Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase...Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving.展开更多
The extended Kalman filter (EKF) algorithm and acceleration sensor measurements were used to identify vehiclemass and road gradient in the work. Four different states of fixed mass, variable mass, fixed slope and vari...The extended Kalman filter (EKF) algorithm and acceleration sensor measurements were used to identify vehiclemass and road gradient in the work. Four different states of fixed mass, variable mass, fixed slope and variableslope were set to simulate real-time working conditions, respectively. A comprehensive electric commercial vehicleshifting strategy was formulated according to the identification results. The co-simulation results showed that,compared with the recursive least square (RLS) algorithm, the proposed algorithm could identify the real-timevehicle mass and road gradient quickly and accurately. The comprehensive shifting strategy formulated had thefollowing advantages, e.g., avoiding frequent shifting of vehicles up the hill, making full use ofmotor braking downthe hill, and improving the overall performance of vehicles.展开更多
The reduction of fuel consumption in engines is always considered of vital importance.Along these lines,in this work,this goal was attained by optimizing the heavy-duty commercial vehicle engine control strategy.More ...The reduction of fuel consumption in engines is always considered of vital importance.Along these lines,in this work,this goal was attained by optimizing the heavy-duty commercial vehicle engine control strategy.More specifically,at first,a general first principles model for heavy-duty commercial vehicles and a transient fuel consumptionmodel for heavy-duty commercial vehicles were developed and the parameters were adjusted to fit the empirical data.The accuracy of the proposed modelwas demonstrated fromthe stage and the final results.Next,the control optimization problem resulting in low fuel consumption in heavy commercial vehicles was described,with minimal fuel usage as the optimization goal and throttle opening as the control variable.Then,a time-continuous engine management approach was assessed.Next,the factors that influence low fuel consumption in heavy-duty commercial vehicles were systematically examined.To reduce the computing complexity,the control strategies related to the time constraints of the engine were parametrized using three different methods.The most effective solution was obtained by applying a global optimization strategy because the constrained optimization problem was nonlinear.Finally,the effectiveness of the low-fuel consumption engine control strategy was demonstrated by comparing the simulated and field test results.展开更多
今年IAA的口号“Driven by Ideas'(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。今年IAA的口号“Driven by Ideas”(创意驱动)在这场全球最重要的交通、物...今年IAA的口号“Driven by Ideas'(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。今年IAA的口号“Driven by Ideas”(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。整个商用车行业向IAA观众展示了创新、创造力和先锋精神。这些品质表现在332款产品的全球首发和1 00多款产品的欧洲首发。此次IAA更是决策者的贸易展,并且国际化程度前所未有。展开更多
Fire incidents in commercial vehicles pose significant risks to passengers, drivers, and cargo. Traditional fire extinguishing systems, while effective, may have limitations in terms of response time, coverage, and hu...Fire incidents in commercial vehicles pose significant risks to passengers, drivers, and cargo. Traditional fire extinguishing systems, while effective, may have limitations in terms of response time, coverage, and human intervention [1]. This study investigates the efficacy of a novel fire suppression technology—the Exploding Fire Extinguishing Ball (EFEB) —as an alternative and complementary fire safety solution for commercial vehicles. The research employs a multidisciplinary approach, encompassing engineering, materials science, fire safety, and human factors analysis. A systematic literature review establishes a comprehensive understanding of existing fire suppression technologies, including EFEBs. Subsequently, this study analyzes the unique features of EFEBs, such as automatic activation, as well as manual activation upon exposure to fire, and their potential to provide rapid, localized, and autonomous fire suppression. The study presents original experimental investigations to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. Experiments include controlled fires in confined spaces and dynamic simulations to emulate real-world fire incidents. Data on activation times, extinguishing capability, and coverage area are collected and analyzed to compare the efficacy of EFEBs with traditional fire extinguishing methods. Furthermore, this research shows the practical aspects of implementing EFEBs in commercial vehicles. A feasibility study examines the integration challenges, cost-benefit analysis, and potential regulatory implications. The study also addresses the impact of EFEBs on vehicle weight, stability, and overall safety. Human factors and user acceptance are crucial elements in adopting new safety technologies. Therefore, this research utilizes an experimental design to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. This dissertation presents original controlled experiments to emulate real-world fire incidents, including controlled fires in confined spaces and dynamic simulations. The experimental approach ensures rigorous evaluation and objective insights into EFEBs’ potential as an autonomous fire suppression system for commercial vehicles. This includes the perspectives of drivers, passengers, fleet operators, insurance agencies, and regulatory bodies. Factors influencing trust, perceived safety, and willingness to adopt EFEBs are analyzed to provide insights into the successful integration of this technology. The findings of this research will contribute to the knowledge of fire safety technology and expand the understanding of the applicability of EFEBs in commercial vehicles.展开更多
