Apply a force on a wall

JF's picture
Submitted by JF on Fri, 04/12/2013 - 15:46


I am discovering a very interesting function "mesh/surface/stress/servo" which enables to apply a force on a wall.

fix servo all mesh/surface/stress/servo file plate.stl type 1 com 0. 0. 0. ctrlPV force dim z set_point -10 vel_max 1.

First, I would like to know, what is the parameter 'set_point' in your example ?

Then, I would like to apply a force (10N) on two walls (top and bottom) to perform a compression test in the Z-direction.

#========= Script =============
fix topwall all mesh/surface/stress/servo file topwall.stl type 3 com 0.004 0.004 0.01 ctrlPV force target_val -10 dim z vel_max 1.
fix bottomwall all mesh/surface/stress/servo file bottomwall.stl type 3 com 0.004 0.004 0.00 ctrlPV force target_val 10 dim z vel_max 1.
fix wall all wall/gran/hertz/history mesh n_meshes 2 meshes topwall bottomwall

My problem is the top wall doesn't move and the bottom wall moves away.

Please can you give me some advice to fix this problem.

Thanks in advance.

PS: I have chosen the centre of mass as the center of the wall which is constituted by two triangles