Yucheng Liu, Andrew LeClair, Matthew Doude, Reuben F. Burch
A data acquisition system along with a sensor package was designed and installed on an existing mechanically-controlled cargo tractor to gather more data on their usage patterns. The data collected through the developed system include GPS route, vehicle speed and acceleration, engine state, transmission state, seat occupancy, fuel level, and video recording. The sensor package was designed and integrated in a way that does not interfere with the driver’s operation of the cargo tractor. Cellular network connectivity was employed to retrieve sensor data so as to minimize human effort and maintain typical usage patterns of the outfitted cargo tractors. Testing and validation results showed that the developed system can correctly and effectively record data necessary for further analysis and optimization. A fuel usage analysis was then completed using a chassis dynamometer based on the collected data. The collected data will significantly promote cargo tractor activity simulations in order to facilitate optimizing work flow at large industrial facilities and improving energy efficiency.
{"title":"Design, Installation, and Validation of a Data Acquisition System","authors":"Yucheng Liu, Andrew LeClair, Matthew Doude, Reuben F. Burch","doi":"10.1115/IMECE2018-87071","DOIUrl":"https://doi.org/10.1115/IMECE2018-87071","url":null,"abstract":"A data acquisition system along with a sensor package was designed and installed on an existing mechanically-controlled cargo tractor to gather more data on their usage patterns. The data collected through the developed system include GPS route, vehicle speed and acceleration, engine state, transmission state, seat occupancy, fuel level, and video recording. The sensor package was designed and integrated in a way that does not interfere with the driver’s operation of the cargo tractor. Cellular network connectivity was employed to retrieve sensor data so as to minimize human effort and maintain typical usage patterns of the outfitted cargo tractors. Testing and validation results showed that the developed system can correctly and effectively record data necessary for further analysis and optimization. A fuel usage analysis was then completed using a chassis dynamometer based on the collected data. The collected data will significantly promote cargo tractor activity simulations in order to facilitate optimizing work flow at large industrial facilities and improving energy efficiency.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125134679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In vehicle design modeling and simulation, surrogate model is commonly used to replace the high fidelity Finite Element (FE) model. A lot of simulation data from the high-fidelity FE model are utilized to construct an accurate surrogate model requires. However, computational time of FE model increases significantly with the growing complexities of vehicle engineering systems. In order to attain a surrogate model with satisfactory accuracy as well as acceptable computational time, this paper presents a model updated strategy based on multi-fidelity surrogate models. Based on a high-fidelity FE model and a low-fidelity FE model, an accurate multi-fidelity surrogate model is modeled. Firstly, the original full vehicle FE model is simplified to get a sub-model with acceptable accuracy, and it is able to capture the essential behaviors in the vehicle side impact simulations. Next, a primary response surface model (RSM) is built based on the simplified sub-model simulation data. Bayesian inference based bias term is modeled using the difference between the high-fidelity full vehicle FE model simulation data and the primary RSM running results. The bias is then incorporated to update the original RSM. This method can enhance the precision of surrogate model while saving computational time. A real-world side impact vehicle design case is utilized to demonstrate the validity of the proposed strategy.