New and increasingly sharp laws for the reduction of emissions from commercial vehicles entered into force in the European Union since 1993 with the aim of substan-tially reducing pollutants and emissions from trucks ...New and increasingly sharp laws for the reduction of emissions from commercial vehicles entered into force in the European Union since 1993 with the aim of substan-tially reducing pollutants and emissions from trucks and buses. Thereby the maximum levels for the emission of particulate matter (basically soot particles) as well as oxides of nitrogen (NOx) have been subsequently lowered. To comply with these demands, commercial vehicle producers had to introduce new emission reducing technologies of which exhaust-gas recirculation (EGR),展开更多
Improved manufacturing technology is often needed when working with high strength steel. In this re- spect manufacturing technology has to adapt to the altered (and typically reduced) formability and weldability of ...Improved manufacturing technology is often needed when working with high strength steel. In this re- spect manufacturing technology has to adapt to the altered (and typically reduced) formability and weldability of modern high strength steel. However, this is a rather passive approach from a manufacturing point of view. An indeed much more powerful approach is to generate synergies between innovative manufacturing technology, design and material enabling additional weight savings and efficiency gains. Laser-based material processing, in particular laser welding, offers a wide range of opportunities in this sense. Furthermore, hot stamping and roll forming open up new possibilities for advanced manufacturing of commercial vehicle components. Applications and examples of these technologies will be given in terms of producing innovative semi-products as well as final components.展开更多
Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China's energy supply and environment. Thus sustainable devel...Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China's energy supply and environment. Thus sustainable development of the Chinese automotive industry must pay significant attention to fuel-saving and emission-reduction of vehicles. Although commercial vehicles make up only about 20% of the entire automobile fleet, their contribution to energy-consumption and emission of pollutants is significant. Thus, priority should be given to fuel-saving and emission-reduction of commercial vehicles. As a result of concerted efforts by Chinese government, industry and enterprises, great progress has been made in technologies concerning new-energy, intelligent and lightweight auto- mobiles. However, compared with developed countries, the level of lightweighting of commercial vehicles produced in China remains comparably low. This means that great potential for development of lightweight commercial vehicles in China exists and it will be an efficient path towards fuel-saving and emission-reduction.展开更多
1. An overall judgment on the situation 2006 saw the rapid growth of passenger vehicles, with the production capacity putting into use rose from less than 70 percent to around 80 percent. That with light commercial ve...1. An overall judgment on the situation 2006 saw the rapid growth of passenger vehicles, with the production capacity putting into use rose from less than 70 percent to around 80 percent. That with light commercial vehicles was similar too. The situation in 2005 and 2006 showed that there are no evidential overdone production capacity.展开更多
When heavy-duty commercial vehicles(HDCVs)must engage in emergency braking,uncertain conditions such as the brake pressure and road profile variations will inevitably affect braking control.To minimize these uncertain...When heavy-duty commercial vehicles(HDCVs)must engage in emergency braking,uncertain conditions such as the brake pressure and road profile variations will inevitably affect braking control.To minimize these uncertainties,we propose a combined longitudinal and lateral controller method based on stochastic model predictive control(SMPC)that is achieved via Chebyshev–Cantelli inequality.In our method,SMPC calculates braking control inputs based on a finite time prediction that is achieved by solving stochastic programming elements,including chance constraints.To accomplish this,SMPC explicitly describes the probabilistic uncertainties to be used when designing a robust control strategy.The main contribution of this paper is the proposal of a braking control formulation that is robust against probabilistic friction circle uncertainty effects.More specifically,the use of Chebyshev–Cantelli inequality suppresses road profile influences,which have characteristics that are different from the Gaussian distribution,thereby improving both braking robustness and control performance against statistical disturbances.Additionally,since the Kalman filtering(KF)algorithm is used to obtain the expectation and covariance used for calculating deterministic transformed chance constraints,the SMPC is reformulated as a KF embedded deterministic MPC.Herein,the effectiveness of our proposed method is verified via a MATLAB/Simulink and TruckSim co-simulation.展开更多
