Getting Started Using ADAMS/Controls

120 Pages·2002·1.23 MB·English

Getting Started
Using ADAMS/Controls
About this Guide 3
Learning the Basics 5
Introducing and Starting the Tutorials 11
Learning ADAMS/Controls with MATLAB 29
Learning ADAMS/Controls with Control System Import 45
Learning ADAMS/Controls with EASY5 57
Learning ADAMS/Controls with MATRIXx 77
Setting Simulation Parameters 101
Advanced Topics 107
2 Getting Started Using ADAMS/Controls
Copyright
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government contract, then they are provided with RESTRICTED RIGHTS. Use, duplication or disclosure is
subject to restrictions stated in paragraph (c)(1)(ii) of the Rights in Technical Data and Computer Software
clause at 252.227-7013. Mechanical Dynamics, Incorporated, 2300 Traverwood Drive, Ann Arbor, Michigan
48105.
The information in this document is furnished for informational use only, may be revised from time to time, and
should not be construed as a commitment by Mechanical Dynamics, Incorporated. Mechanical Dynamics,
Incorporated, assumes no responsibility or liability for any errors or inaccuracies that may appear in this
document.
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Dynamics, Incorporated.
©2002 by Mechanical Dynamics, Incorporated. All rights reserved. Printed in the United States of America.
ADAMS ® is a registered United States trademark of Mechanical Dynamics, Incorporated.
All other product names are trademarks of their respective companies.
Part number: 120CTGS-01
Getting Started Using ADAMS/Controls 3
About this Guide
About this Guide
Welcome to ADAMS/Controls
ADAMS/Controls is a plug-in to MDI’s ADAMS/Car, ADAMS/Chassis, ADAMS/Rail,
ADAMS/View, or ADAMS/Solver that helps you add sophisticated controls to your
ADAMS model. ADAMS/Controls lets you connect your ADAMS model to block
 
diagrams that you’ve developed with control applications such as EASY5 , MATLAB ,

or MATRIX .
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ADAMS/Controls offers you the option of:
(cid:1) Simulating the combined mechanical system and controller entirely within the
controls application,
(cid:1) Simulating entirely within ADAMS, or
(cid:1) Solving the controls equations with the control package and solving the
mechanical system equations with ADAMS.
ADAMS/Controls also lets you interactively view the simulation results in ADAMS/Car,
ADAMS/Chassis, ADAMS/Rail, and ADAMS/View.
What You Need to Know
This guide assumes that you know how to run ADAMS/View or ADAMS/Solver. It also
assumes that you have a moderate level of proficiency with one of the controls packages
with which ADAMS has an interface. These include: EASY5, MATLAB, or MATRIX .
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To use ADAMS/Controls, you need access to one of these controls packages so that you
can prepare a controls block diagram, add it to your mechanical model, and simulate the
combined system.
For information on other MDI products, see the online Road Map to ADAMS
Documentation.
4 Getting Started Using ADAMS/Controls
About this Guide
1 Learning the Basics
Overview
ADAMS/Controls helps you connect your ADAMS
mechanical system models to block diagrams developed with
EASY5, MATLAB, or MATRIX . This chapter introduces
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you to ADAMS/Controls and the basics of its interface
features. It contains the following sections:
(cid:1) How You Benefit from Using ADAMS/Controls, 6
(cid:1) How to Improve the Design Process with
ADAMS/Controls, 6
(cid:1) Ways in Which You Can Use ADAMS/Controls, 8
(cid:1) About the ADAMS/Controls Four-Step Process, 9
(cid:1) How to Learn ADAMS/Controls, 10
6 Getting Started Using ADAMS/Controls
Learning the Basics
How You Benefit from Using ADAMS/Controls
By combining mechanical system simulation tools and controls design tools, you can:
(cid:1) Add sophisticated controls to an ADAMS model and simulate the combined
system.
(cid:1) Generate mechanical system simulation models directly from your ADAMS
data without having to write equations.
(cid:1) Analyze the results of your simulation in the ADAMS environment or the
controls application environment.
How to Improve the Design Process with ADAMS/Controls
In the typical design process of a mechanical system with controls, the mechanical
designer and the controls designer work from the same concept, but use different sets of
software tools. The result is that each designer produces a model for the same problem.
Each design is then subject to verification and testing, and the first time the two designs
are brought together is during physical prototype testing. If a problem occurs during the
interaction between the controls design and the mechanical design, the engineers must
refine the control design, the mechanical design, or both, and then go through the entire
verification process again as shown in Figure1 on page 7.
Getting Started Using ADAMS/Controls 7
Learning the Basics
Figure 1. Design Process Before ADAMS/Controls
With ADAMS/Controls, the two designers can share the same mechanical model. They
can also verify from one database the combined effects of a control system on a nonlinear,
non-rigid model. The physical testing process is greatly simplified, and the risk of having
a control law that is developed for the wrong mechanical model is eliminated as you can
see in Figure2 on page 8.
8 Getting Started Using ADAMS/Controls
Learning the Basics
Figure 2. Improved Design Process with ADAMS/Controls
Ways in Which You Can Use ADAMS/Controls
You can use ADAMS/Controls in the ways listed below. The simulation method you
choose, interactive or batch, determines which application you use.
(cid:1) ADAMS/Car, ADAMS/Chassis, ADAMS/Rail and ADAMS/View - By using
ADAMS/Controls with one of these products, you can animate your model and
view the effects of the control system and any structural modifications you
make. This is the application you use if you are running an interactive
simulation.
(cid:1) ADAMS/Solver - For faster simulation results, you can run ADAMS/Controls
directly with ADAMS/Solver, MDI’s powerful analysis engine. This is the
application you use if you are running a simulation in batch mode.
Getting Started Using ADAMS/Controls 9
Learning the Basics
Note: You also have the option with ADAMS/Controls to export either a linear or
nonlinear version of your ADAMS plant to the controls application, or to import
the controls system definition into ADAMS. Importing the control system

