Add force (vary with time) onto a moving body

Yage · November 9, 2015, 13:24

Dear Forumers,

I would like know how to generate a force vary with time. I would like to add it into 6DoFmotion solver, to allow a submerged body accelerate for then fully stop in the end.

Is there any example or any similar code to study.

Regards,
Yage

hk318i · November 10, 2015, 13:46

I believe your question is not clear enough. Because your question is self contradicting. The 6Dof motion is mainly solving the equation of motion based on the flow forces acting on immersed body. On the other hand, as I understand from your question, you wand to prescribe the motion. Is that true?

Yage · November 10, 2015, 14:00

Quote:

Originally Posted by hk318i

I believe your question is not clear enough. Because your question is self contradicting. The 6Dof motion is mainly solving the equation of motion based on the flow forces acting on immersed body. On the other hand, as I understand from your question, you wand to prescribe the motion. Is that true?

Hi,

Sorry for the unclear question.

I would like to move the rigid body by a continuous force, like a paddle in water.

1. I found there is a "sixDoFRigidBodyMotionRestraint" function in "sixDoFRigidBodyMotion" and it can restrain the rigid body by a linear force, which vary with the rigid body position, I would like to know if I can do something based on that.
2. or a customized boundary condition?

Regards,
Yage

hk318i · November 10, 2015, 15:33

Hi,

I believe you mean the linear spring restrain, generally restraints represents springs that is why they are function of position. But in this case the flow forces are integrated every time step and will effect the body motion, therefore obtaining a certain movement is not easy task. It is interaction problem.

November 9, 2015, 13:24	Add force (vary with time) onto a moving body	#1
Yage Member Yage Join Date: May 2014 Posts: 60 Rep Power: 12	Dear Forumers, I would like know how to generate a force vary with time. I would like to add it into 6DoFmotion solver, to allow a submerged body accelerate for then fully stop in the end. Is there any example or any similar code to study. Regards, Yage Last edited by Yage; November 9, 2015 at 14:59.

November 10, 2015, 15:33		#4
hk318i Senior Member Hassan Kassem Join Date: May 2010 Location: Germany Posts: 242 Rep Power: 18	Hi, I believe you mean the linear spring restrain, generally restraints represents springs that is why they are function of position. But in this case the flow forces are integrated every time step and will effect the body motion, therefore obtaining a certain movement is not easy task. It is interaction problem. __________________ @HIKassem \| HassanKassem.me

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November 10, 2015, 13:46		#2
hk318i Senior Member Hassan Kassem Join Date: May 2010 Location: Germany Posts: 242 Rep Power: 18	I believe your question is not clear enough. Because your question is self contradicting. The 6Dof motion is mainly solving the equation of motion based on the flow forces acting on immersed body. On the other hand, as I understand from your question, you wand to prescribe the motion. Is that true?