The introduction ofproportional-integral-dorivative （PID） controllers into cooperative collision avoidance systems （CCASs） has been hindered by difficulties in their optimization and by a lack of study of their ef...The introduction ofproportional-integral-dorivative （PID） controllers into cooperative collision avoidance systems （CCASs） has been hindered by difficulties in their optimization and by a lack of study of their effects on vehicle driving stability, comfort, and fuel economy. In this paper, we propose a method to optimize PID controllers using an improved particle swarm optimization （PSO） algorithm, and to bettor manipulate cooperative collision avoidance with other vehicles. First, we use PRESCAN and MATLAB/Simulink to conduct a united simulation, which constructs a CCAS composed of a PID controller, maneuver strategy judging modules, and a path planning module. Then we apply the improved PSO algorithm to optimize the PID controller based on the dynamic vehicle data obtained. Finally, we perform a simulation test of performance before and after the optimization of the PID controller, in which vehicles equipped with a CCAS undertake deceleration driving and steering under the two states of low speed （≤50 km/h） and high speed （≥100 km/h） cruising. The results show that the PID controller optimized using the proposed method can achieve not only the basic functions of a CCAS, but also improvements in vehicle dynamic stability, riding comfort, and fuel economy.展开更多
The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), t...The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), the experimental results show that the device A has a superior lean blowout performance when the combustor reference velocity is within the range from 3.50m/s to 5.59m/s ( while the liner reference velocity is between 3.84 and 6.13m/s), and this superiority will remain stable after the inlet air flow rate reaches a certain value. In order to analyze the phenomena and experimental results, the numerical simulation method is used, and the strain rate and the cold reflux impact are employed to further explain the reason that causes the difference between the two devices' lean blowout characteristics.展开更多
基金Project supported by the National Natural Science Foundation o4 China （No. 61300145）
文摘The introduction ofproportional-integral-dorivative （PID） controllers into cooperative collision avoidance systems （CCASs） has been hindered by difficulties in their optimization and by a lack of study of their effects on vehicle driving stability, comfort, and fuel economy. In this paper, we propose a method to optimize PID controllers using an improved particle swarm optimization （PSO） algorithm, and to bettor manipulate cooperative collision avoidance with other vehicles. First, we use PRESCAN and MATLAB/Simulink to conduct a united simulation, which constructs a CCAS composed of a PID controller, maneuver strategy judging modules, and a path planning module. Then we apply the improved PSO algorithm to optimize the PID controller based on the dynamic vehicle data obtained. Finally, we perform a simulation test of performance before and after the optimization of the PID controller, in which vehicles equipped with a CCAS undertake deceleration driving and steering under the two states of low speed （≤50 km/h） and high speed （≥100 km/h） cruising. The results show that the PID controller optimized using the proposed method can achieve not only the basic functions of a CCAS, but also improvements in vehicle dynamic stability, riding comfort, and fuel economy.
基金supported by the National Natural Science Foundation of China (No. 50876104)the Major State Basic Research Development Scheme of China (No. 2012CB720406)
文摘The lean blowout experiments of the combustion stability device A (multi-vortexes-dome model combustor) have been carried out at atmospheric pressure. Compared with the device B (single-vortex-dome model combustor), the experimental results show that the device A has a superior lean blowout performance when the combustor reference velocity is within the range from 3.50m/s to 5.59m/s ( while the liner reference velocity is between 3.84 and 6.13m/s), and this superiority will remain stable after the inlet air flow rate reaches a certain value. In order to analyze the phenomena and experimental results, the numerical simulation method is used, and the strain rate and the cold reflux impact are employed to further explain the reason that causes the difference between the two devices' lean blowout characteristics.
