Robot legs called Cassie have become one of the new R&D project of Boston Dynamic next to spot, atlas and other fantastic creations. Two-legged robot learned a range of movement from scratch including crouching with a load
Despite the multiple simulations in virtual environments the transfer the models into the real world is a bit tricky, small differences of for example friction can trip over the robot due to the lacking data from simulation. when a robot tries to apply what it has learned. A heavy two-legged robot can lose balance and fall if its movements are even a tiny bit off.
In this case Boston dynamics applied double simulation where the Cassie learned from the virtual and real environment. The data collected from the real world was transferred to environment called SimMechanics that mirrors real-world physics with high degree of accuracy
The real Cassie was able to walk using the model learned in simulation without any extra fine-tuning. It could walk across rough and slippery terrain, carry unexpected loads, and recover from being pushed. During testing, Cassie also damaged two motors in its right leg but was able to adjust its movements to compensate.
Refference:
Interesting that people make technologies and robots inspired by nature/existing creatures.