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Spring-Mass Damper

GUI Familiarity Level Required: Higher

Estimated Time Required: 15 minutes

MSC.ADAMS 2005 r2

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Topics Covered

If you have any difficulties, import the “spring-mass.damper.shortcut.cmd” file and proceed from pg 6

If you have any difficulties, import the“spring-mass.damper.complete.cmd” file to proceed from pg 8

In this tutorial you will learn how to:

1. Add a spring

2. Add a stiffness/damping to a spring

3. Measure Translational Displacement

4. Measure Translational Velocity

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Spring Mass Damper Problem

The 10-kg cylinder is released from rest with x = 1 m, where the spring is unstretched. Determine (a) the maximum velocity v of the cylinder

and the corresponding value of x and (b) the maximum value of x during the motion. The stiffness of the spring is 450 N/m.

Problem 3/142 from J. L. Meriam and L. G. Kraige, Engineering Mechanics: Volume 2, Dynamics 3rd edition. John Wiley & Sons, Inc.

Copyright © 1992, by John Wiley & Sons, Inc. This material is used by permission of John Wiley & Sons, Inc.

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What You Should Accomplish

If you are successful, you should end up with a working ADAMS model that illustrates the motion of a spring that is being stretched

due to mass and gravity

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Setting up model

a. Start ADAMS.

b. Create a new model. (Units = mks, Gravity = -y earth)

c. Enlarge working grid area to accommodate model. (height approx. 1.5 m)

d. Create cylinder (mass = 10 kg). Starting at (0,-1,0) to (0,-3,0).

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Creating a Spring

a. Select the Translational Spring Damper from the Connector tool stack

b. Turn on Stiffness Coefficient (k), enter 450 N/m

c. Turn on Damping Coefficient (c), enter 0 N-s/m

d. Click on (0,0,0)

e. Click on (0,-1,0)

Verify your model

a

bc

d

e

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

Model

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Testing the Model

Measure Translational Displacement and Translational Velocity of the marker at (0,-1,0), End time = .234, Step =50

Measure Translational Displacement of the marker at (0,-1,0), End time = 0.468, Step = 50

Translational Displacement Translational velocity

Translational Displacement

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Theoretical Solution ADAMS solution

Results

(a1) Maximum velocity = 1.462m/s;

(a2) Displacement = 1.218m at t=0.234s

(b) Maximum displacement = 1.436m at t=0.468s

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Topics Covered

In this tutorial you will learn how to:

1. Add a spring

2. Add a stiffness/damping to a spring

3. Measure Translational Displacement

4. Measure Translational Velocity

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Best Practices

• Make sure correct units are set to mks.

• Make sure gravity is on and in the -y direction and set to 9.806.

• Check mass and distance of the block to make sure they are correct.

• Make sure the damping coefficient = 0.

• Make sure the measures are set correctly.

• Make sure the plot is displaying the correct set of results.

• Make sure there are enough output steps to observe the velocity and maximum displacement.

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Further Analysis (Optional)

How does the addition of damping coefficient effect velocity and displacement?

If you remove the Stiffness on the spring is there any change?

How much does the spring deform after 5 seconds?

How much force is applied by the spring?