{"title":"Research on a Multi-Fidelity Surrogate Model Based Model Updating Strategy","authors":"Ping Wang, Qingmiao Wang, Xin Yang, Zhenfei Zhan","doi":"10.1115/IMECE2018-88421","DOIUrl":"https://doi.org/10.1115/IMECE2018-88421","url":null,"abstract":"In vehicle design modeling and simulation, surrogate model is commonly used to replace the high fidelity Finite Element (FE) model. A lot of simulation data from the high-fidelity FE model are utilized to construct an accurate surrogate model requires. However, computational time of FE model increases significantly with the growing complexities of vehicle engineering systems. In order to attain a surrogate model with satisfactory accuracy as well as acceptable computational time, this paper presents a model updated strategy based on multi-fidelity surrogate models. Based on a high-fidelity FE model and a low-fidelity FE model, an accurate multi-fidelity surrogate model is modeled. Firstly, the original full vehicle FE model is simplified to get a sub-model with acceptable accuracy, and it is able to capture the essential behaviors in the vehicle side impact simulations. Next, a primary response surface model (RSM) is built based on the simplified sub-model simulation data. Bayesian inference based bias term is modeled using the difference between the high-fidelity full vehicle FE model simulation data and the primary RSM running results. The bias is then incorporated to update the original RSM. This method can enhance the precision of surrogate model while saving computational time. A real-world side impact vehicle design case is utilized to demonstrate the validity of the proposed strategy.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122735858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiaqi Zhao, Ming Zhang, Yu Zhu, Xin Li, Wang Leijie
The advanced development of additive manufacturing (AM) has greatly promoted the research and application of variable density porous structures. Meanwhile, AM constraints highlight the significance of design for AM (DFAM). The structural performance of existing topology optimization (TO) based design methods is limited and AM constraints are little considered. In this paper, we propose a novel optimization design method of AM oriented porous structures which allows the existence of void. A novel density filter is designed to achieve multi-interval TO for better structural performance and satisfy the minimum feature size constraint. Meanwhile, another customized density filter is designed to obtained support-free porous structure for the buildability constraint of AM. FEA results demonstrate that optimized porous structure designed by proposed method has better stiffness performance and adaptability to AM constraints, compared with existing methods.
{"title":"A Novel Optimization Design Method of Additive Manufacturing Oriented Porous Structures","authors":"Jiaqi Zhao, Ming Zhang, Yu Zhu, Xin Li, Wang Leijie","doi":"10.1115/IMECE2018-86952","DOIUrl":"https://doi.org/10.1115/IMECE2018-86952","url":null,"abstract":"The advanced development of additive manufacturing (AM) has greatly promoted the research and application of variable density porous structures. Meanwhile, AM constraints highlight the significance of design for AM (DFAM). The structural performance of existing topology optimization (TO) based design methods is limited and AM constraints are little considered. In this paper, we propose a novel optimization design method of AM oriented porous structures which allows the existence of void. A novel density filter is designed to achieve multi-interval TO for better structural performance and satisfy the minimum feature size constraint. Meanwhile, another customized density filter is designed to obtained support-free porous structure for the buildability constraint of AM. FEA results demonstrate that optimized porous structure designed by proposed method has better stiffness performance and adaptability to AM constraints, compared with existing methods.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131111429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The spindle system of machine tool produces a huge amounts of process data when it works. These data directly reflect the running state of spindle system but are seldom used to perform early fault warning. This paper proposes a novel early fault warning method adaptive weighted fuzzy Petri-net. Firstly, the long short-term memory (LSTM) is put forward to predict the time-series of future state for spindle system. Then, in order to design a reasoning framework for dynamic knowledge which can adapt to changes in the area of knowledge, an adaptive weighted fuzzy petri-net (AWFPN) is brought up to perform fault diagnosis. Finally, the effectiveness and feasibility of proposed method are verified by simulations and experiments. Results show that the proposed early fault warning method could effectively help to find potential fault information in the manufacturing process and provide the useful advice for maintenance.
