基于主动制动的半挂汽车列车横摆稳定性控制

为研究半挂汽车列车在高速大转向等极限操作工况下的横摆稳定性控制问题,建立了14自由度的半挂汽车列车非线性仿真模型;提出了牵引车与半挂车独立直接横摆力矩控制的横摆稳定性控制方案,通过牵引车和半挂车车轮的合理选择和主动制动实现横摆控制;以跟踪参考模型的稳态横摆响应为目标,设计了PI横摆稳定性控制器,对牵引车和半挂车分别设计了目标制动车轮的选择决策规则。单移线操作仿真结果表明,基于主动制动的横摆力矩控制可有效改善极限工况下半挂汽车列车的横摆稳定性,牵引车与半挂车进行独立横摆控制可以减小制动车轮选择决策的复杂性,而获得较好的控制效果。     

Stability Bounds of a Tractor-Semitrailer

The dynamic stability of a tractor-semitrailer is presented here on a qualitative basis. In a four-dimensional space, equilibrium states of the system are discovered which lead to suitable initial conditions for numerical integration of the system equations. The intergal solutions define the stable and the unstable regions in the state-space, and thereby reveal the system behavior. A simple example concerning the effect of a front tire blowout illustrates how the theory can expose the vehicle motion under external perturbations.     

牵引车-半挂车列车动力学仿真研究

在合理的理论假设基础上建立了较为精细的牵引车-半挂车的整车动力学仿真模型。应用此模型,针对6×4牵引车拖挂2轴半挂车列车的折叠、甩尾、倾翻及转向瞬态响应进行了仿真,并对各工况的特点进行了分析。仿真结果表明该模型能够很好地模拟车辆在各种危险工况下的运动状态,从而为进一步研究牵引车-半挂车列车的性能特点提供了很好的工具。     

牵引车-半挂车列车转向稳定性分析

研究了3种用于判别牵引车-半挂车列车稳态转向特性的方法:线性系统稳态转向特性的判别方法、基于动力学仿真的非线性系统稳态转向特性的判别方法、能量相平面判别方法.运用这3种方法分别对某一牵引车-半挂车列车的稳态转向特性进行了判别.结果表明,3种方法相互补充,可以更全面地判别牵引车-半挂车列车的稳态转向特性.     

半挂汽车列车横向稳定性与失稳机理分析

为半挂汽车列车建立了简化的四自由度单轨模型,并在其上分析了两个重要结构参数,即牵引点和挂车质心位置对半挂汽车列车横向稳定性的影响规律.在此基础上,采用主元特征向量分析方法详细探讨了半挂汽车列车"折叠"和"横向摆振"两种常见的横向失稳现象的发生机理,分析和对比了牵引角和牵引角速度输出反馈对半挂汽车列车"折叠"和"横向摆振"失稳的镇定效果.     

用于车辆稳定性控制的直接横摆力矩及车轮变滑移率联合控制研究

设计基于最优控制理论的横摆力矩控制策略和适用于复杂工况的制动力分配策略;设计基于模糊控制理论的滑移率分配算法并提出使横摆力矩控制和变滑移率控制协同工作的方法;最后通过转向盘的阶跃输入和正弦输入工况验证制动力分配策略的正确性和联合控制的有效性。     

基于横摆力矩的汽车稳定性控制策略

为提高车辆的横向稳定性,获得良好的操纵性能,利用ADAMS/car和MATLAB/simulink建立了以横摆角速度和质心侧偏角为控制变量的多级PID仿真模型,分别采用了单个车轮制动和单侧车轮制动产生附加横摆力矩的方式.通过蛇形试验验证了ESP控制器的有效性和对比了2种制动方式的控制效果.仿真试验表明：采用该ESP控制器可以很好地保持车辆的稳定性,采用单侧车轮制动产生附加横摆力矩的方式具有更快的控制速度和更好的控制效果.     

Stability Criteria for Automobile-Trailer Combinations

ABSTRACT

The characteristic equation for a simple automobile-trailer combination is analyzed, revealing the parameter groups which are important in determining the stability characteristics. Application of Routh's method results in separate criteria for oscillatory and non-oscillatory criteria which can be evaluated algebraically, and which can also be displayed graphically showing a region of stability on a two-dimensional plot. The stability region is bounded by limits of oscillatory and non-oscillatory stability, and the evaluation of a specific case corresponds to the location of a point relative to the boundaries.     

Stability Criteria for Automobile-Trailer Combinations

The characteristic equation for a simple automobile-trailer combination is analyzed, revealing the parameter groups which are important in determining the stability characteristics. Application of Routh's method results in separate criteria for oscillatory and non-oscillatory criteria which can be evaluated algebraically, and which can also be displayed graphically showing a region of stability on a two-dimensional plot. The stability region is bounded by limits of oscillatory and non-oscillatory stability, and the evaluation of a specific case corresponds to the location of a point relative to the boundaries.     

基于横摆角速度的汽车ESP系统的仿真研究

横摆角速度是控制汽车横向稳定性的主要控制变量.基于横摆角速度对汽车ESF,系统进行仿真研究,首先在建立ADAMS/CAR中建立汽车整车模型,然后建立汽车理想二自由度参考模型,设计横摆角速度反馈控制PID控制器.仿真结果表明,基于横摆角速度控制的ESP系统控制的汽车明显改善汽车横向稳定性,提高了汽车行驶安全性能.     

