Altair Multibody Solutions 2024 Release Notes

Highlights

The Altair Multibody Solutions 2024 release includes the following enhancements and bug fixes to MotionView and MotionSolve:

Undo & Redo (MotionView)
Frequency Response Analysis (MotionView/MotionSolve)
Experimental – Belt Pulley with Sub-structured flexible bodies (MotionView/MotionSolve)
Experimental – Real time simulations for Vehicle models (MotionSolve)
Dual motor electric powertrain (Vehicle Tools Extension)
Cables Library (Machinery Tools Extension)
Wizard modeling changes (MotionView)

New Features

Undo & Redo (MotionView)

The much-awaited feature to undo (and redo) actions in MotionView is here. Starting this version, it is possible to undo an entity creation, modification, and deletion within a session of MotionView. Use Ctrl+Z to undo and Ctrl+Y for redoing an undone action.

Note: The undo functionality is not available on pop-up dialogs.

Frequency Response Analysis (MotionView/MotionSolve)

The Frequency Response Analysis (FRA) feature has been available in MotionSolve from the previous version. In this version, MotionView offers UI support to set up and execute such an analysis.

A FrequencyInput entity is available to define inputs to the frequence response analysis.

Figure 1.
- The input could be of the following types - Displacement, Velocity, Acceleration or Force.
- The input is in the frequency domain and is provided with an amplitude value, phase angle and direction (DOFs).

The Analysis entity editor supports a new analysis type – FrequencyResponse and Static+FrequencyResponse

Figure 2.

MotionSolve now supports expression based on Frequency using FREQ or OMEGA for magnitude and phase angle while defining the FrequencyInput in frequency response analysis. Example - STEP(FREQ,0.01,1,10,100)-STEP(FREQ,10,0,20,99). Note that this feature is not yet supported in MotionView and will be supported in a future release.

Experimental – Belt Pulley with Sub-structured flexible bodies (MotionView/MotionSolve)

A new belt formulation, called Substructured Flexbodies, is now available as an experimental feature under the Belt Pulley system creation tool. In this formulation, the belt is modeled as a series of linear (CMS) flexible bodies connected by fixed joints. This method offers a faster solution compared to NLFE formulation and with a higher fidelity than discretized rigid bodies formulation.

Experimental – Real time simulation for Vehicle Models (MotionSolve)

MotionSolve now supports real-time simulation for car models created using the MotionView wizard. This functionality can be activated with a simple switch in MotionView, eliminating the need for manual model reduction to achieve real-time performance. Models with flexible bodies, complex geometries, and a large number of degrees of freedom can be simulated in real-time with just a click. In this context, the term "real-time" implies that the ratio of wall time required by the MotionSolve simulation versus specified end time is less than 1. It's important to note that, as this is an experimental feature, not all functionalities in the wizard are supported, and users may experience non-real-time performance or simulation failures. However, these issues will be addressed in future releases. In the meantime, users can disable the real-time feature if needed.

In vehicle models that are built using Car/Small truck library, you can enable the switch by setting the environment variable: HW_MS_REALTIME=1. With this variable set, upon loading/building a vehicle model and adding an event, the following toggle will be visible in the entity editor. Checking this option will export the solver deck with the necessary instructions to MotionSolve to execute real time simulation.

MQTT protocol (MotionSolve)

MotionSolve now supports the MQTT protocol through its msolve API. MQTT, which stands for Message Queuing Telemetry Transport, is an OASIS standard messaging protocol developed for the Internet of Things (IoT). It is designed as a lightweight publish/subscribe messaging transport that enables remote devices to communicate with minimal code footprint and network bandwidth. MQTT has gained widespread adoption across various industries, including automotive, manufacturing, telecommunications, oil and gas, among others. The MQTT support in msolve facilitates bi-directional messaging between a MotionSolve model and other virtual or physical devices via a broker. This capability enables easy broadcasting of signals to groups of devices, making it a valuable feature for IoT applications.

Dual motor electric powertrain (Vehicle Tools Extension)

MotionView adds an option to include a Dual Motor Electric Powertrain (FMU) model in the Car/Small truck vehicle library. This option is available for the “Full vehicle with Driver” and “Four wheel drive” driveline configuration and is accessible under the Powertrain menu of the Assembly Wizard.

