How to make a geom invisible to a rangefinder in MuJoCo XLA

[eleninisioti]

Intro

I am a researcher using MuJoCo and brax for simulating reinforcement learning agents

My setup

mujoco-mjx 3.2.4

My question

I see in the documentation that you can make an object invisible to sensors by setting the last element of its rgba property to 0. But I had the impression that you can also make geoms invisible to a sensor by setting the collision dynamics appropriately. I tried to do so in this way and failed: I have a rangefinder sensor that I add as a site under a body tag whose contype and conaffinity are 2 and there is another body (called 'food' in my xml) i whose contype and conaffinity is 1. I thought that would make the item invisible to the sensor but it is not the case. (I am attaching the xml file that is used by brax to run the simulation).

If the only way of controlling visibility is through the rgba property, then it is not possible to make an object invisible to some sensors and not others, right? Also it would be nice if I can render the object even though it's invisible, but I imagine this should be possible to adjust when visualizing.

Minimal model and/or code that explain my question

<site name="rangefinder_0_offset_0" pos="-0.14142136 0.14142136 0" quat="0.27059805393218994 -0.6532814502716064 0.27059805393218994 0.6532815098762512" rgba="1 0 0 1" />

Confirmations

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