公开(公告)号：US20210055104A1

公开(公告)日：2021-02-25

申请号：US16998958

申请日：2020-08-20

Applicant: LEICA GEOSYSTEMS AG

Inventor： Benjamin MÜLLER ,  Thomas Lienhard SCHMITT ,  Christoph HERBST ,  Hannes Martin WACHTER

IPC: G01C15/00 ,  B25F5/00 ,  B25B21/00

Abstract: A geodetic surveying instrument to move a measurement light beam into a desired measurement direction in space, comprising at least one movement axis which is motorized, providing a positioning of the measurement direction of the geodetic surveying instrument, and an instrument-encoder at the movement axis configured for deriving the measurement direction as a measurement value of the geodetic surveying instrument. The geodetic surveying instrument comprises a transmission link of the movement axis of the geodetic surveying instrument to a motor axis of a stepper motor, which transmission link is configured with a gear reduction and a slipping clutch arrangement, and wherein the stepper motor comprises a rotational motor-encoder on its motor-axis and is driven by a motor controller that provides a field oriented control of phase currents of the stepper motor, which field orientation is derived based on the rotational motor-encoder.