An axis of a motion device is the mechanical joint of a manipulator that performs a linear or a rotational movement.
Power trains, consisting of gears, motors and drives, are responsible for the movement of axes. Drives can be integrated in the manipulator or inside a controller cabinet. References describe the relationships between the components of the power train.
Figure B.10 shows two possibilities for a realization of a linear two-dimensional motion device. While in the left figure there is a 1:1 relation between power train and mechanical axis in the right figure power train 1 and power train 2 have effect on the movement of axis 1 and on axis 2. An additional load is located on the mechanical axis 2 but has effect on both power trains.
References describe the relationships between the movement of axes and the power trains that initiate the movement.