{"title":"Early Fault Warning of Spindle Based on the Adaptive Weighted Fuzzy Petri Net","authors":"Hai Li, Wei Wang, Qingzhao Li, Lei Fan, Pu Huang","doi":"10.1115/IMECE2018-86042","DOIUrl":"https://doi.org/10.1115/IMECE2018-86042","url":null,"abstract":"The spindle system of machine tool produces a huge amounts of process data when it works. These data directly reflect the running state of spindle system but are seldom used to perform early fault warning. This paper proposes a novel early fault warning method adaptive weighted fuzzy Petri-net. Firstly, the long short-term memory (LSTM) is put forward to predict the time-series of future state for spindle system. Then, in order to design a reasoning framework for dynamic knowledge which can adapt to changes in the area of knowledge, an adaptive weighted fuzzy petri-net (AWFPN) is brought up to perform fault diagnosis. Finally, the effectiveness and feasibility of proposed method are verified by simulations and experiments. Results show that the proposed early fault warning method could effectively help to find potential fault information in the manufacturing process and provide the useful advice for maintenance.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115154554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Measurement of the reaction forces and moments (general wrench) are instrumental in the development stage of a product. Currently available measurement setups have varying ranges in different directions. The range of the device is limited to least stiff direction. The optimal use of load cell for predicted force/moment bounds is based on utilizing the system efficiently in different directions. We have presented a methodology to optimize the measurement setup based on directional stiffness behavior. The technique is coupled to design of load cell based on the characteristic structure of “Stewart platform”. The optimization function proposed allows the designer to design a measurement setup for a bound of the reaction force/moment. Additionally, the nonlinearities like friction and issue of loose joints due to relative motion at the passive joints are avoided. The improvement comes from replacement of the mechanical joints by kinematically constrained flexures.
{"title":"Optimal Reaction Wrench Measuring Platform","authors":"R. Kumar, A. Jain, J. P. Khatait","doi":"10.1115/IMECE2018-87057","DOIUrl":"https://doi.org/10.1115/IMECE2018-87057","url":null,"abstract":"Measurement of the reaction forces and moments (general wrench) are instrumental in the development stage of a product. Currently available measurement setups have varying ranges in different directions. The range of the device is limited to least stiff direction. The optimal use of load cell for predicted force/moment bounds is based on utilizing the system efficiently in different directions. We have presented a methodology to optimize the measurement setup based on directional stiffness behavior. The technique is coupled to design of load cell based on the characteristic structure of “Stewart platform”. The optimization function proposed allows the designer to design a measurement setup for a bound of the reaction force/moment. Additionally, the nonlinearities like friction and issue of loose joints due to relative motion at the passive joints are avoided. The improvement comes from replacement of the mechanical joints by kinematically constrained flexures.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133722411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Pourmostafaei, M. Pourgol-Mohammad, M. Yazdani, Hossein Salimi
In this paper, a new model is proposed for system degradation evaluation under sliding wear failure mechanism. This model estimates the material loss by progression of sliding distance. This model is generated by considering physical and geometrical aspects of system under wear mechanism. Several sets of experimental data are used for validation of the presented model. These experimental data are related to pin-on-disc test of Tungsten Carbide pins. These sets of data include initially conformal and non-conformal contacts. One set of data of pin-on-disc test by ASTM-G99 standard is used for additional validation of the model and for investigation of normal load effects on the parameters of presented model. Finally, uncertainty analysis is done by Monte-Carlo simulation to determine the variations of the predicted wear caused material loss.
{"title":"System Wear Life Estimation Under Uncertainty","authors":"Mohammad Pourmostafaei, M. Pourgol-Mohammad, M. Yazdani, Hossein Salimi","doi":"10.1115/IMECE2018-87015","DOIUrl":"https://doi.org/10.1115/IMECE2018-87015","url":null,"abstract":"In this paper, a new model is proposed for system degradation evaluation under sliding wear failure mechanism. This model estimates the material loss by progression of sliding distance. This model is generated by considering physical and geometrical aspects of system under wear mechanism. Several sets of experimental data are used for validation of the presented model. These experimental data are related to pin-on-disc test of Tungsten Carbide pins. These sets of data include initially conformal and non-conformal contacts. One set of data of pin-on-disc test by ASTM-G99 standard is used for additional validation of the model and for investigation of normal load effects on the parameters of presented model. Finally, uncertainty analysis is done by Monte-Carlo simulation to determine the variations of the predicted wear caused material loss.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117191440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human kind has always been intrigued by space but what seems to not make sense is why we aren’t just as intrigued about our ocean. As the life blood of all things on earth we need to understand the approximate 71% of water mass that surrounds us [1]. This is the goal of our paper, bringing interest back to the ocean using unmanned underwater vehicles. In this paper we will discuss the functionality, build and deployment of an intelligent unmanned drone. The mission of this underwater vehicle is to explore the ocean to understand complex ocean dynamics and bring forth the wonders of the ocean to the masses. We will systematically break down the design process of our drone circuitry and sensors on board, then see why we chose these components and sensors to successfully achieve our objective of collecting targeted data from the ocean.
