活塞连杆机构的外文和翻译

1、Modeling and Simulation of the Dynamics of Crankshaft-Connecting Rod-Piston-Cylinder Mechanism and a Universal Joint Using The Bond Graph ApproachAbstractThis paper deals with modeling and simulation of the dynamics of two commonly used mechanisms, (1) the Crankshaft Connecting rod Piston Cylinder s

2、ystem,and (2)the Universal Joint system, using the Bond Graph Approach. This alternative method of for mulation of system dynamics, using Bond Graphs, offers a rich set of features that include, pictorial representation of the dynamics of translation and rotation for each link of the mechanism in th

3、e inertial frame, representation and handling of constraints at joints, depiction of causality,obtaining dynamic reaction forces and moments at various locations in the mechanism, algorithmic derivation of system equations in the first order state-space or cause and effect form, coding for simulatio

4、n directly from the Bond Graph without deriving system equations,and so on. Keywords: Bond Graph, Modeling, Simulation, Mechanisms.1 ModelingDynamics of two commonly used mechanisms, (1) the Crankshaft Connecting rod Piston Cylinder system,and (2) the Universal Joint system, are modeled and simulate

5、d using the Bond Graph Approach. This alternative method of formulation of system dynamics, using Bond Graphs, offers a rich set of features 1, 2. These include, pictorial representation of the dynamics of translation and rotation for each link of the mechanism in the inertial frame, depiction of ca

6、use and effect relationship,representation and handling of constraints at joints, obtaining the dynamic reaction forces and moments at various locations in the mechanism, derivation of system equations in the first order state-space or cause and effect form, coding for simulation directly from the B

7、ond Graph without deriving system equations.Usually the links of mechanisms are modeled as rigid bodies. In this work, we develop and apply a multibond graph model representing both translation and rotation of a rigid body for each link. The links are then coupled at joints based on the nature of co

8、nstraint 3-5. Both translational and rotational couplings for joints are developed and integrated with the dynamics of the connecting links. A problem of differential causality at link joints arises while modeling. This is rectified using additional stiffness and damping elements. It makes the model

9、 more realistic, bringing in effects of compliance and dissipation at joints, within definable tolerance limits.Multibond Graph models for the Crankshaft Connecting rod Piston Cylinder system, and, the Universal Joint system 6, are developed using the BondGraph Approach. Reference frames are fixed o

10、n each rigid link of the mechanisms using the Denavit-Hartenberg convention 7. The translational effect is concentrated at the center of mass for each rigid link.Rotational effect is considered in the inertial frame itself,by considering the inertia tensor for each link about its respective center o

11、f mass, and expressed in the inertial frame. The multibond graph is then causaled and codingin MATLAB, for simulation, is carried out directly from the Bond Graph. A sketch of the crankshaft mechanism is shown in Fig.1, and its multibond graph model is shown in Fig.2. A sketch of the Universal joint

12、 system is shown in Fig.3, and its multibond graph model is shown in Fig.4. Results obtained from simulation of the dynamics of these mechanisms are then presented.1.1 Crankshaft - Connecting Rod - Piston-Cylinder MechanismFig. 1 shows the sketch of the “Crankshaft Connecting rod Piston Cylinder sys

13、tem.”Fig. 1: Crankshaft-Connecting Rod-Piston-Cylinder Mechanism.The individual components are considered as rigid links,connected at joints. The first moving link is the crank,the second link is the connecting rod and the third link is the piston. A frame is fixed on each link. Thus frame 1 is fixe

14、d on link 1, frame 2 on link 2, and frame 3 on link 3. A fixed inertial frame 0, whose origin coincides with frame 1, is chosen. However, it will neither rotate nor translate. C1, C2 and C3 are centres of mass of respective links. The frames are fixed on respective links using the Denavit-Hartenberg

15、 convention 4. Dynamics of the system of Fig. 1 is modeled in the multibond graph shown in Fig. 2. The model depicts rotation as well as translation for each link in the system. The left side of the bond graph shows the rotational part and right part shows the translational part. We restrict any mot

