Human safety mechanisms of human-friendly robots: Passive viscoelastic trunk and passively movable base

We would like to give robots the ability to secure human safety in human-ro bot collisions capable of arising in our living and working environments. H owever, unfortunately, not much attention has been paid to the technologies of human robot symbiosis to dare because almost all robots have been desig ned and constructed on the assumption that the robots are physically separa ted from humans. A robot with a new concept will be required to deal with h uman-robot contact. In this article, we propose a passively movable human-f riendly robot that consists of an elastic material-covered manipulator pass ive compliant trunk, and passively movable base. The compliant trunk is equ ipped with springs and dampers, and the passively movable base is constrain ed by friction developed between the contact surface of the base and the gr ound. During unexpected collisions, the trunk and base passively move in re sponse to the produced collision force We describe the validity of the mova ble base and compliant trunk for collision force suppression, and it is dem onstrated in several collision situations.