ADAMS/Aircraft Release Notes

New taxi simulation input option that increases control over simulations

Taxi conditions submitted for simulation were grouped together as sets of conditions defined by nested loops over a set of road profiles, aircraft configurations, and taxi speeds. Once a set of conditions is submitted, all possible combination of roads, configurations, and speeds are simulated. A new option allows you to:

• Individually pick the conditions to run out of a full set of conditions.

• Individually define simulation durations and pilot inputs files for each condition.

• Capture almost all taxi simulation input in a single file.

These changes are implemented in the aircraft test rig and the taxi simulation macros and dialog box.

Catapult pre-launch input options improved

The launch/holdback geometry parameters have been moved from a separate dialog box into the catapult-prelaunch submittal dialog box and input file. We added new input options to allow you to turn off the external, artificial balance-simulation dampers. These changes improve simulation control and make it easier to repeat past simulations.

Removed the separate launch parameters dialog box.

These changes are implemented in the aircraft test rig and in the catapult prelaunch macros and dialog box.

Assembly aggregate mass communicator added to aircraft test rig

New method to view files

A method to view standard ADAMS/Aircraft road files (.rdf) and taxi roadcase files (.rcf) has been added under the View in the Standard Interface main menu. Before this option was added, the easiest way to see a road profile was to run an analysis using the road. Note that roads not typically used in ADAMS/Aircraft, such as ADAMS/3D Roads, cannot be viewed with this new viewer.

New term for side-force calculation

A new term has been added to the side-force calculation in the ADAMS/Aircraft Enhanced Tire Model. A rolled tire with a vertical velocity experiences a lateral velocity in the tire contact patch, which can generate a side load.

A new option, LAT_SLIP_MODE, has been added to the tire property files to enable this new calculation. For an example, see the shared database tire property file, AA_large_enha_mod.tir, which includes a new parameter that turns on this feature.

Flexible body swap

Added the ability to swap either a rigid part with a flexible part or an existing flexible part with a new flexible part. This utility guides you in selecting the proper node IDs for attachment.

Before this release, you had to create a new template if you wanted to include flexible parts. Now, modal flexibility becomes a property of the MSC.ADAMS body. Therefore, introducing flexible bodies becomes a Standard Interface operation and is reflected in the subsystem file.

There are multiple benefits in delegating the creation of flexible bodies to the Standard Interface.

These include:

• Avoid multiplication of templates
• Avoid use of unnecessary massless interface parts to ensure connectivity
• Automatic transfer of constraints
• Advanced tools to help detection and transferring of connections from rigid body to flex body nodes

To access this feature, use the Rigid to Flex button in the part modify dialog box.

Documentation Enhancements

ADAMS/Aircraft Documentation Improvements

Added tutorials on the use of ADAMS/Durability and ADAMS/Controls.

Tested and updated all the tutorials and much of the online help.

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.

Sample aero property file, AA_sample_aero.aer, has been changed so that the zero pitching moment angle of attack corresponds to a nonzero lift coefficient.

To support the new ADAMS/Aircraft-ADAMS/Controls tutorial, the shared database assembly, AA_Demo_FUL_AircraftControls.asy, has been modified. The assembly now consists of one template, _AA_airframe_controls.tpl, which contains all the control system elements. The template, AA_airframe_controls.sub, has been removed from the shared database. This modified model is more appropriate for use in the new tutorial.

Changed the aircraft.cfg file and the shared database to remove bushing and damper property files based on edm data, which is no longer supported.

The main gear shared database template, _AA_mlg_post_1hub_retract.tpl, was modified to remove redundant constraints.

Wheels/Tires

Tires (user-defined elements, .ACAR.forces.ac_tire and .ACAR.forces.ac_swift_tire) associated with wheel parts in ADAMS/Aircraft changed 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. Further the differential equation associated with the tire's longitudinal slip state is now integrated within the GSE.

When you open a template containing wheel parts and, therefore, tire objects, ADAMS/Car replaces the old tires with the new ones and deletes the differential equation associated with a tire's longitudinal slip that was an input to the tire.