The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by aroun...The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by around 10.15% annually and the sales of medium and heavy trucks by around 18.87% (sales increased from 0.2 million in 2000 to 1.3 million in 2010) according to the National Bureau of Statistics of People's Republic of China. Today commercial vehicles consume almost the same amount of fuel as pas- senger cars in China although the number of commercial vehicles is only about one fourth of passenger cars. It is estimated that around 50% of imported fuel to China each year will be consumed by vehicle transportation. This si- tuation will worsen fuel shortage problems in the long run and at the same time it is partially responsible for the ever- worsening air pollution in China. Due to the widespread overloading in China, lightweight development in commer- cial vehicles has fallen far behind that of passenger cars with the consequences that Chinese commercial vehicles consume in average about 20% more fuel, especially the heavy trucks, compared to European models. Under these circumstances it is essential to reduce the vehicle fuel consumption and in- crease the transport efficiency. The key solution thereby is to implement lightweight design in commercial vehicles as it has been successfully practiced over the last decade in the passenger cars. This paper summarizes highlights given in presentations during the "International seminar on the ap- plication of high strength steels in light weight commercial vehicles" with the focus on the development and application of Nb alloyed high performance steels made for lightweight commercial vehicles.展开更多
Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck s...Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.展开更多
Latest data from the China Association of Automobile Manufacturers(CAAM) shows that through 2010.China’s automobile sales surpassed 18 million, breaking the world record of annual auto sales previously held by the Un...Latest data from the China Association of Automobile Manufacturers(CAAM) shows that through 2010.China’s automobile sales surpassed 18 million, breaking the world record of annual auto sales previously held by the United States.Now that China has become a major global auto production player, how is Foton faring? CAAM statistics said production and sales volume of展开更多
The main objective of this study is the search for methods of verification of bus rollover finite element simulation which can replace a full-scale verification rollover test using single bus section. An overview of t...The main objective of this study is the search for methods of verification of bus rollover finite element simulation which can replace a full-scale verification rollover test using single bus section. An overview of the main verification methods of the computer simulation results of bus rollover is provided in the article. A bus section rollover test is conducted. A comparison between calculation and experiment results is performed. Features of bus section motion, which affect the construction deformation value, are analyzed on the basis of received good convergence between calculation and test results. The mathematical model of planar motion of the bus section until impact with ditch surface is given. This model can be used to verify values of the center of gravity velocities and accelerations of the bus section, obtained as a result of an FE (finite element) simulation.展开更多
To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sifica...To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sification indexes were extracted using driving data from commercial vehicles and four primary and ten secondary safety evaluation indicators.Based on the stability of commercial vehicles transporting goods,the acceleration index is divided into three levels according to the statistical third quartile,and the evaluation expression of the safety index evaluation is established.Drivers were divided into conservative,moderate,and radical using K-means++.The weights corresponding to each index were calculated using a combination of the analytic hierarchy process(AHP)and criteria importance through intercriteria correlation(CRITIC),and the driving behavior scores of various drivers were calculated according to the safety index score standard.The established AHP-CRITIC safety evaluation model was verified using the actual driving behavior data of commercial vehicle drivers.The calculation results show that the proposed evaluation model can clearly distinguish between the types of drivers with different driving styles,verifying its rationality and validity.The evaluation results can provide a reference for transportation management departments and enterprises.展开更多
