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## Popular Content

Showing most liked content since 03/06/20 in all areas

1. 3 likes

## 3d to 3d contact- parameters

There is not a simple answer to your question. The general guidance is to reduce penetration between components as much as is reasonable, without making the stiffness so high that is results in computation difficulties. Sometimes you need to try different types of normal force calculation, sometimes it's the parameters themselves. In our help section, please read careful the section on Best practices for 3D contacts. Your wheel geometry does not have a uniform mesh, which is important for accurate contact forces. Just search the help for "Best Practices for Running 3D Contact Models in MotionSolve". There is a lot of important material there, that will save you a lot of time and headache if you will follows those best practices in setting up your problem.
2. 1 like

## my simulation is slow

If you request S-parameters, Feko will automatically load each port with 50 Ohm (or a different value if the user specifies it). You have added 50 Ohm loads manually - effectively you are calculating S-parameters in a 100 Ohm system.
3. 1 like

## Car Windshiled Wiper system MBD simulation

So, we have an existing solution today using MotionView, and customers are using it today. I would recommend you sign up for one of our MotionView training classes, and that will equip you with the necessary knowledge to complete this kind of simulation successfully.
4. 1 like

## Output: Write Results to Tabular File

Hi Tim, I was looking for the same thing. Unfortunately, I didn't find a 'smart' solution to do it. I pass by HyperView ... Please let me know if you find something. Cheers,
5. 1 like

## Practice STEP for Solid Welded Block

For new users, here's a simple STEP assembly of a solid welded block, with a round bar the user can attached as desired. With just four bodies, this assembly is a good way to practice and add to your skills. They are simple enough to try different techniques joining the bodies, or even b oolean. Here's an image on my practice model. The loop weld is joined to the base, block joined to the weld, and solid rod joined by MPC connection. The block is not joined by mesh to the base, as in the real welded part. The resulting stresses are shown for the same h3d file, for 2019.3 (left) and 2019.2 (right). There appears to be some difference in how the stresses are displayed for the two versions, but the queried stress is the same. Enjoy, and share and teach your newbies. Darryl TEST_SOLID_WELDED_BLOCK.stp
6. 1 like

## my simulation is slow

Please share some details about what you are trying to solve.
7. 1 like

## my simulation is slow

That looks like an out-of-core solution which uses the hard drive as "memory". This can be very slow. You will need to use a machine with 200 GByte RAM or more, or reduce the number of mesh elements of the model, or consider a different solver.
8. 1 like

## Error: [fmi2GetContinuousStates]: Simulation terminated at t=0.0000000000000000e+00: error running events

Hi Arbigaber, It's a problem of initial values. In Modelica mechanics length of elements in a row are added. with basic parameters, the initial position of v-source is 0 m, length of left rod 0,4 m. Position of fixed is 0 m => relative stroke of cylinder is 0,4 m (in right end stop). Now you have to move either v-source to the left or fixed to the right to move piston into middle of the cylinder. My demo model has a fixed position of 0,2 m. InitialValues.scm
9. 1 like

## apply a load to hollow part

Glad to help. You need to split the geometry into design & non-design components using geometry>solid edit>trim with nodes, lines or plane/surf. Solid_Edit_Panel.pdf
10. 1 like

## How to create a big displacement model for membranes

This error is due to non-convergence (check the out file for details). Increase the number of cutbacks allowed (NCUTS) in the load collector with NLADAPT card image and refer this load collector under NLADAPT subcase definition (loadstep). However, there is a limit when implicit methods become computationally inefficient (buckling, wrinkling, unconstrained rigid body motion, large deformation, rupture, contact with friction,...). These cases can be solved by the explicit method. 30Diametro-edit2.hm
11. 1 like

## Getting material data by id

Hello @vreddy @timonq Whatever the solver profile, manually change the material data value in hypermesh, and read the command.tcl file. Suppose you have changed the density (rho), you will notice the following reflected in your command file: (hypermesh 2017. In older versions, you can find it in "attributeupdatedouble") *setvalue mats id=41 STATUS=2 183={8.77e-009} which means "183" is the parameter code. Since you have the attribute dataname now, you can query it in your script like so: hm_getvalue mats id=41 dataname=183 This will return the rho (density) value currently assigned to the field!
12. 1 like

## How to generate a combined data for near and far field for multiple configuration

There are some options: 1. Use application automation in POSTFEKO to postprocess/plot all the data from all the results files. This means that you would have to learn to write an automation script. The User Manual and example guide have more info. 2. Create one CADFEKO model with all 16 files’ angles. This would mean 16x16=256 configurations. You don’t have to create each configuration one by one. Just enable script recording, create a few configurations, and then modify the recorded script to use e.g a FOR loop over all the angles. The angles could be read from file. Lua resources are freely available on the web. 3. Modify your existing CADFEKO model files to output the fields to ASCII file – see Advanced tab of far fields and near fields. You will have to rerun all the models, but it should be quick if the *.str files are available. There will be multiple *.ffe files (Far fields) and *.efe/*.hfe files (near fields) corresponding to the configuration numbers. You will need to append all the files into a single *.ffe/*.hfe/*.efe file. This could be done with a script. Then use the Import function of POSTFEKO to import the combined data file.
13. 1 like

