant challenge for practical applications.In this study,we investigate the role of crystalline domain size in enhancing the electrostrain performance of the relaxor ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene-fluorinated alkynes)(P(VDFTrFE-CFE-FA)).Leveraging its remarkable inverse piezoelectric coefficient(|d33^(*)|=701 pm V^(-1)),we demonstrate that the planar films exhibit a five times larger bending angle than that of commercial PVDF films at low electric fields.Based on this material,we design a petal-structured soft robot that achieves a curvature of up to 4.5 cm^(-1) at a DC electric field of 30 Vμm^(-1).When integrated into a bipedal soft robot,it manifests outstanding electrostrain performance,achieving rapid locomotion of~19 body lengths per second(BL s^(-1))at 10 Vμm^(-1)(560 Hz).Moreover,the developed robot demonstrates remarkable abilities in climbing slopes and carrying heavy loads.These findings open new avenues for developing low-voltage-driven soft robots with significant promise for practical applications.展开更多
Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundari...Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.Design/methodology/approach–A unified model of ODD monitoring is constructed,which consists of three modules:weather condition monitoring for unusual weather conditions,such as rain,snow and fog;vehicle behavior monitoring for abnormal vehicle behavior,such as traffic rule violations;and road condition monitoring for abnormal road conditions,such as road defects,unexpected obstacles and slippery roads.Additionally,the applications of the proposed unified ODD monitoring framework are demonstrated.The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.Findings–First,the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework.Second,the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework.Third,the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.Originality/value–The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.展开更多
文摘The scope of the paper is the design of a fluid machinery with a multiphysics procedure, through CAD （computer-aided design）-CAE （computer-aided engineering）-CAx （computer-aided technologies） tools. The study of a wind turbine is a perfect example of a project that requires an interdisciplinary team design, in fact for such a project mechanical structure, and CFD （computational fluid dynamics） designers are necessary. In addition, in the last years, the multi domain design has been supported by the continuous development of software for computer-aided design and the unceasing increase of the connection between performances and computer costs： the final aim is to propose the instruments that assist the designer throughout all the steps of the project. The multi domain design, illustrated in this article, is based on how to design the wind turbine, and it is not about process management and manufacturability. In particular, in the article, the emphasis will be placed on the integration between CAD and mathematical software of general type and on the CAD-CAE integration.
基金the National Natural Science Foundation of China (No.60374037, No.60574036)the Program for New CenturyExcellent Talents in Education Ministry (NCET)the Specialized Research Fund for the Doctoral Program of Higher Edu-cation of China (No.20050055013)
文摘A novel method of incorporating generalized predictive control GPC algorithms based on quantitative feedback theory QFT principles is proposed for solving the feedback control problem of the highly uncertain and cross-coupling plants. The quantitative feedback theory decouples the multi-input and multi-output MIMO plant and is also used to reduce the uncertainties of the system, stabilize the system, and achieve tracking performance of the system to a certain extent. Single-input and single-output SISO generalized predictive control is used to achieve performance with higher performance. In GPC, the model is identified on-line, which is based on the QFT input and the plant output signals. The simulation results show that the performance of the system is superior to the performance when only QFT is used for highly uncertain MIMO plants.
基金partially financed by“Astro Database”Project of the University of Catania
文摘With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deployment of level 5 full automated vehicles,the physical infrastructure is required to maintain a fundamental role to enable their introduction in public roads.This paper focuses on lane support system(LSS)whose operational design domain(ODD)is strongly connected to the road characteristics and conditions.An experimental test was carried out with a state of the art,and LSS and advanced technologies were used for road monitoring on different roads under various environmental conditions including dry,wet pavements and rain.We applied the generalized estimation equation for logistic regression to account within-cluster homogeneity which is induced by repeated measures on the same road sections.Statistical models allow the identification of variables that are significant for the LSS fault probability among various effects of road features including marking,pavement distress,weather conditions,horizontal curvature,and cross section.Results pointed out the relevance of the wet retro-reflection of marking(RLw)and the horizontal curvature in the definition of ODD for LSS.Threshold values have been proposed for the tested LSS.Wet pavement doesn’t affect the LSS performance when compared to the dry condition.Rain was shown to be critical even with very good road characteristics.
