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Version 1.0 6/18/2008 1
Opening, Working with, and Saving Files in ADAMS/Car
ADAMS/Car Files
In ADAMS/Car Standard Interface you will work with templates that have been created.
Templates are pre-built models that have been created with the pre-set communicators, parts,
parameters, and constraints needed to create vehicle components. The template defines how
ADAMS assembles the various parts and joints to build the vehicle. Templates for FSAE and
Mini-Baja are available on the MSC University website (www.mscsoftware.com/university).
You will need to register on the website to gain access to the templates.
When you download a template you will have a database that has basic subsystems (e.g. front
suspension, steering system) that can be combined into assemblies and simulated in
ADAMS/Car. The database contains the information about the tire, springs, shocks, subsystems
and assemblies used by the model. Below notice the file folders with the .cdb extension. This
extension denotes an ADAMS/Car database.
ADAMS/Car
database folders
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Inside the database are folders with a .tbl extension that group the various files used by
ADAMS/Car. The folder names are indicative of the files found inside the folder. Notice the
assemblies and subsystem folders. These are the files you will open to begin modifying the
templates. Other folders like springs and tires contain property files that define parameters for
the respective folder names. The templates.tbl folder contains the property files which specify
the topology of the system components.
Inside each .tbl folder are text files relating to the folder’s description. The extensions have been
changed for use by ADAMS/Car. Below is the FSAE model assemblies.tbl folder which
contains files having an .asy extension. Files in the subsystem.tbl folder have a .sub extension.
Similarly files in the tires.tbl have a .tir extension.
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The files found in the .tbl folders are text files that contain information about the particular part,
assembly, etc. The assembly file fsae_front_with_steert.asy shown below is the FSAE front
suspension with steering. Opening this file in a text editor shows the contents. The file contains
information ADAMS/Car uses to build the assembly such as units and subsystems contained in
the assembly.
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First things First
When you open ADAMS/Car you will need to perform the following steps to ensure that the
files you will create and use go to the right place and are accessible.
• Add Database to Session
To work with the MSC University templates you will need to download the template file and save
it to a directory to work from. The file should have the .cdb file extension. You then need to add
the database by clicking Tools>Database Management>Add to Session.
To add the database you need the location and the database alias. The alias is a specific name
given to the database and must be entered correctly. The alias should be supplied with the
template. See the tutorials in the Appendix on opening MSC University templates.
• Setting Default Writable Database
ADAMS/Car saves new files to your Default Writable Database. You can create a default
writable database by clicking Tools>Database Management>Create New Assembly. Once the
database is created make it the default writable database by clicking Tools>Database
Management>Set Default Writable. You can choose to make the working database the default
writable (e.g. FSAE or Mini-Baja template databases). To see the current databases click
Tools>Database Management>Database Info.
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• Select Directory
This is Very Important!!
When your perform simulations ADAMS/Car sends the output files to the selected directory. To
set this directory click File>Select Directory and navigate to the folder you wish to store
simulation outputs. The default directory in the computer lab is your L: drive. If your L: drive
fills up, ADAMS will crash. If it is close to full before opening ADAMS, the software will not
open at all. You must change this directory to a folder on the C: drive (the computer’s hard
drive) for these tutorials to work properly. Anything you save to the computer’s hard drive will
be erased when you log off. If you wish to save any material in the working directory, you must
move it to another storage location before you log off the lab computer.
• Setting Units
The University Templates have been created in metric units. You can change the units while you
are working with the model. If you save your subsystem or assembly with different units than
the template ADAMS car defaults back to the template units. If you wish to work with different
units than specified in the templates you must change the units every time you open a subsystem
or assembly. To change the units click Settings>Units.
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To set the units to inches, pounds and seconds click the IPS button and then OK. To select
different units click the dropdown menus, select the units and click OK.
• Help Files To view help files for entering information into dialog windows press F1. The help file will
open in the default web browser to the information relating to the current dialog window.
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Subsystems and Assemblies
With the database added, default writable set and directory selected you have the option to open
a subsystem or an assembly. Each opens components of the template. Subsystems can be
modified but not simulated. In an assembly you modify and perform simulations. When you
open an assembly you are opening a set of subsystems and a test rig. The test rig is an assembly
that allows you to perform simulations. You have the same abilities to modify in either so if you
are planning on simulating it may be easier to open an assembly. If you want to make major
changes and create a new assembly you may want to modify at the subsystem level. Note that
when you open a subsystem or assembly that you are modifying parts that are there. You can not
add or delete parts, but, you can modify masses, joint locations, spring rates, etc. To change a
vehicle’s topology, i.e. how parts and joints are brought together, you must open the template in
Template Builder.
Creating New Subsystems
You can create a new subsystem from an existing
template. This allows you to make changes to an existing
subsystem and also keep the original. To create a new
subsystem click on File>New> Subsystem. The file is
saved in your default writable database.
A dialog box appears and you must enter the Subsystem
Name, Minor Role, Template Name and optionally
Translation Values. The Translation Values allow you to
translate the subsystem along the length of the vehicle.
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Creating New Assemblies
To create a new assembly click on File>New> Assembly. You must specify all of the
subsystems to be in the assembly as well as a test rig. Under the Other Subsystems selection box
you can select multiple subsystems by holding the control button on the keyboard while selecting
the subsystems in the database navigator.
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To create a full-vehicle assembly click on File>New> Full Vehicle. The requirements for a
new full-vehicle assembly are a front suspension, rear suspension, front and rear tires, a steering
system, and a test rig. To perform the canned simulations that ADAMS/Car provides select the
_MDI_SDI_TESTRIG.
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Replacing Subsystems
While working with an assembly you have the ability to replace a subsystem. This can be useful
for testing different suspensions without creating a completely new vehicle. To replace a
subsystem with another click File>Manage Assemblies>Replace Subsystem.
When the dialog window appears select a subsystem to replace from the dropdown menu then
navigate to the system you want to replace it with.
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Subsystems Found in FSAE and Mini-Baja Templates
Here are the subsystems found in the FSAE template.
Here are the subsystems found in the Mini-Baja template
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Assemblies Found in FSAE and Mini-Baja Templates
Here are the assemblies found in the FSAE template.
Here are the assemblies found in the Mini-Baja template.
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When you open an assembly ADAMS opens all of the subsystems and parts that make up the
assembly. When a subsystem file is read ADAMS/Car reads the topology from the templates
referenced in the subsystem header. The subsystems and parts are connected via input and
output communicators. You may get communicator errors when opening assemblies. For the
provided templates this shouldn’t be a problem because not all communicators are required for
simulation. The errors can however provide insight in to problems in the model.
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Saving Assemblies
To save your assemblies click File>Save.
When you save an assembly ADAMS/Car may alert you that the assembly or a subsystem file
already exists and ask whether or not to you wish to create a backup copy.
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If you select yes to creating a backup ADAMS/Car saves a copy of the original file with the “q”
replacing the last letter of the extension. If warning messages asks you to create a backup copy
and a backup copy has already been created ADAMS/Car will not write over the existing file
backup file.
Assembly backup file
Subsystem backup file
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Pan, Zoom, Rotate & Preset Views
To navigate the model space for better perspective on a subsystem or assembly right click in an
empty area of the window to view your options. There are preset views to select from and
dynamic options for use with the mouse. Keyboard shortcuts for these viewing commands are
shown beside each option. The most common shortcuts are “r” + left mouse button to rotate and
“t” + left mouse button to translate.