## How to plot energy curve of impact analysis in SL?

Hello Alpha After running Radioss analysis you can plot the energy curves from the results in SimLab using the Plot tool from Results > Results > XY Plot. Please follow the steps as follows using the XY Plot tool 1. Set the Data type as Loadcase/Frequency. 2. For X data select the Loadcase button. From the Loadcases sub dialog select the time steps of your choice. 3. For Y data select the results component as Specific Energy. 4. Select the nodes for which you want to plot the energy curve from the model and click plot. The energy curves are plotted for the selected nodes from the model in differentiating colors. Kindly let us know if you face any difficulties. Thanks & Regards Nantha Kumar N
14. 1 like

15. 1 like

## How to create a big displacement model for membranes

Glad to help. I suggest you go through free Altair e-books and start with Practical Aspects of Finite Element Simulation. You can also learn from learning and Certification program: https://certification.altairuniversity.com/ > (Learn Modeling and Visualisation)﻿ Check the following youtube channels: AltairUniversity Altair India Student Contest ELEATION By Apoorv Bapat﻿ If you are new to FEA I recommend Finite Element Analysis For Design Engineers by Paul M. Kurowski: https://www.sae.org/images/books/toc_pdfs/R449.pdf
16. 1 like

## Skew modeled solids / Interference Problems

You are welcome. Do not worry. We are here to help. Have a nice day.
17. 1 like

## Private message

The objective of the forum is to have public technical discussions for the benefit of all users, private messaging is hence disabled.
18. 1 like

## How to quickly import material from OS or Radioss to Simlab

Thanks Kamalraj! I got it.
19. 1 like

## Roller bench test for motorcycle

Hello, In continuation to Chris's response, attached is an example MDL file created in HW2019.1. You need to browse the tire and road property files again before solving. Refer to the MF-Tyre documentation for more details. Hope this helps in setting up your model. Thanks. Model_DrumRoad.mdl TNO_car205_60R15.tir TNO_DrumRoad.rdf
20. 1 like

## Simulate Robot Arm by using Activate

Have you watched the Arduino Series at Altair Embed website? It is a good source of information to start with: https://solidthinking.com/resource/9673/?weight=2 Regards, Roberta
21. 1 like

## Quality Index For 3D-elems

Hi Alex, I think you are looking for this:- F10 >> 3D Have a look at the image below.
22. 1 like

## Add a port for imported mesh

Hi Cris Yes, this is possible in CADFEKO. All (geometry) ports in Feko also have equivalent "mesh port" representations and you should be able to define these on your imported mesh. For example, if you have both geometry and an imported mesh in your CADFEKO model, and you select the option to create an "Edge port", CADFEKO would ask you if you want to create a "geometry port" or a "mesh port". If you only have an imported mesh, CADFEKO would open the mesh port creation dialog when selecting to create a port. One point to note is that the port creation requires mesh elements to be defined in the required labels. For example, to create an edge port on a mesh, you would have to have the mesh elements grouped into at least two "faces": one for the positive face of the port and one for the negative face. If you could provide more detail on your mesh and the type of port you are trying to create, we might be able to provide more detailed suggestions. Kind regards, Johan H
23. 1 like

## Card image carbon fiber (Ls-Dyna)

Hi, The following lines from the attached documents will favour the usage of M54_55 material card. The LS-DYNA MAT54 material model is of interest for large full-scale structural damage simulations because it is a relatively simple material model which requires minimal input parameters. Not only does this reduce the computational requirement of a MAT54 simulation, it also reduces the difficulty and amount of material testing necessary for input parameters. Material 54 uses Chang matrix failure criterion (as Material 22), and material 55 uses the Tsay-Wu criterion for matrix failure. paper-feraboli.pdf open this one crash_feraboli_JAMS May 2011h.pdf
24. 1 like

## Loop area when a conductor in finite element space is closed with circuit element

Hi, You are welcome. I managed to create a python script allows to create the new mesh coil. The aim is to show how to create a non-meshed coil. you can also configure it by creating geometric parameters. You will find attached the python script. Best regards. Create_Non_meshed_coil_Flux_2018.py
25. 1 like

