收集的一些关于tire的资料，贴出来大家分享。

paor815

今天没事找了几篇关于tire的问题，给一些需要的朋友，希望对大家有所帮助。另外说一点，不管如何使用tire，你都需要tire的一些数据，而这些数据是很难得到的。就我所知，现在好像只有吉林大学（因为一汽就在旁边）有能力做一些轮胎的试验数据，如果你能认识一些吉大的朋友，或许能得到一些帮助。
下面在了几篇我个人认为比较重要的给大家以参考：

paor815

Article 10107   
Description of the three ways to create a tire in ADAMS for v12/v2003.  

This article applies to ADAMS/Chassis, ADAMS/View, ADAMS/Solver, ADAMS/Car, ADAMS/Driveline, ADAMS/Pre, ADAMS/Motorsports, ADAMS/Tire (12.0, 2003) on all platforms.


--------------------------------------------------------------------------------

Question

How can I create a tire in ADAMS?


--------------------------------------------------------------------------------

Answer

First, I would suggest that you look at "About ADAMS/Tire Products" in the .pdf
documentation. This basically tells you that there are 3 different ways to
create tire forces in ADAMS, although you'll probably find that the last two
are not used very much (and are basically obsolete; they're kept around mostly
for legacy purposes).

The 3 methods are as follows:

1. An "ADAMS/Tire" tire: an STI (Standard Tire Interface) tire; generically to
mean the current generation ADAMS/Tire Handling and ADAMS/Tire 3D
Contact(Durability) products.

2. A TIRE statement tire (recall that a statement is keyword found in a solver
.adm file to define an element understood by solver): ADAMS/Tire - TIRE
Statement or just the TIRE Statement to indicate the preceding generation of
ADAMS/Tire.

3. A 5.2.1 Tire: ADAMS/Tire - 5.2.1 to mean the first generation of ADAMS/Tire
originally released in 1985 (it has a slightly different implementation that
the current "ADAMS/Tire" tires.

So, what you'll find is that the solver manual refers to the TIRE statement
(2), the ADAMS/Car, ADAMS/Chassis (Pre) and ADAMS/Tire manuals refer to an
"ADAMS/Tire" tire (1), and you won't find any current manuals that refer to
5.2.1 Tire (3). You can only get a manual for 5.2.1 in hardcopy by purchasing
one from MSC (unless you are creating a 5.2.1 "ADAMS/Tire" tire - read on for
more details).

Moreover, the methods to make a TIRE statement, a 5.2.1 Tire, and an
"ADAMS/Tire" tire are all different:

- For a TIRE statement: In ADAMS/View, from the "Create Forces" palette,
click on the Tire icon. This creates a TIRE statement. This will bring up the
"Create Tire Force" dialog box. Within this dialog box, you will notice 5 tire
models at the top: (1)Delft, (2)Fiala, (3)Smithers, (4)UA Tire, and (5)User
Defined.

- To create a 5.2.1 tire: In ADAMS/View click on the Tire icon just as you
did to create a TIRE statement. At the bottom of the dialog box you will see
the following: Alternatively - "Create Tire Using General Force ..." No matter
which one of the 5 models are toggled above, this option will always appear.
This is what you should use for the ADAMS/Tire v5.2.1 tire model using the
GFORCE method of implementation. Note that as of v12, you can use a "5.2.1"
tire model with the "ADAMS/Tire" method, so you actually have two ways to
implement this kind of model.  See the ADAMS/Tire guide for more details.

- To create an ADAMS/Tire tire: This is described in detail in the "Using
ADAMS/Tire" guide under "Defining Tires". In ADAMS/Pre or ADAMS/Car, when you
create a wheel element, the multiple solver statements that are necessary are
created automatically. In ADAMS/View, you must create all of the solver
elements (GFORCE's, MARKER's, etc.) manually.   Note that if you need to use a
SWIFT tire in ADAMS/View, you need to create a GSE-based tire.  See KBA 10405
linked below.
***NOTE:  when creating an STI tire, the STRING for "road contact type" (i.e.,
"handling" or "durability") is not used to determine the road contact method
anymore.  It is automatically determined based on the road definitiion.  The
string is still required to define the tire, however.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb10107.dasp

paor815

Article 10108   
Tire property files (.tir and .tpf): common questions.

