How to move a rigid body by applying force on its reference point?

[ab110]

Hi,

I want to do an Abaqus static standard analysis. In this analysis I should move a rigid body by applying force on its reference point. When I apply this force the analysis does not run and I get the message “too many attempts” in the first increment. I have changed the parameters of step but it does not work. I attached a simple example. In this example I wish to move the rigid body by applying the force and have contact between this rigid body and the sheet. Please consider if I move the rigid body by displacement the analysis runs and there are not any problems. The problem is about applyind the force.

Cheers,
A,

 

[Drej]

You may be getting rigid body motion and therefore you should try applying a displacement to the reference node. From this you can obtain reaction forces and apply if you need to. Apply the displacement in two steps: the first step just to initially make contact and the second to apply the full load. If you absolutely need to apply a force then consider using very weak stiffness springs attached to the body to avoid the rigid body motion.


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[fruton]

I always apply forces to rigid body reference points without any problems? Am I missing something? Is there a problem with applying it as a force in terms of the results accuracy?

 

[corus]

As Drej says, apply 2 steps, the 1st with displacement only. This will set up contact forces. In the 2nd step remove the fixed displacements and replace by your force. Now you have contact forces set up between bodies then you shouldn't get rigid body motion.

Tara

 

[ab110]

Thanks everyone for your help.

@Fruton: you can check the attached file. by applying force on rigid body, the analysis does not continue because of rigid body motion.