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ppraf

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  1. Hello - Could you please mention the version of Hyperworks you are using? regards praful
  2. Hello Vishrut - Does the full vehicle model run without the flex body ? I would guess you have verified that, but please confirm The error seems to suggest that there is an expression which is using a particular marker, but that marker does not exist in the solver deck. You can do a few things to debug this 1) Search for <Reference_Marker in the XML with the id 21003120. If the marker does not exist, then its a modeling error. 2) For debugging, deactivate that entity which has uses this expression. Does the solver go through? the solution as such may not be meaningful. If it does, then it would mean that, there is a modeling entity that uses a marker but may be removed or deactivated. Let us know how these goes, we can then look further. Regards Praful
  3. Hi Edward - It is not an error but a message from HyperGraph. It can be ignored. Hypergraph has this functionality of associating units to the requests/components. Currently, MotionSolve results is not using this functionality. hence the message is seen. Regards Praful
  4. Hello Edward - Here is how I did it (see attached model). A displacement type motion is used and a sensor is defined to capture the value of the displacement at the needed time. The value of that evaluation is used using the SENVAL statement to modify the motion. In my example, the motion is deactivated initially to let the body fall under gravity, but this is not necessary. The motion can be active if needed. Hope this helps. Regards Praful motion_after_timeT.mdl
  5. Hello Sai It is possible to customize. There are various levels of customization possible. a) Create a wizard library, similar to what is available as the vehicle library under Assembly wizard. You would have to save various sub-assemblies as system definition if there are many and create tasks or events and use the task wizard b) a more complex but one that provides much more flexibility is to customize using the TCL API But to accomplish what you have described above, there is a much simpler way without the need for any customization. Here again there are 2 ways 1) Use the Data Summary to modify the CG, Inertia and Motions. One at a time run the model through the run panel with different names for different set of data 2) You can connect the MotionVIew model to HyperStudy -> define CG, inertia etc. as parameters (design variables), set up a DOE study and submit to Hyperstudy. Hyperstudy will modify the model and solve in loop and provide results for each iteration. I recommend tutorial MV-3000 & MV-3010 to learn about using MotionView in combination of Hyperstudy for DOE and optimization. Regards praful
  6. Hello Sai - Let me answer the questions in a different order 2. What you have shown here is an Action-Reaction force, that means, the force is acting between 2 bodies - 1) referred as an action body (Body 1 in the force panel) and 2) the reaction body (Body 2 on the force panel. The 3 "arrows" in blue are being applied on the action body while the 3 arrows in pink are acting on the reaction body. 3) MotionSolve has functions such as AX(), AY(), AZ() to measure the angle between 2 markers in radians depending upon about which direction the angles need to be measured. From the Expression builder in MotionView, you may click on MotionSolve Functions help to learn more about these functions at https://2020.help.altair.com/2020/hwsolvers/ms/topics/chapter_heads/functions.htm e.g AZ(mrk1_id, mrk2_id) measures the angle about Z between marker with id mrk1_id with respect to marker with id mrk2_id 1) You might have to provide a function such as described above in 3) as an independent variable. MotionView provides some easy means to define rotation between markers that belong to a joint/force/bushing etc.. For e.g if there is a joint with varname j_0, the expression `{j_0.AZ}` would provide the expression AZ() that measures angle between the I marker and J marker of the joint. Note - a) These function return angle in radians. You may use RTOD to convert into degrees. b) Also these functions measures the angle continuously and does not reset to 0 deg after the 360 deg rotation. You would have to wrap this function with a MOD function e.g. `MOD(AZ(mrk1, mrk2)*RTOD, 360)` Hope this helps Regards praful
  7. Hello - I believe you have set up your Activate model, added the MotionSolveSignals block and connected it to other part of the Activate model. You might have to check the Path Preferences from where Activate gets information on which version of MotionView and MotionSolve needs to be used. In Activate - Use the File menu -> Preferences > Path Set the MotionView path to the ~hw_install/hwdesktop/hw/bin/win64 (I am presuming you are using Windows) Set the MotionSolve path to ~hw_install/hwsolvers/motionsolve/bin/win64 Set the MotionSolve license path ~hw_install/hwsolvers/common/bin/win64 The Python path is optional in case the MotionSolve model uses any python user defined subroutines. Regards Praful
  8. Hello Ganesh - You might have obtained the files from https://altairuniversity.com/vehicle-library-user-guide-2/ These files are part of the Baja and Formula SAE libraries. They are definition files that is used to assemble a half car or a full vehicle model. These files cannot be directly opened using "Open Model" or "Import Model" functions. There are training videos that show how these libraries can be used. I would recommend you to go through these materials. Good luck! Regards Praful
  9. Hello charansai Could you please try replacing the file "pathlib.py" at ~install\common\python\python3.5\win64\Lib with the one attached here ? You may rename the original so that you have a back up. where ~install default is C:\Program Files\Altair\2019 for a 2019 install. Regards Praful pathlib.py
  10. Hello - ModelExchange type of FMU is not supported for export from MotionView/MotionSolve currently. regards praful
  11. Hello Narasimhamurthy - Could you please share the version of MotionView you are using and also share the fem file if possible ? regards Praful
  12. Hi forestis - You could use the type "Expression" and have an expression something like this - `STEP(TIME, 1,0,1.1,100)+STEP(TIME,1.1,0,1.2,-100)` In this expression, the first STEP function increases the force to 100 from time 1 sec. until then it is 0. In the next STEP function, the force is being dropped down back to 0.0. (otherwise the force will remain at 100 for the remaining time of the simulation) You may also use a Curve that has the impulse profile of your choice and use TIME as the independent variable while using the type Curve. regards praful
  13. Hello SDB666 - By default, CAD and File graphics are positioned w.r.t Global Frame. You need to parametrize the CAD position with a movable Marker. And that marker has to be defined with respect to the angle parameter that you wish to change. It is doable but not a one click process. I'd be glad to take a look if you can share the model. Another approach would be to create a model with user defined mass properties and for visualization use primitive graphics (and not external graphics). Create a dataset for the angle parameter Create a Marker at the pivot about which the angle is measured. Align the Z axis of the marker along the axis of the pivot. Create points for the graphics using the "Parametric Points" tool using the Marker and cylindrical coordinates 4. Define the body and graphics Modify the angle to position as required. Attached is a sample that I created. points_in_cylindrical_coord.mdl
  14. Hi Laura - Defining revolute in all places will lead to model being over-constrained. That means, overall there are more constraints than the no. of degree of freedom. In reality, are all of these pin joints ? Or are there ball joints too. ? You may chose to work on a combinations of revolute and cylindrical/ball joints to avoid over constraining. Alternatively, you can define joints with compliance. (Turn on "Allow Compliance" check box while adding the joint). Then you'll get the option to toggle the joint from non-compliant to compliant. So then it is not really an idealized joint but a bushing with stiffness and damping property. Provide high stiffness values (1e6 or high) in all directions except Rotational Z. (leave it to zero). Provide some minimal damping (0.1% of stiffness is a good starting value). Regarding the out of plane rotation of 8 deg, you may want to model based on what exactly causes that rotation or what exactly limits the rotation to 8 deg. Is there some kind of a gap/play somewhere?). To begin with, you might want to ignore that out of plane rotation. regards praful
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