## Motion Analysis

There is no specific tutorial for this. You can find the details about our Belt-Pulley tool in our MotionView help: Altair MotionView -> MotionView Panels -> MotionView Toolbars -> Subsystems Toolbar -> Create a Belt-Pulley Subsytem Further questions should be directed to our Multi-body dynamics forum. Note that modeling belt-pulley systems is rather challenging and can be computationally expensive.
26. 1 like

## Isolate elements/components

I think: Isolate a comp means display that comp and let remained comps off Isolate Only a comp means display that comp and let remained comps and other entities (loads, group,...) off
27. 1 like

## Loop area when a conductor in finite element space is closed with circuit element

Yes , I used Flux 2019.1.1 to create the non meshed coil. can you update you Flux? best regards.
28. 1 like

## Deleting overlapping lines

Yes i have I will select the lines, create temp nodes on them, delete them, then regenerate an unique line from the nodes. We don't need script for this.
29. 1 like

## show several subcases in one window

Hello, you can split a page into several windows by using the following button in HyperView You can display in every window different subcases / models / ... Best regards Tommy
30. 1 like

## Querying Assemblies and Components in Linux

Here's my test to get ID list of all comps: > ./cmd2.sh 21 22 23 24 31 32 33 34 35 36 37 38 3 4 1 2 5 39 42 44 46 47 File cmd2.sh: #!/bin/bash HM="/opt/hw/2019.1/altair/scripts/hm" OPTS="-nocommand -nouserprofiledialog -batch -nobg" TCL="-tcl test2.tcl" export ALTAIR_LICENSE_PATH="6200@YOUR-LICENSE-SERVER" \$HM \$OPTS \$TCL 2>/dev/null FIle test2.tcl: *templatefileset "/opt/hw/2019.1/altair/templates/feoutput/nastran/general" *readfile "/FULL/PATH/samcef_validation_hw2019.hm" *createmark comps 1 "all" set comp_list [hm_getmark comps 1] puts "\$comp_list" HTH,
31. 1 like

## Simlab always Delete all BC & Constraints when create new solutions

Hi Darad, This is pros & cons. I also feel the same like you when start to use SOLUTIONS browser. I think Solutions Browser is easier for new users. Secondly, it sounds SL want to do more (thermal, cfd, EM), rather than only mechanical. Then Load & Constraints may be conflicted and difficult to do automation. Now I am learning python script and found this may be useful.
32. 1 like

## How can I delete duplicate lines?

You don't need to delete it because finally you export mesh, not cad.
33. 1 like

## Solids vertices change at the time of splitting with surfaces or planes

Yes, I have got the same issue for some time. Here're my tries: Check the geometrical tolerance (pres O) Try to isolate the volume which causes the issue by splitting solids Try to work with surfaces instead of solid
34. 1 like

## PMSM simple speed control

Hello andyer, Thank you very much for the info!! Really helpful and I appreciate it. In the mean time I developed two models my self that they seem to work. I am attaching them. If you have any suggestions recommendations fell free to tell. Kind regards,PMSM_FOC_SVPWM_torque.scmPMSM_FOC_SVPWM_rpm.scm Christoforos
35. 1 like

## RBE3 elements and boundary conditions

Hello JJJ You can connect the supports in the chassis to the defined node using RBE from Analysis > Loads & Constraints > Connectors > Manual RBE For restricting the DOF's of the Independent node of the created RBE's, apply Property from Analysis > Property. Select the RBE's from the Model browser. Set the Entity as RigidBar & Type as Rbe2. Set the DOF of the Independent node in the DOF tab. Kindly let us know if you have any doubts. Note: I have already replied to your query in the following link Thanks & Regards Nantha Kumar N
36. 1 like

## Which theory is used to solve in Optistruct with PCOMPP

OptiStruct uses classical lamination theory to calculate effective stiffness and mass density of the composite shell. This is done automatically within the code using the properties of individual plies. The composite inter-laminar stress is calculated based on the first-order shear deformation laminated plate theory.
37. 1 like

## Symbolic function

Hi Ivan, Unfortunately oml language doesn't support yet symbolic math. You can try to leverage Python-bridges provided by Compose though. Cheers, Lorenzo
38. 1 like

## Flux-MATLAB/Simulink Cosimulation Failed at the beginning

Hello Aravind, I think the problem is that you have indicated as directory C:\Program Files\MATLAB\R2018a\bin, it should be C:\Program Files\MATLAB\R2018a, instead. Try this, I think it is going to work. Best regards, Alejandro
39. 1 like

## RADIOSS BLAST SIMULATION

Hi, according to Radioss help this value should be calculated:
40. 1 like

## ESL w Radioss

Hi, Radioss optimization requires an additional runname.radopt file containing the optimization keywords. This file has to be created manually with any text editor taking care to follow the appropriate syntax. It is also possible to setup the optimization problem in HM (Optimization View in Model browser) but I haven't found a way to export/run the radopt solverdeck. Attached are two examples from Radioss help 51_RADIOSS_Optimization.rar Implementation.pdf RD-E_ 5101 Size Optimization of a B-Pillar.pdf RD-E_ 5102 Topology Optimization for Solids.pdf
41. 1 like

