Robots climbing stairs is pretty standard these days. Most quadruped platforms support that. Things are a bit more complicated when it comes to climbing ladders. Researchers have now come up with a learning-based control approach for quadrupeds climbing ladders. They used a hooked end effector.
This robot had a 90% success rate at ladder angles from 70 to 90 degrees (zero-shot transfer). The above video from Robotic Systems Lab shows this system in action. As you can see, the robot can recover and continue climbing when being pulled by a human.
[HT]