{"title":"Unmanned Underwater Drone Design for Ocean Exploration","authors":"R. Goonesekere, Yu Guo","doi":"10.1115/IMECE2018-87649","DOIUrl":"https://doi.org/10.1115/IMECE2018-87649","url":null,"abstract":"Human kind has always been intrigued by space but what seems to not make sense is why we aren’t just as intrigued about our ocean. As the life blood of all things on earth we need to understand the approximate 71% of water mass that surrounds us [1]. This is the goal of our paper, bringing interest back to the ocean using unmanned underwater vehicles. In this paper we will discuss the functionality, build and deployment of an intelligent unmanned drone. The mission of this underwater vehicle is to explore the ocean to understand complex ocean dynamics and bring forth the wonders of the ocean to the masses. We will systematically break down the design process of our drone circuitry and sensors on board, then see why we chose these components and sensors to successfully achieve our objective of collecting targeted data from the ocean.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128576296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Hybrid-III Rail Safety (H3-RS) anthropomorphic test device (ATD), also known as a crash test dummy, was developed by the Rail Safety and Standards Board (RSSB), DeltaRail (now Resonate Group Ltd.), and the Transport Research Laboratory (TRL) in the United Kingdom between 2002 and 2005 for passenger rail safety applications [1]. The H3-RS is a modification of the standard Hybrid-III 50th percentile male (H3-50M) ATD with additional features in the chest and abdomen to increase its biofidelity and eight sensors to measure deflection. The H3-RS features bilateral (left and right) deflection sensors in the upper and lower chest and in the upper and lower abdomen; whereas, the standard H3-50M only features a single unilateral (center) deflection sensor in the chest with no deflection sensors located in the abdomen. Additional H3-RS research was performed by the Volpe National Transportation Systems Center (Volpe Center) under the direction of the U.S. Department of Transportation, Federal Railroad Administration (FRA) Office of Research, Development, and Technology. The Volpe Center contracted with TRL to conduct a series of dynamic pendulum impact tests [2]. The goal of testing the abdomen response of the H3-RS ATD was to develop data to refine an abdomen design that produces biofidelic and repeatable results under various impact conditions with respect to impactor geometry, vertical impact height, and velocity. In this study, the abdominal response of the H3-RS finite element (FE) model that TRL developed is validated using the results from pendulum impact tests [2]. Results from the pendulum impact tests and corresponding H3-RS FE simulations are compared using the longitudinal relative deflection measurements from the internal sensors in the chest and abdomen as well as the longitudinal accelerometer readings from the impactor. The abdominal response of the H3-RS FE model correlated well with the physical ATD as the impactor geometry, vertical impact height, and velocity were changed. There were limitations with lumbar positioning of the H3-RS FE model as well as the material definition for the relaxation rate of the foam in the abdomen that can be improved in future work. The main goal of validating the abdominal response of the dummy model is to enable its use in assessing injury potential in dynamic sled testing of crashworthy workstation tables, the results of which are presented in a companion paper [3]. The authors used the model of the H3-RS ATD to study the 8G sled test specified in the American Public Transportation Association (APTA) workstation table safety standard [4]. The 8G sled test is intended to simulate the longitudinal crash accleration in a severe train-to-train collision involving U.S. passenger equipment. Analyses of the dynamic sled test are useful for studying the sensitivity of the sled test to factors such as table height, table force-crush behavior, seat pitch, etc., which help to inform discussions on revisions
