Laser reference system

• US 8,605,274 B2
• Filed: 01/24/2011
• Issued: 12/10/2013
• Est. Priority Date: 01/24/2011
• Status: Active Grant

• Current Assignee: Spectra Precision Inc. (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Schumacher, Lars
• Primary Examiner(s): Chowdhury, Tarifur
• Assistant Examiner(s): AKANBI, ISIAKA O
• Application Number:
  US13/012,364
• Publication Number:
  US 20120188535A1
• Time in Patent Office: 1,051 Days
• Field of Search: 356140-141, 3561413-1414, 141/386
• US Class Current: 356/140
• CPC Class Codes: G01C 15/004 Reference lines, planes or sectors

Abstract

A method of operating a laser reference system orients a reference plane of laser light generated by a transmitter so compensation is made for rake angles between the first and second axes of the transmitter and first and second non-orthogonal alignment axes. The transmitter includes an optical system arranged to generate a laser beam, the optical system projecting said laser beam radially along a rotational arc defined about a central rotational axis, thereby substantially defining a reference plane of laser light, and a positioning arrangement, coupled to said optical system, for adjusting the angular orientation of the optical system with respect to a first transmitter axis and with respect to a second transmitter axis. Detectors are arranged to detect reception of the laser beam.

Claims

1. A method of orienting a reference plane of laser light generated by a transmitter, the transmitter including a positioning arrangement that adjusts the angular orientation of the reference plane with respect to a first transmitter axis and with respect to a second transmitter axis perpendicular thereto, the laser light being detected by first and second detectors, comprising the steps of:

defining a first alignment direction from said transmitter by positioning said first detector in said first alignment direction for illumination with said plane of laser light;

defining a second alignment direction from said transmitter by positioning said second detector in said second alignment direction for illumination with said plane of laser light;

determining with a processor the orientation of said first alignment direction with respect to said first and second transmitter axes;

determining with a processor the orientation of said second alignment direction with respect to said first and second transmitter axes, including the steps of determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the second detector, and determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the second detector;

specifying the desired orientation of said reference plane in said first and second alignment directions;

determining with a processor the angular orientation of said reference plane with respect to said first transmitter axis and with respect to said second transmitter axis needed to position said reference plane in said desired orientation; and

orienting said reference plane with respect to said first and second transmitter axes such that said desired orientation of said reference plane in said first and second alignment directions is achieved.

2. The method of claim 1, in which said step of determining the orientation of said first alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the first detector, and

determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the first detector.

3. The method of claim 1 in which the step of determining the angular orientation of said reference plane with respect to said first transmitter axis and with respect to said second transmitter axis needed to position said reference plane in said desired orientation comprises the step of using the equations:

4. A method of orienting a reference plane of laser light generated by a transmitter, the transmitter including a positioning arrangement that adjusts the angular orientation of the reference plane with respect to a first transmitter axis and with respect to a second transmitter axis perpendicular thereto, the laser light being detected by first and second detectors, comprising the steps of:

defining a first alignment direction from said transmitter by positioning said first detector in said first alignment direction for illumination with said plane of laser light, said first detector further defining the grade of the reference plane of laser light by its vertical position with respect to said transmitter;

defining a second alignment direction from said transmitter by positioning said second detector in said second alignment direction for illumination with said plane of laser light, said second detector further defining the grade of the reference plane of laser light by its vertical position with respect to said transmitter;

determining with a processor the orientation of said first alignment direction with respect to said first and second transmitter axes;

determining with a processor the orientation of said second alignment direction with respect to said first and second transmitter axes, including the steps of determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the second detector, and determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the second detector;

orienting said reference plane in said first alignment direction such that said first detector is illuminated;

orienting said reference plane in said second alignment direction such that said second detector is illuminated;

determining with a processor the angular orientation of said reference plane with respect to said first transmitter axis and with respect to said second transmitter axis that results when both said first detector and said second detector are simultaneously illuminated; and

determining with a processor the resulting orientation of said reference plane in both said first alignment direction and said second alignment direction.

5. The method of claim 4, in which said step of determining the orientation of said first alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination of the direction of said first and second transmitter axes of a first plane which is detected by the first detector, and

determining the inclination of the direction of said first and second transmitter axes of a second plane which is detected by the first detector.

6. The method of claim 4 in which the step determining the resulting orientation of said reference plane in both said first alignment direction and said second alignment direction comprises the step of using the equations:

7. A method of orienting a reference plane of laser light generated by a transmitter, the transmitter including a positioning arrangement that adjusts the angular orientation of the reference plane with respect to a first transmitter axis and with respect to a second transmitter axis perpendicular thereto, the laser light being detected by first and second detectors, comprising the steps of:

defining a first alignment direction from said transmitter by positioning said first detector in said first alignment direction for illumination with said plane of laser light;

defining a second alignment direction from said transmitter by positioning said second detector in said second alignment direction for illumination with said plane of laser light;

determining with a processor the orientation of said first alignment direction with respect to said first and second transmitter axes;

determining with a processor the orientation of said second alignment direction with respect to said first and second transmitter axes;

specifying the desired orientation of said reference plane in said first and second alignment directions;

determining with a processor the angular orientation of said reference plane with respect to said first transmitter axis and with respect to said second transmitter axis needed to position said reference plane in said desired orientation using the equations;

8. The method of claim 7, in which said step of determining the orientation of said first alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the first detector, and

determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the first detector.

9. The method of claim 7, in which said step of determining the orientation of said second alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the second detector, and

determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the second detector.

10. A method of orienting a reference plane of laser light generated by a transmitter, the transmitter including a positioning arrangement that adjusts the angular orientation of the reference plane with respect to a first transmitter axis and with respect to a second transmitter axis perpendicular thereto, the laser light being detected by first and second detectors, comprising the steps of:

defining a first alignment direction from said transmitter by positioning said first detector in said first alignment direction for illumination with said plane of laser light, said first detector further defining the grade of the reference plane of laser light by its vertical position with respect to said transmitter;

defining a second alignment direction from said transmitter by positioning said second detector in said second alignment direction for illumination with said plane of laser light, said second detector further defining the grade of the reference plane of laser light by its vertical position with respect to said transmitter;

determining with a processor the orientation of said first alignment direction with respect to said first and second transmitter axes;

determining with a processor the orientation of said second alignment direction with respect to said first and second transmitter axes;

orienting said reference plane in said first alignment direction such that said first detector is illuminated;

orienting said reference plane in said second alignment direction such that said second detector is illuminated;

determining with a processor the angular orientation of said reference plane with respect to said first transmitter axis and with respect to said second transmitter axis that results when both said first detector and said second detector are simultaneously illuminated; and

determining with a processor the resulting orientation of said reference plane in both said first alignment direction and said second alignment direction using the equations;

11. The method of claim 10, in which said step of determining the orientation of said first alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the first detector, and

determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the first detector.

12. The method of claim 10, in which said step of determining the orientation of said second alignment direction with respect to said first and second transmitter axes includes the steps of:

determining the inclination in the direction of said first and second transmitter axes of a first plane which is detected by the second detector, and

determining the inclination in the direction of said first and second transmitter axes of a second plane which is detected by the second detector.