The Dual Motor Electric Powertrain is a 1D representation created in Altair TwinActivate and integrated into MotionView as an FMU. It consists of two motors, two inverters, a battery pack, and the vehicle control unit (VCU) responsible for implementing regenerative braking and active torque distribution algorithms.

The powertrain parameters can be modified to accommodate different vehicle models. The input motor characteristic file for the FMU can be generated using Altair Flux.

Enhancements

Entity Editor for Curves

Curve entity now has an Entity Editor alternative to the panel. The editor also has a new “Edit/Show Curve” dialog to visualize the curve and edit it (for Curve of with Data source “Values” only).

Wizard libraries (MotionView)

An Example wizard has been introduced in the wizard library. This library would be useful to learn to create your own wizard library. The Vehicle libraries that came with the standard installation are now part of the Vehicle Tools Extension. This extension can be turned on from the Extension Manager accessible through the File menu > Extensions.

The example wizard offers two simple examples of building a wizard library – Link and Slider Crank. The detailed steps to create a library is also available in the help.

The icons for the Wizard group in the Assembly ribbon have been updated.

Python API updates (MotionView)

Python APIs are now available to register wizard library. The following API commands can be used under mview module to register and set wizard library.


API	Description
getCurrentWizardLibrary()	Gets the current active wizard library
setCurrentWizardLibrary(library_name)	Sets a wizard library as current
registerAssemblyWizardFile(library_name, wizFile)	Registers an assembly wizard file to a library
registerTaskWizardFile(library_name, wizFile)	Registers a task wizard file to a library
registerWizardLibraryDirectory(library_name, libDir)	Registers a wizard library directory
registerMdlStandardIncludeFile(library_name, stdIncFile)	Registers a Standard Include file to be used with a library
registerReportsLogFile(library_name, logFile)	Registers a report log file used with a library

Example:

from hw import mview 
import os
# Register assembly wizard file to the library "My Library"
mview.registerAssemblyWizardFile("My Library", "C:/Libraries/My_Library/assembly.wzd")
# Register task wizard file to the library "My Library"
mview.registerTaskWizardFile("My Library", "C:/Libraries/My_Library/task.wzd")			
# Registers wizard library directory to the library "My Library"
mview.registerWizardLibraryDirectory("My Library", "C:/Libraries/My_Library")			
std_inc = ""
# Get standard include file path from the install location
std_inc = std_inc.join([os.environ["ALTAIR_HOME"],'/hw/mdl/mdllib/std_inc.mdl'])
# Register standard include file to the library "My Library"
mview.registerMdlStandardIncludeFile("My Library", std_inc)
# Register report log file to the library "My Library"
mview.registerReportsLogFile("My Library", "C:/Temp/library_report.log")
# Set “My Library” as the current library
mview.setCurrentWizardLibrary(“My Library”)

Cosin F-Tire version up to 2024-1 (Vehicle Tools Extension)

Altair MotionSolve now supports the updated version of Cosin F-Tire 2024-1 used in vehicle simulations.

Track Builder – Symmetric Track and new outputs (Vehicle Tools Extension)

Increasing the efficiency of the track modeling process, a symmetry option was added in the Vehicle Tools -> Track Builder to automatically create both left and right track systems.

Additionally, track tension output and contact force outputs between the track links and rolling components are now available to simplify the post-processing of the track vehicle results. The soft-soil MDL systems previously added in MotionView model browser when creating a track model with soft-soil as road contact method is now reorganized into a single system containing only the necessary parameters for the soft-soil road model.

Report template for Kinematic and Compliance (KnC) events now available for half-vehicle models (Vehicle Tools Extension)

In the previous releases, a new vehicle Kinematic and Compliance event was introduced in the Entity Browser with a significant workflow improvement on the event parameters. In that version, the automated report was available only for 2-axles, or 4-wheeled vehicles.

In this release, the report template is available for full and half vehicle models created using the car/small truck and heavy truck libraries.

Define length of Soft-Soil road graphics (Vehicle Tools Extension)

A new argument is now available to be used in the soft-soil road files to specify the length of the road graphics from the road reference marker.

LENGTH_START and LENGTH_END define the limit for the graphic created using the road tools. This is independent of the total road length specified in the road file parameters block. As the soft-soil road is symmetrically positioned at road reference marker, this enhancement allows you to remove the part of the road graphics not used during the simulation.