This article applies to ADAMS/Chassis, ADAMS/View, ADAMS/Solver, ADAMS/Car, ADAMS/Driveline, ADAMS/Pre, ADAMS/Motorsports, ADAMS/Tire (12.0) on all platforms.


--------------------------------------------------------------------------------

Question

I'm trying to learn about tire property files.  I've seen different kinds, and
read about them in different manuals.  Can you give an overview on these
files?


--------------------------------------------------------------------------------

Answer

Here are some commmon questions about this:

Question 1: I would like some clarification regarding the Tire Properties
file.  What is the difference between a .tpf file and a .tir file?

Answer 1:  A .tpf file is a tire property file used by the TIRE statement. See
"Using ADAMS/Solver", TIRE statement: "To use the TIRE statement you must
supply a tire property file (.tpf) and a road data file (.rdf). The tire
property file contains parameters, such as cornering stiffness, that
ADAMS/Solver uses to calculate tire forces." You can still use a TIRE
statement in View, but it is not prefered; ADAMS/Tire is prefered, but you
must define the elements needed for an ADAMS/Tire tire, as defined in
"Defining Tire" of "Using ADAMS/Tire. You can even use a TIRE statement in
ADAMS/Car, but it would be very difficult and cumbersome to do, as the
ADAMS/Car .adm file would have to be editted by manually to add the TIRE
statement. This is strongly discouraged, as the method of implementing a tire
using ADAMS/Tire in ADAMS/Car is much easier, prodived better solutions, and
is more flexible. A .tir file is a tire property file used by ADAMS/Tire, the
current and prefered method of creating a tire. See the ADAMS/Tire
documentation for more details on this.

Q2:  There are 3 places that tires are talked about: 1) In ADAMS/Chassis (Pre)
and ADAMS/Car,  2) In ADAMS/Tire 3) In ADAMS/Solver.   In 1) the ending is
stated to be ".tir" and uses the "TiemObject" Format.

A2. Yes, in ADAMS/Chassis (Pre), ADAMS/Car and  ADAMS/Tire the usual ending is
".tir" for the TiemOrbit format. However, you could theoretically put whatever
suffix you want, it's just that by expecting a .tir file, it makes
searching/browsing for these files easier. You *could* potentially find other
tire property files with different suffixes -- in this case, just look at the
contents of the file to find out what kind of tire property file it is. The
TIRE statement should describe what kind of tire property file it wants
(usually ending in .tpf), ADAMS/Tire lets you know the format that it wants
(usually .tir), and 5.2.1 Tire explains what kind of tire property file it
wants.

Q3: In the "Using ADAMS/Solver" guide, it talks about the Analytic format to
be used with the FIALA model, but this is different from the "TiemObject"
Format and also refers to the ending as ".tpf".

A3: Yes, a TIRE statement expects a ".tpf" file, the same as those found in
the "$install_dir/solver/tire_dat" directory. The format of the TIRE statement
tire property file is different than the Tiem Orbit format for ADAMS/Tire.

Q4:  I've read that if  you're using ADAMS/Tire, you want to use the Tiem
Orbit format.  However,  ADAMS/Tire is not a module you run like ADAMS/Car or
ADAMS/Chassis (Pre). So if I am using the solver TIRE statement my tire
property format must not be in TiemOrbit format but Analytical for the FIALA
model?  

A4:  Yes, ADAMS/Tire is built into the solvers (standard solver, acarsolver,
apresolver), and it expects the Tiem Orbit format tire property files.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb10108.dasp

paor815

Article 12385   
How to add an ADAMS/Tire tire to your ADAMS/View model (v2003)
This article applies to ADAMS/View, ADAMS/Solver, ADAMS/Tire (2003) on all platforms.


--------------------------------------------------------------------------------

Question

I'd like to include a tire model in my ADAMS/View model. How do I do this in version 2003 with ADAMS/Tire?

