【作者】 夏光；

【导师】 陈无畏；

【作者基本信息】 合肥工业大学 ， 车辆工程， 2013， 博士

【摘要】 随着现代汽车制造和汽车技术水平的快速发展,各种电子控制技术在汽车上的应用越来越广泛,半主动悬架系统(Semi-active Suspension system, SASS)和电子稳定程序(Electronic Stability Program, ESP)的应用大大改善了汽车的行驶平顺性、操纵稳定性和安全性。为弥补底盘各可控子系统功能范围有限的缺点,对汽车底盘多个子系统进行集成控制以发掘各子系统的功能潜力成为汽车动力学的研究热点。本文首先对SASS和ESP进行深入研究,在此基础上对两系统的集成控制进行了理论分析和试验研究。首先在轮胎非线性特性分析的基础上,建立能反映汽车纵向、侧向和垂向动力学相互作用关系的整车动力学模型,较好地反映底盘悬架、制动和转向等子系统间相互影响关系和轮胎的非线性特性。深入研究一种新型电磁阀式阻尼连续可调减振器的结构与阻尼产生机理,建立较为准确的连续可调减振器复原行程、压缩行程液压与数学模型,分析减振器主要结构参数对阻尼特性的影响,并在单通道电液伺服悬架动态性能试验台进行台架试验,为电磁阀式减振器的设计和工程化提供理论参考。采用H∞控制算法设计侧重于不同控制目标的半主动悬架控制器,提升整车多工况下的综合性能。考虑路面附着系数对轮胎力的限制,提出一种基于纵向合力和横摆力矩计算与分配的汽车稳定性控制方法。采用离线数值优化法实时确定纵向合力和横摆力矩可行域,并将纵向合力和横摆力矩调整到可行域内。采用三层BP网络构造轮胎力逆模型,将纵向合力和横摆力矩动态分配至车轮,在保证精度的前提下避免了对后轮侧向力的估计,可较好地跟踪横摆角,提高轨迹保持能力,改善低附着路面对汽车稳定性的影响,并进行基于LabVIEW PXI和veDYNA的汽车ESP驾驶员在环试验验证。针对汽车SASS与ESP子系统间的集成控制问题,提出一种功能分配协调控制方法。上层功能分配控制器根据汽车工况及当前工况下的主要控制目标的变化,利用模糊推理方法确定汽车工况与底层子系统功能分配系数间的关系,得到各子控制器的输出权重；对底层ESP和SASS子控制器的初始功能分配系数进行调节,对子系统中某些功能进行加强或削弱,达到提升当前工况下整车性能最优的目标,同时也提高子系统工作效率,降低底层控制器设计难度。基于ARM7开发平台进行SASS控制系统软硬件设计,并进行基于CAN总线进行信号共享、传输和控制指令传送的上层功能分配协调控制器开发。最后装车进行SASS系统道路试验和SASS与ESP两系统集成控制实车试验研究,验证控制效果。更多还原

【Abstract】 With the rapid development of modern automobile manufacturing and technical level, a variety of electronic control technology is widely applied in the automobiles, the applications of the semi-active suspension system (SASS) and the Electronic Stability Program (ESP) has greatly improved the ride comfort, handling stability and security. To make up for the disadvantages, the limited range of functions for the controllable subsystems of chassis, the integrated control on tht multiple subsystems of the chassis in order to explore the potential functions has become a research hotspot of the vehicle dynamics. The dissertation author investigates the depth study of the semi-active suspension system with solenoid valve damper(SASS) and the Electronic Stability Program (ESP) then the the theoretical analysis and experimental research.for the integrated control of the two subsystems are achieved.On the basis of the analysis of the nonlinear characteristics of the tire,the vehicle dynamics model that reflects the interaction between the vehicle longitudinal, lateral and vertical dynamics, has been established. which can better reflect the influenced relationship and non-linear characteristics of the tire.of the chassis, suspension, braking and steering subsystems.The structure and principle of a new type of continuously adjustable damper with solenoid valve is studied.thoroughly, the hydraulic model the mathmatic model of rebounce stroke and compress stroke are established.The main structure parameters to the damping characteristic are analysed, the damper is tested on the lch dynamic servo suspension tester, and the theoretical reference is provided for the design and engineering of the continuously adjustable damper with solenoid valve.The control algorithm of H∞is applied to design the Semi-active suspension controller for enhancing whole vehicle synthesis performance in a multi-conditions.Considering the restriction of the road adhesion coefficient to tire force, the method of vehicle stability control is proposed, which is based on the calculation and allocation to the longitudinal composition of forces and yaw torque. The feasible region of the longitudinal composition of forces and yaw torque is determined in real time by offline numerical optimization metod, and the longitudinal composition of forces and yaw torque is adjusted to the feasible region, the longitudinal composition of forces and yaw torque is dynamically allocated to the wheels adopted the tire force inverse model structure by the three layer BP network, avoiding the lateral forces estimated of the rear wheels under the accuracy ensured, it can track the yaw angle better, improve track holding capacity and the influence of the low adhesion road to the vehicle stability, and a driver-in-the-loop test of Lab VIEW PXI and veDYNA have been carried up to verify the effectiveness of the control strategy.A coordinated control method based on the function allocation is proposed with regard to integration control problems of SASS and ESP subsystem.The upper function allocation controller can get the output weights of each controller, adjust the initial allocation coefficient of the sub ESP and SASS controller, strength or weak some function of subsystem, and the relationship between vehicle conditions and the function allocation coefficient of the bottom subsystems is determined by the method of fuzzy reasoning which is based on vehicle conditions and the changes of main control objectives under the current conditions.It can enhance optimal vehicle performance goals under the current conditions, but also improve the efficiency of the subsystem, reduce the design difficulty.of sub-controllerThe hardware and software system design of the SASS control system is carried out based on ARM7development platform, the SASS and ESP coordinated controller based on the function allocation which the signals shared, transmission and control command sent is based on the CAN bus. Finally, the controllers have been equipped on the vehicle and the experimental study of the SASS and integrated control of two systems are carried up to verify the effectiveness of the control strategy.更多还原