How to return a warning flag variable when the simulation becomes unstable

[yinfanyi]

Intro

Hi!

I am a undergrad student, I use MuJoCo for my research on Parallel mechanism simulation.

My setup

MuJoCo version 3.2.2

My question

My simulation sometimes encounters crashes. How can I return a variable to indicate that the simulation is unstable when a crash occurs, and then terminate the simulation instead of restarting it.

Minimal model and/or code that explain my question

No response

Confirmations

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

[yuvaltassa]

We have a WIP change which will make mj_step and related functions return an enum rather than void, and you could check that enum to check if anything bad happened. Would that solve your issue?

In the meantime, you can check mjData.warning after every step. Even though by default divergence triggers a reset, the warning array will be incremented.

[yinfanyi]

thanks a lot, it solves my issue!