Transcript No Slide Title

Introduction to ADAMS
Course manual for Multibody Dynamics A, wb1310
Martijn Wisse
29th december 1999
revised for V2005.0.0 by Bram Soethoudt
Multibody Dynamics A, wb1310
May 2005
1
Contents
1
Example
3
2
Program Overview
15
3
Layout & View Control
19
4
Parts & Geometry
23
5
Joints & Motion generators
26
6
Markers
30
7
Springs & Force generators
31
8
Simulations & Animations
35
9
Plotting & Measures
41
10 Tips & Useful Tools
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Contents
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2
Creating a new model
• Start ADAMS-View:
Aview  ADAMS-View
Data Analysis & Simulation Software  Adams 12.0 
• Use the startup dialogbox or from the Menu-bar select Build  Model  New…
• Change the Model Name to ‘example_1’
• Click OK, ADAMS is now ready to construct a model
Multibody Dynamics A, wb1310
Example
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Environment Settings
To set gravity and units settings:
• From the Menu-bar select Settings  Gravity…
• In the Gravity Settings window check the Gravity checkbox
• Apply
• From the Menu-bar select Settings  Units…
• Select
Multibody Dynamics A, wb1310
Example
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Creating a new link
• In the Main Toolbox click the icon Rigid Body: Link
• Check options Length, Width and Depth,
• Fill in desired dimensions: ‘(373mm)’, ‘(6mm)’ and ‘(6mm)’
* Hit return after entering the dimensions
* Notice instructions in lower left corner of screen
• Pick location of first end of link
• Pick second location to define orientation of link
Multibody Dynamics A, wb1310
Example
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Creating a new joint
• In the Main Toolbox click the icon Joint: Revolute
• Select construction options:
- 1 Location
- Normal to grid
• Pick the location of the revolute joint on an existing rigid body
Multibody Dynamics A, wb1310
Example
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Naming the model elements
• Right click on the created link
• Select Part: Part_1  Rename
• Change name into ‘.example_1.pendulum’
• Repeat procedure for the created joint
• Rename joint as ‘.example_1.hinge’
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Example
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Naming the view window
• From the Menu-bar select View  View Accessories...
• In the View Accessories window type your id
• Click Enter
• Close View Accessories window
• Your id appears in the upper left corner of the model view
window
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Example
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Rotating model elements
• In the Main Toolbox select the Select-tool
• Left click on the pendulum to select
• In the Main Toolbox select the Center-tool
• Center the view at the hinge
• In the Main Toolbox select the Position-tool
• Rotate the pendulum 30 degrees
Multibody Dynamics A, wb1310
Example
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Saving the model
• From the Menu-bar select File  Export
• In the File Export window right click at File Name
• Select Browse...
• Save model as ‘example_1.cmd’ in the File Selection window
• In the File Export window click OK
• Save your work frequently
Multibody Dynamics A, wb1310
Example
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Loading a model
• From the Menu-bar select File  Import
• In the File Import window right click at File
To Read
• Select Browse...
• Open existing ‘.cmd’ - file
* Note: if the model was already loaded,
a number of errors appears
Multibody Dynamics A, wb1310
Example
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Running a simulation
• In the Main Toolbox select the Simulation-tool
• Change the number of steps into ‘100’
• Left click the Start or continue simulation button
• To simulate again, first press the Reset to input configuration button
* Note: The viewport shows the simulation; to return to the model view,
left click the Select-tool
* Note: The simulated motion is stored, and available for animation or
plotting
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Example
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Plotting simulation results
• In the Main Toolbox select the Plotting-tool
• For the Object to plot choose Constraint  hinge  Ax_Ay_Az_Projection_Angles  Z
• Click Add Curve
• Double-click Page_1 and click on Plot_1
• Add Title and insert your id as Subtitle
• Click OK
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Example
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Simulation results
• Print your graph
• To leave the Plot Window click Return to modeling environment
This is the end of the example
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Example
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The ADAMS interface
The ADAMS interface consists of two main windows:
- the View Window, displaying your current model
- the Main Toolbox
Most common ADAMS functions can be accessed through the Main Toolbox. All functions can also
be found under the the Menu bar in the View Window.
Title
Main Toolbox
Modeling and
simulation tools
Right click to
open individual
tool stacks
Container
Display changes
depending upon
the tool selected
from the tools
above
Menu Bar
Working Grid
Coordinates Window
Triad
Multibody Dynamics A, wb1310
Instruction Bar
Program Overview
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ADAMS Online Help
ADAMS has an extensive online help facility in HTML and PDF format.
Most documentation on model construction is to be found under ADAMS/View.
