A process and apparatus for positioning an object being moved along a path to a destination using a pole changing three-phase induction motor having at least two fixed driving speeds. The object is initially accelerated along the path of movement to the highest driving speed of the motor
A process and apparatus for determining a load on a lifting mechanism including a load measuring device and a three-phase induction motor operable for lifting and lowering the load. The effective power consumption of the induction motor is determined by the load measuring device base
A control system for a materials-handling device, especially for a shelf storage and retrieval device. The device includes a horizontal travelling mechanism having a horizontal drive; a lift truck which can be raised and lowered on a mast via a lifting drive; and a storage/retrieval driv