Rapid development of Chinese commercial launch vehicles brings new challenges under the traditional systems engineering(TSE)working method.A new model-based systems engineering(MBSE)working method was proposed for Sma...Rapid development of Chinese commercial launch vehicles brings new challenges under the traditional systems engineering(TSE)working method.A new model-based systems engineering(MBSE)working method was proposed for Smart Dragon 1(SD-1),which is a low-cost commercial launch vehicle developed by the China Academy of Launch Vehicle Technology(CALT).Based on the characteristics of a commercial launch vehicle,the system model based on information cards was established.Through a problem-oriented working method,risk identification and management,the process of Card-MBSE was utilized and verified by the success of the maiden flight of SD-1.This paper introduces a new method and reference for the development of low-cost and high-reliability launch vehicles.展开更多
Purpose–Advanced driving assistance system(ADAS)has been applied in commercial vehicles.This paper aims to evaluate the influence factors of commercial vehicle drivers’acceptance on ADAS and explore the characteristi...Purpose–Advanced driving assistance system(ADAS)has been applied in commercial vehicles.This paper aims to evaluate the influence factors of commercial vehicle drivers’acceptance on ADAS and explore the characteristics of each key factors.Two most widely used functions,forward collision warning(FCW)and lane departure warning(LDW),were considered in this paper.Design/methodology/approach–A random forests algorithm was applied to evaluate the influence factors of commercial drivers’acceptance.ADAS data of 24 commercial vehicles were recorded from 1 November to 21 December 2018,in Jiangsu province.Respond or not was set as dependent variables,while six influence factors were considered.Findings–The acceptance rate for FCW and LDW systems was 69.52%and 38.76%,respectively.The accuracy of random forests model for FCW and LDW systems is 0.816 and 0.820,respectively.For FCW system,vehicle speed,duration time and warning hour are three key factors.Drivers prefer to respond in a short duration during daytime and low vehicle speed.While for LDW system,duration time,vehicle speed and driver age are three key factors.Older drivers have higher respond probability under higher vehicle speed,and the respond time is longer than FCW system.Originality/value–Few research studies have focused on the attitudes of commercial vehicle drivers,though commercial vehicle accidents were proved to be more severe than passenger vehicles.The results of this study can help researchers to better understand the behavior of commercial vehicle drivers and make corresponding recommendations for ADAS of commercial vehicles.展开更多
The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for frict...The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for friction and wear is performed on an inertia brake dynamometer (IBD) at different temperatures (200 ℃,250 ℃,and 300 ℃) using 6000 brake actuations in a laboratory.The total wear loss of the brake liner at three different temperatures for 6000 brake actuations in IBD is found to be 1.12 mm.The actual field test is conducted on four different HCVs,namely,a city bus (CB),a high speed bus (HSB),a highway truck (HWT),and a tipper lorry (TL).These HCVs run at different terrain/traffic conditions and load conditions.When comparing the predicted life of the brake liner through the IBD test with the actual life of the brake liner in different HCVs,a vast difference is observed.Due to the large variation of liner life observed between the actual and predicted tests,an extensive field test is conducted.In the field test,the liner with identical formulation is fitted in the four types of HCVs.The predicted life of the liner using IBD is then correlated with the field test observation and a correlation factor is determined.Based on this correlation factor,the predicted life of the liner and the achieved life on the HCV are found to be fairly close.This study will be useful to design the friction material formulation and to predict the actual life of the brake liner for various HCVs.展开更多
For export salesmen of commercial vehicle manufacturers,the second half of 2008 was certainly not the best time. Mr Wang is working at a bus company which exports buses to Russia.From the second half of 2008,he found ...For export salesmen of commercial vehicle manufacturers,the second half of 2008 was certainly not the best time. Mr Wang is working at a bus company which exports buses to Russia.From the second half of 2008,he found that partial clients began cancelling their orders and there were increasing such cases.展开更多
Heavy truck The market trend has recovered since May 2006 and it reported a year on year growth of 30.55 percent by the end of Dec. The result was partly due to the heavy fall in the second half of 2005.