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Program Overview
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The ADAMS model hierarchy
The model element naming is consistent with the
hierarchy (e.g. model_name.part_name.geometry_name
or model_name.joint_name)
Database
Model
Plot
GUI
Curve
Simulation Output
Do not get
saved in
model
command
file format
(.cmd)
(See next
Page for
explanation)
Analysis
 More...
Model Elements
Measure
Constraint
Force
Part
Results Set
Marker
Construction points
Geometry
Component
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Program Overview
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File Handling in ADAMS
The two most common formats in which models in ADAMS can be saved are:
1
ADAMS/View Database files (.bin)
 Include the entire modeling session including models,
simulation results, plots, etc.
 Are large binary files
2
ADAMS/View Command files (.cmd)
 Includes only the model elements and their
attributes
 Are relatively small, editable text files
The other formats in which data in ADAMS can be
imported and exported are:
 ADAMS/Solver Input files (.adm)
 Geometry files (STEP, IGES, DXF, DWG,
Wavefront, stereolithography)
 Test and Spreadsheet data files
 Simulation results files (.msg, .req, .out, .gra, .res)
Multibody Dynamics A, wb1310
Program Overview
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View settings
View settings from the Main Toolbox:
Background Color
Triad visibility (the global coordinate system displayed in the
lower left corner of the View Window)
View layout
Icon appearance: double click on the Icons button
Setting the View Title:
•
From the Menu-bar choose View  View Accessories
•
Set your id as View Title in the View Accessories window
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Layout & View Control
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Viewpoint controls
The Viewpoint can be controlled from the Main Toolbox. Click the Selecttool and use the following view controls:
Fit
Rotate
Window zoom
Pan
Center
Zoom
And the preset view orientations:
Front
Right
Top
Isometric
Multibody Dynamics A, wb1310
Layout & View Control
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Setting Object Appearances
The appearance of a displayed object can be altered when the object is selected
(highlighted):
• color: From the Menu-bar select Edit  Appearance
change Color by right-clicking the Color-field
render mode: From the Menu-bar select View  Render Mode
toggle render on/off in the Main Toolbox
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Layout & View Control
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The Working Grid
The Working Grid is used:
• as a plane for creating objects
• to draw, move, resize, reshape geometry by snapping to grid
Change Working Grid settings by double-clicking the Grid-button
on the Main Toolbox (first apply the Select-tool)
When creating a new model element, first set the Working Grid with the
correct location and orientation.
Set the location of the Grid origin by:
• global origin, or
• pick location
Set the orientation as one of the principal planes:
• Global XY,
• Global YZ, or
• Global XZ
Multibody Dynamics A, wb1310
Layout & View Control
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Creating Parts & Geometry
Each rigid body in ADAMS is modeled as a part. Each part has one or more
geometries. To create a new part, start with a geometry, e.g. a box or a cylinder.
To create a new geometry:
• In the Main Toolbox right-click on Rigid Body
• Select the appropriate geometry:
Link
Sphere
Box
Torus
Cylinder
• Choose New Part or Add To Part
• Enter required dimensions
• Follow instructions in lower left corner of screen
* When adding a geometry to an existing part, check the position of the
automatically generated ‘Center of Mass’-marker
Multibody Dynamics A, wb1310
Parts & Geometry
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Positioning Objects
Reposition objects
relative to viewing
coordinates
Reposition objects
relative to the
working grid
Translate from an
initial location to
another
Rotate about or align
with grid or features
Rotation:
Multibody Dynamics A, wb1310
Position objects by
aligning faces
Translation:
Parts & Geometry
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Modifying Part Properties
To modify Mass and Inertia properties of a part:
• Right-click on the part to be modified
• ADAMS/View displays the names of all model elements near the cursor
• Select the part to be modified and then select Modify
• In the Modify Rigid Body window enter the user specified mass and inertia values
To modify the name of the part:
• Select the part to be modified and then select Rename
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Parts & Geometry
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Joints
In ADAMS joints are used to connect rigid bodies to each other or to the ground with a
limited number of degrees of freedom.
To create a new joint:
• Both parts to be connected by the joint should already exist
• In the Main Toolbox right-click on Joint
• Choose the appropriate joint:
revolute
translational
• Choose a connection between one part and the ground: 1 location,
or between two parts: 2 Bod - 1 loc
• Choose the orientation of the joint by setting the axis for the degree of freedom:
- normal to the Working Grid
- in a direction indicated with the mouse
• Follow instructions in lower left corner of screen
Multibody Dynamics A, wb1310
Joints & Motion Generators
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Creating a Motion Generator
A degree of freedom in a joint can be replaced by a prescribed motion. A motion can be
defined as displacement, velocity or acceleration as a function of time.
