The Influence of Structural Flexibilities on the Straight-running Stability of Motorcycles

SUMMARY

A new tyre model for studies of motorcycle lateral dynamics, and three new motorcycle models, each incorporating a different form of structural compliance, are developed. The tyre model is based on “taut string” ideas, and includes consideration of tread width and longitudinal tread rubber distortion and tread mass effects, and normal load variation. Parameter values appropriate to a typical motorcycle tyre are employed. The motorcycle models are for small lateral perturbations from straight running at constant speed, and include (a) lateral compliance of the front wheel in the front forks, (b) torsional compliance of the front forks, and (c) torsional compliance in the rear frame at the steering head about an axis perpendicular to the steering axis.

Results in the form of eigenvalues, indicating modal damping properties and natural frequencies are presented for each model. The properties of four large production machines for a range of forward speeds, and the practicable range of stiffnesses are calculated, and the implications are discussed.

It is concluded that typical levels of structural compliance in models (a) and (c) contribute significantly to the steering behaviour properties of large motorcycles, and their observed behaviour can be understood better in terms of the new results than of those existing previously. Some conclusions relating to optimal structural stiffness properties are also drawn.     

回火工艺对摩托车零部件质量的影响

回火工艺是摩托车零部件热处理的最后一道工序,因而被大多数人认为是相对简单的过程。但是从现场发生事故的频率来看,回火是一个特殊的过程,必须有效地加以控制,它的质量特性在产品服役过程中才能表现出来,无法实际检测。回火特殊过程的特点是连续生产、批量投入,一旦出现热处理质量问题,对整个生产影响很大。     

结构参数对三塔悬索桥空气动力稳定性的影响分析

以在建主跨为1080m的三塔双跨悬索桥--泰州长江公路大桥为工程背景,采用三维非线性空气动力稳定性分析方法,分析主缆矢跨比、加劲梁恒载集度、加劲梁支承方式、中塔型式、缆索体系等结构参数对三塔悬索桥空气动力稳定性的影响,并探讨了具有良好抗风稳定性的三塔悬索桥的结构布置形式.结果表明:三塔悬索桥主缆的矢跨比在1/10～1/11范围内,主梁跨中设置刚性中央扣,增强中间桥塔的纵桥向刚度以及采用空间缆索体系或平面双缆体系时,可以获得较好的空气动力稳定性.     

地铁施工对某饭店裙楼结构稳定性影响分析

为了解由于地铁施工引起的建筑物总体沉降、不均匀沉降的大小以及相应的附加应力分布,并进一步对裙楼结构和安全性做出评价,从而减小或避免其造成的影响,以某饭店裙楼为研究对象,通过ANSYS有限元数值模拟,以不同的沉降变形为控制条件,分析地铁施工对该结构稳定性的影响。最后分析该结构变形的原因,给出了保证该结构稳定性的建议。     

不同抽气方式对摩托车排放测试的影响探讨

通过试验对比,采用闭式和开式抽气方式对摩托车工况法排放测试结果均有一定影响,受影响的主要是怠速和15km／h工况。其中闭式抽气方式影响较大,影响程度大小分别是怠速工况,其次是15km／h工况,而在发动机转速较高的32km／h、35km／h和50km／h工况时影响较小。     

论电动摩托车标准对摩托车行业的影响（1）

国家标准管理委员会发布的2009年第8号（总第148号）公告中发布了4项与电动摩托车有关的国家标准,这4项标准从2010年1月1日开始实行。该标准的出台发展和规范了电动摩托车的标准体系,为电动摩托车行业的进一步发展提供了技术支持,本文结合电动车行业和摩托车行业现状及未来技术发展趋势,分析了该标准对摩托车行业的影响。     

论电动摩托车标准对摩托车行业的影响（2）

正是在上述情况下,国家相关部门制定了电动摩托车和电动轻便摩托车的4项标准,但争议较大,争议的焦点集中于电动轻便摩托车的定义。     

The Lateral Dynamics of Motorcycles and Bicycles

SUMMARY

The paper is a review of the state of knowledge and understanding of the steering behaviour of single-track vehicles, with the main accent on vehicle design, and vehicle design analysis and behaviour prediction.