基金Supported by National Natural Science Foundation of China(Grant Nos.51605199,U20A20333,52225212)Six Talent Peak Funding Projects in Jiangsu Province of China(Grant No.2019-GDZB-084)Key Science and Technology Support Program in Taizhou City of China(Grant No.TG202307).
文摘Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving.
基金funded by the Innovation-Driven Development Special Fund Project of Guangxi,Grant No.Guike AA22068060the Science and Technology Planning Project of Liuzhou,Grant No.2021AAA0112the Liudong Science and Technology Project,Grant No.20210117.
文摘The extended Kalman filter (EKF) algorithm and acceleration sensor measurements were used to identify vehiclemass and road gradient in the work. Four different states of fixed mass, variable mass, fixed slope and variableslope were set to simulate real-time working conditions, respectively. A comprehensive electric commercial vehicleshifting strategy was formulated according to the identification results. The co-simulation results showed that,compared with the recursive least square (RLS) algorithm, the proposed algorithm could identify the real-timevehicle mass and road gradient quickly and accurately. The comprehensive shifting strategy formulated had thefollowing advantages, e.g., avoiding frequent shifting of vehicles up the hill, making full use ofmotor braking downthe hill, and improving the overall performance of vehicles.
基金This work was supported in part by the Science and Technology Major Project of Guangxi under Grant AA22068001in part by the Key Research and Development Program of Guangxi AB21196029+3 种基金in part by the Project of National Natural Science Foundation of China 51965012in part by the Scientific Research and TechnologyDevelopment in Liuzhou 2022AAA0102,2021AAA0104 and 2021AAA0112in part by Agricultural Science and Technology Innovation and Extension Special Project of Jiangsu Province NJ2021-21,in part by the Guangxi Key Laboratory of Manufacturing System and Advanced Manufacturing Technology,in part by the Guilin University of Electronic Technology 20-065-40-004Zin part by the Innovation Project of GUET Graduate Education 2022YCXS017.
文摘The reduction of fuel consumption in engines is always considered of vital importance.Along these lines,in this work,this goal was attained by optimizing the heavy-duty commercial vehicle engine control strategy.More specifically,at first,a general first principles model for heavy-duty commercial vehicles and a transient fuel consumptionmodel for heavy-duty commercial vehicles were developed and the parameters were adjusted to fit the empirical data.The accuracy of the proposed modelwas demonstrated fromthe stage and the final results.Next,the control optimization problem resulting in low fuel consumption in heavy commercial vehicles was described,with minimal fuel usage as the optimization goal and throttle opening as the control variable.Then,a time-continuous engine management approach was assessed.Next,the factors that influence low fuel consumption in heavy-duty commercial vehicles were systematically examined.To reduce the computing complexity,the control strategies related to the time constraints of the engine were parametrized using three different methods.The most effective solution was obtained by applying a global optimization strategy because the constrained optimization problem was nonlinear.Finally,the effectiveness of the low-fuel consumption engine control strategy was demonstrated by comparing the simulated and field test results.
