New Tire formulations for ADAMS Tire Handling and ADAMS Tire Motorcycle Tire

MF-Tyre (Delft-Tyre) in ADAMS Tire Handling has been replaced with PAC2002. PAC2002 has the same functionality, but with improved modeling of the overturning moment. In ADAMS/Tire Motorcycle, Tire MF-MCTyre has been replaced with PAC MC Tire. PAC MC Tire has same functionality, but with improved modeling of the overturning moment.

A C-code tire model has been implemented in both ADAMS/Tire and ADAMS/Car RealTime. The functionality and results are the exact same as the FORTRAN-based PAC2002. The differences in the tire property file are:

• For PAC2002 (FORTRAN), set:

  $----------------------------------------------------------------model
  [MODEL]
  PROPERTY_FILE_FORMAT     ='PAC2002'
          

• For PAC2002 (C-Code), set:

  $----------------------------------------------------------------model
  [MODEL]
  PROPERTY_FILE_FORMAT     ='PAC_CT'
  

For more information, see the ADAMS/Tire documentation.

A nonlinear vertical tire stiffness has been introduced into the 5.2.1 Tire model

The tire vertical stiffness can be described using a spline (force versus deflection) in the MSC.ADAMS dataset. The user array is used to switch between tire property file stiffness and spline stiffness. If the first value in the user array is equal to '5215', the spline vertical stiffness is used. The second value of the user array refers to the IDF of the spline. The message 'Using spline data for the vertical spring' is shown in the message file. If the first value in the user array is not equal to '5215', the tire property file stiffness is used.

Example using the spline vertical stiffness:

! adams_view_name='spline_vertical_stiffness'
SPLINE/10
, X = -1,0,10,30
, Y = 0,0,2000,6000
!
! adams_view_name='wheel_user_array'
ARRAY/102
, NUM=5215,10

SWIFT-Tyre now supports 3D road modeling with TNO road description and ADAMS/3D Road

For more information, refer to the ADAMS/Tire documentation.

Documentation Improvements

ADAMS/Tire Improvements

The ADAMS/Tire documentation has been updated for the new features, including the new tires, PAC2002 and PAC MC Tire. It has also been converted to HTML format so you can use the standard and global searches to locate information. Note that 521 and SWIFT-Tyre are still in PDF format.

Overall Documentation Improvements

For MSC.ADAMS 2005, we've made improvements to the MSC.ADAMS help:

• Added global search so you can search across the entire set of MSC.ADAMS help. To access the global search, do one of the following:

  • At the top of the help, select Switch Products, and then select the Search tab.

  • In any product, select the Search tab, and then in the window that appears, select Global Search.

  Note that the global search does not include any .pdfs (including getting started guides and ADAMS/Driver).

• Removed any hardcoding of font sizes so you can scale the text of the help to any size. Please note that many of the equations do not scale because they are images, and the help looks the best when viewed with medium (or 100%). In addition, your browser will print the text the same size as it is displayed.

• Documented many of the environment variables for the products to help customize your session. The environment variables are for ADAMS/Controls, ADAMS/Durability, ADAMS/Flex, ADAMS/Solver, ADAMS/View, and the template-based products (ADAMS/Aircraft, ADAMS/Car, ADAMS/Driveline, ADAMS/Rail). For more information, see the Running and Configuring help.

New GFORCE/GSE Tire Interface

A new method (GFORCE/GSE908) for tires associated with wheel parts is used to better handle differential equations associated with tires. Instead of a GFORCE and set of DIFF statements, tires are now represented by a GFORCE and GSE (general state equation). The GSE integrates the tire states, offering greater flexibility because you can set the number of differential equations using one parameter. The use of the GSE typically results in fewer evaluations of a tire model in ADAMS/Solver, particularly for tires that do not have states associated with them. Therefore, CPU usage is reduced. In ADAMS/Car, the differential equation associated with the tire's longitudinal slip state is now integrated within the GSE.

Old vpg_tire objects (GFORCE/GSE900) should be replaced by the new vpg_tire objects (GFORCE/GSE908). When you import a model or template containing vpg_tire objects, ADAMS/Car or ADAMS/View replaces the old tires with the new ones.

Standard Tire Interface Changes

The stiTire interface code has been updated with dynamic memory allocation. This offers the following features:

• No limit on the number of tires.

• No limit on the number of states used by the tire model (can even be specified in the tire property file), very useful for more complex loaded radius calculations.

• No limit on number of datapoints in 521 road.

• In ADAMS/View, the tire and road property files are read again when you restart a simulation using the Reset to input configuration tool and then the Simulation Start button from the Simulation palette.

• Supports new GFORCE/GSE908 tire method

No specific items.