--------------------------------------------------------------------------------

Answer

This article provides an update for the Tire-builder custom dialog box documented in Knowledge Base article 9541. A custom dialog box is provided to facilitate building Tires in ADAMS/View v2003.

Here is an example of using the custom Tire-builder dialog box in ADAMS/View to incorporate an ADAMS/Tire tire in your model. Using the attached example file example_start.cmd you should be able to work through using the dialog box to create a valid Tire. This method can then be applied to your own model.

Setting up
Download the example model file example_start.cmd from the bottom of this article. Download the tire_builder.zip file from the bottom of this article for your version of ADAMS. Unzip the file and place all the files in your current ADAMS/View working directory. If you are working on Unix then you may need to use the dos2unix utilities to strip linefeeds from the Windows files.

Creating reference markers
The Understanding the Basics of Using ADAMS/Tire guide explicitly indicates the directions for the wheel reference marker and the road reference marker in the section Tire Axis Systems. If you are using your own model you must create the tire and road reference markers with the proper orientation. The example model attached to this article contains two markers named wheel_center_ref and road_ref that should have the correct orientation.

Loading the dialog box
Hit 'F2' in ADAMS/View and read in the file import_dialog_box_and_macro.cmd. You should now have the Tire builder dialog box displayed. Note that each field has a helpful 'tooltip' to describe what should be in the field. For the example model the dialog box will look like so:

Hitting Ok or Apply will create the required GFORCE, DIFF, STRING and other elements in your ADAMS/View model.

Running the model
Unfortunately these Tire models won't run properly inside of ADAMS/View for version 2003 of ADAMS. You must run the model using External Solver within ADAMS/View or save a .adm file and run the model on the command line. Change the Solver Executable to be External Solver inside of ADAMS/View if you are using the example model and then run the simulation script named run_tire in the model. The simulation should show the tire start to slowly start rolling. The sphere is 'floating' due to the tire element and the REQUESTs in the model contain tire data that might be useful in a real model.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb12385.dasp

这是这篇文章的附件:

paor815

Article 9541   
How to add an ADAMS/Tire tire to your ADAMS/View model.
This article applies to ADAMS/View, ADAMS/Solver, ADAMS/Tire (12.0, 11.0) on all platforms.


--------------------------------------------------------------------------------

Question

I'd like to include a tire model in my ADAMS/View model.  How do I do this in
version 11 with ADAMS/Tire?


--------------------------------------------------------------------------------

Answer

You need to do two things:

1. Create the elements in your model which represent your tire
2. Create or provide a subroutine to calculate the tire force and moments

The elements required for step 1 are defined in "Defining Tires" of "Using
ADAMS/Tire".  Please see the documentation for details.  Note that you can
also use the attached custom dialog box which will create these elements for
you.  However, this custom dialog box is not officially supported, so please
use this at your own risk. Please verify that it creates the proper elements
for your model.   To use the custom dialog box, please see the guide
"Automating Your Work in ADAMS/View".  Also, see KBA 7099 linked below.

Once that is done, there are two different ways to implement step 2:

A.  using a built-in tire subroutine (ADAMS/Tire)
B.  using a custom tire subroutine

A.  If you're using a built-in tire subroutine:

v2003 and v12:

The ADAMS/Tire routines have been included in the standard ADAMS/Solver.  You
do not need to do anything special (e.g., you do not need to link in atire.f,
as in v11).

v11:

The proper way to use ADAMS/Tire in v11.0 is to use it with the standard
solver.  See the Release Notes for v11.0 on page 55:

http://www.mscsoftware.com/support/prod_support/adams/documentation/110WNRN03.pd
f

Everything has been switched over to .dll's for v11.0, so the standard solver
simply needs the tire subroutines included in a user library.  The steps to do
this are outlined on pages 28-29 of Using ADAMS/Tire; however, going through
the documentation, it is very confusing/incomplete/incorrect since it was
written from a Unix perspective, which doesn't always work for Windows.

