Can you measure stress in Simscape Multibody?

Hi,

Just a quick question relating to Simscape Multibody out of interest. Having looked on-line and through the manual and not finding any method documented, I wondered if anyone has managed to come up with a way of measuring dynamic stress within a model. Certainly there is provision for measuring different forces in and around the model and the area is know of the component - as stress is equal to force / area in the basic sense (I'm not a Mechanical engineer), why is there not a function for calculating stress? I noticed that there is a strain gauge in Simscape Electrical, can this be employed within Multibody?

Obviously, the measurement will not be like a FEA model, but it would be interesting to know if it is possible or anyone has got round the problem?

Kind regards,

Andy

[Andy Wileman]

As a follow up to this question, I was wondering given that forces can be measured through the model, can Dirlik's method be used to give a measurement of stress in a model?

Answer 1

[Steve Miller]

Simscape Multibody models calculate the quantities necessary to determine the stress in the beam. While the beam models do not output stress quantities directly, you can use MATLAB or other methods to calculate stress (shear, tensile, compressive, etc.) at different locations along the beam using the formula best suited to your analysis.

Here is an example posted to the File Exchange that shows many of the basic steps to obtain necessary values and perform a calculation of the stress in a beam.

https://www.mathworks.com/matlabcentral/fileexchange/76727-simscape-flexible-beam-stress-beamstresslib

Below is a screenshot of the results produced by the example. Thanks to @Alberto Mora for sharing this example. See also this MATLAB Answers Post for an option using PDE Toolbox.

--Steve