Some questions about the settings in the XML files

[zichunxx]

Hi! Thanks for your generous sharing!

When I read the XML files, I noticed there are a lot of duplications of the body, such as the indicator link, dummy link or joint, goal link or joint.

What are the differences between the above settings and the real link or joint? In other words, what's the role of the above settings in the RL simulation?

Looking forward to your reply!

[junjungoal]

@QUIlToT
Hi, thank you for the question. Those are used just for visualization and are not related to RL training.
I think dummy links are not used, because the alpha value in XML is zero. The goal links are for visualization of the goal position specified for motion planning.

[zichunxx]

Hi, thank you for the question. Those are used just for visualization and are not related to RL training.
I think dummy links are not used, because the alpha value in XML is zero. The goal links are for visualization of the goal position specified for motion planning.

Thank you for your reply! Since the dummy links are not used, why is the dimension of observation space 16 instead of 12?

Also, probably because I'm new to this, I didn't find the alpha value in the XML file.