Abdominal Pressure

Main Forum
1

Hello,

I am currently learning Anybody system. I understand that the abdominal pressure is idealized as a cylinder and how it works to change the volume. I check many codes, but I am still confused about how the force produced by volume is applied on the lumbar spine? How the contact surface between the spine and cylinder is determined and what is the value?

Thank you very much!

2

Hi Amin,

Please have a look here starting from page 14 and onwards:
Wiki-article on the IAP

Kind regards,
Pavel

3

Hello Pavel,

I am not sure the link is the same as the following.
https://github.com/AnyBody/support/wiki/AnyBody-Body-Model

I read the information about IAP and all threads regarding IAP in forum. The last sentence from the website “using geometric/anatomic estimates of pressure surface area and area centroids, which in turn determines the effective moment arm of the pressure.”
I have two questions for this sentence.

  1. Only moment produced by IAP no shear force. Correct? I also put forward the same question in the other thread.
  2. The area is based on the cylinder or the area of thorax and the pelvic floor? And I want to know where to find the area.

Cheers,

Amin

4

Hi Amin,

Sorry for the late reply.

Here is the link to the IAP description (now working).

  1. No, the way it is implemented it will not result in shear forces.
  2. It looks that, it is uses estimates for the areas as it is implemented right now. You can find the code in Buckle.any (double-click on the grey ellipsoid and navigate to the code from the model tree).

Kind regards,
Pavel