MIN_RADIUS parameter introduced to improve lane change maneuvers for leaning vehicles (Vehicle Tools Extension)

A new attribute “MIN_RADIUS” has been added to the Lane Change and Slalom events for leaning vehicles (Two-wheelers and others). This attribute can be used to specify a minimum radius along the planned path which the control algorithm uses internally to design and fit a spline for the path follower control.

MotionSolve FMU Path (MotionSolve)

While running MotionSolve FMU all paths and environmental variables are now derived from ALTAIR_FMU_ROOT to avoid setting multiple paths.

Extend usage of multiple post user output request with ID (MotionSolve)

MotionSolve now support muliptle post user output requests with ID allowing user to write multiple custom output results in different forms like files, plots and animations.

Changes

Deprecation of Abaqus solver mode: The solver mode ABAQUS stands deprecated from this version and will no longer be supported.
NLFE Spring and NLFE Stabar features discontinued (MotionView): The tools to create a Spring and Stabilizer bar using NLFE have been discontinued.
Multi-disciplinary tools extension (MotionView): The Multi-disciplinary Tools preferences is now available as an extension that can be downloaded from Altair Exchange and added via the Extension Manager.
Export to MotionSolve Python (MotionView): MotionView utilizes MotionSolve's Python API, msolve, to solve models live and optionally offline (non-default). Additionally, user can export a Python solver deck via File > Export > Solver Deck. Previously, there were two distinct styles of writing these Python files. The live run utilized a flat, non-parametric style of solver deck, while the offline run and export utilized a style that preserved the parametric relationship between entities.; In 2024, all methods of generating a Python solver deck have been standardized. Both live and offline versions now generate the flat, non-parametric style of Python solver deck. This change also applies to generating the Python deck in batch mode (using mdl_batch). However, the Optimization Wizard will continue to use the parametric style.; It's important to note that the export of the Python solver deck in parametric style is not currently supported. This feature will be available in a future release.
CAD translator update: The third-party component used in translating various CAD formats except Parasolid (STEP, IGS, CATIA etc.) has been upgraded to a newer version. This upgrade addresses issues with slower CAD reading and poor geometry translations seen previously.; A side effect of this change is that names of some components may appear changed in certain scenarios causing an error during loading of legacy models. The components can be reselected using the entity editor of Graphics entity in such cases.
Static Load analysis in Entity Browser (Vehicle Tools Extension): The Static Load analysis for the half-vehicle models created using the Car/Small truck and Heavy truck libraries is now included in the Entity Browser under Vehicle Tools > Events > General.; The analysis can be used to study the effect of various loads applied at the wheel center and tire patch. This enhancement presents the analysis parameters in the Entity Editor, simplifying the workflow to add and edit the events.
Tire Envelope analysis in the Entity Browser (Vehicle Tools Extension): The Tire Envelope analysis for the half-vehicle models created using the Car/Small truck and Heavy truck libraries is now included in the Entity Browser under Vehicle Tools > Events > General.; Designed for packaging studies, the Tire Envelope analysis exercises the suspension to the extremes of ride and steering travel to verify the interference between the tire and the suspension components or vehicle chassis. This enhancement also presents the analysis parameters in the Entity Editor, simplifying the workflow to add and edit the events.; Figure 12.
Complete workflow for half- and full- vehicle analysis (Vehicle Tools Extension): With the Static Load and Tire Envelope analysis moving to the entity browser with parameters editable in the entity editor, the support for the Analysis Task Wizard is being removed in this release.; This enhancement completes the vehicle modeling workflows in a concise and simple way. To build a vehicle in MotionView, three steps are now required: 1) Select the vehicle library using the Libraries ribbon option, 2) Build the vehicle model using the Assembly option and 3) Add an event from the Entity Browser accessing either the MotionView option View->Entity Browser, or from the Events ribbon button that automatically opens the entity browser.; Figure 13.
Changes in CAD/FE Import using HyperMesh: The Utility menu in HyperMesh that appears while importing CAD/FE using HyperMesh in the interactive mode has been migrated to a MVUtils ribbon.; Figure 14.
Organized binaries (MotionSolve): Organized verticals and tire related binaries under msauto folder to avoid conflicts from 3rd party binaries.