To create a motion generator:
• A joint should already exist
• In the Main Toolbox right-click on Rotational Joint Motion
• Choose the type of motion, equal to the degree of freedom allowed by the joint:
rotational, or
translational
• Enter the desired constant velocity
* When applying a rotational velocity, enter the letter d to ensure that ADAMS uses as
units degrees/second
• Follow instructions in lower left corner of screen
• If an other motion function than a constant speed is desired, modify the motion
generator afterwards
Multibody Dynamics A, wb1310
Joints & Motion Generators
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Motion Generators with non-constant velocity
The prescribed motion of a motion generator can be a complex function of time. First,
a motion generator with constant velocity must have been created.
To modify the motion function:
• Select the motion generator and then select Modify
• In the Impose Joint Motion window select the type of motion generator
• Right-click in the ‘F(time)=’-field
• Select Function Builder…
• Define a runtime function, using ‘time’ as independent variable, or
• Enter a more complex predefined function (next page)
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Joints & Motion Generators
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The Function Builder
To enter a complex mathematical function of time for the motion generator:
• In the Function Builder window select the desired math function
• Use the Assist… dialog box
• Use the Verify button before
the Function Builder
closing
* Note: The Function Builder cannot read lines over 80 characters long
* Note: If the function is new to you, see the description in the Help
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Joints & Motion Generators
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Markers
In ADAMS, important geometrical points on a rigid body are represented by Markers. A marker is a
massless entity, only possessing a location and an orientation. When a new rigid body or joint is created,
ADAMS automatically creates the necessary markers (e.g. the ‘Center of Mass’-marker).
When a spring or other force must be attached at a previously undefined location on a part, first a new
marker must be created.
To create a new marker:
• In the Main Toolbox right-click on Rigid Body
• Select Marker
• Choose Add to Ground or Add to Part
• For the orientation of the marker, choose one of the principal planes:
- Global XY
- Global YZ
- Global XZ
• Follow instructions in lower left corner of screen
Multibody Dynamics A, wb1310
Markers
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Spring/Damper
To create a spring/damper combination:
• Two markers on different parts should already exist for spring attachment
• In the Main Toolbox choose Connector: Translational Spring-Damper
• Check applicable properties and enter user-specified values
• Follow instructions in lower left corner of screen
To change properties and graphic representation:
• Select spring to be modified and then select Modify
* Note: in order to see the diameter ratio option, load the <Sayfield> menu from the menu bar
Multibody Dynamics A, wb1310
Springs & Force Generators
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Applied Force: Torque
To create an applied torque on a rigid body:
• A marker should already exist as point of application for the torque
• In the Main Toolbox right click on Connector
• Select Applied Force:Torque (single component)
• Choose a Runtime Direction and Construction (initial direction)
• Choose Characteristic:
- a simple force, or
- a to be defined complex custom function
• Follow instructions in lower left corner of screen
To alter the force function:
• Right-click on the torque and select Modify
• In the Modify a Torque window right click in the ‘F(time,…)’-field
• Use the Function Builder
* Note: In contrast with a motion generator, an applied torque can be a function of positions of objects
Multibody Dynamics A, wb1310
Springs & Force Generators
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Special Force: Tire
A tire is represented in ADAMS as a special type of force. This special force automagically generates
a part for the wheel.
To create a new tire:
• In the Main Toolbox right click on Connector and select Tire
• In the Create Wheel and Tire window enter the following data:
• Enter Name
• Enter user specified Mass and Inertia properties
• Enter the required Tire Property File
• Enter the required Road name (create if it does not exist)
• Enter Location of the cm and Orientation of the wheel axis: default
(0,0,0) is the wheel axis along the z-axis
Multibody Dynamics A, wb1310
Springs & Force Generators
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Creating a Road
A tire in ADAMS needs a road. Multiple tires can use one road.
To create a new road:
• In the Create Wheel and Tire window right click on
Road and select Create
• In the Create Road window enter the following data:
• Name
• Part that the road is attached to (usually ground)
• the required road Property File
• adjust the Euler Angles to (0,-90,0) for the plane
y=0, contact if y<0
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Springs & Force Generators
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Debugging
Before running a simulation, you should check your model; are all parts
connected as intended?
