flexcomp MJCF error, model does not work

[veyselcemilcolak]

Intro

Hi!

I am a graduate student, I use MuJoCo for Master's Thesis.

My setup

Mujoco 3.3.0, OpenSUSE 15, x86, simulation GUI through /bin

My question

Hi,

I wanted to implement soft version of pendulum code using flexcomp. I tried differrent things and all fail:

What I wanted to do : soft version of pendulum.xml and ScPendulum.png

1)Tried pendulum_try3b.xml ---> (ScError.png) Error: mass and inertia of moving bodies must be larger than mjMINVAL)
2) Tried pendulum_try3c.xml --->(ScError.png) Error: mass and inertia of moving bodies must be larger than mjMINVAL)
3) Tried pendulum_try3.xml -----> Does not show any error and opens the simulation but the soft object is not fixed although I have added the body as child. It collapses directly. Please see ScFail0,1,2.png
pendulum_soft_error.zip

Files are attached in .zip (It can require scene.xml in standard library, you can move the xml files into mujocxxx/model/flex folder.)

Thanks in advance,

Minimal model and/or code that explain my question

Confirmations

• I searched the latest documentation thoroughly before posting.
• I searched previous Issues and Discussions, I am certain this has not been raised before.

[quagla]

Hi, I think what you want is the following

first body
joint
geom
second body
no joint
flex pinned to the second body

Let me know if that works

[veyselcemilcolak]

pendulum_try3d .txt

I have tried this and works, we speak most probably the same thing.