Method and system for determining position and orientation of an object

• US 7,990,550 B2
• Filed: 03/03/2006
• Issued: 08/02/2011
• Est. Priority Date: 03/17/2005
• Status: Expired due to Fees

• Current Assignee: Beamrider Limited
• Original Assignee: Leica Geosystems AG (Hexagon AB)
• Inventors: Kipfer, Peter, Aebischer, Beat, Braunecker, Bernhard
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US11/908,792
• Publication Number:
  US 20090231582A1
• Time in Patent Office: 1,978 Days
• Field of Search: 356/4.01, 356/4.09, 356/614, 356/623, 356/625, 356/73, 35613901-13903, 250/202, 250/203.2, 250/221, 359/529
• US Class Current: 356/614
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46

Abstract

The invention relates to a positioning method for determining the position and orientation of a mobile unit having a receiver (3′), whereby the receiver (3′) is detected by a scanner (2′), said scanner (2′) determining at least the distance and a direction in relation to the receiver (3′). The radiation emitted by the sensor is detected by the receiver (3′) and the direction of incidence of radiation and the direction of incidence of radiation in relation to an axis of reception are derived while an offset of the incident radiation in relation to the axis of reception (EA) is determined. Position and orientation of the unit are derived from at least the distance, the direction in relation to the receiver (3′), the offset and the direction of incidence as the position information and the unit is optionally controlled via the optical connection (OV).

Claims

1. An attitude determination method for guiding a movable unit by determining position and orientation of the moveable unit having a receiver including a scanning unit for scanning to detect the receiver by a laser beam, the scanning unit being capable of being positioned at a point of defined position, the receiver being formed for reception of the laser beam and being capable of being mounted on the movable unit, the method comprising:

detecting the receiver by the scanning unit, the scanning unit determining at least a distance and a direction to the receiver;

detecting the laser beam by the receiver and determining a direction of incidence of the laser beam relative to a receiver axis;

determining the position and orientation of the unit from at least the distance, the direction to the receiver and the direction of incidence as attitude information, wherein the position of the impingement point of the laser beam in an entry pupil of the receiver is determined on detection of the laser beam, the entry pupil being large relative to the cross-section of the impingement point of the laser beam; and

generating control commands usable for guiding the movable unit based on the attitude information.

2. An attitude determination method according to claim 1, wherein the scanning unit determines at least the distance by a phase or transit time measuring principle.

3. An attitude determination method according to claim 1, wherein the direction to the receiver is determined with a horizontal receiver angle and a vertical receiver angle, taking into account the position of the impingement point.

4. An attitude determination method according to claim 1, wherein the position of the impingement point is taken into account when determining the position.

5. An attitude determination method according to claim 1, wherein a mean value is calculated for a plurality of values of the position of the impingement point and/or the direction of incidence.

6. An attitude determination method according to claim 1, wherein an inclination measurement is effected during the determination of the position and orientation of the unit.

7. An attitude determination method according to claim 1, wherein the laser beam is emitted with a polarization direction and the polarization direction is detected by the receiver so that the attitude of the receiver relative to the polarization direction can be derived.

8. An attitude determination method according to claim 1, wherein a change in the attitude of the receiver and/or of the unit is controlled so that a predetermined orientation relative to the direction of incidence is included.

9. An attitude determination method according to claim 8, wherein the position and orientation of the unit is changed continuously by tracking the direction of incidence as a control beam.

10. An attitude determination method according to claim 1, further comprising transmitting at least parts of the attitude information from the scanning unit to the receiver and/or the unit, the receiver and/or the unit to the scanning unit, the scanning unit to a control unit and/or the receiver and/or the unit to the control unit.

11. An attitude determination method according to claim 10, wherein the transmission of the at least parts of the attitude information is transmitted via a radio, infrared, ultrasound, or cable link.

12. An attitude determination system for carrying out an attitude determination method according to claim 1, comprising:

a radiation source for emitting a laser beam;

a control component for guiding the laser beam in a scanning movement over a solid angle range;

a measuring component for receiving the reflected laser beam and determining direction and distance to a reflection location of the laser beam, in particular according to the transit time or phase measurement principle; and

communication means for transmitting direction and distance, the control component being formed so that the scanning movement is capable of being freely specified.

13. A moveable unit, comprising:

a support component; and

a receiver for receiving a laser beam, the receiver being adjustable relative to the support component, and the receiver and the support component being formed and arranged so that the direction of incidence of the laser beam relative to a receiver axis is detectable and the position of the receiver relative to the support component is detectable, wherein the receiver is formed so that the position of the impingement point of the laser beam in an entry pupil of the receiver is capable of being determined, the entry pupil being large relative to the cross-section of the impingement point of the laser beam.

14. A movable unit according to claim 13, wherein the support component includes a drive, the receiver is rotatable about one or two axes, and the position of the receiver relative to the support component is detectable by at least one angle sensor.

15. A movable unit according to claim 13, wherein the receiver is formed so that the position of the impingement point is detected together with an angle of incidence of the laser beam.

16. A movable unit according to claim 13, wherein the receiver has an objective lens having at least one radiation-sensitive detector component which is position-sensitive with respect to the laser beam, the detector component being arranged in the focal plane.

17. A movable unit according to claim 16, wherein a beam splitter having at least two radiation-sensitive detector components which are position-sensitive with respect to the laser beam are arranged downstream of the objective lens, the detector components being arranged so as to be oppositely defocused.

18. A movable unit according to claim 13, further comprising a tilt meter.

19. A movable unit according to claim 18, wherein the tilt meter includes a biaxial tilt meter.

20. A movable unit according to claim 13, further comprising an element for reflecting the laser beam.

21. A movable unit according to claim 20, wherein the element for reflecting the laser beam is a reflective region of a receiver optical system of the receiver.

22. A movable unit according to claim 13, wherein the receiver is formed so as to be polarization-sensitive, so that the attitude of the receiver relative to the polarization direction is capable of being derived.

23. A movable unit according to claim 13, further comprising a processing unit for changing a surface.

24. A movable unit according to claim 21, wherein the processing unit is further configured to produce markings on a ground surface.