Adams Lecture1

8/8/2019 Adams Lecture1

1/53

MSC ADAMSTUTORIAL #1: SIMPLE MECHANISM

MTR 501

INTRODUCTION TO MECHATRONICS


2/53

AB is a uniform bar with a mass of 2 kg and a length of 450mm. BarAB swings

in a vertical plane about the pivot atA.

The angular velocity (theta dot) = 3rad/s when theta = 30 degrees. Compute the force supported by the pin atA at

that instant.


3/53

1.1. Starting ADAMS.

On a Windows Machine, click on the Start Programs ADAMS 12.0

AView ADAMS View

The Welcome to ADAMS dialog box appears as shown in Figure 1.

Under the heading "How would you like to proceed", select Create a new

model.

Verify the Gravity text field is set to Earth Normal (-Global Y).

Verify that the Units text field is set to MMKS - mm,kg,N,s,deg.

Select OK.

One last thing before we start, we are going to changed the coordinate

settings; this is done by going to ADAMS/View Settings menu and select

Working Grid. The Working Grid Settings dialog box appears. One of the

options we have is to change the spacing, change it to 25mm, click OK after it

is finished. This can allow you to change other grid settings, such as

dimensions and design. You can also switch to polar coordinates in this

window, which is useful for measuring angles.


4/53


5/53


6/53


7/53


8/53

Making the bar.

1.Click on the parts palette in the Toolbox with the right mouse button.

The button stack for parts appears.

1.Select the Rigid Body: Link tool. with the left mouse button.2.In the link container at the bottom of the Toolbox, activate the Length toggle

switch and enter 450mm in the text field below.3.Activate the Width toggle switch and enter 20mm in the text field.4.Activate the Depth toggle switch and enter 27.5mm in the text field.5.Click once with the left mouse button on the point (-225,0,0) to select the

starting point (to see the coordinate press F4) and click once with the left mouse

button anywhere right of the start point along the global x-axis to select the

direction. ADAMS will create and display the bar. The display should appear similarto Figure 2 below.


9/53


10/53


11/53


12/53


13/53


14/53


15/53


16/53


17/53

Setting the position of the bar.1.To set the angle of the bar at 30 degrees, click on the Positionicon in the Toolbox.

2.Enter 30 in the Angle entry and select the bar so it is highlighted.3.Click on the clockwise arrow once.

The bar is now at a 30 degree angle from horizontal.


18/53


19/53


20/53


21/53


22/53


23/53


24/53


25/53


26/53

Setting initial motion.

All of the parts have now been created and the constraints added.

The next step is to add an initial motion to the revolute joint thatspecifies a starting rotation rate of three radians per second.

Click and hold the bar with the right mouse button and follow the pull

right menu forPart:PART_2 and select Modify.

In the Category: entry, use the pull down arrow to select Velocity

Initial Conditions.

Under the heading Angular velocity about, select Part CM.

Corrections by Li Wang (Please think about whats wrong with the old

version):

3. Under the heading Angular velocity about, select Marker. In the

box below, enter MARKER_4 or double click the box and find

MARKER_4 under the ground directory.

Below that, click on the Z axis selection box and enter3.0r, for 3.0

radians per second, in the text field that appears next to it.

Click on Apply and close the window.

Click on Ok in the Modify window.


27/53


28/53


29/53


30/53


31/53


32/53


33/53


34/53

Verify the model.

The model verification step is one way to find errors in the modeldefinition. ADAMS checks for error conditions such as misaligned joints,

unconstrained parts, or massless parts in dynamic systems, and alerts you

to other possible problems in the model.

1.In the lower right corner of the modeling window, click on the

Information icon with the right mouse button.

The information palette appears.

1.Click on the Verification icon.

The Info Window appears.1.After seeing that the model has verified successfully, click on the Close

button in the upper right corner to close the Information Window.


35/53


36/53


37/53


38/53

Setting measure for the force supported by the pivot at point A.

Click on the revolute joint at the upper left end of the bar with the right mouse

button and follow the pull-right menu forJoint:JOINT_1 and select Measure.

The Joint Measure dialog box opens.

Select Force for the Characteristic entry and mag (magnitude) for the

Component entry.

Click OK.

A graph window named JOINT_1_MEA_1 appears. This is where the reaction

force will be displayed during the simulation and animation.


39/53


40/53


41/53


42/53


43/53


44/53


45/53


46/53


47/53


48/53


49/53


50/53


51/53


52/53


53/53

Solution:The force supported by pivot A is 14.5 N.

Adams Lecture1

Documents

Transcript of Adams Lecture1