Am I doing this right? I get the same Frequency even if I add loads?
Solved! Go to Solution.
Solved by jokiller70. Go to Solution.
Solved by Rafal.Gaweda. Go to Solution.
Could it be I am using 64 bit code?
This is what happens when I issue your code;
Dim robapp As RobotApplication robapp = New RobotApplication Dim cas As RobotSimpleCase Dim rec As RobotLoadRecord Dim ModalParams As RobotModalAnalysisParams Dim ModalCase As RobotSimpleCase Dim I_CN_EXPLOATATION As Integer = 1 Dim I_MARV_FACTOR As Integer = 3 Dim I_MARV_CASE_NUM As Integer = 4 Dim I_MARV_ACTIVATION_DIR As Integer = 6 Dim I_MARV_SIGN As Integer = 7 Dim I_MARV_INPUT_DIR_Z As Integer = 2 Dim I_CAT_DYNAMIC_MODAL As Integer = 11 Dim I_MARV_INPUT_DIR_X As Integer = 0 Dim I_MARV_INPUT_DIR_Y As Integer = 1 Dim I_LRT_MASS_ACTIVATION As Integer = 39 ModalCase = robapp.Project.Structure.Cases.CreateSimple(robapp.Project.Structure.Cases.FreeNumber, "Modal", I_CN_EXPLOATATION _ , IRobotCaseAnalizeType.I_CAT_DYNAMIC_MODAL) ModalParams = ModalCase.GetAnalysisParams ModalParams.DisregardDensity = True ModalCase.SetAnalysisParams(ModalParams) cas = robapp.Project.Structure.Cases.Get(-1) rec = cas.Records.Create(I_LRT_MASS_ACTIVATION) rec.SetValue(I_MARV_FACTOR, 1.2) rec.SetValue(I_MARV_CASE_NUM, 2) rec.SetValue(I_MARV_ACTIVATION_DIR, 2) rec.SetValue(I_MARV_SIGN, -1) rec.SetValue(I_MARV_INPUT_DIR_X, 1) rec.SetValue(I_MARV_INPUT_DIR_Y, 1) rec.SetValue(I_MARV_INPUT_DIR_Z, 1) robapp.Project.CalcEngine.GenerateModel()
video here;
https://screencast.autodesk.com/Main/Details/c3a3df37-81ba-4931-9b71-6e92c12b51e2
Soved it with 32bit code! Robot API also works a lot faster! Autocad nearly same performance. Now to the big question, what is the correct value for self resonant frequency?
you can not convert in some of your models (at least the ones you sent us) case 2
rec.SetValue(I_MARV_CASE_NUM, 2)
because there no loads in it.
So compile your code using "Any CPU" settings
Now to the big question, what is the correct value for self resonant frequency?
All of them are listed in the table you attached to your post.
"Just be careful with how you understand modal analysis. The term "natural" frequency is not applied to every mode. Every mode has a frequency associated with it. That may not be the "natural" one for the structure. If you only get three modes this could be OK for a simple structure, depends on a lot of things. "
I do not know he meant. Ask Tony Ridley.
Robot calculates natural frequencies in Modal analysis.
http://help.autodesk.com/view/RSAPRO/2015/ENU/?guid=GUID-3400C9A4-F47F-4A7F-9B67-66BEE7B9105A