4. Contact with the environment

The use of humanoid robots involves managing contact between the robot and its environment. There are many types of contact: intermittent or permanent contact between the feet and the ground, alternating contact, but also contact between the hands or one of the robot's bodies and the environment. Apart from their non-permanent nature, the contacts verify the linkage conditions, and for each degree of freedom, the linkage must be considered as unilateral or bilateral. The mathematical model of the connection between two rigid bodies and their degrees of freedom is given in . The number of degrees of freedom of the connection can change as a function of the interaction. Thus, a unilateral connection removes...