General Mechanical

General Mechanical

Error : state inconsistency, no relevant contact point for an active/impacting contact pair

    • MOrdiz
      Subscriber
      Hi to all,nFisrt of all, thank you for taking time to read this question.nI'm trying to simulate a gear crank mechanism with a radial gap in one of the joints. I'm using a rigid Dynamics Transient. I wanna obtain the stress of the follower so I made a condensed part with it. I prepare the simulation, add a little movement of 10 degrees in 0.1 seconds, no force, an easy essay. But it returns the error shown in the title. I can do it adding contacts in a Transient, but it takes 5 hours to resolve the contact, so I try this option to add some speed.nCurrent Time: 0.0001732 s Current time step 1.17452e-06 snRadial Gap Stop on Joint Radial Gap - Multiple To Prensa\prensa2 is open. Current Radii 0.000680701 0.0012995 Bound 120.05nError : state inconsistency, no relevant contact point for an active/impacting contact pair. Try reducing the time stepnState Inconsistency for the contact: Shock detected without contact pointnState inconsistency at time 1.731665e-04. The solution has been restarted.nnI try to reduce time steps minimun to 1e-10 but it crashed. Don't know what to do.n
    • MOrdiz
      Subscriber
      Also appear this:nCurrent Time: 0.000173 s Current time step 2.40422e-06 snRadial Gap Stop on Joint Radial Gap - Multiple To Prensa\prensa2 is open. Current Radii 1.75442e-09 0.000873881 Bound 120.05nInconsistency Inactive PenetratednState inconsistency at time 1.730103e-04. The solution has been restarted.n
    • peteroznewman
      Subscriber
      nThe normal approach takes 5 hours. You tried and failed to make a shortcut. Use the 5 hour method.n
    • MOrdiz
      Subscriber
      nFirst thank for your reply,nThe problem is that I need a faster model for iterative application. nThe main problem is that I don't need to know about the contact, I only need to know how the impact affects the stresses of the structure.nThat's why I want to eliminate the contact analysis to only obtain the stress result.n
    • peteroznewman
      Subscriber
      nThe impact forces are computed by the contact algorithm. If you know what the impact forces are, you don't need contact.nIn some simple impact conditions, such as a rigid body impacting a flexible body with a known velocity (such as a drop test), I can replace contact with the peak elastic deformation calculated based on conservation of energy principles. Kinetic Energy = 1/2*M*V^2 = Strain Energy = 1/2*K*X^2. Push on the impact point in Static Structural to compute K, then solve for X, which is the peak deformation to absorb all the Kinetic Energy. You can look at the stress in a Static Structural analysis when it is deformed by X.n
Viewing 4 reply threads
  • You must be logged in to reply to this topic.