{"title":"Finite Element Model Validation of the Hybrid-III Rail Safety (H3-RS) Anthropomorphic Test Device (ATD)","authors":"Shaun Eshraghi, K. Severson, D. Hynd, A. Perlman","doi":"10.1115/IMECE2018-87736","DOIUrl":"https://doi.org/10.1115/IMECE2018-87736","url":null,"abstract":"The Hybrid-III Rail Safety (H3-RS) anthropomorphic test device (ATD), also known as a crash test dummy, was developed by the Rail Safety and Standards Board (RSSB), DeltaRail (now Resonate Group Ltd.), and the Transport Research Laboratory (TRL) in the United Kingdom between 2002 and 2005 for passenger rail safety applications [1]. The H3-RS is a modification of the standard Hybrid-III 50th percentile male (H3-50M) ATD with additional features in the chest and abdomen to increase its biofidelity and eight sensors to measure deflection. The H3-RS features bilateral (left and right) deflection sensors in the upper and lower chest and in the upper and lower abdomen; whereas, the standard H3-50M only features a single unilateral (center) deflection sensor in the chest with no deflection sensors located in the abdomen.\u0000 Additional H3-RS research was performed by the Volpe National Transportation Systems Center (Volpe Center) under the direction of the U.S. Department of Transportation, Federal Railroad Administration (FRA) Office of Research, Development, and Technology. The Volpe Center contracted with TRL to conduct a series of dynamic pendulum impact tests [2]. The goal of testing the abdomen response of the H3-RS ATD was to develop data to refine an abdomen design that produces biofidelic and repeatable results under various impact conditions with respect to impactor geometry, vertical impact height, and velocity.\u0000 In this study, the abdominal response of the H3-RS finite element (FE) model that TRL developed is validated using the results from pendulum impact tests [2]. Results from the pendulum impact tests and corresponding H3-RS FE simulations are compared using the longitudinal relative deflection measurements from the internal sensors in the chest and abdomen as well as the longitudinal accelerometer readings from the impactor. The abdominal response of the H3-RS FE model correlated well with the physical ATD as the impactor geometry, vertical impact height, and velocity were changed. There were limitations with lumbar positioning of the H3-RS FE model as well as the material definition for the relaxation rate of the foam in the abdomen that can be improved in future work.\u0000 The main goal of validating the abdominal response of the dummy model is to enable its use in assessing injury potential in dynamic sled testing of crashworthy workstation tables, the results of which are presented in a companion paper [3]. The authors used the model of the H3-RS ATD to study the 8G sled test specified in the American Public Transportation Association (APTA) workstation table safety standard [4]. The 8G sled test is intended to simulate the longitudinal crash accleration in a severe train-to-train collision involving U.S. passenger equipment. Analyses of the dynamic sled test are useful for studying the sensitivity of the sled test to factors such as table height, table force-crush behavior, seat pitch, etc., which help to inform discussions on revisions ","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127565161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Contero, Ferran Naya, David Pérez-López, Pedro Company, J. Camba
Design reusability largely depends on the parametric quality of its associated digital product data. In this regard, the quality of the master model (typically a history-based parametric model) is crucial. However, no quantitative metrics exist that can provide an accurate assessment of parametric complexity and model reusability. In this paper, a set of 370 parametric 3D CAD models of various geometric complexities were analyzed to assess their robustness when undergoing alteration. Three indicators for estimating the modification ability of the model are proposed: Ratio for Exhaustive Modification, Ratio for Selective Exhaustive Modification, and Ratio for Weighted Exhaustive Modification. Correlations between these indicators as well as other geometric complexity metrics are studied. The geometric complexity metrics considered in our study include number of faces, surface area to volume ratio, sphericity, and convexity. Our experimental results with the proposed indicators provide new insights on the quantitative assessment of parametric complexity and support their use as reliable indicators of CAD model reusability.
