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车队密度散布模型及在车队截尾问题上的应用 总被引:3,自引:0,他引:3
道德运用流体动力学模拟理论微观地分析了车队在信号灯交叉口的排队队长的变化特性;以此为基础,研究车队散布中的密度变化规律,提出密度散布模型,并且将该模型用来推导散布车队尾部在下游信号灯被截车辆数的数学表达式,这可用于交叉口信号协调控制。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):247-280
A new methodology to design the vehicle GCC (global chassis control) nonlinear controller is developed in this paper. Firstly, to handle the nonlinear coupling between sprung and unsprung masses, the vehicle is treated as a mechanical system of two-rigid-bodies which has 6 DOF (degree of freedom), including longitudinal, lateral, yaw, vertical, roll and pitch dynamics. The system equation is built in the yaw frame based on Lagrange's method, and it has been proved that the derived system remains the important physical properties of the general mechanical system. Then the GCC design problem is formulated as the trajectory tracking problem for a cascade system, with a Lagrange's system interconnecting with a linear system. The nonlinear robust control design problem of this cascade interconnected system is divided into two H ∞ control problems with respect to the two sub-systems. The parameter uncertainties in the system are tackled by adaptive theory, while the external uncertainties and disturbances are dealt with the H ∞ control theory. And the passivity of the mechanical system is applied to construct the solution of nonlinear H ∞ control problem. Finally, the effectiveness of the proposed controller is validated by simulation results even during the emergency manoeuvre. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):991-1011
A robust nonparametric approach to vehicle stability control by means of a four-wheel steer by wire system is introduced. Both yaw rate and sideslip angle feedbacks are used in order to effectively take into account safety as well as handling performances. Reference courses for yaw rate and sideslip angle are computed on the basis of the vehicle speed and the handwheel angle imposed by the driver. An output multiplicative model set is used to describe the uncertainty arising from a wide range of vehicle operating situations. The effects of saturation of the control variables (i.e. front and rear steering angles) are taken into account by adopting enhanced internal model control methodologies in the design of the feedback controller. Actuator dynamics are considered in the controller design. Improvements on understeer characteristics, stability in demanding conditions such as turning on low friction surfaces, damping properties in impulsive manoeuvres, and improved handling in closed loop (i.e. with driver feedback) manoeuvres are shown through extensive simulation results performed on an accurate 14 degrees of freedom nonlinear model, which proved to give good modelling results as compared with collected experimental data. 相似文献
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J. Song 《International Journal of Automotive Technology》2016,17(2):265-272
We report a model and controller for an active front-wheel steering (AFS) system. Two integrated dynamics control (IDC) systems are designed to investigate the performance of the AFS system when integrated with braking and steering systems. An 8-degrees-of-freedom vehicle model was employed to test the controllers. The controllers were inspected and compared under different driving and road conditions, with and without braking input, and with and without steering input. The results show that the AFS system performs kinematic steering assistance function and kinematic stabilisation function very well. Three controllers allowed the yaw rate to accurately follow a reference yaw rate, improving the lateral stability. The two IDC systems improved the lateral stability and vehicle control and were effective in reducing the sideslip angle. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):657-683
The design of the integrated active front steering and active differential control for handling improvement of road vehicles is undertaken. The controller design algorithm is based on the solution of a set of linear matrix inequalities that guarantee robustness against a number of vehicle parameters such as speed, cornering and braking stiffnesses. Vehicle plane dynamics are first expressed in the generic linear parameter-varying form, where the above-stated parameters are treated as interval uncertainties. Then, static-state feedback controllers ensuring robust performance against changing road conditions are designed. In a first series of simulations, the performance of the integrated controller is evaluated for a fishhook manoeuvre for different values of road adhesion coefficient. Then, the controller is tested for an emergency braking manoeuvre executed on a split-μ road. In all cases, it is shown that static-state feedback controllers designed by the proposed method can achieve remarkable road handling performance compared with uncontrolled vehicles. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1150-1171
In this paper, a multiple surface sliding controller is designed for an anti-lock braking system to maintain the slip ratio at a desired level. Various types of uncertainties coming from unknown road surface conditions, the variations in normal force and the mass of the vehicle are estimated using an uncertainty estimation technique called the inertial delay control and then the estimate is used in the design of the multiple surface sliding controller. The proposed scheme does not require the bounds of uncertainties. The ultimate boundedness of the overall system is proved. The proposed scheme is validated by simulation under various scenarios of road friction, road gradient and vehicle loading followed by experimentation on a laboratory anti-lock braking set-up for different friction conditions. 相似文献
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阐述了大跨度预应力混凝土连续刚构桥高程控制的重要意义,提出了高程控制原则和方法,分析了高程控制的主要影响因素。并以某大跨径预应力钢筋混凝土连续刚构桥的高程控制为依托,应用桥梁结构分析程序BRCAD,建立计算模型,计算各阶段的理论的高程,以最小二乘法为基础进行参数识别的误差分析和状态预测法进行标高控制,比较合拢成桥后实测高程和理论计算高程,分析了产生偏差的原因,其可供同类的桥型的高程控制提供有价值的参考。 相似文献
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K. -H. Moon S. -H. Lee S. Chang J. -K. Mok T. -W. Park 《International Journal of Automotive Technology》2009,10(4):441-449
Many methods we have been developed to control the rear wheels of a vehicle, but most of them are designed for automobiles
with four wheels. The AWS (all wheel steering) control method for articulated vehicles is currently applied only to Phileas
vehicles developed by APTS, but the control algorithm for this system has yet to be reported. In the present paper, a new
algorithm is proposed after the AWS ECU (electronic control unit) of the Phileas vehicle was tested and analyzed in order
to understand the existing steering algorithm. The new algorithm considers the vehicle geometry, stability of handling, and
safety, and can be easily applied to multi-axle vehicles. In order to verify the AWS algorithm, the trajectory and steering
angles of each algorithm were compared using the commercial software ADAMS. Turning radius, swing-out, and swept path width
were also investigated to determine the turning performance of the proposed algorithm. 相似文献
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通过对液力变矩器的特性进行分析,建立了车辆常用的综合式液力变矩器的数学模型,并研究了与发动机共同工作特性,提出了合理匹配系数。 相似文献
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讨论了可编程控制器(PLC)在多台柴油发电机组自动并列控制系统中应用。结合实际应用工程的具体设计分别对其实现的软件及硬件作了详细的说明。 相似文献
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This research applies R-Markov Average Reward Technique based reinforcement learning (RL) algorithm, namely RMART, for vehicular signal control problem leveraging information sharing among signal controllers in connected vehicle environment. We implemented the algorithm in a network of 18 signalized intersections and compare the performance of RMART with fixed, adaptive, and variants of the RL schemes. Results show significant improvement in system performance for RMART algorithm with information sharing over both traditional fixed signal timing plans and real time adaptive control schemes. The comparison with reinforcement learning algorithms including Q learning and SARSA indicate that RMART performs better at higher congestion levels. Further, a multi-reward structure is proposed that dynamically adjusts the reward function with varying congestion states at the intersection. Finally, the results from test networks show significant reduction in emissions (CO, CO2, NOx, VOC, PM10) when RL algorithms are implemented compared to fixed signal timings and adaptive schemes. 相似文献
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