【作者】 李芳；

【导师】 赵丁选；

【作者基本信息】 吉林大学 ， 机械电子工程， 2017， 硕士

【摘要】 悬架是汽车的一个重要核心组成部分,它是传输车轮力和力矩的装置,直接影响着汽车的行驶性能。较为传统的被动悬架结构简单成本较低,但在设计过程中面临着参数优化匹配的问题,同时无法保证车辆在行驶过程中保持最佳性能状态。而可以使车辆保持较好行驶性能的主动悬架能量消耗又非常大,因此开发兼具被动悬架和主动悬架优点的悬架系统具有重要的意义。本文所设计的悬架系统可以在路况较好的路面上使用被动状态,路况较差时使用主动悬架系统以降低振动,因此也越来越受到人们的关注。本文结合结合国家重点研发计划课题“高机动应急救援车辆(含消防车辆)专用底盘及悬架关键技术研究”(2016YFC0802902)和吉林省汽车产业发展专项资金项目—“轿车惯性调控主动悬架研制开发”(20112330),在参考国内外优秀文献的基础上,以课题自制的悬架样车为研究对象,对悬架系统被动状态系统的弹簧减震器参数进行了匹配优化,并在参数优化后基础上开展主动状态的控制器开发研究工作,并对开发设计的悬架系统进行了仿真试验和实车路面试验。首先,搭建模型。根据悬架的物理运动学模型,选择适当的状态变量,建立了汽车悬架系统的状态方程,并在考虑汽车前后轮时间滞后性和左右轮的相干性基础上建立了随机路面模型。其次,优化参数。为了提高车辆被动状态下的汽车性能并正确地评价之后建立的主动悬架性能,设计出改进型遗传算法对悬架参数进行了优化,提高了被动状态下的汽车性能,参数优化后的悬架系统的垂向加速度均方根值、俯仰角加速度均方根值和侧倾角加速度均方根值相对于理论参数分别降低了16.9%、23.08%、16.58%。第三,设计了主动悬架控制器。为了提高车辆在主动状态下汽车性能,本文在参数优化后的基础上设计了基于卡尔曼滤波的最优控制算法。为了使最优控制器能够得到更好的效果,本文使用了卡尔曼滤波器对悬架的状态进行估计修正进而供最优控制器使用,这样可以大大提高反馈的准确性,并减少了悬架系统的传感器个数降低了成本。设计的主动悬架系统的三个前述加速度均方根值分别降低了45.68%、51.51%、59.78%。最后,进行样车实验。为了更有力地说明设计出的悬架系统的效果,将设计开发出的主动悬架控制器安装在自行研制的试验样车上进行了实车验证试验。试验结果显示,设计开发的主动悬架控制器确实可以提高整体车辆的行驶性能。更多还原

【Abstract】 All the power and torque transmission between the car’s body and the wheel is done by the car suspension system.That is to say,the force and torque that the road give are transmitted through the suspension system to the body.The suspension system can absorb and attenuate the impact of uneven road surfaces,attenuates the vibration caused by the elastic system,to ensure the normal driving of the vehicle handling stability,ride comfort and driving safety.Because of the complex of road conditions,the traditional passive suspension has been difficult to meet people’s comfort and safety requirements,while the complete active suspension energy consumption is very large,therefore,it is of great significance to develop a switchable suspension system with both active suspension and active suspension.The switchable suspension system can use passive conditions on good road conditions,and use active suspension systems to reduce vibration when the road conditions are poor,and are therefore more and more concerned by people.This article relies on Jilin Province automobile industry development special fund project-" research and development for active suspension with inertia control active"(20112330),by reading the excellent literature at home and abroad and using the self-made suspension model vehicle as the study object,the paper matched and optimized the parameters of the system.And then design the controller of active suspension system.At last,the paper conducted a simulation test and a real road test.Firstly,based on the physical kinematics model of the suspension,the appropriate state variables are selected to establish the state equation of the vehicle suspension system.A random pavement model is established based on the time lag of the front and rear wheels and the coherence of the left and right wheels.Then,in order to improve the performance of the vehicle under the passive state of the vehicle and evaluate the active suspension performance,the improved genetic algorithm is designed to optimize the suspension parameters to improve the performance of the vehicle under the passive state.The root mean square values of thevertical acceleration,pitch angle acceleration and roll angle acceleration of the system are 16.9%,23.08% and 16.58% respectively lower than the theoretical parameters.At the same time,in order to improve the performance of the vehicle under the active condition,the optimal control algorithm based on Kalman filter is designed based on the parameter optimization.In order to make the optimal controller get better results,this paper also uses the Kalman filter to estimate the state of the suspension and then for the optimal controller to use,which can greatly improve the accuracy of the feedback and reduce the number of sensors in the rack system,so that can reduces the cost.The three root mean square values of the active suspension system are reduced by 45.68%,51.51% and 59.78% respectively.Finally,in order to more effectively illustrate the design of the suspension system effect,will be designed to develop the active suspension controller installed in the test prototype on a real vehicle test.The results show that the active suspension controller designed and developed can improve the performance of the suspension system.更多还原