教程adams壓縮包群文件msc appendix a

1、APPENDIX A EXAMPLE ANALYSESExample AnalysesThis appendix provides a basic outline of how you can use Adams/Car to analyze your vehicle.Whats in this appendix:Types of AnalysesGather Data for the ModelPackaging Analysis on SuspensionKinematic Analysis on Suspension pliance AnalysisStatic-Loading Dura

2、bility AnalysisDynamic-Loading Durability AnalysisFront Suspension AnalysesFull-Vehicle Design and AnalysisExample AnalysesTypes of AnalysesThe following is a list of analyses that you can perform Adams/Car:Packaging analysis on suspension Kinematic analysis on suspension pliance analysis on suspens

3、ionStatic-loading durability analysis on suspensionDynamic-loading durability analysis on suspensionFull-vehicle design and analysisIn the following pages, a guide is given to perform these analyses. This guide only lists a subset of the analyses available in Adams/Car. Moreover, some additional mod

4、ules may be necessary for the analyses listed (for example, Adams/Durability).For information on a particular analysis, see the Adams/Car online help.Gather Data for the ModelCollect the data necessary to generate an Adams model of the proposed suspension concept. After youve collected the data from

5、 various sources (CAD data for geometry, bushing data from internal testing facilities or from bushing supplier, shock data, and so on), you can create an Adams/Car model.Packaging Analysis on SuspensionOnce youve created the Adams model, you put the virtual suspension on a virtual test fixture (sta

6、ndard part of Adams/Car) and run through a series of events to examine packaging and interference issues. The goal of this analysis is to show that parts do not collide during jounce and roll travel.Also, if body geometry is available, be able to demonstrate that tire and wheel well clearances confo

7、rm to corporate standards. The goal of this phase of the analysis is to give a cursory check of the part collisions within the Adams/Car environment.Further investigations are possible by bringing the Adams results for the wheel envelope during maximum jounce/rebound/roll travel into your CAD packag

8、e. You can use the solid geometry of the wheel envelope in your CAD package to easily find clearance issues, and to better visualize the total wheel envelope needed by your suspension concept.Kinematic Analysis on SuspensionAfter youve analyzed the suspension packaging issues, put the virtual suspen

9、sion on a virtual test fixture and run through a series of events to understand the kinematic properties of the suspension. Two analyses help you understand the suspension kinematics: parallel wheel travel (wheels moving vertically in phase) and roll travel (wheel moving vertically out of phase).The

10、 parallel wheel travel analysis (also called the ride-travel event) examines the following suspension metrics:Toe (also called bump steer)CasterCamberLongitudinal recessionLateral recessionWheel rate (vertical force versus amount of suspension vertical deflection)Kinematic Analysis on SuspensionThe

11、roll-travel analysis examines the following suspension metrics:Roll steer (degrees of toe per degree of suspension roll)Roll stiffnessThe goal of the kinematic analysis is to tune the geometry of the suspension to attain satisfactory kinematic behavior. If kinematic issues arise, design mendations c

12、an then be made to the location of suspension joints and bushings, the lengths of the control arms, and other geometric properties that affect the kinematics of the suspension.Also, suspension spring properties can be examined to be sure that the overall vehicle requirements will be met for suspensi

13、on springs during ride and roll. Use of additional suspension components such as an anti-roll bar can be examined, including mendations about the sizing for the anti-roll bar. pliance AnalysisAfter you analyze the suspension geometry and the design shows good kinematic behavior, you can examine susp

14、ension compliance. The virtual suspension model will be placed on the suspension test rig and run through the compliance analysis (for example, static loading). The following metrics are generated with this analysis:Lateral force versus toe (for both parallel and opposing lateral force)Lateral force

15、 versus camber (for both parallel and opposing lateral force)Lateral force versus lateral displacement (for both parallel and opposing lateral force)Longitudinal force versus toe (braking and acceleration forces)Longitudinal force versus longitudinal displacement (braking and acceleration forces)Ali

16、gning torque versus toe (parallel and opposing torques) pliance AnalysisThe goal of the suspension compliance analysis is to tune the suspension bushings such that adequate suspension compliance is attained. Note that real joints are not infinitely stiff, and they do factor in to the suspension perf

17、ormance. Thus, it may be a good idea to replace idealized joints in your model with bushing representations.Static-Loading Durability AnalysisThe next step in analyzing the suspension is to apply static loadcases to the wheels in Adams/Car and examine the resulting loads of the suspension elements (

18、suspension bushings, suspension springs, and so on). This contributes to a better understanding of the durability of the suspension.Typically, a set of requirements for static loads are used which take the form of a worst case loading condition that a suspension must withstand. These loading conditi

19、ons (or loadcases) take the form of number of gs of loading. For example, a suspension requirement might be that it must withstand 3 gs of vertical load, 2 gs of longitudinal load, and 1 g of lateral load. Such a loading condition is often referred to as a 321 g loadcase.The use of gs describes the

20、total vehicle weight, divided by the front to rear load distribution. In this way, a loadcase requirement in gs of load can be used across different vehicles of various sizes and weights.Static-Loading Durability AnalysisThe goal of the loadcase analysis is to give the design and FEA analyst a repor

21、t which shows the worst case loading on each of the suspension components (control arm, bushings, spring, and so on). This data can then be fed into a FEA model of the component (bushing, control arm, spring, and so on) to show that the component will withstand a given amount of static loading. A st

22、ructured report will be generated through the use of the loadcase postprocessor which will show the amount of loading on the suspension elements, and using this report the loading data can be imported into the FEA software (NASTRAN, ANSYS, ABAQUS, and so on).It is rare that the design engineer can h

23、ave access to this level of data early in the program, so the static loadcase analysis provides the first insight to real-world loading conditions for the parts. This method is coarse and does not provide the final answer to the durability requirements of the suspension components, but early in the

24、design and analysis, this information is extremely valuable.Dynamic-Loading Durability AnalysisAfter the static durability analysis is completed, a more intensive investigation into the rubber mounts begins. In this phase, a road profile will be assumed for the suspension (for example, a pothole, or

25、 random white noise road input) and utilized on a virtual four-post shaker event within Adams/Car. Adams dynamic loading histories of the mounts will then be imported into FEA software for final structural analysis.Front Suspension AnalysesBesides the analyses already listed, specific to the front s

26、uspension, steering system metrics will also be examined to understand the overall steering ratio, steering linearity, Ackerman, and steering column universal joint phasing (ensure that the steering feel is not lumpy).Full-Vehicle Design and AnalysisOnce the rear suspension, front suspension, and st

27、eering system subsystems have been modeled in Adams/Car, the next stage of the Functional Digital Car process is to analyze the full vehicle behavior. Because the various suspension subsystem models have been developed in the earlier stages of the plan, it will be a simple matter to assemble these subsystems into a full vehicle Adams/Car model.This Adams/Car model will