摘要本课题建立了以1/4振动悬架为模型的空气悬架,研究空气弹簧的垂直刚度调节原理以及控制特性,利用了Matlab仿真模型建立了以1/4振动悬架为模型的空气悬架,为了验证最优控制算法的有效性,分别通过对路面白噪声,正弦波路面和锯齿波路面进行仿真,并开发出了空气弹簧的一个电子控制单元。40568
在硬件系统的开发过程中,应用的Protel DXP 2004年完成电路原理图设计使用ATMEL公司的AT8C52单片机当做微处理器,设计时钟设计,滤波放大电路,采样/保持电路,开关电路,输出控制电路。
在系统软件的开发过程中,根据现有的结果的空气弹簧特性,使用结构和模块化的方法,设计一种自适应控制方法,不依赖于精确的数学模型。
控制单元以车体的垂直加速度信号来作为目标量,控制单元接收到由加速度传感器以及加速度信号的快速傅里叶变换由压力传感器信号检测出的压力检测出的加速度信号,并且和已设定好的控制规则来做对比,从而可以得到空气弹簧各种调节方法。,空气弹簧里面的空气的多少会得到改变,经过电磁阀的通、断电。并通过一个步进马达来调节单元的额节流阀口,改变空气弹簧和辅助室之间的空气流动,通过对空气弹簧的刚度以及阻尼进行调整,就可以把空气弹簧调整到适当不错的状态,以实现该空气弹簧的控制。
通过单频激励的实验研究,测试电子控制单元的减振效果,根据所检测的加速度信号和所述压力信号,空气弹簧刚度有效地管理和阻尼提高汽车理想的乘坐舒适性的电子控制单元。
毕业论文关键词:空气悬架;最优控制电控单元;刚度;阻尼
ABSTRACT The subject was established as a model 1/4 vibration suspension air suspension, air spring vertical stiffness study adjustment principle and control features, the use of Matlab simulation model of a 1/4 suspension vibration model of air suspension In order to verify the effectiveness of the optimal control algorithm, respectively, through the white noise of the road, sine and sawtooth pavement road simulation and developed air springs an electronic control unit.
During development of hardware systems, the application of Protel DXP 2004 completed the circuit schematic design uses ATMEL Corporation AT8C52 microcontroller as microprocessors, design clock design, filter amplifier circuit, sample / hold circuit, switching circuit, the output control circuit.
In the system software development process, according to the results of existing air spring characteristics, the use of the structure and modular approach to design an adaptive control method does not rely on precise mathematical models.
Control unit to the vehicle body vertical acceleration signal to a target amount, the control unit receives a signal detected acceleration by the acceleration sensor and a fast Fourier transform of the acceleration signal pressure detected by the pressure sensor signal, and and has set up The control rules do comparison, the air spring can be obtained various adjustment methods. The air inside the air spring the number will be changed, pass through the solenoid valve, power. And to adjust the amount of the throttle valve by a stepper motor interface unit, changing the air flow between the air spring and the auxiliary chamber, through the air spring stiffness and damping adjustments, we will be able to adjust to the appropriate air springs good state to achieve control of the air spring.
Experimental study of single-frequency excitation, the electronic control unit of the damping test results, according to the detected acceleration signal and said pressure signal, effective management of air spring stiffness and damping to improve vehicle ride comfort ideal electronic control unit. AT8C52单片机车辆空气悬架电子控制单元设计+程序+电路图:http://www.youerw.com/zidonghua/lunwen_38969.html