直接横摆力矩控制车辆稳定性研究概述

针对直接横摆力矩如何实现汽车的稳定性,与其他一些汽车稳定性控制系统进行了比较。概述了国内外采用的一些直接横摆力矩控制策略及力矩分配方法,并介绍了直接横摆力矩控制在实车上的应用,最后分析了直接横摆力矩的发展趋势。     

Optimal Control of the Tractor-Semitrailer Truck

This paper is concerned with the braking performance and the handling behavior of the tractor-semitrailer truck under optimal braking. Optimal control theory is used in order to deal with the problem and a combination of the steepest descent method and the Davidon Fletcher Powell method is used to solve it numerically. Results for some chosen braking maneuvers are obtained for a nonlinear truck model which has 14 degrees of freedom. These results show that, for the chosen maneuvers an idealized anti-skid braking is close to being optimal in the sense defined in this paper. Implementation of an idealized anti-skid braking on the tractor-semitrailer truck, however, may be not desirable.     

半挂汽车列车转向分析

研究了半挂汽车列车的最小转弯直径、转弯通道圆和直角通道宽度理论计算方法,介绍了如何分析半挂汽车列车在公路上行驶时的通过性能。     

Optimal Control of the Tractor-Semitrailer Truck

SUMMARY

This paper is concerned with the braking performance and the handling behavior of the tractor-semitrailer truck under optimal braking. Optimal control theory is used in order to deal with the problem and a combination of the steepest descent method and the Davidon Fletcher Powell method is used to solve it numerically. Results for some chosen braking maneuvers are obtained for a nonlinear truck model which has 14 degrees of freedom. These results show that, for the chosen maneuvers an idealized anti-skid braking is close to being optimal in the sense defined in this paper. Implementation of an idealized anti-skid braking on the tractor-semitrailer truck, however, may be not desirable.     

车辆横摆角速度估算方法的研究

总结和归纳了车辆横摆角速度估算的方法,给出了基于运动学模型和动力学模型的横摆角速度估算的基本算法．许分析了各种方法的优缺点,指出了横摆角速度估算研究的重要实际意义。     

Random Response of Tractor-Semitrailer System

This work describes an analytical study of the dynamic behaviour of a tractor-semitrailer vehicle. A digital computer simulation was used to describe the longitudinal, vertical, and pitching motions of the vehicle travelling over a stationary random road surface. A man-seat model was also incorporated into the simulation. Vehicle response to road irregularities has been studied by assuming two different roads for loaded and unloaded cases.

Numerical results are presented for vehicle, showing system eigenvalues, power spectral densities and root mean square values of the linear and angular accelerations and displacements. Vehicle acceleration response is compared with the ISO riding comfort standard. All results for the loaded and unloaded cases and for smooth and rough roads indicated that an uncomfortable ride would result from vehicle response.     

Random Response of Tractor-Semitrailer System

SUMMARY

This work describes an analytical study of the dynamic behaviour of a tractor-semitrailer vehicle. A digital computer simulation was used to describe the longitudinal, vertical, and pitching motions of the vehicle travelling over a stationary random road surface. A man-seat model was also incorporated into the simulation. Vehicle response to road irregularities has been studied by assuming two different roads for loaded and unloaded cases.

Numerical results are presented for vehicle, showing system eigenvalues, power spectral densities and root mean square values of the linear and angular accelerations and displacements. Vehicle acceleration response is compared with the ISO riding comfort standard. All results for the loaded and unloaded cases and for smooth and rough roads indicated that an uncomfortable ride would result from vehicle response.     

Closed-Loop Directional Stability of Car-Trailer Combinations in Straight-Line Motion

This work focuses on the interaction between a driver and a car-trailer combination. A model characterizing human operator behavior in regulation task is employed to study directional stability of the overall system. The vehicle-trailer model retains nonlinear cornering force and other kinematic nonlinearities. Linear stability of the straight line motion is analyzed by the application of Routh-Hurwitz criteria and stability boundaries in parameter space are constructed by setting appropriate Hurwitz determinant to zero. It is shown that two types of transition in stability are possible in the driver/car-trailer system. They correspond to one pair or two pairs of complex conjugate eigenvalues crossing the imaginary axis simultaneously. The implications in terms of resulting motions for the nonlinear system are also discussed. It is shown that stabilization of the combination can be achieved by adding a passive controller at the articulation point. Articulation damper turns out to be a more useful device for controlling trailer oscillations instability although a combination of damper and torsional spring would be a more ideal solution.     

Closed-Loop Directional Stability of Car-Trailer Combinations in Straight-Line Motion

SUMMARY

This work focuses on the interaction between a driver and a car-trailer combination. A model characterizing human operator behavior in regulation task is employed to study directional stability of the overall system. The vehicle-trailer model retains nonlinear cornering force and other kinematic nonlinearities. Linear stability of the straight line motion is analyzed by the application of Routh-Hurwitz criteria and stability boundaries in parameter space are constructed by setting appropriate Hurwitz determinant to zero. It is shown that two types of transition in stability are possible in the driver/car-trailer system. They correspond to one pair or two pairs of complex conjugate eigenvalues crossing the imaginary axis simultaneously. The implications in terms of resulting motions for the nonlinear system are also discussed. It is shown that stabilization of the combination can be achieved by adding a passive controller at the articulation point. Articulation damper turns out to be a more useful device for controlling trailer oscillations instability although a combination of damper and torsional spring would be a more ideal solution.