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Short-Long Arm SuspensionGUI Familiarity Level Required: LowerEstimated Time Required: 40 minutes

MSC.ADAMS 2005 r2

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Topics CoveredTopics Covered

In this tutorial you will learn how to:

You will need to download SLA_Suspension_start.cmd to begin this tutorial

If you have any difficulties, import the “SLA_Suspension_shortcut_1.cmd” file and proceed from pg 11

If you have any difficulties, import the “SLA_Suspension_shortcut_2.cmd” file and proceed from pg 13

If you have any difficulties, import the “SLA_Suspension_shortcut_3.cmd” file and proceed from pg 15

If you have any difficulties, import the “SLA_Suspension_shortcut_4.cmd” file and proceed from pg 17

If you have any difficulties, import the “SLA_Suspension_complete.cmd” file and proceed from pg 24

1. Create three-component force vector

2. Modify force vector

3. Create simple harmonic function

4. Create force vector

5. Create preloaded translational spring damper

6. Deactivate joint

7. Create bushings

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Short-Long Arm Suspension ProblemShort-Long Arm Suspension Problem

Add bushings, translational spring damper and forces to a short-long arm suspension mechanism.

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What You Should AccomplishWhat You Should Accomplish

When you complete this tutorial you will have a working ADAMS model of a short-long arm suspension system.

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Importing ModelImporting Model

a. Select Import a file radio button

b. Click OK

File Import window will open

c. Right-click File To Read text field, select Browse

d. Locate saved file SLA_Suspension_start.cmd

e. Click Open

f. Click OK

a

c

d

ef

b

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Create Force Vector (Three-Component Force)Create Force Vector (Three-Component Force)

a. Select Force Vector (Three-Component Force) from Forces tool stack

b. Turn on damping coefficient (K) checkbox and enter (0.525Ne/m/sec )

c. Turn on stiffness coefficient (C) check box and enter (375Ne/mm)

d. Click spindle right click on center of tire and select patch right click on center of tire and select patch.MAR130

a

b

d

c

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Modify MarkerModify Marker

a. Right-click force, select Marker: MARKER_151 Modify

b. Enter 0.0, 0.0, 0.0 in Orientation text field

c. Click OK

c

ba

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RenameRename

a. Right-click on force, select Force_Vector: VFORCE_1 Rename

b. Enter .sla_complete.tire_compliance in New Name text field

c. Click OK

b

a

c

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Modify Force VectorModify Force Vector

a. Right Click on force, select Force_Vector: tire_compliance Modify

b. Enter 0 in X Force and Y Force text field

c. Click button next to Z Force text field

a

b

c

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Create Impact FunctionCreate Impact Function

a. Enter: impact(DZ(vert_ref,contact_surface,ground.contact_patch),

VZ(vert_ref,contact_surface,ground.contact_patch),290,375.0,1.01,0.525,3)

into Define a runtime function text field

b. Click OK

a

b

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Add Translational Joint MotionAdd Translational Joint Motion

a. Select Translational Joint Motion from Motion Driver tool stack

b. Click patch_to_ground (translational joint)

c. Right-click on motion, select Motion: road_motion Modify

d. Click button next to Function (time) text field

a

b

c d

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Create a Simple Harmonic Function Create a Simple Harmonic Function

a. Select Math Function from pull

down menu

b. Select Simple Harmonic

c. Click Assist button

d. Enter time in X text field

e. Enter 0 in Shift text field

f. Enter 3500d in Frequency text field

g. Enter 90.0d in Phase Shift text field

h. Enter 50 in Amplitude and Average

value of Displacement text field

i. Click OK

j. Make sure the Define a runtime

function text field reads:

SHF(time, 0.0, 50.0, 3500.0d, 90.0d, 50.0)

k. Click OK

a

b

c

jd

ef

g

h

i

k

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Create Force (Single Component)Create Force (Single Component)

a. Select force (Single Component) from Force tool stack

b. Select Two Bodies from Run-time Direction pull down menu

c. Click ground lca ground.POINT_7 lca.POINT_8

a

b c

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Modify ForceModify Force

a. Rename force to .sla_complete.bump_stop

b. Modify Force, click button next to Function text field

c. Enter

impact(DM(point_8, point_7),VR(point_8, point_7)

,51,5779,1.01,5.8,0.5)

In Define a runtime function text field

d. Click OK

e. Click OK

a

d

c

b

e

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Create Translational Spring DamperCreate Translational Spring Damper

a. Select Translational Spring Damper from Force text field

b. Click lca.POINT_6 ground_POINT_5

a

b

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Modify Spring DamperModify Spring Damper

a. Right-click spring, select Spring: SPRING_1 Modify

b. Enter (60(newton/mm)) in Stiffness Coefficient text field

c. Enter (0.46(nextown-sec/mm)) in Damping Coefficient

d. Enter 0.0 Preload text field

e. Enter (404mm) in Length at Preload text field

f. Click OK

a

b

c

d

e

f

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Deactivate JointDeactivate Joint

a. Right-click revolute joint, select Joint: lca_to_ground (De)activate

b. Turn off Object Active and Object’s Dependents Active checkbox

c. Click OK

d. Repeat for Joint: uca_to_ground

a

b

c

d

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Create BushingCreate Bushing

a. Select Bushings from forces tool stack

b. Click uca ground ground.POINT_1

a

b

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Modify BushingModify Bushing

a. Right click bushing, select Bushing: BUSHING_1 Modify

b. Enter 2627.0, 2627.0, 876.0 in Stiffness text field

c. Enter 1.75, 1.75,0. 875 in Damping text field

d. Enter 0.0, 0.0, 0.0 in Preload, Stiffness, Damping and Preload text field

e. Click OK

a

b

c

d

e

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Create BushingsCreate Bushings

Create 3 more Bushings

Bushing 1 & 2

Stiffness: 2627.0, 2627.0, 876.0

Damping: 1.75, 1.75, 0.875

Bushing 3 & 4

Stiffness: 3503.0, 3503.0, 1401.0

Damping: 2.62, 2.62, 1.4

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3

4

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ModelModel

This is what your screen should look like when your model is complete

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Create Point-to-Point MeasureCreate Point-to-Point Measure

a. Click Build menu Measure Point-to-Point New

b. Right-click in To Point text field, select Marker Browse

c. Select sla_complete spindle wheel center

d. Click OK

a

b

c

d

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Create Point-to-Point MeasureCreate Point-to-Point Measure

a. Enter wheel_height in Measure Name text field

b. Select spindle.wheel_center in To Point text field

c. Select ground.wheel_center in From Point text field

d. Verify that Translational displacement is selected from Characteristic pull down menu

e. Select Z radio button from Component menu

f. Click OK

f

e

d

cb

a

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Verify Your ModelVerify Your Model

Run simulation (Duration = 10, Step Size = 0.1)

Verify your model, should have 11 degrees of freedom and no redundant constraints

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Topics CoveredTopics Covered

In this tutorial you will learn how to:

1. Create three-component force vector

2. Modify force vector

3. Create simple harmonic function

4. Create force vector

5. Create preloaded translational spring damper

6. Deactivate joint

7. Create bushings

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Best PracticesBest Practices

• Make sure all forces, joints and bushings are correctly oriented

• Make sure the functions are correctly set

• Verify the positions of joints, forces, bushings

• Check values of bushings, spring and force