Extensions

Cables Library (Machinery Tools Extension): The Machinery Tools extension version 2.0 is now available in the Altair Community > Altair Exchange > Extensions. In addition to bearings and gear libraries available in the version 1.0, this version adds the cables library.; The cables library enables modeling and simulation of winches, pulleys, anchors and cables wrapped in various configurations. The formulation supports cable preload, parametric pulleys profile with sliding contact and disengagement, and different wrapping modes such as anchor to anchor, winch to anchor through pulleys, anchor to winch through pulleys, and winch to winch through pulleys.; When loaded in MotionView, the extension appears as MotionView page containing a ribbon with icons for all available components. It also loads the component library folder in the entity browser which can be accessed by clicking on the ribbon icons. Three new examples are included in the extension to demonstrate the cables’ capabilities as shown in the figure below.; Figure 15.

Resolved Issues

Analysis end time in Entity Editor does not get reset to default after performing File>New.
Segmentation error when creating system after creation of other entities and use of model wizard.
Solver_Filename and Solver_File_basename datamembers are not set when solver deck is exported/run using Python
Solver_Filename and Solver_File_basename datamembers are not set correctly when Template is pre-evaluated during export of solver deck.
An app error is encountered while saving external definition based Analysis
Double clicking on rigid group does not bring up its edit context
CreateBlankModel TCL command crashes MotionView
MarkerPair and BushingPair entity editor does now show Orientation information after switching sides.
System attachment of type Dataset cannot be resolved using Advanced selection dialog in the Entity Editor.
Resolving marker collectorin guidebar to an attachment's attribute sets it to the marker resolved and not as attachment’s attribute.
Point coordinates are modified when orienting a marker that refers to the point for its orientation.
Node tolerance information for the flexbody input in the Nodes & Modes dialog is not saved.
Component names with backslash and spaces are not handled correctly during export to solver.
Curve created using the “Create line from points” does not maintain its parametric relation with the points.
User expression is not displayed in compliant joint and bushing entity editor.
Static hold option in FMU entity editor gets reset after change.
Model tree in the FMU Export dialog appears empty after loading Vehicle Tools extension.
Solver Array editor Plant Input/Output shows solver variable button with wrong default count.
App error in python window when changing node tolerance in Flexbody Nodes & Modes dialog.
Curve extracted using faces is not to proper scale.
Asymmetric bush pair on one side displays curve that is selected on the other side.
"Run Offline" cannot be changed from Run Motion Analysis dialog box if user has set it in File>Preferences.
Action only Guidebar in Forces context is not restored when the “Action only” checkbox is turned off and on
Changing the variable name of a NLFE sets the entity properties back to default values
Local file widget in User Defined properties fails to accept string as an input for the dll name
MotionView crashes on live run when body refers to a non-existent point as CG
Expression using getnodecoordinates is not evaluated when model is loaded or when flexbody is updated.
Shortcut key Ctrl+E for Export solver deck does not work.
Incorrect unit text in entity editor fields when using centimeter as length unit.
MotionView crashes when adding FMU generated from SmartUQ.
hide_in_post for Outline graphics does not work.
User Defined Template is not executed during live run or offline run with Python.
Live run does not create .meta file when model contains force outputs on bodies.
Box graphics orientations are sent incorrectly to msolve Python
Damper graphics are not sent to solver.
Model containing NLFE does not run.
Loading a model with flexbodies referencing to previous results may cause a crash
Vehicle model with N-post event fails to run Live
Runs in different folders appear under different tree under Run History
Rerun of models with changed end time shows incorrect animation in Results Review
Points at interface nodes are not created under the parent system of the flex body
Making Point designable causes MotionView to crash
Two-wheeler Lane Change events fail when the lane parameters are resulting in very tight turns for considerable velocities.
KnC and n-Post events Jacks are not detecting the tire radii properly to place the posts at the contact patch.
Suspension models containing dual tires were not properly supported by the n-post vehicle events. Dual tires were replaced by a single tire.
Initial spike in acceleration signals for models that employ Siemens tires with USE_MODE = 514/534.
During EDEM Co-simulation, the force calculation for rigid bodies were done similar to flexible bodies based on forces on each triangles, which impacted the performance on rigid models. With latest MotionSolve the forces from EDEM is calculated for the entire geometry for rigid bodies since they don't deform.
Removed EDEM2H3d converter since HyperView natively supports reading EDEM models and results.
Fixed the missing data which are not saved to xml while using save_increment
Fixed issue related to MotionSolve-EDEM Co-simualtion, where MotionSolve was not responding for models containing flexible bodies with delayed start Co-simualtion (when the co-simulation start time > 0).