Basically, you just need to create an object file from the atire.f subroutine
found in <install_dir>/solver/atire (i.e., df /c atire.f)

Next, you need to create a .dll from this object file (i.e., adams11 cr-user n
atire.obj -n mysol.dll exit)
  
Finally, when you submit a simulation, you need to reference this .dll (i.e.,
adams11 ru-user mysol.dll)

B.  If you're using your own tire subroutine:

You will need to use ADAMS/Car for this (create your own private ADAMS/Car
solver routine), as specified on page 57 of the 11.0 Release Notes.

http://www.mscsoftware.com/support/prod_support/adams/documentation/110WNRN03.pdf

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb9541.dasp

这是这篇文章的附件:

paor815

Article 8382   
How to convert TIRE statement tires to "ADAMS/Tire" (GFORCE) tires.

This article applies to ADAMS/View, ADAMS/Solver, ADAMS/Tire (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

I have a model with tires that were created using the TIRE statement. However,
you suggest that we use an STI-based ("ADAMS/Tire") tire (based on a GFORCE).
How can I do this?


--------------------------------------------------------------------------------

Answer

You must delete the TIRE statement and then create the GFORCE and associated
statements, as detailed in "Using ADAMS/Tire", "Defining Tires".

There are 2 methods to create the GFORCE and associated statements for an
ADAMS/Tire tire, as specified in "Defining Tires":

1. create the entities from within View
2. manually edit the .adm file to create the statements (the entities)
3. use the attached custom dialog box which will create these elements for
you.  

To use the custom dialog box, please see the guide "Automating Your Work in
ADAMS/View".  Also, see KBA 7099 linked below.  Note that the custom dialog
box is not officially supported, so please use this at your own risk. Please
verify that it creates the proper elements for your model.

For more information, see the KBA's linked below.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb8382.dasp

这是这篇文章的附件:

paor815

Article 7844   
Example model using TIRE statement.

This article applies to ADAMS/View, ADAMS/Solver (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

I am working with a TIRE statement and I need a simple example to get me
started. Do you have anything like that?


--------------------------------------------------------------------------------

Answer

Attached is an example of a simple bike model with two tire forces. To run
through this example:

[0] Extract the tire, road, and model files:
      frt.tpf (895)
      rr.tpf  (904)
      road.rdf (483)
      bike.cmd (10296)

[1] Import the model "bike.cmd". (The tire and road files will get
    loaded automatically.)

[2] Simulate the model using script, as follows:

      Simulate - Scripted Controls
      Simulation Script Name: .model_1.SIM_SCRIPT_1

[3] Animate the results, notice the effect of the steering input.

     Review - Animation Controls
     Base Part: .model_1.Frt_steer_wheel

Note, some tire property files for the TIRE statement and another example can
be found in the ADAMS distribution. These files are included in the
installation directory:

  /your_install_dir/solver/tire_dat/*.TPF and *.TOF
  /your_install_dir/solver/samples/uatire.adm

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb7844.dasp

这是这篇文章的附件:

paor815

Article 7681   
TiemOrbit and .TIR tire property files.

This article applies to ADAMS/Solver, ADAMS/Tire (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

What is the .TIR file format? What is the TiemOrbit Neutral File for tire
models? Where can I find examples and information about the .TIR format?


--------------------------------------------------------------------------------

Answer

The .TIR file format is the newer TiemOrbit style tire property file
used by ADAMS/Tire. Previous versions of ADAMS/Tire used .TPF tire property
files, which were specific to ADAMS.

You can find information about the TiemOrbit file format in "Using ADAMS/Tire"
documentation.  You can also look through some example files, and get an idea
for how each characteristic is used.

Example .TIR files are located in:
  <install_dir>/acar/shared_car_database.cdb/tires.tbl/
  <install_dir>/solver/atire/

The .TIR files have a separate block which identifies units so parameters are
given in the units defined. In the older tire property file format, each
characteristic had a conversion factor in addition to the actual parameter.

The parameters in the tire property files were determined by laboratory
testing, so we generally do not recommend users modify them by hand, since
that can lead to inaccurate results. However, some common parameters which can
be modified with a lower chance of producing problems are vertical stiffness
and cornering stiffness.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb7681.dasp

paor815

Article 8869   
What is STI (Standard Tire Interface)?