{"title":"A Study on Sampling Strategies to Determine the Variability of Parametric History-Based 3D CAD Models","authors":"M. Contero, Ferran Naya, David Pérez-López, Pedro Company, J. Camba","doi":"10.1115/IMECE2018-87404","DOIUrl":"https://doi.org/10.1115/IMECE2018-87404","url":null,"abstract":"Design reusability largely depends on the parametric quality of its associated digital product data. In this regard, the quality of the master model (typically a history-based parametric model) is crucial. However, no quantitative metrics exist that can provide an accurate assessment of parametric complexity and model reusability. In this paper, a set of 370 parametric 3D CAD models of various geometric complexities were analyzed to assess their robustness when undergoing alteration. Three indicators for estimating the modification ability of the model are proposed: Ratio for Exhaustive Modification, Ratio for Selective Exhaustive Modification, and Ratio for Weighted Exhaustive Modification. Correlations between these indicators as well as other geometric complexity metrics are studied. The geometric complexity metrics considered in our study include number of faces, surface area to volume ratio, sphericity, and convexity. Our experimental results with the proposed indicators provide new insights on the quantitative assessment of parametric complexity and support their use as reliable indicators of CAD model reusability.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126826309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The U.S. Department of Transportation (DOT) Federal Railroad Administration (FRA) began promulgating regulations for the structural crashworthiness of passenger rail equipment at 49 Code of Federal Regulations (CFR) Part 238 on May 12, 1999. These Passenger Equipment Safety Standards (PESS) [1] include requirements affecting the designs of sidewall structures on passenger rail equipment. The FRA’s Office of Research, Development and Technology and the DOT’s Volpe National Transportation Systems Center are conducting research to evaluate the side impact strength of Tier I passenger rail equipment designs that have been constructed according to the current side structure regulations in §238.215 and §238.217. Following a fatal 2011 accident in which a highway semitrailer truck impacted the side of a passenger train that was transiting a grade crossing in Miriam, NV, the National Transportation Safety Board (NTSB) recommended that the FRA “develop side impact crashworthiness standards (including performance validation) for passenger railcars that provide a measurable improvement compared to the current regulation for minimizing encroachment to and loss of railcar occupant survival space” [2]. This paper describes the status of the current FRA research related to side structure integrity and describes the planned next stage of the research program which will include analyzing the performance of generalized passenger railcar structures in side impact collision scenarios. A discussion of the technical challenges associated with analyzing side impacts on passenger rail equipment is also presented.
{"title":"Side Structure Integrity Research for Passenger Rail Equipment","authors":"Shaun Eshraghi, Michael Carolan, A. Perlman","doi":"10.1115/IMECE2018-87700","DOIUrl":"https://doi.org/10.1115/IMECE2018-87700","url":null,"abstract":"The U.S. Department of Transportation (DOT) Federal Railroad Administration (FRA) began promulgating regulations for the structural crashworthiness of passenger rail equipment at 49 Code of Federal Regulations (CFR) Part 238 on May 12, 1999. These Passenger Equipment Safety Standards (PESS) [1] include requirements affecting the designs of sidewall structures on passenger rail equipment. The FRA’s Office of Research, Development and Technology and the DOT’s Volpe National Transportation Systems Center are conducting research to evaluate the side impact strength of Tier I passenger rail equipment designs that have been constructed according to the current side structure regulations in §238.215 and §238.217.\u0000 Following a fatal 2011 accident in which a highway semitrailer truck impacted the side of a passenger train that was transiting a grade crossing in Miriam, NV, the National Transportation Safety Board (NTSB) recommended that the FRA “develop side impact crashworthiness standards (including performance validation) for passenger railcars that provide a measurable improvement compared to the current regulation for minimizing encroachment to and loss of railcar occupant survival space” [2].\u0000 This paper describes the status of the current FRA research related to side structure integrity and describes the planned next stage of the research program which will include analyzing the performance of generalized passenger railcar structures in side impact collision scenarios. A discussion of the technical challenges associated with analyzing side impacts on passenger rail equipment is also presented.","PeriodicalId":201128,"journal":{"name":"Volume 13: Design, Reliability, Safety, and Risk","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114209049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：