how to use the Simscape-M​ultibody-C​ontact-For​ces_librar​y?

Hey all,

I am trying to simulate a cart driving on an infinite plane (contact between 4 wheels and the plane). i saw I could use the Simscape-Multibody-Contact-Forces_library to do so, but having some problems.

i've downloaded the library, and ran the project. when using the "Sphere to Plane Force" block from the examples, it runs fine. but when I move it to my own model, I see that the values inside are missing (for example, the values for "Transform nZ", "Transform pZ" and so on.

my question is, where can I find this parameters? or how can I add them to my path?

this is the error i'm seeing:

['cart_inv_pend']: The following errors were found in the model cart_inv_pend.

Caused by:

• ['cart_inv_pend/cart1/Sphere to Plane WheelRF/Transform nZ']: The parameter Offset requires a scalar, not a 0 x 0 matrix. Resolve this issue in order to simulate the model.
• ['cart_inv_pend/cart1/Sphere to Plane WheelRF/Transform pZ']: The parameter Offset requires a scalar, not a 0 x 0 matrix. Resolve this issue in order to simulate the model.
• ['cart_inv_pend/cart1/Sphere to Plane WheelRF/Visual PlaBnZ']: The parameter Geometry/Size requires a 3-vector, not a 2-vector. Resolve this issue in order to simulate the model.
• ['cart_inv_pend/cart1/Sphere to Plane WheelRF/Visual PlaBpZ']: The parameter Geometry/Size requires a 3-vector, not a 2-vector. Resolve this issue in order to simulate the model.

thanks :-)

[Giovanni Forin]

hi, please tell me that you solved this issue. For no reason when i opened back my model it keeps giving me the same issue. I beg you

Answer 1

[Orel Levy]

Hi, So I've noticed the parameters i'm looking for exist in the library's model workspace.

after copying the parameters to my model's workspace, It worked perfect

[Giovanni Forin]

I noticed the same after i wrote you sorry. Eventually for a quick solution it´s possible to enable the visualization (enabling the Visual PlaBpZ variable) update the model and then disable it, but the variable Visual PlaBpZ is still in the workspace.

Answer 2

[Sabine]

Hi, I am currently facing this same issue, but I can't find the parameters in de model workspace of the library. I went through all folders, library files and examples, but nothing looks like the missing parameters. Could you please point out where exactly you found it? Thanks in advance!

[Orel Levy]

the parameters are all defined inside the mask.

to be honest I can't remember exactly what I did that solved the issue, and I can't recreate it.

if you could send me a model where you see this issue, I could try it again and remember what I did :-)