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### How to well simulate friction between two surfaces on gazebo?

I'm currently working on a project that needs a bit of friction to run the real environment. But, and it's why I'm here, I have problems.

I'm trying to put a stick on a pad, and I want them to be a bit sticky together, and have some friction between them before the stick falls off.

I precise that I'm new to Gazebo, and I'm open to all of your advices.

Here is the example, were the green pad surface has a friction of mu and mu2 around 10000 (for testing), same for the sphere. I tried to change the visual and collision geometry to see if the problem came from here, without effect.

There is three frames to illustrate the slipperiness of these surface:

I performed some tests to understand the differents parameters (such as mu and mu2 here).

The ramp has these parameters for the first test :

mu : 0.0, mu2: 0.0

I think that these parameters vary between 0 and 1, but when I create a world, the ground has these values.

In each case, cylinders have, in the order, these parameters :

mu : 0.0, mu2: 0.0

mu : 0.1, mu2: 0.1

mu : 0.3, mu2: 0.3

mu : 0.5, mu2: 0.5

mu : 0.8, mu2: 0.8

mu : 1.0, mu2: 1.0

Here, the picture of the first test, when cylinders roll on the ramp :

Here, the 2 pictures of the second test, the first one shows the cylinders rolling down the ramp, and the second one shows what happens after, on the ground :

In the idea, the result will show that the first cylinder will roll slower than the second one, the second one slower than the third and so one and so one. However, this is not happened.

These examples show that the lower mu is taken between two object, but why, for the first test, there is no difference for the cylinders between 3 and 6 ?

Plus, how to simulate the friction for my real application ?

I thank you in advance ! Have a nice day !