[Question] How to get the action space ranges?

[ZaberKo]

Hello,

I'm writing a wrapper for MjxEnv to translate it to another Env API. In brax, we have env.sys.actuator.ctrl_range to get the action range. How to get the action space in MjxEnv? Or, according to #19, should we just use [-1,1]?

[Rian-Jo]

action range is [-1, 1] is correct.

env.sys.actuator.ctrl_range (mujoco engine) is different according to the actuator. in mujoco_playground examples, actuators are set to position. so, ctrl_range is position range. you can check it in xmls. you have to check that action range of environment (MjxEnv) and control range of mujoco engine are different.