The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calcula...The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calculated using the state-of-the-art space-time separation principle that separates the Emergency Braking(EB)trajectories of two successive units during the whole EB process.In this case,the minimal safety distance is usually numerically calculated without an analytic formulation.Thus,the constrained VCTS control problem is hard to address with space-time separation,which is still a gap in the existing literature.To solve this problem,we propose a Distributed Economic Model Predictive Control(DEMPC)approach with computation efficiency and theoretical guarantee.Specifically,to alleviate the computation burden,we transform implicit safety constraints into explicitly linear ones,such that the optimal control problem in DEMPC is a quadratic programming problem that can be solved efficiently.For theoretical analysis,sufficient conditions are derived to guarantee the recursive feasibility and stability of DEMPC,employing compatibility constraints,tube techniques and terminal ingredient tuning.Moreover,we extend our approach with globally optimal and distributed online EB configuration methods to shorten the minimal distance among VCTS.Finally,experimental results demonstrate the performance and advantages of the proposed approaches.展开更多
A new efficient adapting virtual intermediate instruction set,V-IIS,is designed and implemented towards the optimized dynamic binary translator (DBT) system.With the help of this powerful but previously little-studied...A new efficient adapting virtual intermediate instruction set,V-IIS,is designed and implemented towards the optimized dynamic binary translator (DBT) system.With the help of this powerful but previously little-studied component,DBTs can not only get rid of the dependence of machine(s),but also get better performance.From our systematical study and evaluation,experimental results demonstrate that if V-IIS is well designed,without affecting the other optimizing measures,this could make DBT's performance close to those who do not have intermediate instructions.This study is an important step towards the grand goal of high performance "multi-source" and "multi-target" dynamic binary translation.展开更多
基金supported by the National Natural Science Foundation of China(52372310)the State Key Laboratory of Advanced Rail Autonomous Operation(RAO2023ZZ001)+1 种基金the Fundamental Research Funds for the Central Universities(2022JBQY001)Beijing Laboratory of Urban Rail Transit.
文摘The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calculated using the state-of-the-art space-time separation principle that separates the Emergency Braking(EB)trajectories of two successive units during the whole EB process.In this case,the minimal safety distance is usually numerically calculated without an analytic formulation.Thus,the constrained VCTS control problem is hard to address with space-time separation,which is still a gap in the existing literature.To solve this problem,we propose a Distributed Economic Model Predictive Control(DEMPC)approach with computation efficiency and theoretical guarantee.Specifically,to alleviate the computation burden,we transform implicit safety constraints into explicitly linear ones,such that the optimal control problem in DEMPC is a quadratic programming problem that can be solved efficiently.For theoretical analysis,sufficient conditions are derived to guarantee the recursive feasibility and stability of DEMPC,employing compatibility constraints,tube techniques and terminal ingredient tuning.Moreover,we extend our approach with globally optimal and distributed online EB configuration methods to shorten the minimal distance among VCTS.Finally,experimental results demonstrate the performance and advantages of the proposed approaches.
基金Projects(12R21414600)supported by Shanghai Municipal Science and Technology Commission,China
文摘A new efficient adapting virtual intermediate instruction set,V-IIS,is designed and implemented towards the optimized dynamic binary translator (DBT) system.With the help of this powerful but previously little-studied component,DBTs can not only get rid of the dependence of machine(s),but also get better performance.From our systematical study and evaluation,experimental results demonstrate that if V-IIS is well designed,without affecting the other optimizing measures,this could make DBT's performance close to those who do not have intermediate instructions.This study is an important step towards the grand goal of high performance "multi-source" and "multi-target" dynamic binary translation.