Surveying system and method

• US 9,541,392 B2
• Filed: 10/15/2013
• Issued: 01/10/2017
• Est. Priority Date: 10/18/2012
• Status: Active Grant

• Current Assignee: Leica Geosystems AG (Hexagon AB)
• Original Assignee: Leica Geosystems AG (Hexagon AB)
• Inventors: Dusha, Damien
• Primary Examiner(s): GUADALUPE, YARITZA
• Application Number:
  US14/436,445
• Publication Number:
  US 20150268045A1
• Time in Patent Office: 1,183 Days
• Field of Search: 332/90, 33D/IG.21
• US Class Current: 1/1
• CPC Class Codes: G01C 15/06 Surveyors' staffs; Movable markers
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems

Abstract

Surveying system for measuring the position of a measuring point on the ground is disclosed. The surveying system may include a survey pole with a body having a pointer tip for contacting the measuring point and position giving means for making available the coordinative determination of a referenced position, being placed on the body with a defined spatial relationship relative to the tip. Determination means may be included for repeatedly determining the referenced position of the position giving means. Evaluation means may also be included for deriving the position of the measuring point. In some embodiments, the survey pole may also include an inertial measuring unit placed on the body with a defined spatial relationship relative to the position giving means.

Claims

1. A surveying system for measuring the position of a measuring point on the ground, the surveying system comprising:

a survey pole including;

a body having a pointer tip for contacting the measuring point; and

position giving means for making available the coordinative determination of a referenced position, the position giving means being placed on the body with a defined spatial relationship relative to the tip, wherein the position giving means comprise a retro reflector and/or a GNSS-antenna,

determination means for repeatedly determining the referenced position of the position giving means; and

evaluation means for deriving the position of the measuring point at least based on the determined referenced position and on the defined spatial relationship of the position giving means relative to the tip;

wherein the survey pole further comprises an inertial measuring unit placed on the body with a defined spatial relationship relative to the position giving means,

wherein the inertial measuring unit comprises IMU-sensors including accelerometers and gyroscopes,

wherein the surveying system further comprises IMU-processing means for repeatedly determining inertial state data based on measurements taken by the inertial measuring unit and in that the evaluation means are further configured to

feed a predefined filter algorithm with the repeatedly determined referenced position and the repeatedly determined inertial state data and deriving therefrom referenced attitude data for the survey pole, taking into account the defined spatial relationship of the inertial measuring unit relative to the position giving means,

use a Divided Difference Filter within the predefined filter algorithm, and

further use the referenced attitude data for deriving the position of the measuring point.

2. The surveying system according to claim 1, wherein:

the inertial measuring unit is designed in form of a micro-electro-mechanical system and comprises IMU-sensors including accelerometers and gyroscopes.

3. The surveying system according to claim 1, wherein:

the inertial measuring unit comprises inertial sensors of tactical grade or lower accuracy.

4. The surveying system according to claim 1, wherein:

the inertial measuring unit comprises inertial sensors of industrial grade or lower accuracy.

5. The surveying system according to claim 1, wherein:

the inertial measuring unit comprises at least three accelerometers in a mutually orthogonal configuration and at least three gyroscopes in a mutually orthogonal configuration,

the IMU-processing means are configured for determining inertial attitude, inertial velocity data and inertial position data as part of the inertial state data, and/or

the evaluation means are further configured for deriving a referenced yaw angle as well as a referenced pitch angle and a referenced roll angle of the survey pole as the referenced attitude data.

6. The surveying system according to claim 1, wherein:

the inertial measuring unit further comprises at least one magnetometer, and

wherein the IMU-processing means are configured for determining also compass-attitude data as part of the inertial state data.

7. The surveying system according to claim 1, wherein:

the inertial measuring unit further comprises two or three magnetometers in a mutually orthogonal configuration, and

wherein the IMU-processing means are configured for determining also compass-attitude data as part of the inertial state data.

8. The surveying system according to claim 1, wherein:

the IMU-processing means are configured for repeatedly determining the inertial state data at an equal or a higher rate than the determination means the referenced position, and

the evaluation means are configured for feeding the predefined filter algorithm with the repeatedly determined inertial state data with an equal or a higher rate than with the repeatedly determined referenced position.

9. The surveying system according to claim 1, wherein the position giving means comprise a retro reflector, wherein:

the determination means comprise a total station or a tachometer for measuring the referenced position of the retro reflector.

10. The surveying system according to claim 1, wherein the position giving means comprise a GNSS-antenna,

wherein the determination means comprise a GNSS-processing unit for processing output-signals of the GNSS-antenna and deriving therefrom the referenced position of the GNSS antenna.

