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Stefano1988

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About Stefano1988

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  1. Hi Prakash... I will send you by transfer link my last model...I used two different types of contact: 1 - freeze for the upper side of tach and bucket 2 - slide for the rest contacts (when you will see the model everything will be clearer). The analysis doesn't seem to converge. If you can please check the model... Thanks and regards.
  2. Ok Prakash....but I'd like to be sure about results obtained by non linear analysis....anyway I will attach new results as soon as it will be ready!!!
  3. Ok Prakash I will modify my non linear analysis...to validate the model I could do another analysis in which I could remove the bucket (so there are no more contact zones) and I could apply the load directly on the surfaces representing the contact area....What do you think about it?
  4. Hi Prakash Very well...So I could modify my model to obtain more accurate results, by following your suggestion, in non linear analysis. But what about linear? You talked about spings elements..could they solve the problem?
  5. Hi Prakash At first thanks for your fast reply! When I talk about instability I mean that this kind of analysis has to do some iteration (it isn't static). So if I change, for example, master and slave contacts it doesn't converge. Or if I change the value in discret (from default to s2s) it doesn't converge. So I don't have the full control of the analysis. Then Prakash I attach two different results, obtained by modeling the entire lift group (see model.jpg): 1- The first attempt consists in contact with static friction coefficient and the results are shown in the second picture. Slave contact=tach; master=bucket; non-linear quasi static analysis. 2 - The second attempt consists in a linear analysis with freeze contacts. Same master and slave. The results are completely different. In my opinion the contact model is closer to real situation than the freeze one. But at the same time I am not sure that results of non linear analysis are correct. Thanks and regards. Stefano
  6. Hi everybody. I am designing a rapid attach system for the bucket of a skid steer loader (see picture below), taking inspiration from the commercial systems. In the second picture you can see how this system work: there a contact surface between the bucket and the tach. So there is a contact zone and of sure I should do a non-linear quasi static analysis; however since I would not do a non linear analysis I ask you if there is another way to get a solution. I've already done a non linear analysis but I can't validate the results since this kind of analysis should be quite instable. So I'd like to find another way (with linear analysis) just to compare the results. Thanks in advance for your help Best Regards Stefano
  7. Hi Prakash Ok...I can plot kinetic energy. But what about the impact? May I simulate the impact between a rigid body and a flexible body? I know I can do this in RADIOSS, but MV is far simplier...so I'd like to do this analysis in Motion View. Thanks Best Regards
  8. Hi everybody I'd like to know if it is possible to do an impact analysis in MotionView. For example I'd like to do a FOPS (falling object) simulation on a cab of a earthmoving machine. This test consists in dropping a weight on the top of the cab. I noticed that in MV is possible to assign contacts....so I wonder if it is possible to do this simulation in MotionView (that it is easier than Radioss!!!!). In particular I'd like to obtain (and plot) the deformation energy of the cab's top. Thanks in advance.
  9. Hi Tuki What kind of elements are you using? 3-d or 2-d? For 3-d elements I suggest you to control tet collapse (that should be greater than 0.1).
  10. I try to explain better the purpose of this analysis. I applied 6 constraints (12356 dofs) to the holes which serve for anchoring the arms and the cylinders to the loader frame. Then I applied a load (a pressure) to the bucket surface. So I expected a symmetrical stress distribution. Furthermore my target was to study even the stress distribution on the pins which connect the different elements of lift arm. For this purpose I suddenly thought that I had to apply contacts between the pins and the other components. Now the problem is that the stress distribution on the arms and on the pins is quite different if I use contacts or ties. I applied: 1st case: slide contacts for all surfaces; 2nd case: contacts for internal surfaces and ties for external 3th case: ties for all surfaces By observing results it seems that the third analysis returns the most plausible results.....but it is should be wrong. .
  11. Hi Nguyen-Dai. My name is Stefano and I am working with Antonio to the skid loader project. I will attach you some images about two diferrent analysis: Left side: the analysis were conducted by considering slide contacts between the single parts and the pins Right side: the analysis were conducted by considering contact between one part and the pin and the other part tied to the pin (as you suggest) Now I will show you the Von Mises stresses on the pins, for each analysis: Like before on the left side there are results concerning the first analysis, on the right side the second one. In fact it seems tha pins work better (less Von Mises stresses) in the second configuration. However pins whose connect the lifter cylinder to the bucket are still too stressed. I don't know if I'am doing something wrong.... At last, I attach the last analysis that I ran in which I supposed all TIE interfaces:
  12. Hi JCD The size value just means the dimension of the graphic symbol of the constraint (in model units).
  13. Hi Prakash Thanks for your reply. Of course I know that I can use the online help, but I meant if there were some video tutorial, or maybe some material with examples or models. Best Regards
  14. Hi everybody. Does anyone know if there is a MotionSolve tutorial? I have to do a multibody analysis of a compact loader arm, so I'd like to study a pre-existent arm motion. Thanks in advance.
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