To check the number of Degrees of Freedom:
• use the Verify tool in the lower right corner of the screen
• the Information window displays the number of degrees of freedom, the
number of moving parts and the number of joints
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Simulation & Animation
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Running a simulation
To run a simulation:
• In the Main Toolbox select the Simulation-tool
• Select Default analysis
• Enter the desired End Time or Duration
• Enter the desired integration Step Size or Number of Steps
• Select the Debug option, ADAMS shows the Maximum Equation Error window
• Use the Start, Stop and Rewind buttons
• To access advanced simulation settings, apply … (More)
See (next page)
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Simulation & Animation
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Simulation Settings
Advanced Simulation Settings:
• In the Main Toolbox select the Simulation-tool, then select …(More)
• To find static equilibrium, apply
• To perform a linear modes analysis, first find static equilibrium, then apply,
In the Linear Modes Controls window use
,
and
to display
and animate the eigenfrequencies and eigenmodes
• To change the integration accuracy, apply Simulation Settings…
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Simulation & Animation
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Types of Virtual Simulations in ADAMS
Assembly Operation
Assemble
Linear
Non-Linear
Eigensolution or State Matrices
Motion Study
Linear
Equilibrium Calculation(s)
Static*
Default*
Non-Linear
DOF=0
DOF>0
Dynamic*
Kinematic*
*Automatically performs an assembly operation
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Simulation & Animation
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Basic Animation Control
After Performing a simulation, the Animation Container on the Main
Toolbox can be used to control the animation
Play-forward
Stop Animation
Step Backward
Play-reverse
Step Forward
Reset to Frame 1
Modify Animation View
Frame Slider
Drag until the required frame is
reached
Loop Function
Select to replay animation
indefinitely
Multibody Dynamics A, wb1310
Fixed Base: camera is fixed on the
ground
Base Part: camera is fixed on the
CM of the part
Base Point: camera is fixed on the
selected CSM
Advanced Animation features
Simulation & Animation
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Animation and Rendering
ADAMS has a built-in movie generator, which produces computer animations in .AVI-format.
To make an .AVI-movie:
• After running a simulation, select View  Load Animation from the Plotting Main Menu
• Select desired view with the View Control toolbars or right click in main window
• If desired adjust settings for Animation, View, Camera, Record, Overlay, Contours
• Press record
and press play
to start the recording
• Movie is saved in working directory (default is L:\)
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Simulation & Animation
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Overview of the Plot
Plotting main menu
Plot formatting
Multibody Dynamics A, wb1310
Plotting toolbar
Manage pages of plots
Return to modeling
Plot location
Plotting & Measures
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Overview of the Plot Builder
Displays list of current
simulations
Detailed List of Output
Parameter to plot against
Types of results to be displayed:
Objects, Measures, Requests and Results
Multibody Dynamics A, wb1310
Manages curves of plots
Plotting & Measures
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Useful Plot functions
Useful functions in the Plot Window:
Display Plot Statistics
Zoom
Return to modeling environment
Useful functions in the Plot Builder:
Surf; automatically clears and updates plots as items are selected
Data filter
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Plotting & Measures
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Creating Measures in ADAMS
To create measures…
1 Use the Main Menu
Build| Measure
can be used for all measures
2 Use the Measure Tool Stack on
the Main Toolbox
can be used for point-topoint and included angle
measures
3 Use the right mouse button and
select Measure from the pop-up
menu
can be used for object and
point measures
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Plotting & Measures
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Tips & Tricks
Some general tips & tricks:
• Use the Escape key to abort a command.
• Press ‘Enter’ after input to make sure that the new value is set.
• Edit  Copy generates a copy at the same location as the original.
Right-click on the model to select the copied element.
• Right click on any field for suggestions or options.
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Tips & Useful Tools
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Navigating through a Modeling Database
Use the Database Navigator to view and select
objects in a modeling database
“+” indicates
To open the Database navigator…
existence of
hidden children
 Use the menu bar
Tools| Database Navigator
 Execute an editing command
when no object is selected
“-” indicates all
children objects
are displayed

The Database Navigator only displays those types
of objects that are appropriate for the command
you are executing
Multibody Dynamics A, wb1310
Tips & Useful Tools
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Using the Command Navigator
Use the command Navigator to enter ADAMS/View commands without knowing the
entire command syntax
The Command Navigator…

displays a list of all the
ADAMS/View command
keywords
“+” indicates
existence of hidden
command levels

corresponds to the matching
menus available in previous
versions of ADAMS/View
“-” indicates that the
next command level
is currently
displayed

lets users perform advanced
commands not immediately
accessible

helps users learn the command
syntax when customizing
ADAMS/View
Multibody Dynamics A, wb1310
No indicator- when
selected, a dialog
box appears in
which you enter
values to execute
the command
Tips & Useful Tools
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Using the Information Window
The Information window displays different types of information about a
model
Display
parent and
child
information
Display
object
information
Set the
information
mode
Display an
object’s
modify
dialog box
Display a
text file
Clear
information
window
Save
information
to a text file
Copy text
Multibody Dynamics A, wb1310
Tips & Useful Tools
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Using the Select List Manager
The Select List manager is used to…
 get a list of selected objects
 add/remove objects from a list
 work with multiple geometries
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Tips & Useful Tools
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