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Incline Plane

Estimated time required: 15 min

GUI familiarity level required: Higher

MSC.ADAMS 2005 r2

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Topics CoveredTopics Covered

If you have any difficulties, import the “incline_shortcut.cmd” file and proceed from pg 7

If you have any difficulties, import the “incline_complete_15deg.cmd” file and proceed from pg 8

If you have any difficulties, import the “incline_complete_20deg.cmd” file and proceed from pg 10

In this tutorial, you will learn how to:

1. Add friction to a translational joint

2. Change friction input forces

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Incline Plane ProblemIncline Plane Problem

Problem 3/2 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.

The 100-lb crate is carefully placed with zero velocity on the incline. Describe what happens if:(a) theta = 15 degrees and (b) theta = 20 degrees.

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If you are successful, you should end up with a ADAMS model that illustrates a box with friction traveling down

an incline.

What You Should AccomplishWhat You Should Accomplish

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Creating the ModelCreating the Model

a. Start ADAMS.

b. Create a new model. (Model Name = incline, Units = ips, Gravity = - Y earth)

c. Resize the working grid, Size = X – 75i, Y – 50i, Spacing X – 1i, Y – 1i

d. Create ground plane. (box on ground, length = 46 in, height = 2 in, depth = 8 in)

e. Create crate part. (box, length = 10 in, height = 4 in, depth = 8 in, mass = 100 lb), rename .incline.BLOCK

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Create a Translational Joint with FrictionCreate a Translational Joint with Friction

a. Create a translational joint between crate and ground plane

b. Right click on the joint, select Joint: JOINT_1 Modify

c. Click Joint Friction button

d. Enter Mu Static = 0.30, Mu Dynamic = 0.25

e. Turn on Reaction Force under Input Force to Friction (all others should be off)

f. Click OK

g. Click OK

a

b

c

d

f

e

g

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Test Model at 15Test Model at 15°°

a. Rotate model to angle theta = 15 degrees. (select both the plane and the crate, and use the rotate tool)

b. Run simulation and record results. (end time = 1, time steps = 50)

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Test Model at 20°Test Model at 20°

a. Rotate to new angle theta = 20 degrees. (20 degrees from ground)

b. Measure the mag (magnitude) of the CM acceleration

c. Run another simulation.

d. Transfer the small graph to a full plot in the ADAMS plotting screen. (right mouse button inside small plotting window)

e. Use the Display Plot Statistics tool to follow the plot curve. Find the value for Y when X = 1.0

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

ModelModel

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Theoretical Solution ADAMS solution

ResultsResults

Textbook solution:At angle theta = 15 degrees, there is no motionAt angle theta = 20 degrees, the block accelerates down the plane.             

41.35 in/sec^2 =3.45 ft/sec^2

At angle theta = 15 degrees, there is no motion

At angle theta = 20 degrees, the block accelerates down the plane.

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In this tutorial you learned how to:

Topics CoveredTopics Covered

1. Add friction to a translational joint

2. Change friction input forces

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Best PracticesBest Practices

• Make sure correct units are set to ips.

• For ease of part creation, the working grid can be set to inches.

• Make sure gravity is on and in the -y direction and set to -386.089.

• Check weight of crate to make sure it is correct. It may need to be set manually.

• Check dimensions of parts. 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 effect at each angle setting