【作者】 蔡亚光；

【导师】 于文华；

【作者基本信息】 北京林业大学 ， 机械设计及理论， 2013， 硕士

【摘要】 近年来,森林火灾频繁发生,森林消防装备尤其是森林消防车的研制日益受到人们的重视。森林消防车由原来的单一简单化逐渐向种类多样化、功能具体化发展,因而对森林消防车性能的要求也越来越高。森林扑火运兵车作为运送森林扑火人员和装备的专业车辆,不仅要求具有良好的通过性能,也要求具有比其他类型森林消防车辆更好的行驶平顺性能。本文以多体系统动力学为理论基础,以前后均为钢板弹簧非独立悬架的某森林扑火运兵车为研究对象,首先介绍了汽车平顺性的评价方法,并按照国家有关汽车平顺性试验的相关技术要求,在试车场进行了公路道路和林区道路条件下的实车平顺性试验,试验结果显示,在两种路面条件下车身座椅位置的总加权加速度均方根值分别为0.854m/s2和1.797m/s2,森林消防车在林区路面条件下行驶时车辆的平顺性亟待改善。进而采用该车的实际结构参数,在虚拟样机仿真分析软件ADAMS中建立了整车各子系统模型,主要包括前后悬架、车身底盘、轮胎、转向系等,进而装配成整车多体动力学仿真模型,其中对钢板弹簧非独立悬架的建模进行了重点介绍,并对建模原理和过程进行了详细阐述。在此基础上进行了车辆悬架的偏频试验与仿真,验证了整车模型的正确性。然后分析了悬架对车辆行驶平顺性的影响,并以前后悬架刚度和减振器阻尼系数为设计变量,森林消防车驾驶员座椅底板处的总加权加速度均方根值最小为目标函数,对悬架中的弹性元件和阻尼元件进行参数优化设计。最后对优化后的模型进行了A级和F级路面条件下的行驶平顺性仿真,仿真结果表明,车身座椅位置的总加权加速度均方根值分别减小为0.684m/s2和1.263m/s2,森林消防车的行驶平顺性得到了一定改善。更多还原

【Abstract】 In recent years, forest fires occur frequently, the development of forest fire-fighting equipment especially forest fire vehicle has been paid more and more attention to by people. Forest fire trucks have developed from single simply to functional diversification. So the need of its quality has been higher and higher. As a sort of professional vehicles which deliver forest fire personnel and equipment, forest fire suppression personnel carriers not only require good through performance, but also require more greatly riding comfort than other types of forest fire vehicles.Based on multi-body system dynamics theory, this paper was taking forest fire suppression personnel carriers as the research object. The front and rear suspension consisted of the longitudinal leaf spring. First, the evaluation method of vehicle riding comfort was introduced and the riding comfort test was held under the highway road and forest road in the testing field according to the relevant technical requirements. The total weighted RMS acceleration value located under the driver’s seat were respectively0.854m/s2and1.797m/s2.The results showed that the riding comfort of forest fire vehicle needs to be improved when driven through the forest pavement. Then with the vehicle’s actual structure parameters, the vehicle multi-body dynamics simulation model was established in the virtual prototype simulation analysis software ADAMS, including front and rear suspension system, chassis system, tires system, power transmission system, braking system, steering system, etc. The modeling of the steel plate spring independent suspension was emphasized, and the modeling principle and process were introduced in detail. The test and simulation for partial frequency of suspension was carried on, which verified the validity of the whole vehicle model. Then the effects of the suspension on ride comfort of the vehicle was analyzed, and the function, which took the front and rear suspensions’stiffness and absorbers’damping as design variables and the total weighted RMS acceleration value located under the driver’s seat as the target variable, was established to optimize the design of elastic elements and damping elements in suspension. Finally, the riding comfort simulation for the optimized model was conducted under A grade and F grade road surface conditions, the simulation results showed that the total weighted RMS acceleration value was reduced to0.684m/s2and1.263m/s2, the riding comfort was improved.更多还原