The body of the paper consists of a chronological account of the steps which have been taken in establishing the current position. Scientific study of the motions of two-wheelers has been in progress for more than 100 years, but progress was slow and many conflicting conclusions were drawn until increasing understanding of tyre mechanics, systematic application of the laws of motion for systems of rigid bodies, digital computation and modern numerical methods, and improved mobile measurement, recording, and data processing capabilities allowed the pace to accelerate.

The current position, which is that a good understanding of the relationship between design and performance has been achieved, but that by no means have all the problems of significance been solved, is described at the end of the paper.     

摩托车齿轮的标准化工作

全国摩托车齿轮标准化工作组于2000年元月在郑州成立,并于2000年6月在郑州召开了第二次会议.这是在中汽协会摩托车分会与中国齿轮专业协会共同领导下的标准化工作机构,其任务是:组织制定和审定摩托车齿轮标准,组织宣传及编写相关宣贯资料,跟踪国际标准化的发展与国内产业进步、定期修订摩托车齿轮标准.     

The Lateral Dynamics of Motorcycles and Bicycles

The paper is a review of the state of knowledge and understanding of the steering behaviour of single-track vehicles, with the main accent on vehicle design, and vehicle design analysis and behaviour prediction.

The body of the paper consists of a chronological account of the steps which have been taken in establishing the current position. Scientific study of the motions of two-wheelers has been in progress for more than 100 years, but progress was slow and many conflicting conclusions were drawn until increasing understanding of tyre mechanics, systematic application of the laws of motion for systems of rigid bodies, digital computation and modern numerical methods, and improved mobile measurement, recording, and data processing capabilities allowed the pace to accelerate.

The current position, which is that a good understanding of the relationship between design and performance has been achieved, but that by no means have all the problems of significance been solved, is described at the end of the paper.     

影响摩托车零部件质量的原材料因素

原材料的外观质量、化学成分、低倍组织、脱碳层深度、非金属夹杂物、显微组织(晶粒度)和顶锻试验等7个方面,对摩托车零部件质量的影响均较大。高级优质级别的中碳钢、低中碳合金钢化学成分应达到标准的中上限,且强化元素C、Cr、Mn、Mo等平均含量应高于标准要求的中限。低倍组织中的中心疏松、一般疏松、方形偏析允许≤1.5级,不允许存在白点、缩孔、气泡、翻皮等缺陷。钢材的脱碳层深度应不大于公称直径的1%;显微组织中带状组织0～3级为合格,魏氏组织0～2.5级为合格。摩托车零部件原材料的实际晶粒度应控制在6～8级。     

ODS技术在摩托车振动上的应用

通过对ODS原理的探讨,并在此基础上对摩托车整车进行了ODS试验,提出了降振改进方案。试验表明,运用ODS技术对摩托车整车降振快捷,共振明显消失,振动情况更好,达到了预期目标。     

大阳摩托车三相电气系统的设计

随着摩托车电控、照明及信号等系统性能要求的提高,对整车电气系统的功率要求也相应提高。本文介绍的自行研制的大阳系列大排量骑式车、踏板车、电喷车电源供电系统均由大功率三相磁电机、三相全波调压整流器、免维护大容量蓄电池等组成,能确保整车用电系统电力更充足,电起动、照明和信号等系统工作更可靠。     

缩短研发周期提高开发效率

随着我国摩托车市场竞争的日趋激烈,多数生产企业在经历了持续的价格战和促销战之后,开始逐渐认识到无序竞争给企业带来的巨大损失,纷纷掉转矛头,将主要精力投人到新产品开发上来,并逐步将企业工作的重点由原来的产销转向了产品开发.但是,由于企业产品开发的机制和流程还存在一定的问题,不同程度地存在着新产品开发效率较低,难于得到市场认同等问题.如何用最短的时间开发出市场认可的新产品是企业在激烈的市场竞争中能否制胜的关键.     

摩托车平顺性的道路模拟试验研究

运用谐波叠加法建立了C级路面模型,通过模拟迭代将路面不平时间历程转化为激振器的驱动信号,并应用于道路模拟的摩托车平顺性试验测试中。采用两通道轮胎耦合道路模拟试验机对摩托车系统进行了振动试验,分别对驾驶员座垫、脚踏、手把和行李箱位置的振动加速度进行了测试,测试结果表明,行李箱处的振动最大,手把位置和脚踏位置的振动次之,座垫处的振动最小。