A Model for Determining Rider Induced Energy Losses in Bicycle Suspension Systems

The energy dissipated by the suspension systems used for off-road bicycles is a major concern due to the limited power source in cycling. Rider induced energy losses are those that arise from the muscular action of the rider. The purpose of this study was to develop and verify a dynamic model of a seated cyclist riding an off-road bicycle up a smooth road. With the absence of terrain irregularities, all suspension motion was rider induced. Knowing the stiffness and dissipative characteristics of the suspension elements, the power dissipated by the suspensions was calculated.

Simulation results were compared to suspension deflections that were experimentally measured for a cyclist riding a commercially available dual suspension bicycle up a 6% grade at 6.5m/s. For this particular case, no fork motion was observed in the experiments which was consistent with the simulation results. For the rear suspension, the mean and amplitude of the largest harmonic were experimentally determined to be 6.6 and ±2.7 mm respectively. Simulation results were within 0.7mm of the mean and within 0.3mm of the amplitude. The only major discrepancy between the experiments and the simulations was the presence of a phase lag in the simulation results which was attributed to inter-subject variability. The power dissipated by the rear suspension was calculated to be 6.9 Watts or 1.3% of the total power input by the rider. Given the grade and forward velocity, this translated into an equivalent mass of 1.8 kg. Thus, the bicycle appeared to be roughly 12% heavier than it actually was.     

某重型越野汽车驾驶室后悬置有限元分析及改进

本文以ANSYS软件为工具,对某型号越野汽车驾驶室后悬置支架进行受力分析,详细准确地确定了汽车驾驶室后悬置支架的受力情况和应力分布部位,依托分析结果对支架结构进行优化,达到降低驾驶室后悬置支架关键部位应力的目的,并通过实际试验进行验证,结果显示优化后的支架有效地改善了关键部位的应力,解决了支架断裂问题,提高了整个驾驶室悬置系统的可靠性能。     

A Multibody Model for the Simulation of Bicycle Suspension Systems

The paper describes a two-dimensional mathematical model for the motion of a bicycle-rider system with wheel suspensions. It focusses on the prediction of vibrational stress on the rider due to uneven track. The model was evaluated by comparing its predictions with measuring data concerning weighted accelerations on the human body, depending on various bicycle designs and road surfaces. For the intended purpose the predictions for vibrational stress and vibrational behaviour are sufficiently precise, and the model turns out to be adequate for designing and developing bicycle suspensions.     

越野摩托车后摇臂铝合金技术的应用

改进后的铝合金后摇臂,材料为6061-T6,采用TIG焊接工艺,焊接后进行T6热处理,表面抛光氧化处理;经整车8 000次跌落试验,后摇臂未断裂,达到了设计标准,提高了企业在国内外市场的竞争力,给企业带来了巨大的经济效益。     

轻型越野车车轮定位与悬架的相互影响

分析了轻型越野车采用悬架系统相应的车轮定位特性,通过对侧倾中心和车身侧倾角的分析,得出了车轮定位与悬架相互影响的工程理论研究方法,并通过ADAMS仿真分析和道路试验给予了验证。     

某款越野车后摆臂折弯分析

利用有限元分析法对越野车后摆臂进行设计,并在设计完成后运用道路耐久试验、跳跃试验等多种手段进行强度验证是非常有必要的,它可以预测并发现后摆臂设计时的强度问题,再利用优化设计进行避免。     

多连杆后悬架托臂强度分析

针对某一轿车行驶6400公里左右时,后悬架托臂出现开裂的现象。本文采用有限元方法,用 Hypermesh软件对后悬架托臂的CAD模型进行有限元网格划分、ABAQUS为求解器,对托臂进行不同工况下的强度校核,根据托臂的应力分布情况来分析断裂的原因,并提出改进方案,为托臂的前期设计提供一种方法。     

一种轻型载货车后悬架的设计

针对轻型载货车的悬架设计,提出一种有效的设计方案。该方案包括弹性元件和阻尼元件的设计过程。同时对设计方案进行了仿真分析及台架试验,以检验方案的可靠性。汽车悬架系统作为保证车轮或车桥与汽车承载系统之间具有弹性联系并能传递载荷、缓和冲击、衰减振动以及调节汽车行驶中的车身位置的装置,对整车性能指标很大的影响。     

用筒系吸能结构改进横梁的缓撞性能

基于圆管的吸能原理，采用铝质筒元作为吸能元件，研究筒元轴向与径向承载的不同变形模式，以及不同排列方式筒系结构对被撞横梁的缓冲性能的改善效果。试验和模拟计算结果表明，筒系吸能结构能明显降低与横梁碰撞的台车的减速度值，提高横梁的能量吸收能力，缓冲效果显著。     

微型电动汽车后悬架设计

在当今社会,汽车已经发展成人们日常生活中的代步工具,更快更舒适成为了今后汽车的研究方向,因此悬架系统成为了人们首要的研究目标.本设计以两座电动汽车后悬架为研究对象,通过对两种类型的悬架的优缺点进行对比,选取最适合两座电动汽车后悬架的悬架类型,采用非独立悬架以达到制造简便、方便维修且结构简单的目的.对后悬架的弹性元件和减...     

