Contribution à la Conception et l'équilibre des Robot Humanoides

Humanoid robots have been the subject of numerous studies for several decades, and their large-scale deployment in industrial contexts has never been closer.In particular, their human-like form makes them perfect candidates for performing low-value tasks in environments that are difficult to access for other mobile platforms.Thus, we see them appearing in factories where contacts with their upper body limbs, often underutilized, are required and have significant consequences on balance.In this thesis, we address the issues of humanoid robotics related to multi-contact balance and the use of the robot's upper limbs.First, the multi-contact balance is studied through a centroidal model that allows for quick calculations. For this, a balance region in which the center of mass must be located is used. Its shape depends on the position of the robot's contacts as well as the tolerated accelerations of the center of mass. To use it online, a method that improves its calculation is proposed. It is then integrated into the control of the humanoid robot HRP-4.Then, several multi-contact balance approaches are compared to the previous method. In particular, an approximation of the equilibrium region of the center of mass by its Chebyshev center and the associated ball is studied.In the second phase, the capabilities of humanoid robots are enhanced by integrating tool changers. The robot will then be able to autonomously change its effectors, whether they are hands, feet, or even the head.A study of commercially available tool changer models is being conducted.Two models are integrated into the humanoid platform HRP-4.We then establish the specifications for a tool changer that is better suited to the constraints of a humanoid robot.Finally, based on these constraints, a new design for an end-effector changer is proposed. This design has variations aimed at every end-effector of the robots, including hands, feet, and head.It takes advantage of the dexterity of the humanoid robot to lock and unlock the effectors without needing to add extra actuators.The result is demonstrated again on the HRP-4 robot.