## Simlab 2019.2 issues

Hello Darad Please find my comments regarding your concerns in SimLab 2019.2 as follows 1. For results display, the Contour and Displacement icons for Results ribbon have disappeared In SimLab 2019.2 version the Contour icon, Displacement icon, Animation toolbar have been removed and modified and placed at the bottom of the GUI. Please refer the below demo video on Animation panel 2. Upon importing an existing *.fem, all Analysis ribbon icons have disappeared as well as Loads and Boundary conditions tab in browser window. Yet, if I export the *.fem from the session, one can still Data Check and Solve the model. More enhancements were added to SimLab 2019.2 version. One of them was to create Solutions during import of *.fem files inside SimLab. If we enable the toggle "Create Solution" a solution will be created based on the imported *.fem file in the solution browser and the Loads & Constraints will be added in the solution browser only. The Analysis ribbon & Loads and Boundary Conditions displayed will be related to the type of solution that is created. If you disable the toggle "Create Solution" and import the *.fem file it will be imported likewise in SimLab 2019.1. Thanks & Regards
42. 1 like

## Open a *.pdf file using tcl script

Hi Try this exec "C:/Program Files/Internet Explorer/iexplore.exe" "C:/Users/Nyaaa/Desktop/test.pdf"
43. 1 like

## Car Windshiled Wiper system MBD simulation

The model provided then is too simple for what you want to achieve. For a wiper mechanism, you typically will use MotionView, rather than InspireMotion, due to the need for flexbodies of the support structure, among other features. Also, I find it useful to model the wiper blades using polybeams, and then simple contacts between the polybeam and glass. There is a "snow blocking" test that needs to be set up and run on the wiper. Scripted simulation is helpful to set up the model here. Again, this is a feature currently found only in MotionView. Unfortunately, I don't have any models I can share, due to customer confidentiality.
44. 1 like

## random wires

You could try a for loop of a modified macro-recording of creating a wire in CADFEKO. Look at the math.random and math.randomseed functions.
45. 1 like

## Automatic meshing: BatchMesher fillets

Yes, it just indicates "minimum" element row, so if the fillet is wider, BM will mesh it with more rows Which number of row do you want to fix?
46. 1 like

## How to do a parameter sweep in activate?

Let me add another approach that I've just learned. There are many options to perform it but I’ve found this method very simple, flexible and self-explanatory. Summary: In the example, watertank.oml is the master file. It: changes the input parameters (controller gains) runs (repeatedly) the file Watertank_parm.scm (slave) collects results doing post-processing (plot) at the end. I’ve created a quick video to summarize how to run the demo. Present working directory must be where you save the files (the video shows how to select the pwd). Otherwise use an absolute path in the oml file. Liv ParameterSweeping.mp4 watertank.oml watertank_param.scm
47. 1 like

## FAQ コーナー 2019.1, 2019.2

質問: ランダムに短繊維を混ぜたときの特性は 回答: 2019.1 から、ランダム繊維のユニットセルがサポート外になりました。その代わり、一本の短繊維の特性と、繊維配向テンソルを使って、特性を算出できます。 このように短繊維ユニットセルを作り、 このように、繊維配向を設定します。 このように、材料特性が算出されます。
48. 1 like

## TCL TO GET MIDLINE

Panel geom>lines>mid lines Does it help?
49. 1 like

## FMIの計算がうまくいかない場合は

FMI (Functional Mock-up Interface)を用いれば異なるソフトウェア間の連携が可能ですが、計算が流れない等の問題が生じた場合は、どちらのソフトに問題があるのか原因を特定するのが大変です。 そんな時のために、FMIのOfficialページにて、FMU Compliance Chekerというツールが配布されています。このツールを用いますと、FMU単独で計算実行できますので、まずは、FMUのエクスポート側に問題がないかを確認することができます。 今回、Altair Activateから出力したFMUに対して、このチェックツールを適用してみました。無事に単独で計算が流れ、このFMUには問題がないことが確認できました。 CSVファイルで入力も作成できますので、入力に対する応答もチェック可能です。 FMIの計算でお困りの場合は、是非、このチェックツールを使ってみてください。 FMI Official : https://fmi-standard.org/ 1DシミュレーションツールAltair Activate : http://solidthinking.jp/product/activate/ fmu_checker.zip ※ファイルのダウンロードには、必ず当フォーラムへのログインが必要となります。ログインしない状態でファイルをダウンロードすると、ファイルが存在しないといった旨のメッセージが表示されますが、実際にはログインするとダウンロードが可能になります。 activate_fmi_check.mp4
50. 1 like