Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a rea...Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time.展开更多
In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven...In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven roads.First,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force testing.Second,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is discussed.Finally,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration isolator.The experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical vibration.In addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers.展开更多
A global-local finite element modeling technique is employed in this paper to predict the separation in steel cord-rubber composite materials of radial truck tires. The local model uses a finite element analysis in co...A global-local finite element modeling technique is employed in this paper to predict the separation in steel cord-rubber composite materials of radial truck tires. The local model uses a finite element analysis in conjunction with a glob-al-local technique in ABAQUS. A 3-dimensional finite element local model calculates the maximum cyclic shear strain of an interface between steel cord and rubber materials at the carcass ply shoulder region. It is found that the maximum cyclic shear strain is reliable as a result of the analysis of carcass ply separation in radial truck tires. Using the analysis of the local model, a study of the cyclic shear strain is performed in the shoulder region and used to deter-mine the carcass ply separation. The effect of the change of carcass ply design on the separation in steel cord-rubber composite materials of radial truck tires is discussed.展开更多
The localization of damage for bridges to ensure their safety is investigated in this paper. Equivalent element concept is introduced into this study at the beginning. Support reaction data of each bearing under truck...The localization of damage for bridges to ensure their safety is investigated in this paper. Equivalent element concept is introduced into this study at the beginning. Support reaction data of each bearing under truck load are found to be able to lend themselves to indicate damage. A novel index termed as symmetrical support reaction difference index （SSRDI） is then developed. The reverse mapping between the local flexurai stiffness change induced by damage and the SSRDI is generated. The proposed method based on SSRDI can be sensitive to tiny damages, and comparatively simple measurements are required during the application procedure. Another significant attraction of this method is that it can work in the presence of random uncertainties and actual support condition, which means it is suitable for real-world bridges. The effectiveness of the proposed method is demonstrated by numerical simulations performed on two kinds of bridges with reasonable damage severities. Its comparative advantage over the previous frequency method is also investigated.展开更多
In our numerical simulation the hybrid mesh and the SST k-ω turbulence model are adopted to investigate the variations of the aerodynamic loads and the flow field of heavy-duty trucks while crossing a viaduct with 1....In our numerical simulation the hybrid mesh and the SST k-ω turbulence model are adopted to investigate the variations of the aerodynamic loads and the flow field of heavy-duty trucks while crossing a viaduct with 1.1 m high fences in a crosswind at a velocity of 20 m/s. The results show that, with the protection of a fence, the side force is weakened, and the rolling and yaw moments are strengthened while the truck is crossing the viaduct, which relatively reduces the roll-over safety and the driving stability of the truck. Meanwhile, the direction of the side force changes when the truck enters the viaduct, which makes the roll-over safety and the driving stability the lowest during the process.展开更多
During the scenarios of cooperative tasks performed by a single truck and multiple drones,the route plan is prone to failure due to the unpredictable scenario change.In this situation,it is significant to replan the r...During the scenarios of cooperative tasks performed by a single truck and multiple drones,the route plan is prone to failure due to the unpredictable scenario change.In this situation,it is significant to replan the rendezvous route of the truck and drones as soon as possible,to ensure that all drones in flight can return to the truck before running out of energy.This paper addresses the problem of rendezvous route planning of truck and multi-drone.Due to the available time window constraints of drones,which limit not only the rendezvous time of the truck and drones but also the available period of each drone,there are obvious local optimum phenomena in the investigated problem,so it is difficult to find a feasible solution.A two-echelon heuristic algorithm is proposed.In the algorithm,the strategy jumping out of the local optimum and the heuristic generating the initial solution are introduced,to improve the probability and speed of obtaining a feasible solution for the rendezvous route.Simulation results show that the feasible solution of the truck-drones rendezvous route can be obtained with 88%probability in an average of 77 iterations for the scenario involving up to 25 drones.The influence of algorithm options on planning results is also analyzed.展开更多
Medium-duty/heavy-duty trucks(MD/HDTs)are yet to be included in India’s electric mobility plans.With the improvement of electric vehicle(EV)technologies,there is a growing interest in battery-electric trucks(BETs)fro...Medium-duty/heavy-duty trucks(MD/HDTs)are yet to be included in India’s electric mobility plans.With the improvement of electric vehicle(EV)technologies,there is a growing interest in battery-electric trucks(BETs)from original equipment manufacturers(OEMs).The time is opportune to consider electrification as a future direction for road freight in India.Accordingly,this article presents the results of an energy consumption simulation study of a BET under Indian conditions.This study specifically considered an MDBET over a domestic drive cycle.These energy consumption figures can facilitate future studies that analyze the technical and practical feasibility of BETs in the country.In addition,the article provides the requisite groundwork for BET modeling for a simulation study by reviewing available EV powertrain systems and components.Appropriate powertrain considerations are thereby obtained for a typical medium-duty/heavy-duty battery-electric truck(MD/HDBET)in the Indian context.展开更多
基金Supported by International Technology Cooperation Program of Science and Technology Commission of Shanghai Municipality of China(Grant No.21160710600)National Nature Science Foundation of China(Grant No.52372393)Shanghai Pujiang Program of China(Grant No.21PJD075).
