Incline Plane MSC.ADAMS 2005 r2 Estimated time required: 15 min GUI familiarity level required: Higher MSC.ADAMS 2005 r2

Topics Covered In this tutorial, you will learn how to: Add friction to a translational joint Change friction input forces 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

Incline Plane Problem 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. 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.

What You Should Accomplish If you are successful, you should end up with a ADAMS model that illustrates a box with friction traveling down an incline.

Creating the Model Start ADAMS. Create a new model. (Model Name = incline, Units = ips, Gravity = - Y earth) Resize the working grid, Size = X – 75i, Y – 50i, Spacing X – 1i, Y – 1i Create ground plane. (box on ground, length = 46 in, height = 2 in, depth = 8 in) Create crate part. (box, length = 10 in, height = 4 in, depth = 8 in, mass = 100 lb), rename .incline.BLOCK

Create a Translational Joint with Friction Create a translational joint between crate and ground plane Right click on the joint, select Joint: JOINT_1  Modify Click Joint Friction button Enter Mu Static = 0.30, Mu Dynamic = 0.25 Turn on Reaction Force under Input Force to Friction (all others should be off) Click OK a d b e c g f

Test Model at 15° Rotate model to angle theta = 15 degrees. (select both the plane and the crate, and use the rotate tool) Run simulation and record results. (end time = 1, time steps = 50)

Test Model at 20° Rotate to new angle theta = 20 degrees. (20 degrees from ground) Measure the mag (magnitude) of the CM acceleration Run another simulation. Transfer the small graph to a full plot in the ADAMS plotting screen. (right mouse button inside small plotting window) Use the Display Plot Statistics tool to follow the plot curve. Find the value for Y when X = 1.0

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

ADAMS solution Theoretical Solution Results At angle theta = 15 degrees, there is no motion At angle theta = 20 degrees, the block accelerates down the plane. 41.35 in/sec^2 =3.45 ft/sec^2 Textbook solution: At angle theta = 15 degrees, there is no motion At angle theta = 20 degrees, the block accelerates down the plane.              

Topics Covered In this tutorial you learned how to: Add friction to a translational joint Change friction input forces

Best 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