基金the German Federal Highway Research Institute(BASt)project FE 0.3.0590/2019/EGB,which funded part of the measurements in this study。
文摘This paper investigates the machine detectability(MD)of road markings under various environmental conditions,crucial for the definition of operational design domains(ODD)of automated driving systems as well as the assessment of operational domains(OD).By analysing the correlation between MD parameters,specifically contrast,gradient,and edge detectability,and common photometric properties of road markings currently used for maintenance management(retroreflectivity and daytime visibility),the paper aims to bridge the gap in current road marking detectability research and OD assessment.The methodology encompassed a detailed examination of road markings on a motorway under different lighting and weather conditions,employing both camera and Li DAR sensors for data collection.The findings reveal that the retroreflectivity is a consistent predictor for MD in camera images during nighttime and for Li DAR contrast in dry and moist conditions,whereas the daytime visibility fails to reliably predict MD in daytime conditions.Moreover,the study introduces a multi-parameter approach that transcends sole contrast analysis as well as the usage of off-the-shelf machine vision systems,proposing a new set of MD parameters for a broader and transparent evaluation of road marking detectability.This comprehensive assessment highlights the need for quality standards for road markings that would accommodate varying environmental impacts on MD of road markings.Ultimately,this research provides valuable insights and recommendations on research approaches to find demand-oriented minimum standards for MD of road markings,enabling comprehensive OD assessments,and facilitating safer navigation for automated vehicles.
基金National Natural Science Foundation of China,Grant/Award Number:U2330120Natural Science Foundation of Sichuan Province of China,Grant/Award Number:2023NSFSC0313Basic Research Cultivation Project of Southwest Jiaotong University,Grant/Award Number:2682023KJ024。
文摘Bioinspired soft robots hold great potential to perform tasks in unstructured terrains.Ferroelectric polymers are highly valued in soft robots for their flexibility,lightweight,and electrically controllable deformation.However,achieving large strains in ferroelectric polymers typically requires high driving voltages,posing a significant challenge for practical applications.In this study,we investigate the role of crystalline domain size in enhancing the electrostrain performance of the relaxor ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene-fluorinated alkynes)(P(VDFTrFE-CFE-FA)).Leveraging its remarkable inverse piezoelectric coefficient(|d33^(*)|=701 pm V^(-1)),we demonstrate that the planar films exhibit a five times larger bending angle than that of commercial PVDF films at low electric fields.Based on this material,we design a petal-structured soft robot that achieves a curvature of up to 4.5 cm^(-1) at a DC electric field of 30 Vμm^(-1).When integrated into a bipedal soft robot,it manifests outstanding electrostrain performance,achieving rapid locomotion of~19 body lengths per second(BL s^(-1))at 10 Vμm^(-1)(560 Hz).Moreover,the developed robot demonstrates remarkable abilities in climbing slopes and carrying heavy loads.These findings open new avenues for developing low-voltage-driven soft robots with significant promise for practical applications.
基金the financial support of the National Key R&D Program of China(Grant No.2020YFB1600303)the National Science Foundation of China Project:(Grant Nos.U1964203 and 52072215).
文摘Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.Design/methodology/approach–A unified model of ODD monitoring is constructed,which consists of three modules:weather condition monitoring for unusual weather conditions,such as rain,snow and fog;vehicle behavior monitoring for abnormal vehicle behavior,such as traffic rule violations;and road condition monitoring for abnormal road conditions,such as road defects,unexpected obstacles and slippery roads.Additionally,the applications of the proposed unified ODD monitoring framework are demonstrated.The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.Findings–First,the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework.Second,the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework.Third,the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.Originality/value–The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.