16、ion between the origin of inertial frame O and point on the link 1 that is O1 by applying source of flow Sf as zero. Similarly we restrict any relative motion at point A, distinguished by A1 on link 1 and A2 on link 2, by applying source of flow Sf as zero. The piston which is link 3, is constrained

17、 to translate only along the X0 direction. Translation along Y0 and Z0 direction is constrained by applying source of flow Sf as zero for these components. Differential causality is eliminated by making the K(1,1) element of the stiffness matrix K between link 2 and link 3 as zero. Additional stiffn

18、ess and damping elements used for eliminating differential causality make the model more realistic, bringing in effects of compliance and dissipation at joints, within definable tolerance limits. These viscoelastic elements are represented in the bond graph by using C and R elements. We have a sourc

19、e of effort Se at link 3, which is the pressure force acting on the piston, although this force is also acting only in X direction.Fig. 2: Multibond graph model for the Crankshaft Connecting rod Piston Cylinder system of Fig. 1.1.2 Universal Joint MechanismThe Fig. 3 shows the sketch of the “ Univer

20、sal Joint” mechanism.Fig. 3: Universal Joint Mechanism.It has three rigid links, two are yokes which are attached to rotating shafts and the middle one is the cross connecting the two yokes. The inertial frame is numbered 0,and it is fixed. Frame 1 is on link 1, frame 2 on the cross which is link 2,

21、 and frame 3 on the right yoke which is link 3. Origin of the inertial frame coincides with that of frame 1 of link 1. The links 1 and 2 are connected with each other at two coincident end points points A - A1 on link 1 and A2 on link 2, and B - B1 on link 1 and B2 on link 2. Similarly links 2 and 3

22、 are connected at two points D - D2 on link 2 and D3 on link 3, and E - E2 on link 2 and E3 on link 3. Link 1 rotates about Z axis with respect to the inertial frame. The frame 2 is located at the centre of mass of the link 2. Link 2 rotates with respect to the link 1 in direction Z2 as shown in Fig

23、. 3. Frame 3 also coincides with frame 2 but it is located on the link 2. The frame 3 on link 3 rotates with respect to the link 2, about Z3, as shown in Fig. 3. The bond graph for this system is shown in Fig. 4.Fig. 4: Multibond graph for the Universal Joint system of Fig.The issue of differential

24、causality arises for this mechanism also. It is eliminated using additional stiffness and damping elements. As discussed earlier, this makes the model more realistic, bringing in effects of compliance and dissipation at joints, within definable tolerance limits. The relative motion between the links

25、 at joints, along certain directions, is restrained by applying the source of flow Sf as zero. The constraint relaxation is tuned by changing the values of stiffness and damping at corresponding joints. Here we restrict the motion of the link 3 in two directions Y and Z, and allow motion in X direct

26、ion by resolving the source of flow in three parts and by putting Sf as zero in Y and Z directions only. For the simulation, an excitation torque is applied to link 1 about the Z direction2 SimulationThe results of computer simulation for the crankshaft mechanism of Fig. 1 are discussed first. The i

27、nitial position of the crankshaft is at 1 = 60o with the X0 axis. It is then released under the effect of gravity. The force of gravity also acts on the connecting rod. No force due to gas pressure is considered for the simulation as it is not the main issue under focus for this paper. The upper row

28、 in Fig. 5 shows the displacement of the centre of mass C1, as observed and expressed in Frame 0. It moves in a circular arc about the Z0 axis. The first figure in the lower row of Fig. 5 shows the oscillation of the crankshaftabout the Z0 axis through change in orientation of the unit vectors of Fr

29、ame 1. The second figure in the second row shows the oscillation of the centre of mass C1 with time. This could perhaps be ascribed to the nonlinearity imposed due to coupling with the connecting rod. Simulation results for the Universal joint system are presented in Fig. 8. A constant torque is app

30、lied to the driving shaft about its axis. The driven shaft makes an angle of 5° with the axis of the driving shaft. The First row shows the response of the driving shaft which is the first link. The component of angular momentum of the driving shaft about its axis increases linearly, which is a