文摘Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time.
基金supported by the National Natural Science Foundation of China(No.12172226)。
文摘In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven roads.First,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force testing.Second,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is discussed.Finally,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration isolator.The experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical vibration.In addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers.
文摘A global-local finite element modeling technique is employed in this paper to predict the separation in steel cord-rubber composite materials of radial truck tires. The local model uses a finite element analysis in conjunction with a glob-al-local technique in ABAQUS. A 3-dimensional finite element local model calculates the maximum cyclic shear strain of an interface between steel cord and rubber materials at the carcass ply shoulder region. It is found that the maximum cyclic shear strain is reliable as a result of the analysis of carcass ply separation in radial truck tires. Using the analysis of the local model, a study of the cyclic shear strain is performed in the shoulder region and used to deter-mine the carcass ply separation. The effect of the change of carcass ply design on the separation in steel cord-rubber composite materials of radial truck tires is discussed.
基金National Key Basic Research and Development Program of China (973 program) (No. 2002CB412709)
文摘The localization of damage for bridges to ensure their safety is investigated in this paper. Equivalent element concept is introduced into this study at the beginning. Support reaction data of each bearing under truck load are found to be able to lend themselves to indicate damage. A novel index termed as symmetrical support reaction difference index （SSRDI） is then developed. The reverse mapping between the local flexurai stiffness change induced by damage and the SSRDI is generated. The proposed method based on SSRDI can be sensitive to tiny damages, and comparatively simple measurements are required during the application procedure. Another significant attraction of this method is that it can work in the presence of random uncertainties and actual support condition, which means it is suitable for real-world bridges. The effectiveness of the proposed method is demonstrated by numerical simulations performed on two kinds of bridges with reasonable damage severities. Its comparative advantage over the previous frequency method is also investigated.
基金supported by the National Natural Science Foundation of China(Grant No.50805062)the Development Programs in Science and Technology of Jilin Province(Grant No20096005)
文摘In our numerical simulation the hybrid mesh and the SST k-ω turbulence model are adopted to investigate the variations of the aerodynamic loads and the flow field of heavy-duty trucks while crossing a viaduct with 1.1 m high fences in a crosswind at a velocity of 20 m/s. The results show that, with the protection of a fence, the side force is weakened, and the rolling and yaw moments are strengthened while the truck is crossing the viaduct, which relatively reduces the roll-over safety and the driving stability of the truck. Meanwhile, the direction of the side force changes when the truck enters the viaduct, which makes the roll-over safety and the driving stability the lowest during the process.
基金supported by Guangdong Basic and Applied Basic Research Foundation(Grant No.2022A1515011313)in part by Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2019ZT08Z780)in part by Dongguan Introduction Program of Leading Innovative and Entrepreneurial Talents。
文摘During the scenarios of cooperative tasks performed by a single truck and multiple drones,the route plan is prone to failure due to the unpredictable scenario change.In this situation,it is significant to replan the rendezvous route of the truck and drones as soon as possible,to ensure that all drones in flight can return to the truck before running out of energy.This paper addresses the problem of rendezvous route planning of truck and multi-drone.Due to the available time window constraints of drones,which limit not only the rendezvous time of the truck and drones but also the available period of each drone,there are obvious local optimum phenomena in the investigated problem,so it is difficult to find a feasible solution.A two-echelon heuristic algorithm is proposed.In the algorithm,the strategy jumping out of the local optimum and the heuristic generating the initial solution are introduced,to improve the probability and speed of obtaining a feasible solution for the rendezvous route.Simulation results show that the feasible solution of the truck-drones rendezvous route can be obtained with 88%probability in an average of 77 iterations for the scenario involving up to 25 drones.The influence of algorithm options on planning results is also analyzed.
文摘Medium-duty/heavy-duty trucks(MD/HDTs)are yet to be included in India’s electric mobility plans.With the improvement of electric vehicle(EV)technologies,there is a growing interest in battery-electric trucks(BETs)from original equipment manufacturers(OEMs).The time is opportune to consider electrification as a future direction for road freight in India.Accordingly,this article presents the results of an energy consumption simulation study of a BET under Indian conditions.This study specifically considered an MDBET over a domestic drive cycle.These energy consumption figures can facilitate future studies that analyze the technical and practical feasibility of BETs in the country.In addition,the article provides the requisite groundwork for BET modeling for a simulation study by reviewing available EV powertrain systems and components.Appropriate powertrain considerations are thereby obtained for a typical medium-duty/heavy-duty battery-electric truck(MD/HDBET)in the Indian context.
