When the orientation of the object changed, how to measure the force on each support point?

Thank you for your interest in my question.

If we assume that there is a box with x, y, z-axis lengths of [1, 0.5, 0.2] (m) , weight is m=100kg,

and set the center point as the origin frame. At this time, if we support the force of m*g/4 at each of the four points [0.5, 0.25, -0.1], [0.5, -0.25, -0.1], [-0.5, -0.25, -0.1], [-0.5, 0.25, -0.1], the object will stay statically.

Then, if the box rotates 30 degrees about the x-axis, I can't measure the force applied at the four corners of the box.

As the box rotates, the coordinate frame of the corner also rotates.

If the box rotates 45 degrees for y-axis after rotating 30 degree for the x-axis,

how should we apply force to each point so that the box stays still?

[Angelo Yeo]

It's always good to share your model. You can use the paperclip icon to share files.

[donghoo]

Thanks for your answer! I shared my .slx file now. Thanks

[Yifeng Tang]

I think there are multiple question here.

(1) how to find the magnitude and direction of the forces needed to balance the brick?

Do you have a way to calculate this? You have 4 supporting points and I believe the solution is NOT unique.

(2) how to apply the force properly?

When applying a force using the external force & torque block, there is an option on Force Resolution Frame. Choosing "World" vs "Attached Frame" can give you very different results.