#instantaneous axis

• Axoid — A remarkable ruled surface generated during the three-dimensional movement of a rigid body by the succession of consecutive positions occupied by the instantaneous axis of rotation and translation. In theoretical mechanics and kinematics, any complex structural movement of a solid can be rigorously described by the rolling without slipping of a moving axoid attached to the body over a fixed axoid integrated into the reference space, providing a highly precise geometric model for gear analysis.