In several of the default examples, there’s a gravity vector in the yaml file of the task (e.g. anymal.yaml), but changing it (e.g. to have positive gravity) doesn’t actually affect the simulation.
Following into the python code, gravity is parsed in
sim_options (~line 390), which is then sent through
parse_physx_config(sim_cfg["physx"], sim_options). In
parse_physx_config, it seems to me that this is actually just thrown away…?