机械设计外文翻译-小车的动态模型和动态桥式起重机的仿真 【中文2260字】【PDF+中文WORD】

机械设计外文翻译-小车的动态模型和动态桥式起重机的仿真 【中文2260字】【PDF+中文WORD】,中文2260字,PDF+中文WORD,机械设计,外文,翻译,小车,动态,模型,桥式起重机,仿真,中文,2260,PDF,WORD 【中文2260字】 小车的动态模型和动态桥式起重机的仿真 摘要 根据小车的结构和工作桥式起重机的特点，本文建立了双摆系统动态模式的车时起点。并利用亚当斯进行动力学仿真，得到悬重的偏角和钢丝绳的横向张力，随时间变化，主要因素是小车的钢丝绳长度对启动加速度的大小有影响。当吊车开始广泛得到运用，它实现一个真正的动态特性。 关键词：桥式起重机 吊车 双摆 动态模型 动态仿真 引言 小车起重机系统的最大特点是开始和工作时制动频繁。在开始和突然刹车时，起重机机械系统会产生强烈的冲击和振动。这种冲击和振动会带来整个系统的动态负载，使货物摆动。越小的动态负载，货物摆动范围越小。所以起重机可以更稳定地工作，并具有更长的使用寿命。因此，研究小车起重机系统在启动的动态响应和制动工况具有重要的工程意义。本文重点介绍了小车的动力学特性在启动条件。目前，小车的动态模型在启动条件下是单摆的动态模型，这是根据实际起吊货物作业的小车不同而变化。在这篇文章中，双摆动力学数学小车在启动工况模型建立和全面的动态仿真结束考虑到小车的实际操作中，从三个绳货物的悬浮液的长度的各方面，从小车吊钩悬挂点的绳子长度的货物，具有加速度的小车，并对该小车在开始的时候的效果运行条件的摆动角度进行了研究发现这是随时间变化的横拉的过程。 双摆动力学小车的数学模型 桥式起重机起吊货物的小车显示在图1中： 1-货物2-挂钩3-滑轮组4-钢丝绳5-小车6-主梁 其中M0是商品的质量，M1是质量总和钩子和滑轮，M2是小车的总质量，Q是电动机起动时的驱动力的转换，L1为绳索悬挂物品的长度，L是线的长度绳子从悬挂点到钩，a1为摆动绳与垂直方向钢丝绳的相比，当开始a2为货物的摆动角度与垂直相比方向开始的时候，不计空气阻尼的影响，忽略钢丝绳的质量，绳子的长度保持不变。不包括空气阻尼的影响，忽略钢丝绳的质量，绳子的长度保持不变。所以根据特性小车系统的结构和工作，小车可以实现该系统，双摆动力学小车在开始工作的数学模型条件成立，示于图2。 图2 双摆动力学数学小车在启动工作状态模型图 小车的动力学方程 对于小车，在启动过程中，X2是M2的水平方向的位移，X1是M1的水平方向的位移，X0是M0的水平方向的位移，ƒ是摩擦阻力，建立平面直角坐标系，图2中的M0和M1在坐标系中列如下方程： 因为α1和α2是非常小的，因此它们可以近似为：α1≈sinα1 α2≈sinα2 cosα1≈1 cosα2≈1 系统的总动能如下： 该系统的总能： 使用第二拉格朗日方程，可以得到小车的在开始工作双摆系统的动力学方程如下： 从通过式（1）（3）我们可以看到，部分角a1和a2的主要影响因素是货物M0，滑轮和吊钩的质量M1，钢丝绳的长度，悬挂物品的L1，绳子的长度挂钩商品 L2，小车加速X2。进一步的分析表明，在这些因素中，L1，L2和X2起主要影响。 模拟与小车的分析 本文使用了一个50t/10t双梁起重机，M5的工作层面，例如。该参数如下：该移动电机类型是YZR160M2-6，功率为8.5KW，转速为双速930r/min;齿轮减速器的传动比为37.9，率钢丝绳为10;鼓的直径为400mm，钢丝绳直径为24毫米;小车的速度均匀是640毫米/秒。因为钢丝绳的速度是10，模拟条件是，钩可以提升5吨货物。 首先，我们使用SolidWorks构建桥式起重机的相关三维模型，然后输入简化模型导入ADAMS。确定货物的相关运动，包括钢丝绳是由分立的柔性的组成部分组成。终于得到了桥式起重机的工作模式在虚拟三维仿真环境。如图3所示： 图3 台车的模型在ADAMS中 通过计算，小车的起始时间为3.2s。仿真时间取为10s，仿真步长为200mm。因为钢丝绳的税率为10，使用密度有偿提供方法来设定权重5t。仿真步骤和仿真分析如下： 1）L2的影响。取L1为2.5m，平均加速度为0.2m/ s2中。取L2为0.5m，1m，1.5m。从仿真结果（角的图略），随着L2的增加，我们可以知道α1，α2只增加很小，随着L2的增加。所有这些影响相当于较小的尺寸，但是对α1和α2的振荡频率的影响很大。 2）L1的影响。取L2为0.5m，平均加速度为0.2m/ s2。取L1为2m，2.5m，3m做动态模拟。从模拟（角的数字是省略）每次增加L1。α1每次增加0.25度。α2每次分别增加0.25度和0.1度。伴随着增长大于L2，α1和α2的振荡频率降低了L。 3）从影响汽车的加速的水平拉力的钢丝绳的角度。综合上述结论，取L1为2m，L2为0.5m做动态模拟。图4示出在模拟条件下的轿厢速度线图。汽车的正常运行速度是640mm/s。红色实线示出，实现了时间的正常运行速度为3.2s，所以启动平均加速度为0.2m/ s2，假设它为α1。蓝色虚线表示，实现了时间的正常运行速度为2.5s，因此起始平均加速度为256mm/ S2，假设它为α2。 图4 车速图 图5，图6示出的角度（α1和α2）改变两个不同的加速度（α1和α2）的示意图。通过仿真图形分析，汽车的起动加速度增大，并且角α1和α2也增加了。当汽车的平均加速度从200mm/ S2增大到256mm/s2，α1增加了0.5度和α2增加0.75度。从该仿真结果分析，角在汽车起步加速和增加与轿厢加速度而振荡频率对轿厢的加速度小的影响下有很大的影响。 α1的加速度 α2的加速度 图5在不同的加速度下改变α1 α1的加速度 α2的加速度 图6在不同的加速度下改变α2 图7显示在不同加速度下钢丝绳横向张力的变化规律。从仿真结果中，我们可以知道，随着启动加速度的增加，钢丝横向绳张力增加了约750N。在启动过程中，这是具有明显增加的水平移动荷载。因为这个摆是由动态负载带来的，在正常的速度下小车出现小幅度波动。 图7 横向钢丝绳张力 结论 研究了摆动角度和动态特性具有重要意义，提高了起重机的工作效率和稳定性。本文采用了当小车启动时用ADAMS模拟摆动角度以及重物的动态特性。从仿真中，首先我们可以知道，L1和L2的大小对摆动频率有较大影响，它们具有更大的长度，更大的摆动角度。其次，摆动角的大小和水平动态负载对小车的加速度具有更大的影响，并且随着增加小车的加速度二者将不断增加。 The Trolleys Dynamic Model and Dynamic Simulation of the Bridge Crane Xiangdong Li,Xucheng Yuan,Chao Zhou,Xu Chen Jiangsu Institute of Special Equipment Safety Supervision and Inspection Nanjing,China Shuishui Li,Yuanxun Fan Nanjing University of Science and Technology Nanjing,China AbstractAccording to the trolleys structure and working characteristics of bridge crane,this paper has established the double pendulum dynamic system mode when the trolley is starting.And it also use