The following templates in the shared database have been updated to use the new tire definition (.ACAR.forces.ac_tire) as discussed above:

• _AA_wheels_main_2by2.tpl
• _AA_wheels_main_2by3.tpl
• _AA_wheels_main_single.tpl
• _AA_wheels_nose_dual.tpl
• _AA_wheel_nose_single.tpl

Mac_int_upd_sta.cmd

Added subsystem-manage and assembly-manage options to the Standard Interface menu by making changes to the macro, mac_int_upd_sta.cmd.

Removed the solver preference option from the Settings menu because ADAMS/Aircraft does not fully support ADAMS/Solver (C++).

38485

Added external files input option for landing gear dynamics gear drop and gear retract simulations. You no longer have to manually enter the data into data tables before running a simulation. This makes these two simulations types more like the other simulations types in ADAMS/Aircraft. The simulation macros and dialog boxes have been updated for this change. Also, the shared database has new example input files for these simulations: retract.gdf and drop.gdf.

44152

The ADAMS/Aircraft customization tutorial provides instructions and example files that, among other things, show how a user can customize the appearance of the New Session dialog box, the Exit Session dialog box and the ADAMS/Aircraft main interface title. Those customizations were inadvertently broken by other coding changes. The files have been repaired and the tutorial has been corrected. Multiple macros were changed in the interface and in the examples/customize subdirectory.

26673

An error, which caused flat link geometry parameterization to hardpoint locations to fail, has been resolved.

41484

The tire model property file provided for the customization tutorial causes erroneous geometry when it is imported as directed in the tutorial. This portion of the tutorial now works correctly.

Items resolved in the 2003 Service Pack and included in the 2005 release:

43479

The shared database example flexible airframe template, _AA_airframe_flexcivil.tpl, referenced a modal neutral file which had a misplaced center of gravity (CG), which caused the aircraft to tip over backwards. The CG has been moved forward of the main landing gear.

42438

Landing gears designed to attach to flexible aircraft through multiple attach points (rather than through a subframe with a single mount part) can now attach properly to the drop test rig. This was achieved through the addition of new communicators to the drop test rig.

To use this new feature, shared database templates were changed through the addition of new matching names to their mount communicators. The old set of matching names allows the templates to merge with the flexible airframe template provided in the shared database. The new matching names allow the templates to attach to the drop test rig. The changed templates are:

• <shared>/templates.tbl/_AA_nlg_post_2hubsflexcivil.tp
• <shared>/templates.tbl/_AA_mlg_1post_2by2flexcivil.tpl

41712

The new measurement request user-defined element (UDE) had incorrect request component labels for the rotational acceleration request option. This has been corrected.

41728

The new measurement request UDE I and J markers could be improperly oriented if you modified the request entity. This problem did not affect measurement requests when they were created, only if they were modified. This has been corrected.

37336, 41013

Made various minor improvements to dialog boxes. The labels were resized so they are completely visible. Also, warning messages were added to the data table Insert Row and Remove Row buttons to make their use more clear.

42622

If you ran an analysis while the tire-mu measure plot window was open, the mu plot window button in the standard interface wheel modify dialog box would no longer function. This has been corrected.

42945

Many dialog box text boxes from which you can select database files had a problem. In particular, when you right-clicked and selected Browse, an error message appeared. Note that the browse function would operate correctly after the error message dialog box was closed. The code has been repaired so that unnecessary error message does not appear.

43469

The road graphic was not positioned properly due to an incorrect reading of request file information when flexible bodies (and thus results files of any type) were present. Also, some request values were reported incorrectly in the post-processor. Note that the simulation and output files were correct, but the graphics and some of the values reported in the postprocessor were not. This has been corrected.

43564

For certain simulation failures that occurred extremely early in a simulation, such that no time dependent data is written to output files, a session crash could occur. This has been corrected.

43661

The new measurement request could be created when you chose it to be of type, single, but not when you chose type, left, or type, right. This has been corrected.