文摘今年IAA的口号“Driven by Ideas'(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。今年IAA的口号“Driven by Ideas”(创意驱动)在这场全球最重要的交通、物流和移动性行业贸易展上真正得到了贯彻落实。在汉诺威,未来正在变成看得见的现实。整个商用车行业向IAA观众展示了创新、创造力和先锋精神。这些品质表现在332款产品的全球首发和1 00多款产品的欧洲首发。此次IAA更是决策者的贸易展,并且国际化程度前所未有。
文摘Fire incidents in commercial vehicles pose significant risks to passengers, drivers, and cargo. Traditional fire extinguishing systems, while effective, may have limitations in terms of response time, coverage, and human intervention [1]. This study investigates the efficacy of a novel fire suppression technology—the Exploding Fire Extinguishing Ball (EFEB) —as an alternative and complementary fire safety solution for commercial vehicles. The research employs a multidisciplinary approach, encompassing engineering, materials science, fire safety, and human factors analysis. A systematic literature review establishes a comprehensive understanding of existing fire suppression technologies, including EFEBs. Subsequently, this study analyzes the unique features of EFEBs, such as automatic activation, as well as manual activation upon exposure to fire, and their potential to provide rapid, localized, and autonomous fire suppression. The study presents original experimental investigations to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. Experiments include controlled fires in confined spaces and dynamic simulations to emulate real-world fire incidents. Data on activation times, extinguishing capability, and coverage area are collected and analyzed to compare the efficacy of EFEBs with traditional fire extinguishing methods. Furthermore, this research shows the practical aspects of implementing EFEBs in commercial vehicles. A feasibility study examines the integration challenges, cost-benefit analysis, and potential regulatory implications. The study also addresses the impact of EFEBs on vehicle weight, stability, and overall safety. Human factors and user acceptance are crucial elements in adopting new safety technologies. Therefore, this research utilizes an experimental design to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. This dissertation presents original controlled experiments to emulate real-world fire incidents, including controlled fires in confined spaces and dynamic simulations. The experimental approach ensures rigorous evaluation and objective insights into EFEBs’ potential as an autonomous fire suppression system for commercial vehicles. This includes the perspectives of drivers, passengers, fleet operators, insurance agencies, and regulatory bodies. Factors influencing trust, perceived safety, and willingness to adopt EFEBs are analyzed to provide insights into the successful integration of this technology. The findings of this research will contribute to the knowledge of fire safety technology and expand the understanding of the applicability of EFEBs in commercial vehicles.
文摘New and increasingly sharp laws for the reduction of emissions from commercial vehicles entered into force in the European Union since 1993 with the aim of substan-tially reducing pollutants and emissions from trucks and buses. Thereby the maximum levels for the emission of particulate matter (basically soot particles) as well as oxides of nitrogen (NOx) have been subsequently lowered. To comply with these demands, commercial vehicle producers had to introduce new emission reducing technologies of which exhaust-gas recirculation (EGR),
文摘Improved manufacturing technology is often needed when working with high strength steel. In this re- spect manufacturing technology has to adapt to the altered (and typically reduced) formability and weldability of modern high strength steel. However, this is a rather passive approach from a manufacturing point of view. An indeed much more powerful approach is to generate synergies between innovative manufacturing technology, design and material enabling additional weight savings and efficiency gains. Laser-based material processing, in particular laser welding, offers a wide range of opportunities in this sense. Furthermore, hot stamping and roll forming open up new possibilities for advanced manufacturing of commercial vehicle components. Applications and examples of these technologies will be given in terms of producing innovative semi-products as well as final components.
文摘Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China's energy supply and environment. Thus sustainable development of the Chinese automotive industry must pay significant attention to fuel-saving and emission-reduction of vehicles. Although commercial vehicles make up only about 20% of the entire automobile fleet, their contribution to energy-consumption and emission of pollutants is significant. Thus, priority should be given to fuel-saving and emission-reduction of commercial vehicles. As a result of concerted efforts by Chinese government, industry and enterprises, great progress has been made in technologies concerning new-energy, intelligent and lightweight auto- mobiles. However, compared with developed countries, the level of lightweighting of commercial vehicles produced in China remains comparably low. This means that great potential for development of lightweight commercial vehicles in China exists and it will be an efficient path towards fuel-saving and emission-reduction.
文摘1. An overall judgment on the situation 2006 saw the rapid growth of passenger vehicles, with the production capacity putting into use rose from less than 70 percent to around 80 percent. That with light commercial vehicles was similar too. The situation in 2005 and 2006 showed that there are no evidential overdone production capacity.