This article applies to ADAMS/Chassis, ADAMS/View, ADAMS/Solver, ADAMS/Car, ADAMS/Driveline, ADAMS/Pre, ADAMS/Motorsports, ADAMS/Tire (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

What is STI?


--------------------------------------------------------------------------------

Answer

STI is the "Standard Tire Interface", which is basically a standardized set of
parameters that are used to describe tire models.  They were put into place by
the TYDEX consortium in order to allow anyone to develop a tire model and be
able to share the data.  From "Using ADAMS/Tire", page 114, this is what we
have for STI:

Standard Tire Interface (STI)
As a result of the First International Colloquium on Tire Models for Vehicle
Dynamics Analysis on October 21-22, 1991, the international Tire Workshop
working group was established (TYDEX).  The working group concentrates on tire
measurements and tire models used for vehicle simulation purposes. For most
vehicle dynamics studies people usually develop their own tire models. Since
all car manufacturers and their tire suppliers have the same goal (that is
development of tires to improve dynamic safety of the vehicle) standardization
in tire behavior description should be aimed for.

In TYDEX two expert groups were defined with following goals:


The first expert group (Tire Measurements - Tire Modeling) has as its main
goal to specify an interface between tire measurements and tire models. The
work shall include a description of the test conditions. The interface could
be described as a definition of a method or format to describe tire
measurement data in such a way that it contains all necessary items to fit
tire models to the underlying data. The format shall also allow for a
description of the test conditions.


The second expert group (Tire Modeling - Vehicle Modeling) has as its main
goal to specify an interface between tire models and simulation tools.
Intentionally, use of this interface will ensure that a wide range of
simulation software can be linked to a wide range of tire software available.

Both expert groups consist of participants of vehicle industry (passenger cars
and trucks), tire manufacturers, other suppliers and research laboratories.
The large number of participants indicates that there is a need for this kind
of standardization work. DVR is strongly involved in TYDEX.

At the moment, a concept for the description of the Tire Modeling - Vehicle
Modeling interface have been developed and will be tested within the different
companies. This interface is named the Standard Tire Interface (STI) [2].  The
Standard Tire Interface prescribes a subroutine call with a number of
subroutine arguments to pass all relevant information from tire models to
multi-body programs and vice versa. The subroutine represents a shell around
tire software and is fixed to the axle hub which is modeled by the multi-body
programs.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb8869.dasp

paor815

Article 10109   
Comparison between TIRSUB and TYRSUB.

This article applies to ADAMS/Chassis, ADAMS/View, ADAMS/Solver, ADAMS/Car, ADAMS/Driveline, ADAMS/Pre, ADAMS/Motorsports, ADAMS/Tire (12.0) on all platforms.


--------------------------------------------------------------------------------

Question

There seems to be 2 references to tire subroutines: TIRSUB and TYRXXX. From
what I can gather if in the TIRE statement MODEL=USER then the default or your
own TIRSUB will be called. But if in the tire property file (TiemObject
format) the PROPERTY_FILE_FORMAT = 'USER' and USER_SUB_ID=XXX then TYRXXX will
be called. What is the difference between TIRSUB and TYRXXX? It seems that
TRYXXX must do everything (read in tire properties and road properties, etc.)
while TIRSUB needs only calculate forces and torques from the tire properties
(postion, angle, rotational speed) returned to it. Is this on the right track?



--------------------------------------------------------------------------------

Answer

Yes, you are on the right track with the subroutines: a TIRSUB corresponds to a
TIRE statement (see Using Subroutines in the ADAMS/Solver section). A TYRSUB
(TYRXXX) corresponds to ADAMS/Tire (see the ADAMS/Tire docs).

For example: TIRSUB is a user-written tire-terrain force evaluation
subroutine. It defines a set of three forces and three torques acting at the
tire-terrain contact point. TIRSUB requires that the forces and torques be
computed in the SAE coordinate system for the tire. ADAMS/Solver takes the
force and torque values at the contact patch and transfers them to the tire
hub center.