31、s expected. The first two figures of the second row show the change in orientation of the cross, which is link 2. Angular motion about all three axes is clearly visible. The driven shaft follows the motion of the driver shaft as is clear from the third row in Fig. 8.3 ConclusionsThe Bond Graph appro

32、ach is used to model dynamics of two commonly used mechanisms, (1) the Crankshaft Connecting rod Piston Cylinder system, and (2) the Universal Joint system. Pictorial representation of the dynamics of translation and rotation for each link of the mechanism in the inertial frame, representation and h

33、andling of constraints at joints, depiction of cause and effect relationships, coding for simulation directly from the Bond Graph without deriving system equations, have been explained in this work. MATLAB based simulations have been presented and interpreted for both the systems. 曲轴连杆活塞机构及使用键合图法的万向

34、联轴器的动力学仿真建模摘要本文论述了与常用的两种机制的动力学仿真模型，（1）曲轴连杆活塞缸系统，及（2）万向接头系统，使用的键合图方法。这种替代方法的系统动力学仿真，采用键合图，提供了丰富的功能集，包括，对惯性系的机构的各个环节的平移和旋转的动态图形表示，表示和约束节点处理，描述的因果关系，在不同的位置获取动态反应的机理力和力矩，算法的系统方程的推导在第一阶状态空间或因果形式编码进行了仿真，直接从键合图没有导出系统方程，等等。关键词：键合图，建模，仿真，机制。1 建模 常用的两种机制的动态，（1）曲轴连杆活塞缸系统，及（2）万向接头系统，进行了建模和模拟使用的键合图方法。这个系统的动力学方程的

35、替代方法，采用键合图，提供了丰富的功能集 1，2 。这些措施包括，对惯性系的机构的各个环节的平移和旋转的动态图形表示，因果关系，描述表示和约束缝隙处理，在不同的位置获取机制动态反应力和力矩，系统方程的推导在第一阶段状态对空间或原因形式及影响编码进行了仿真，没有直接从键合图导出系统方程。通常机制的链接被建模为刚性体。 在这项工作中，我们开发和应用一个多元图模型的每一个环节都要翻译和刚体的转动。环节进行耦合基于约束3-5自然关节。平移和旋转接头的开发和集成的动态连接。在建模的时候连接接头是一个问题。这能纠正使用附加的刚度和阻尼元件。它使模型更逼真，使合规和耗散在关节的影响，定义在公差范围内。多元图

36、模型的曲轴连杆活塞缸系统，和万向接头系统 6 ，采用键合图方法。每一刚性连接的机制参考框架固定在采用Denavit-Hartenberg公约 7 。翻译的影响主要集中在质量中心的每个刚性连接。旋转效应是惯性框架本身考虑，通过考虑每个环节对各自质心惯性张量，并在惯性坐标系的表达。然后使 多元图的编码在MATLAB中，仿真，进行直接从键合图。一种曲轴机构示意图如图所示，其多元图模型如图2所示。一种万向接头系统示意图如图3所示，其多元图模型如图4所示。从这些机制的动力学仿真得到的结果。1.1曲轴-连杆-活塞缸机构图1显示了“曲轴连杆活塞缸系统示意。” 单个组件被视为刚性连接，连接的接头。第一个移动连

37、接曲柄，第二连杆是连杆、第三连杆是活塞。一架固定在每一个环节。因此，框架1固定链接1，框架2和框架3上连接2，连接3。一个固定的惯性坐标系0，其起源与1帧被选择。然而，它既不旋转也没有翻译。C1，C2和C3是各环节质量中心。该框架固定在各自的链接采用Denavit-Hartenberg公约 4 。 图1的系统动力学是在图2所示的多元图模型。该模型描述了旋转以及在系统中的每个环节的翻译。键合图的左边显示的转动部分和右侧部分显示平移部分。我们限制任何运动的惯性帧O点起源之间的链路上的流量是1，O1 SF应用源为零。同样，我们限制在任何点的相对运动，由A1和A2链接1链接2，通过流量SF应用源为零。活塞是链接3，是约束沿X0方向。这些组件沿Y0和Z0方向翻译是受