文摘When heavy-duty commercial vehicles(HDCVs)must engage in emergency braking,uncertain conditions such as the brake pressure and road profile variations will inevitably affect braking control.To minimize these uncertainties,we propose a combined longitudinal and lateral controller method based on stochastic model predictive control(SMPC)that is achieved via Chebyshev–Cantelli inequality.In our method,SMPC calculates braking control inputs based on a finite time prediction that is achieved by solving stochastic programming elements,including chance constraints.To accomplish this,SMPC explicitly describes the probabilistic uncertainties to be used when designing a robust control strategy.The main contribution of this paper is the proposal of a braking control formulation that is robust against probabilistic friction circle uncertainty effects.More specifically,the use of Chebyshev–Cantelli inequality suppresses road profile influences,which have characteristics that are different from the Gaussian distribution,thereby improving both braking robustness and control performance against statistical disturbances.Additionally,since the Kalman filtering(KF)algorithm is used to obtain the expectation and covariance used for calculating deterministic transformed chance constraints,the SMPC is reformulated as a KF embedded deterministic MPC.Herein,the effectiveness of our proposed method is verified via a MATLAB/Simulink and TruckSim co-simulation.
文摘The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by around 10.15% annually and the sales of medium and heavy trucks by around 18.87% (sales increased from 0.2 million in 2000 to 1.3 million in 2010) according to the National Bureau of Statistics of People's Republic of China. Today commercial vehicles consume almost the same amount of fuel as pas- senger cars in China although the number of commercial vehicles is only about one fourth of passenger cars. It is estimated that around 50% of imported fuel to China each year will be consumed by vehicle transportation. This si- tuation will worsen fuel shortage problems in the long run and at the same time it is partially responsible for the ever- worsening air pollution in China. Due to the widespread overloading in China, lightweight development in commer- cial vehicles has fallen far behind that of passenger cars with the consequences that Chinese commercial vehicles consume in average about 20% more fuel, especially the heavy trucks, compared to European models. Under these circumstances it is essential to reduce the vehicle fuel consumption and in- crease the transport efficiency. The key solution thereby is to implement lightweight design in commercial vehicles as it has been successfully practiced over the last decade in the passenger cars. This paper summarizes highlights given in presentations during the "International seminar on the ap- plication of high strength steels in light weight commercial vehicles" with the focus on the development and application of Nb alloyed high performance steels made for lightweight commercial vehicles.
文摘Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.
文摘Latest data from the China Association of Automobile Manufacturers(CAAM) shows that through 2010.China’s automobile sales surpassed 18 million, breaking the world record of annual auto sales previously held by the United States.Now that China has become a major global auto production player, how is Foton faring? CAAM statistics said production and sales volume of
文摘The main objective of this study is the search for methods of verification of bus rollover finite element simulation which can replace a full-scale verification rollover test using single bus section. An overview of the main verification methods of the computer simulation results of bus rollover is provided in the article. A bus section rollover test is conducted. A comparison between calculation and experiment results is performed. Features of bus section motion, which affect the construction deformation value, are analyzed on the basis of received good convergence between calculation and test results. The mathematical model of planar motion of the bus section until impact with ditch surface is given. This model can be used to verify values of the center of gravity velocities and accelerations of the bus section, obtained as a result of an FE (finite element) simulation.
基金the Natural Science Foundation of Guangxi(No.2020GXNSFDA238011)the Open Fund Project of Guangxi Key Laboratory of Automation Detection Technology and Instrument(No.YQ21203)the Independent Research Project of Guangxi Key Laboratory of Auto Parts and Vehicle Technology(No.2020GKLACVTZZ02)。
文摘To prevent and reduce road traffic accidents and improve driver safety awareness and bad driving be-haviors,we propose a safety evaluation method for commercial vehicle driving behavior.Three driving style clas-sification indexes were extracted using driving data from commercial vehicles and four primary and ten secondary safety evaluation indicators.Based on the stability of commercial vehicles transporting goods,the acceleration index is divided into three levels according to the statistical third quartile,and the evaluation expression of the safety index evaluation is established.Drivers were divided into conservative,moderate,and radical using K-means++.The weights corresponding to each index were calculated using a combination of the analytic hierarchy process(AHP)and criteria importance through intercriteria correlation(CRITIC),and the driving behavior scores of various drivers were calculated according to the safety index score standard.The established AHP-CRITIC safety evaluation model was verified using the actual driving behavior data of commercial vehicle drivers.The calculation results show that the proposed evaluation model can clearly distinguish between the types of drivers with different driving styles,verifying its rationality and validity.The evaluation results can provide a reference for transportation management departments and enterprises.
