Walking robots are one of my favorites. There was a brave Korean gentleman that designed a simplified version of Boston Dynamics’ Spot mini, called the spot micro. I needed to build that:
When working on my version of the spotmicro, I noticed that the community is developing the gait patterns and inverse kinematics using simulators, here’s an example:
I’ve also read about pyBullet , Gazebo , MoJuCo but never was sure what they actually do and how deep they go, not only in terms of physics simulation but also for sensors / cameras as well as the learning of motor patterns or visual processing.