  We consider dynamic stair climbing with the HRP-4 humanoid robot as part of
an Airbus manufacturing use-case demonstrator. We share experimental knowledge
gathered so as to achieve this task, which HRP-4 had never been challenged to
before. In particular, we extend walkingstabilization based on linear inverted
pendulum tracking by quadratic programming-based wrench distribution and a
whole-body admittance controller that applies both end-effector and CoM
strategies. While existing stabilizers tend to use either one or the other, our
experience suggests that the combination of these two approaches improves
tracking performance. We demonstrate this solution in an on-site experiment
where HRP-4 climbs an industrial staircase with 18.5 cm high steps, and release
our walking controller as open source software.
