Method and device for target seeking for geodetic devices

• US 6,133,998 A
• Filed: 07/30/1998
• Issued: 10/17/2000
• Est. Priority Date: 08/01/1997
• Status: Expired due to Term

• Current Assignee: Trimble Jena GmbH (Trimble Inc.)
• Original Assignee: CARL Zeiss JENA GmbH (Carl-Zeiss-Stiftung)
• Inventors: Goering, Hermann, Donath, Bernd, Marold, Thomas, Laabs, Steffen, Monz, Ludwin-Heinz, Seeber, Marcel
• Primary Examiner(s): Buczinski, Stephen C.
• Application Number:
  US09/126,211
• Time in Patent Office: 810 Days
• Field of Search: 356/141.1-141.5, 356/152.1-152.3
• US Class Current: 356/141.4
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105

Abstract

A method for target seeking in geodetic survey measurements comprises the steps of generating at least a first light bundle by a measurement device from a light source arranged therein, the light bundle periodically pivoting back and forth or revolving about the standing axis of the measurement device and fanning out in the vertical plane and being sent to at least one receiver arrangement arranged in at least one target station arranged at a distance from the measurement device. The steps of the method also include generating an electrical signal when the light bundle hits the receiver arrangement of the at least one target station, conveying these electrical signals generated in the target station, or the time difference determined from these electrical signals to the measurement device through a transmitting device provided in the target station, determining the horizontal angle to the respective sighted target station from the time difference of two electrical signals generated one after the other in time by angles measured or stored at constant time intervals and pivoting a second modulated light bundle at an angle in the vertical plane and sending it in the direction of the target station for determining the vertical angle of the measurement device. Further, when the second light bundle hits the receiver arrangement in the target station, the method includes the step of generating another electrical signal and sending it to the measurement device and determining the vertical angle to the respective target station therefrom in the measurement device. Also disclosed is a device in accordance with the method.

Claims

1. A method for target seeking in geodetic survey measurements, comprising the steps of:

generating at least a first light bundle by a measurement device from a light source arranged therein, said light bundle periodically pivoting back and forth or revolving about the standing axis of the measurement device and fanning out in the vertical plane and being sent to at least one receiver arrangement arranged in at least one target station arranged at a distance from the measurement device;

generating an electrical signal when the light bundle hits the receiver arrangement of the at least one target station;

conveying these electrical signals generated in the target station, or the time difference determined from these electrical signals, to the measurement device through a transmitting device provided in the target station;

determining the horizontal angle to the respective sighted target station from the time difference of two electrical signals generated one after the other in time by means of angles measured or stored at constant time intervals;

pivoting a second modulated light bundle at an angle in the vertical plane and sending it in the direction of the target station for determining the vertical angle of the measurement device; and

when the second light bundle hits the receiver arrangement in the target station, generating another electrical signal and sending it to the measurement device and determining the vertical angle to the respective target station therefrom in the measurement device.

2. The method according to claim 1, wherein said second modulated light bundle has a width and height that are substantially the same;

and said method further comprises the step of directing, prior to pivoting the second modulated light bundle, the second modulated light bundle at the determined horizontal angle.

3. A device for target seeking for geodetic survey devices which have a telescope and form the measurement station and which communicate with at least one target station, wherein the geodetric device is rotatable about a standing axis and comprises:

means for generating at least one light bundle to be sent in the target station;

a receiver arrangement being provided at the target station, said receiver arrangement for generating electrical signals when the light bundle impinges;

transmission and reception devices being provided at the measurement station and at the target station for transmitting information and signals;

a transmitting unit connected with the geodetic device being provided for generating a first light bundle which is fanned out in the vertical direction and pivotable in the horizontal plane;

said telescope of the device, which telescope is pivotable about a trunnion axis being provided for generating a second light bundle in a vertical plane;

a data radio unit being arranged at the measurement station and serving to receive signals sent from the target station; and

a photoelectric receiver arrangement, a reflector and an electronic unit with storage and data radio unit being arranged at the target station for storing and conveying data and signals to the measurement station.

4. The device according to claim 3, wherein the transmitting unit of the measurement station has a light source, a collimating objective, and an optical system which expands the first light bundle in the vertical plane and which has a cylindrical lens.

5. The device according to claim 3, wherein the receiver arrangement of the target station comprises an objective and an arrangement having CCD elements or a spatially sensitive photoreceiver, wherein a light filter is arranged before the objective, and the receiver arrangement is connected with the electronic unit and with the data radio unit.

6. The device according to claim 3, wherein the light of the light bundles is modulated.

7. The device according to claim 3, wherein the measurement station includes means for determining a horizontal angle to the target station from the information and signals transmitted to the measurement station;

the second light bundle generated by the telescope has a width and height that are substantially the same; and

said telescope further includes means for directing, prior to pivoting the telescope about the trunnion axis, the second light bundle at the determined horizontal angle.