Stores for items in the form of raw materials or basic components, which comprises: - a plurality of item storage areas, at least one storage area, referred to as upper, being superimposed on at least one storage area, referred to as lower, each storage area comprising a number of item storage locations formed on the floor of said storage area; - at least one carrier able to move items from an upper storage area to a lower storage area, and vice versa; - for each upper storage area, at least one manipulator robot able to pick up an item from one of the storage locations and transport it to a carrier, and vice versa; and - for each lower storage area, at least one manipulator robot able to pick up an item from one of the storage locations and transfer it to a workstation, and vice versa, and able to pick up an item from the carrier and transport it to one of the storage locations or to a workstation, and vice versa, each manipulator robot being able to move over a storage area during the transport; wherein at least one manipulator robot is mounted so as to be mobile on two horizontal rails fixedly installed above and at a distance from the storage area and above two sides of said storage area, this manipulator robot comprising a motorized horizontal base mounted so as to be mobile on the two rails, said horizontal base being formed of two side-members perpendicular to the direction of the guide rails, said manipulator robot also comprising a motorized carriage mounted so as to be mobile on and along the two side-members of the motorized horizontal base, said motorized carriage bearing a grasping head movable from bottom to top and vice versa; wherein the grasping head comprises a gripper comprising two opposed grasping claws, two vertical carrying arms respectively bearing the two grasping claws on their lower extremity, and an actuator motor mechanism (223, 224) for moving the two carrying arms further from or closer to each other; characterized in that the actuator motor mechanism comprises a motor unit having a rotary output shaft coupled to a horizontal actuator screw, fixed in translation, comprising two opposed threaded areas, one of which has a right thread and the other a left thread, each threaded area receiving a threaded bush, fixed in rotation, one of the two carrying arms being borne by one of the threaded bushes and the other by the other threaded bush, and said carrying arms extending downwards from the threaded bushes. - a plurality of item storage areas, at least one storage area, referred to as upper, being superimposed on at least one storage area, referred to as lower, each storage area comprising a number of item storage locations formed on the floor of said storage area; - at least one carrier able to move items from an upper storage area to a lower storage area, and vice versa; - for each upper storage area, at least one manipulator robot able to pick up an item from one of the storage locations and transport it to a carrier, and vice versa; and - for each lower storage area, at least one manipulator robot able to pick up an item from one of the storage locations and transfer it to a workstation, and vice versa, and able to pick up an item from the carrier and transport it to one of the storage locations or to a workstation, and vice versa,