越野车复合型悬架平顺性的研究

为解决越野车在复杂路面行驶过程中平顺性较差的问题,本文中在某型越野车原悬架系统上加装空气弹簧,形成新型复合型悬架结构.首先为探究越野车悬架系统的振动机理,通过对越野车空气弹簧和原悬架系统进行理想化结构分析,构建出了空气弹簧与螺旋弹簧相并联的复合型悬架系统模型;然后针对越野车行驶要求,提出了一种新型工作模式切换控制策略,...     

越野车油气悬架的建模与试验研究

在考虑沿程压力损失、局部压力损失和活塞杆与密封装置间的动摩擦等情况下,建立了某越野车用油气悬架非线性模型。通过仿真,研究阻尼阀系的参数对油气悬架阻尼特性的影响。结果表明,在其他参数不变的情况下,可通过更换具有不同锥角的阀芯,方便地获得不同的阻尼特性。仿真结果与试验数据基本吻合,验证了所建油气悬架数学模型的正确性。     

扭转梁式半独立后悬架系统开发

在扭转梁式半独立后悬架系统开发时,需要设计师平衡各种利弊因素,通过优化方法来达到预先设定的性能.扭转梁的剪切中心、横梁截面、扭转刚度以及悬架运动特性的确定是这种类型悬架设计的关键点.     

五连杆非独立后悬架侧倾性能研究

运用动静法创建了稳态回转时五连杆后悬架的侧倾平面模型运动方程,运用矢量几何法分析了车体侧倾角和横向推力杆方向角之间的关系。通过对某SUV车实例分析,得出了不同的几何位置下车体侧倾角、有效侧倾刚度及侧倾中心位置的变化。结果表明,当车辆稳态回转时,横向推力杆的长度及方向角、上拉杆的布置对悬架的侧倾特性有重要影响;仿真结果与道路试验结果在趋势上有较好的一致性。     

后前束连杆强度设计

提高后前束杆的强度,能降低交通事故的发生,文章从结构力学计算和CAE强度分析着手,找出了某双连杆后独立悬架前束连杆断裂的原因,并提出将双头螺栓的结构改进为六角套管的设计方案.台架试验结果表明,改进后的前束连杆,强度相对原设计提升1倍,疲劳强度大幅提升,为解决此类问题提供参考.     

提高某越野运兵车乘坐舒适性的悬架设计

文章针对某越野运兵车,通过对悬架系统的结构和零部件进行改进设计,来提高运兵车的乘坐舒适性。     

扭力梁式后悬架对不足转向性的影响分析

根据汽车操纵稳定性理论和悬架侧倾受力分析,较系统地阐述了扭力梁式后悬架对整车不足转向性的影响和改善措施。通过对前束和轴转向的控制,使后轴车轮侧偏角背离整车离心力方向,以提高整车的不足转向性。     

某军用越野巡逻客车后门锁失效分析及改进设计

某军用越野巡逻客车在特别恶劣的路况行驶时,会出现后门自动打开现象.本文分析该故障原因,并进行结构改进及试验验证.     

前期整车后悬架硬点优化设计

在某车型后悬架硬点前期开发中,确定了整车后悬架硬点设计开发以悬架KC特性作为优化设计工况。基于工程经验和四连杆式悬架特点,选择对悬架KC特性有较大影响的悬架设计参数,通过对比分析,选用合适的DOE方法、近似模型法和优化算法,实现了整车后悬架硬点的优化设计,提高了整车开发效率。     

Optimal Preview Control of Rear Suspension Using Nonlinear Neural Networks

SUMMARY

The performance of neural networks to be used for identification and optimal control of nonlinear vehicle suspensions is analyzed. It is shown that neuro-vehicle models can be efficiently trained to identify the dynamical characteristics of actual vehicle suspensions. After trained, this neuro-vehicle is used to train both front and rear suspension neuro-controllers under a nonlinear rear preview control scheme. To do that, a neuro-observer is trained to identify the inverse dynamics of the front suspension so that front road disturbances can be identified and used to improve the response of the rear suspension. The performance of the vehicle with neuro-control and with LQ control are compared.