requires Mathwork’s Real-Time Workshop .
About the ADAMS/Controls Four-Step Process
The diagram in Figure3 describes the four-step process of combining controls with a
mechanical system. The tutorials in this guide walk you through the detailed procedures
for each step.
Figure 3. ADAMS/Controls Four-Step Process
Step One:
Build the
ADAMS
model. S tep Two: S tep Three: Step Four:
Identify the B uild the control Simulate the
ADAMS inputs and system block model.
outputs and export
diagram.
the plant model.
(cid:1) Step One: Build the Model - The first step in working with ADAMS/Controls
is to build or import an ADAMS model. The model should be complete and
include all necessary geometry, constraints, forces, and measures.
(cid:1) Step Two: Identify the ADAMS Inputs and Outputs - Define the inputs
and outputs through the information or startup file in your ADAMS
product. The outputs describe the variables that go to the controls
application (the output from the ADAMS model is the input to the controls
system). The inputs describe the variables that come back into ADAMS (the
output of the controls application) and, therefore, complete a closed loop
between ADAMS and the controls application. All inputs and outputs must
be set up as variables. Optionally, export the plant system files from
ADAMS for use in the controls simulation software.
10 Getting Started Using ADAMS/Controls
Learning the Basics
ADAMS/Car,
ADAMS Input ADAMS Output
Chassis, Rail, or View
or ADAMS/Solver
Controls
Controls Output Application Controls Input
(cid:1) Step Three: Build the Block Diagram - Build the control system block
diagram with one of the following applications: EASY5, MATLAB, or
MATRIX . Include the ADAMS plant in your block diagram, or if using
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Real-Time Workshop, export the controls system and import into ADAMS.
(cid:1) Step Four: Simulate the Model - Simulate the combined mechanical
model and control system. Several different methods are available to run
your simulation.
How to Learn ADAMS/Controls
This guide introduces you to the most basic concepts of Using ADAMS/Controls through
a series of tutorials. You begin learning ADAMS/Controls with Chapter 2, Introducing
and Starting the Tutorials. This material explains the basics of the ADAMS side of the
ADAMS/Controls interface. After you complete Chapter 2, you continue with the tutorial
that is associated with the specific controls application you are using, including EASY5,
Control System Import, MATLAB, or MATRIX .
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