ADAMS to proceed this dynamic simulation,then get the hanging heavys partial angular and the wire ropes horizontal tension that changes with time of history,find the main factor-the length of the wire rope and trolleys start-up acceleration that influence the angles size.It realizes a true dynamic characteristic when the trolley is starting.Keywords-bridge crane;trolley;double pendulum;dynamic model;dynamic simulation I.INTRODUCTIONThe biggest characteristic of trolley crane system is starting and braking frequently when working.In the moment of starting and braking frequently and suddenly,the crane mechanical system will have a strong impact and vibration.This shock and vibration will bring the whole system the dynamic load,and make goods swing.The smaller the dynamic load is,the smaller the range of goods swing is.So the crane can work more stably and have longer life.Therefore,the study of the dynamic response of trolley crane system in the starting and braking condition has important engineering significance.This paper focuses on the dynamics characteristic of the trolley in start conditions.At present,the dynamic model of the trolley in start condition is single pendulum dynamic model,which is different from the actual lifting goods operation of the trolley.In this article,the double pendulum dynamics mathematical model of the trolley in the start working condition is established and the dynamic simulation is finished with fully considered the actual operation of the trolley,From three aspects of the length of rope for the suspension of goods,the length of rope from trolley hook suspension point to goods,the acceleration of the trolley,the effect of the trolleys start running condition to the swing angle is researched and the process of the horizontal pull which is changed with time is found.II.THE DOUBLE PENDULUM DYNAMICS MATHEMATICAL MODEL OF THETROLLEYThe trolley of the bridge crane lifting with goods is shown in figure 1:Figure 1 trolley 1-goods 2-hook 3-pulley block 4-wire rope 5-trolley of bridge crane 6-main girder Where 0mis the quality of goods,1mis the quality sums of the hook and the pulley,2mis the trolleys total mass,Q is the driving force conversion of the motor when starting,1Listhe length of rope for hanging goods,2L is the length of wire rope from the suspension point to the hook,1?is the swing angle of wire rope compared with vertical direction when starting,2?the swing angle of goods compared with vertical direction when starting,Excluding the effects of air damping,ignoring the quality of steel wire rope,and the rope length remains unchanged.So according to the characteristics of the trolley systems structure and work,trolley can travel under the and of the system,the double pendulum dynamics mathematical model of the trolley in the start working conditions is established which is shown in Figure 2.?Figure 2 the double pendulum dynamics mathematical model figure of the trolley in the start working condition Quality and Technical Supervision Bureau of Jiangsu,KJ103708_ 978-1-61284-441-1/11/$26.00 2011 IEEE 216III.DYNAMIC EQUATION OF THE TROLLEYFor the trolley,where 2x is the displacement of 2minstart-up process,1xis the horizontal displacement