【作者】 初长宝；

【导师】 陈无畏；

【作者基本信息】 合肥工业大学 ， 车辆工程， 2008， 博士

【摘要】 随着汽车底盘一体化集成控制系统的不断发展,对底盘系统的集成控制研究愈加紧迫。基于此,本文对汽车底盘系统中的悬架系统、电动助力转向系统及制动系统进行了分层式协调控制研究。分层式协调控制策略与集中控制、分散控制相比,具有控制器设计复杂程度低、控制系统稳定性高、便于集成控制系统扩展等优点,为汽车底盘一体化集成控制提供了新思路。本文以半车为研究对象,首先对悬架系统、电动助力转向系统及制动系统分别建立数学模型,模型的建立并不考虑子系统间的相互影响,采用不同控制方法对各子系统进行控制器设计,并进行了仿真研究。然后,利用前面设计好的各子系统控制器作为底层控制器,在深入分析悬架系统与制动系统、电动助力转向系统与制动系统以及三系统间的相互影响的基础上,设计了上层协调控制器。上层协调控制器是一个决策控制器,起到了对底层控制器决策、监控的作用。它相当于一个选择开关:当车辆正常行驶时,上层协调控制器起到了监控各底层控制器的作用,各传感器信号通过CAN总线传输到上层协调控制器,对主要指标进行监控;当出现异常情况时(如紧急制动),上层协调控制器对主要指标进行监控,发现异常后对底层控制器发出决策指令。仿真结果表明:采用分层式协调控制策略,在保证子系统性能良好的情况下,汽车综合性能得到提高。本文的试验研究较为深入。首先基于LabVIEW开发平台进行了防抱制动系统硬件在环试验,缩短了ABS电子控制单元的开发周期;然后基于ARM7和protel开发平台进行了ABS、EPS实际控制器的开发;最后,基于分层协调控制策略,设计了上层协调控制器,以协调ABS、EPS之间的矛盾性。试验结果表明:底层ABS、EPS子控制器控制逻辑正确,上层协调器决策控制输出设计合理,在降低较少制动性能基础上,车辆的操纵性能、横向稳定性能得到较大提高,从而获得良好的综合性能。更多还原

【Abstract】 Along with the development of vehicle chassis integrated control, research on it became more urgent. Under this circumstance, research on layered coordinated control among suspension system, electric power steering system and braking system was carried out. Compared with concentrated control and distributed control, advantages of layered coordinated control can be described as follows: complication of controller design is decreased, control stability is improved and it is easier to extend control subsystem. Layered coordinated control supplied a new method for vehicle chassis integrated control.Based on semi-vehicle model, mathematical model was separately established for suspension system, electric power steering system (EPS) and braking system. During the course of model establishment, influences among subsystems were not taken into account. Different control methods were adopted for controllers’ design of subsystems, the simulation research was carried out. Took controllers designed for subsystems as bottom controllers, upper coordinated controller was designed based on deeply analyzing the influences among suspension system, electric power steering system and braking system. Upper coordinated controller was a decision-making controller, the function was to make decisions and monitor bottom controllers. Just like a switch, upper coordinated controller only monitored bottom controllers when vehicle ran normally. Sensor signals were transmitted to upper coordinated controller through CAN bus; when exceptional circumstances happened such as emergency brake, main indexes were monitored and the decisions were made by upper coordinated controller. Simulation results show that vehicle synthesis performance is improved adopting layered coordinated control.Deeply experimentation research was carried out. First, hardware in the loop(HIL) experiment of anti-lock braking system(ABS) was carried out, the developing periods of ABS electronic control unit (ECU)was obviously decreased. Second, controllers’ development of ABS and EPS were carried out based on ARM7 and protel software platform. At last, based on layered coordinated control strategy, upper coordinated controller was designed in order to coordinate the contradictions between ABS and EPS. The experimentation results show that decision-making of upper coordinated controller is logical and control logic of bottom controllers is correct. Vehicle maneuver performance and lateral stabilization are obviously improved based on decreasing brake performance. A better vehicle synthesis performance can be achieved by using layered coordinated control.更多还原