Validation of superquadric contact force calculation [Podlozhnyuk et al. (2017)]

Submitted by lumblab227 on Sat, 01/12/2019 - 15:43

I have read the paper by Podlozhnyuk et al. (2017) and curious about the contact force calculation.

Referring to Fig. 6, it is shown that different results of adopting different radius method.

And I have written a script to examine the results.

However I have got the results of the volume equivalent sphere. And I could see the big difference from the FEM results if I keep increasing the overlap.

Is there any comment on it?

Or it would be appreciated if you could give your experience on examine it?

Kind regards,

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lumblab227 | Sun, 01/13/2019 - 03:40

The problem has been solved.

Still, using gaussian radius is not the best choice, and there is some improvement on implementing superquadric features.

arnom's picture

arnom | Mon, 01/14/2019 - 11:57

Can you please provide us with concrete ideas/code on how to improve the SQ feature?

KR,
Arno

DCS team member & LIGGGHTS(R) core developer

lumblab227 | Tue, 01/15/2019 - 11:02

I thought using equivalent radius is not the best way, personally.

I have read some papers and want to improve the code by numerically calculating the ratio of semi-axis of the contact profile, which is an ellipse.

By knowing the ratio, say Alpha, it is now ready to calculate the first and second kind of ellipse integral. If you have interest, I could let you have my derivation and pseudo code.

I am now doing the modification and see if it actually works.

I will let you know the result in about a week.

KInd regards,
Lumb