Some embodiments are directed to a lower limb articulation for bipedal locomotion, which includes a first element a second element and articulation devices for articulating the first and second elements relative to one another, the articulation devices including an articulation mechanism including first and second linking devices mounted in series, as well as devices for guiding and locking in position one of the first and second elements relative to the other one of the first and second elements when the lower limb comes to rest on a surface, the devices for locking in position including a potential trough.