On the other hand, all TYRSUBs must perform these tasks:

1 Read any data it requires from the tire property file.

2 Call the ROAD subroutine to initialize the road model and to determine the
road location, local road normal, and road coefficient of friction.

3 Calculate the tire forces and moments in units of Newtons and Newton-meters
and return them to ADAMS/Tire at the wheel center in the ISO-C axis system
(see About Axis Systems and Sign Conventions on page 35 in the guide, Using
ADAMS/Tire).

4 Load results, such as slip angle, in the VARINF array for plotting.

5 Handle errors. For example, report when needed data is missing from the tire
property file.

So, if you use the statements ... GFORCE/1 , I = 1 , JFLOAT = 2 , RM = 3 ,
FUNCTION = USER(900,1,100) ... The solver will automatically know that
USR(900,..) is a tire call and will use the internal model specified in the
tire property file (TiemObject format).  Any subroutine numbered between 900 -
999 is an ADAMS reserved subroutines (users can specify subroutines numbered
from 001-899). 900 is the ADAMS/Tire subroutine(TYRSUB).

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb10109.dasp

paor815

Question:
view中轮胎力和car,chassis中的轮胎有何区别

Answer By johnson_liao :
你這個問題, 絕對可以在ADAMS/Tire R12 manual 找到.

About ADAMS/Tire - Handling and Durability
===========================
The current generation of ADAMS/Tire is integrated into ADAMS/Car and
ADAMS/Chassis, but you can also use it with ADAMS/Solver by linking an
ADAMS/Solver user library. If you are not using ADAMS/Car or ADAMS/Chassis,however, you must define a set of ADAMS statements in your model using ADAMS/Viewor a text editor to invoke ADAMS/Tire.

About ADAMS/Tire - TIRE Statement
The previous generation of ADAMS/Tire, the TIRE statement, is not integrated into ADAMS/Car and ADAMS/Chassis. You can, however, define a TIRE statement in your model using a dialog box in ADAMS/View.
The TIRE statement is documented in the guide, Using ADAMS/Solver, in the sections:

TIRE on page 469

Using Tire Statement on page 973
Anyone with a license of ADAMS/Solver can use the TIRE statement with the Fiala tiremodel. To use the University of Arizona (UA) tire model, Delft-Tyre 5.0, or the Smithers tire model with the TIRE statement, you must have a license of ADAMS/Tire-Handling.

About ADAMS/Tire 5.2.1
The first-generation ADAMS/Tire product: ADAMS/Tire 5.2.1, includes the Equation Method and Interpolation Method for calculating handling forces and the 2D Equivalent Plane method for calculating tire-road contact forces.
To use ADAMS/Tire 5.2.1, you must have a license of ADAMS/Tire-Handling. ADAMS/Tire 5.2.1 is not integrated into ADAMS/Car, ADAMS/Chassis, or ADAMS/Solver. ADAMS/View does include a dialog box that creates either a set of six SFORCEs per tire or a single GFORCE for use with ADAMS/Tire 5.2.1. Before using ADAMS/Tire 5.2.1, you must link an ADAMS/Solver user library.The documentation for ADAMS/Tire 5.2.1 is available in in the guide, Using ADAMS/Tire.

这是这篇文章的链接(下面如同):
http://www.simwe.com/forum/viewthread.php?tid=123269

paor815

Article 9241   
Initial velocity of tires.

This article applies to ADAMS/View, ADAMS/Car, ADAMS/Tire (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

I would like to include tires on my vehicle model.  Do the initial velocities,
including the spin velocities or the tires, have to be specified?


--------------------------------------------------------------------------------

Answer

In ADAMS/View, if you want to have your vehicle run at a certain
velocity at time t=0.0 in your dynamic analysis, then you
need to supply an initial velocity for all parts (excluding
ground). For all the tires, you need to supply the appropriate
rotational velocities as well (depending on their radii).