文摘Rapid development of Chinese commercial launch vehicles brings new challenges under the traditional systems engineering(TSE)working method.A new model-based systems engineering(MBSE)working method was proposed for Smart Dragon 1(SD-1),which is a low-cost commercial launch vehicle developed by the China Academy of Launch Vehicle Technology(CALT).Based on the characteristics of a commercial launch vehicle,the system model based on information cards was established.Through a problem-oriented working method,risk identification and management,the process of Card-MBSE was utilized and verified by the success of the maiden flight of SD-1.This paper introduces a new method and reference for the development of low-cost and high-reliability launch vehicles.
基金sponsored by the National Natural Science Foundation of China(number 52072070)the Foundation for Jiangsu Key Laboratory of Traffic and Transportation Security(TTS2020-04)the Fundamental Research Funds for the Central Universities(number 2242021R10112).
文摘Purpose–Advanced driving assistance system(ADAS)has been applied in commercial vehicles.This paper aims to evaluate the influence factors of commercial vehicle drivers’acceptance on ADAS and explore the characteristics of each key factors.Two most widely used functions,forward collision warning(FCW)and lane departure warning(LDW),were considered in this paper.Design/methodology/approach–A random forests algorithm was applied to evaluate the influence factors of commercial drivers’acceptance.ADAS data of 24 commercial vehicles were recorded from 1 November to 21 December 2018,in Jiangsu province.Respond or not was set as dependent variables,while six influence factors were considered.Findings–The acceptance rate for FCW and LDW systems was 69.52%and 38.76%,respectively.The accuracy of random forests model for FCW and LDW systems is 0.816 and 0.820,respectively.For FCW system,vehicle speed,duration time and warning hour are three key factors.Drivers prefer to respond in a short duration during daytime and low vehicle speed.While for LDW system,duration time,vehicle speed and driver age are three key factors.Older drivers have higher respond probability under higher vehicle speed,and the respond time is longer than FCW system.Originality/value–Few research studies have focused on the attitudes of commercial vehicle drivers,though commercial vehicle accidents were proved to be more severe than passenger vehicles.The results of this study can help researchers to better understand the behavior of commercial vehicle drivers and make corresponding recommendations for ADAS of commercial vehicles.
文摘The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for friction and wear is performed on an inertia brake dynamometer (IBD) at different temperatures (200 ℃,250 ℃,and 300 ℃) using 6000 brake actuations in a laboratory.The total wear loss of the brake liner at three different temperatures for 6000 brake actuations in IBD is found to be 1.12 mm.The actual field test is conducted on four different HCVs,namely,a city bus (CB),a high speed bus (HSB),a highway truck (HWT),and a tipper lorry (TL).These HCVs run at different terrain/traffic conditions and load conditions.When comparing the predicted life of the brake liner through the IBD test with the actual life of the brake liner in different HCVs,a vast difference is observed.Due to the large variation of liner life observed between the actual and predicted tests,an extensive field test is conducted.In the field test,the liner with identical formulation is fitted in the four types of HCVs.The predicted life of the liner using IBD is then correlated with the field test observation and a correlation factor is determined.Based on this correlation factor,the predicted life of the liner and the achieved life on the HCV are found to be fairly close.This study will be useful to design the friction material formulation and to predict the actual life of the brake liner for various HCVs.
文摘For export salesmen of commercial vehicle manufacturers,the second half of 2008 was certainly not the best time. Mr Wang is working at a bus company which exports buses to Russia.From the second half of 2008,he found that partial clients began cancelling their orders and there were increasing such cases.
文摘Heavy truck The market trend has recovered since May 2006 and it reported a year on year growth of 30.55 percent by the end of Dec. The result was partly due to the heavy fall in the second half of 2005.