of 1min the start-up process,0 xis the horizontal displacement of 0min the start-up process,f is the friction resistance during the start-up process.Establish plane Cartesian coordinate system,as shown in figure 2 is 1mand0m position respectively in the coordinate system are as follows:1211111sincosxxLyL?And 02112201122sinsincoscosxxLLyLL?Because1?and 2?are very small,so it can be approximated into:112212sin,sin,cos1,cos1?The total kinetic energy of system is as follows:222212211100222022121212222211021211122222121222111)222 11)(222 1)22 22Em xm xymxym xm xL xLm xL xLL xL LL?The systems total potential is:(1 cos)(coscos)21110121122Em gLm g LLLL?Using the second Lagrange equation,can get the trolleys starting work double pendulum dynamics system equation as follows:221121110120110122111011 0m L xm Lm L xm Lm L Lm gLm gL?1?221211102011022m xm xm Lm xm Lm LQf?2?202212122022()0m L xL LLm gL?3?From type(1)through(3)we can see that the major influence factors of the partial angle1?and 2?is the quality of the goods0m,the quality of pulley and hook1m,wire ropes length of suspension goods1L,ropes length from hooks to goods2L,acceleration of trolley2x?.Further analysis shows that in these factors,1L,2Land 2x?plays a main influence.IV.SIMULATION AND ANALYSIS OF TROLLEYThe paper has used a 50t/10t double girder crane with M5 working level for example.The parameters are as follows:The moving motor type is YZR160M2-6,power is 8.5KW,rotate speed is 930r/min;Transmission ratio of gear reducer is 37.9;Rate of wire rope is 10;Diameter of drum is 400mm;Diameter of wire rope is 24 mm;The trolleys uniform speed is 640mm/s.Because of rate of wire rope is 10,simulation conditions is that hook takes full lifting 5t goods.Firstly we use SOLIDWORKS to build the bridge cranes related 3d model,and then input the simplified model into ADAMS.Define related movement of goods,including the wire rope which is composed by discrete flexible components.Finally get the bridge cranes working model in virtual 3d simulation environment.Figure 3 shows:Figure 3 trolleys model in ADAMS Through calculation,the trolleys starting time is 3.2 seconds.The simulation time is taken as 10s,simulation step length is 200.Because rate of wire rope is 10,use available compensational method of density to set the weight for 5t.Simulation steps and the simulation analysis are as follows:1)The influence of2L.Take 1L for 2.5 m,the average acceleration is 0.22/m s.Take 2L for 0.5m,1m,1.5m.From the simulation results(the angles figure is omitted),we can know1?,2?all increase only tiny along with the increase of2L.The size of them all influenced relatively small,but the oscillation frequency of 1?and2?are influenced larger.2)The influence of1L.Take 2L for 0.5m,the average acceleration is 0.22/m s.Take 1L for 2m?2.5m?3m to do dynamic simulation.From the simulation(the angles figure is 217omitted)that with the twice increasing of1L.1?every time increased 0.25?.2?every time increased 0.25?and 0.1?respectively.Growth is greater than their influence about2L.And the oscillation frequency of 1?and 2?also decreases with the increasing of 2L.3?The influence of angular and the horizontal tension wire rope from car acceleration.Comprehensive