In ADAMS/Car, the initial spin velocities of the tires are automatically
calculated based on the initial velocity of the vehicle

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb9241.dasp

paor815

Article 7994   
Very high slip ratio at initial time step.

This article applies to ADAMS/Tire (no specific release) on all platforms.


--------------------------------------------------------------------------------

Question

I created a full vehicle model using the ADAMS/Solver TIRE statement with the
FIALA tire and the default flat road profile. The simulation
is supposed to introduce a step steering wheel angle input into the vehicle
moving straight forward at a constant speed. The simulation was achieved at
static equilibrium but failed in dynamic simulation. Attached is one of many
warning messages from .msg file,

TSLIP:TRIM_SS

---- WARNING ----
   For TIRE cr_mditire.TIR1 the absolute value of the longitudinal     
   slip ratio
   has gone beyond its maximum allowable limit of 1.0.

   Longitudinal slip ratio = 2490.6.

   If the longitudinal slip ratio is positive, it will be set
   to 1.0 (braking).  If the longitudinal slip ratio is
   negative, it will be set to -1.0 (traction).
   
   
Those parameters of .adm and .tpf and .rdf files are very representative of
real vehicle data. I'd like to know what will cause the huge longitudinal slip
ratio from the model (tire, road ...?). Hope you can help me out. Thanks in
advance.



--------------------------------------------------------------------------------

Answer

The warning message you are seeing is caused by an incompatibility between the
tire's rotation speed and translational speeds at the initial time.

This is most likely caused by a translational initial condition on the vehicle
but no rotational initial conditions on the tires. That is, at the first time
step, the vehicle is already in motion, but the tires are not, therefore
during the first time step, the vehicle is in a locked skid. This causes large
and unnecessary forces at the contact patches.

You can prevent this from happening by either starting the vehicle from a
standstill, or by specifying a rotational initial condition on the tires. You
can start the simulation with no initial velocity on the vehicle, and smoothly
accelerate the vehicle to experimental velocity, OR you can determine the
circumferential speed of the tires at the vehicles initial velocity, and apply
the corresponding rotational initial condition to your tires, so at the start
of the simulation, both vehicle and tires are moving at the correct speed.

Let me also explain what the warning message means. The longitudinal slip
ratio (s) is the ratio between the slip velocity (Vxc) and the road velocity
(Vx) in braking, and contact patch velocity (Vc) in traction. The slip
velocity (Vxc) is the difference between the contact patch velocity (Vc) and
road velocity (Vx). Therefore, at slip ratio values greater than 1, the tire
is in a pure slip, and tire properties no longer apply, which is why ADAMS
will reset the value to 1. As far as the tire is concerned, all values greater
than 1 will have the same effect.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb7994.dasp

paor815

Article 7646   
Slip ratio greater than 1.0.

This article applies to ADAMS/Tire (9.x) on all platforms.


--------------------------------------------------------------------------------

Question

How can slip ratio in my tire model be greater than 1.0? Sometimes it even
amounts to 50.


--------------------------------------------------------------------------------

Answer

Check to see where the results are coming from. Is the slip ratio coming from a
Results (.res) file, or from a subroutine (like REQSUB) where the output
values may be evaluated. For example, it is possible that the slip ratio has
been multiplied by 100 to give a percentage, rather than a fraction, so a slip
ratio of .5 is reported as 50 percent.

这是这篇文章的链接(下面如同):
http://support.adams.com/kb/faq.asp?ID=kb7646.dasp

paor815

已经贴完了。建议大家先搜索论坛中的关于tire或者轮胎等关键词的帖子，毕竟是中文的，而且准对性非常强，也很好理解。如果大家还需要关于类似的文章，给大家一个官方引擎，自己搜索：

引擎链接:
http://support.adams.com/kb/dsearch.asp

附图：

paor815

不知道论坛的回复怎么回事，搜索引擎应该是最后回复的，可是不知道怎么就跑到前面去了，大家自己慢慢看吧。
如果有错误，通知我，我会修改过来。如果哪位网友还有好的帖子，请跟着贴，方便大家查找。

luyang1988

谢谢楼主，太感谢了

逆鳞1989

楼主好人