无人驾驶智能车制动控制系统研究
分类号:U27;U46 10710-2010122010 硕硕 士士 学学 位位 论论 文文 无人驾驶智能车制动控制系统研究 肖焱曦 导师姓名职称 余强 教授 申请学位级别 工学硕士 学科专业名称 车辆工程 论文提交日期 2013年 5月10日 论文答辩日期 2013年 6 月 13日 学位授予单位 长安大学 Research on the Braking System of Unmanned Intelligent Vehicle A Dissertation Submitted for the Degree of Master Candidate：Xiao Yanxi Supervisor：Prof. Yu Qiang Changan University, Xian, China i 摘摘 要要 随着汽车技术的快速发展，车辆控制技术得到长足的进步。运用计算机技术实现汽车智能化成为当今汽车技术发展的重要方向。近年来，国内外的研究机构和企业对无人驾驶智能汽车开展了一系列研究。无人驾驶智能车通过传感器感知周围环境，经过主控计算机分析、计算得出路径规划，最后通过控制转向及速度最终实现自主驾驶。智能车的控制系统分为上层规划系统与底层控制系统，上层规划系统主要完成收集信息、分析规划、发送指令等任务，而底层控制系统则是直接实现对车辆的控制。制动系统作为底层控制系统的一部分，与无人驾驶汽车的安全运行息息相关，因此，设计高稳定性、高可靠性的制动控制系统并对其特性展开研究成为智能汽车研发的重要环节。 本文是对无人驾驶智能车底层控制系统中制动系统的研究，首先对于具体方案的选择上，选择通过机械机构控制踏板机构实现对车辆制动的控制，依据该思路，设计了一套以无刷直流电机为动力的执行机构。接着，围绕着制动系统与无刷直流电机提出主缸压力与电机电流双闭环控制理论，依据电机工作原理、控制原理与闭环系统设计，选择了性能优良的电机控制器件与系统反馈器件。然后，设计了以数字处理器为核心、电机为动力输出的制动控制系统，针对控制系统设计硬件和软件，实现通过对电机的控制达到对制动主缸压力控制的目的。最后，建立执行机构数学模型，分析制动系统数学模型非线性性，简化制动系统数学模型，为仿真分析做出准备。利用 MATLAB/Simulink 对其进行阶跃响应仿真以模拟紧急制动工况，进行斜坡响应仿真以模拟轻微制动工况，仿真结果一致表明该制动控制系统能够满足无人驾驶智能汽车的制动要求。 本文对无人驾驶汽车的制动系统的成功开发提出一些阶段性的经验总结，该研究为汽车主动安全、汽车智能制动控制和汽车辅助驾驶等技术领域提供了一些有益尝试，有助于减轻和缓解驾驶员身心疲劳。 关键词：无人驾驶智能车；制动系统；直流无刷电机；数字信号处理器 ii Abstract With the rapid development of automobile technology, vehicle control technology has made great progress. The use of computer technology to achieve intelligent vehicle become an important direction for the development of automotive technology. In recent years, domestic and foreign research institutions and enterprises to carry out a series of unmanned intelligent vehicle research. Unmanned intelligent vehicle through the sensors aware of their surroundings, through the host computer analysis and calculate to get the path planning. Finally, by controlling the steering and speed to achieve autonomous driving. Intelligent vehicle control system is divided into the upper planning system and the underlying control systems. The Upper planning system was completed to gather information, analysis and planning, to send commands and other tasks.While, the underlying control system is achieve the direct control of the vehicle. Braking system as the underlying part of the control system is closely related to the safe operation of unmanned vehicles.Therefore, the design of high stability, and high reliability characteristics of the brake control system, and research on its characteristics have become an important part of intelligent vehicle development. This paper intends to modeling and analysis on unmanned intelligent car brake system, on the base of the vehicle modification on brake system design, build and refit from the prototype vehicle, developed the hardware and software two key module, proposed a mathematical model of the control system, using the method of add mechanical components control the brake pedal, selected the DSP driver module by changing the PWM pulse width control DC motor input voltage for different torque method, designed a set of DC servo motor as the power source for the actuator to control the brake pedal. Around the motor control system, designed the motor drive module, hydraulic close-loop feedback module. For motor drive module design of hardware and software to achieve the speed of the servo motor and servo brake line pressure. The actuator established mathematical model to analyze the nonlinear mathematical model of brake systems and simplified mathematical model of brake systems, to make preparations for the simulation analysis. Using MATLAB/Simulink simulation to simulate the step response of emergency braking condition, slight slope to simulate the response of the braking conditions, consistent with the simulation results show that the brake control system can meet the braking requirements of unmanned intelligent vehicle. This article aims at raise some initial summary of the experiences on unmanned vehicle braking system successfully developed. The research for the automotive active safety, vehicle intelligent brake control and the auxiliary driving technology provides some beneficial attempt to help reduce and relieve physical and mental fatigue of drivers. Key Words: Unmanned intelligent vehicle; Braking system; Brushless DC motor; Digital Signal Processing iii 目目 录录 第一章 绪论 . 1 1.1 智能车的研究背景及意义 . 1 1.2 智能车国内外研究现状 . 2 1.2.1 国外无人驾驶智能车研究现状 . 2 1.2.2 国内无人驾驶智能车的研究现状 . 3 1.3 智能车的控制系统 . 5 1.3.1 智能车研究的关键问题 . 5 1.3.2 智能车的控制系统 . 5 1.4 智能车制动控制系统设计方案的研究现状 . 7 1.5 本文主要研究内容 . 7 第二章 智能车制动控制系统设计 . 8 2.1 执行机构设计 . 8 2.1.1 设计任务及要求 .