11. An upgrade kit for a surveying system for measuring the position of a measuring point on the ground, the upgrade kit being adapted for detecting attitude data, the surveying system comprising:

a survey pole with;

a body having a pointer tip for contacting the measuring point and

position giving means for making available the coordinative determination of a referenced position, the position giving means being placed on the body with a defined spatial relationship relative to the tip, wherein the position giving means comprise a retro reflector and/or a GNSS-antenna,

determination means for repeatedly determining the referenced position of the position giving means and

first evaluation means for deriving the position of the measuring point at least based on the determined referenced position and on the defined spatial relationship of the position giving means relative to the tip, wherein;

the upgrade kit comprises;

an inertial measuring unit to be placed on the body with a defined spatial relationship relative to the position giving means, wherein the inertial measuring unit comprises IMU-sensors including accelerometers and gyroscopes,

IMU-processing means for repeatedly determining inertial state data based on measurements taken by the inertial measuring unit, and

second evaluation means configured for;

receiving the repeatedly determined referenced position and the repeatedly determined inertial state data,

feeding a predefined filter algorithm with the repeatedly determined referenced position and the repeatedly determined inertial state data and deriving therefrom referenced attitude data for the survey pole, taking into account the defined spatial relationship of the inertial measuring unit relative to the position giving means,

using a Divided Difference Filter within the predefined filter algorithm, and

using the referenced attitude data for deriving the position of the measuring point.

12. The upgrade kit according to claim 11, further comprising:

attaching means for attaching the upgrade kit or parts thereof to the survey pole.

13. The upgrade kit according to claim 11, further comprising:

means for detecting and/or defining a spatial relationship of the inertial measuring unit relative to the position giving means.

14. The upgrade kit according to claim 11, further comprising:

attaching means for attaching the inertial measuring unit to the survey pole.

15. A surveying module for a surveying system for measuring the position of a measuring point on the ground, the surveying module being adapted for detecting attitude data, wherein:

the surveying system comprises a survey pole with a body having a pointer tip for contacting the measuring point, and

the surveying module comprises;

position giving means for making available the coordinative determination of a referenced position, wherein the position giving means are to be placed on the body with a defined spatial relationship relative to the tip, wherein the position giving means comprise a retro reflector and/or a GNSS-antenna,

determination means for repeatedly determining the referenced position of the position giving means and

evaluation means for deriving the position of the measuring point at least based on the determined referenced position and on the defined spatial relationship of the position giving means relative to the tip, wherein;

the surveying module further comprises;

an inertial measuring unit to be placed on the body with a defined spatial relationship relative to the position giving means, wherein the inertial measuring unit comprises IMU-sensors including accelerometers and gyroscopes, and

IMU-processing means for repeatedly determining inertial state data based on measurements taken by the inertial measuring unit, wherein the evaluation means are configured for;

receiving the repeatedly determined referenced position and the repeatedly determined inertial state data,

feeding a predefined filter algorithm with the repeatedly determined referenced position and the repeatedly determined inertial state data and deriving therefrom referenced attitude data for the survey pole, taking into account the defined spatial relationship of the inertial measuring unit relative to the position giving means,

using a Divided Difference Filter within the predefined filter algorithm, and

using the referenced attitude data for deriving the position of the measuring point.

16. A surveying method for measuring the position of a measuring point on the ground, with the help of a survey pole comprising:

a body having a pointer tip for contacting the measuring point and

position giving means for making available the coordinative determination of a referenced position, the position giving means being placed on the body with a defined spatial relationship relative to the tip, wherein the position giving means comprise a retro reflector and/or a GNSS-antenna,

the method comprising;

repeatedly determining the referenced position of the position giving means;

deriving the position of the measuring point at least based on the determined referenced position and on the defined spatial relationship of the position giving means relative to the tip, wherein the survey pole further comprises an inertial measuring unit placed on the body with a defined spatial relationship relative to the position giving means, wherein the inertial measuring unit comprises IMU-sensors including accelerometers and gyroscopes;

repeatedly determining inertial state data based on measurements taken by the inertial measuring unit;

feeding a predefined filter algorithm with the repeatedly determined referenced position and the repeatedly determined inertial state data and deriving therefrom referenced attitude data for the survey pole, taking into account the defined spatial relationship of the inertial measuring unit relative to the position giving means; and

using the referenced attitude data for deriving the position of the measuring point, wherein a Divided Difference Filter is used within the predefined filter algorithm.

17. The surveying method according to claim 16, wherein the inertial measuring unit:

is designed in form of a micro-electro-mechanical system, and/or

comprises inertial sensors of tactical grade or lower accuracy.

18. The surveying method according to claim 16, wherein:

the referenced attitude data is represented by a referenced yaw angle, a referenced pitch angle and a referenced roll angle of the survey pole.

19. The surveying method according to claim 16, wherein:

inertial position data and inertial attitude data are determined as part of the inertial state data, wherein the IMU-sensor error parameters are determined based on an error model for the IMU-sensors including at least one of;

sensor-bias,

sensitivity errors,

misalignment,

non-linearity errors, and

gyroscopes acceleration sensitivity.

20. One or more non-transitory computer-readable media storing one or more programs that are configured, when executed, to cause one or more processors to execute the method as recited in claim 16.