the foregoing conclusion,take 1L for 2m,2L for 0.5m for dynamic simulation.Figure 4 shows the car velocity diagram in simulation conditions.The normal operation speed of the car is 640mm/s.The red solid line shows that achieving the normal operation speed of time is 3.2s,so the starting average acceleration is 0.22/m s,assuming it as 1a.Blue dashed said that achieving the normal operation speed of time is 2.5s,so the starting average acceleration is 2562/mm s,assuming it as 2a.Figure 4 Vehicle speed diagram Figure 5,figure 6 shows the angle(1?and 2?)changing diagram of the car in the two different acceleration(1a and 2a).By the simulation graphics analysis,the start-up acceleration of car increased,and the angular 1?and 2?also increased.When the car average acceleration from 2002/mm s increases to 2562/mm s,Angular1?increased 0.5?and angular 2?increased 0.75?.From this simulation result,angular has great influence on the car start-up acceleration and increases with the increasing of car acceleration while oscillation frequency has small influence on car acceleration.Acceleration is 1a Acceleration is 2aFigure 5 changing rules of 1?in different acceleration Acceleration is 1a Acceleration is 2aFigure 6 changing rules of 2?in different acceleration Figure 7 shows the horizontal tensions changing rule of wire rope in different acceleration.From the result of simulation,we can know that the horizontal tension of wire rope has increased about 750N along with the increase of start-up acceleration.It also has obviously increased the horizontal moving load of the start-up process.And because of this swing which is brought by the dynamic load,the normal speed of the trolley appears slight fluctuations.Figure 7 the horizontal tension of wire rope V.CONCLUSIONResearch the swinging Angle and dynamic characteristics of the heavy has great significance to improve the cranes working efficiency and steadiness.The paper has used ADAMS to simulate the swinging Angle and dynamic characteristics of the heavy when the trolley is starting.From the simulation,firstly we can know that the size of 1L and 2Lhas bigger influence to the swinging frequencies.The bigger length they are,the bigger swinging angle it is.Secondly,the trolleys acceleration has bigger influence to the size of swinging angle and the horizontal dynamic load.And both of them will be increased while the increasing of the trolleys acceleration.REFERENCES1Raymond Manning,Jeffrey Clement,Dooroo Kim,William Singhose,“Dynamics and Control of Bridge Cranes Transporting Distributed-Mass Payloads,”Journal of Dynamic Systems,Measurement,and Control,vol 132,pp.18,January 2010 2Dooroo Kim,William Singhose,“Performance studies of human operators driving double-pendulum bridge cranes,”Control Engineering Practice 18(2010),pp.567576 3Zongwu Hu,Yisong Yan,“crane dynamics,”Machinery industry press,1988 4Zhiweng Zhang,Heqian Yu,Jingnuo Wang,“Crane design manual,”China railway publishing house,1998 5Zenggang Li,“ADAMS introductory explanation and examples,”Defense industry press,2006 6Zeqiang Zhang,Wenming Cheng,“Bridge type crane heavy dof angular model and simulation,”Southwest jiaotong university journal,2006,41(6)pp.696699 218