> The real problem I see is that UniaxialStrainer is modifying positions. So, we agree on most important part.
> It seems UniaxialStrainer should be simply removed (or someone will fix?). I do not have precise ideas on what should be a "strainer" and, if it can be used in discrete mechanics, but maybe other people have, and anyway I have the feeling that this engine is used (at least by 2 people). So, after other points of view, I could fix it, even if I will maybe not use it. It is probably only a matter of setting the velocity corresponding to the change in position. -- Jérôme Duriez Post-Doctorant UJF Laboratoire 3SR Bureau E139 - 04.56.52.86.30 -- You received this bug notification because you are a member of Yade developers, which is subscribed to Yade. https://bugs.launchpad.net/bugs/1300167 Title: (Not) Defining velocities in UniaxialStrainer ? Status in Yet Another Dynamic Engine: New Bug description: Hi, I have the feeling that there is something "wrong" with UniaxialStrainer where the velocities of the "posIds" and "negIds" bodies are not defined, and I illustrate it with following examples (attached) It deals with 2 contacting spheres, with an oblic contact. One sphere is moved towards the 2d sphere, and here both normal and tangential relative displacements occur. - In testUS.py the moving sphere is moved through UniaxialStrainer - Whereas in testUSb.py the movement comes from an initial value of velocity (and NewtonIntegrator) And, obviously, the two simulations are different (see e.g. the plot of fZ sustained by moving sphere). While I would tend to consider these two simulations as identical. What do you think ? To manage notifications about this bug go to: https://bugs.launchpad.net/yade/+bug/1300167/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~yade-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
