EP3729134A1

EP3729134A1 - Method for searching for a target object

Info

Publication number: EP3729134A1
Application number: EP18815133.6A
Authority: EP
Inventors: Thomas Gloor
Original assignee: Hilti AG
Current assignee: Hilti AG
Priority date: 2017-12-21
Filing date: 2018-11-29
Publication date: 2020-10-28
Also published as: EP3502742A1; US11592579B2; WO2019120929A1; US20210018633A1

Abstract

Method for searching for a target object (14), which is moved along a path, by means of a measuring device (11), a control device and an operating controller (12) which has a GNSS receiver and can be connected to the measuring device (11) via a communication connection (13).

Description

Method for searching for a target object Technical area

The present invention relates to a method for searching for a target object according to the preamble of claim 1 and to an apparatus for carrying out such a method according to the preamble of claim 11.

PRIOR ART During the tracking of a target object by a measuring device, it may happen that the measuring device loses contact with the target object and can not determine any measuring coordinates in the measuring position of the target object. This situation is also known as the "loess of contact". In order to improve the search of the target object and to reduce the time required for this purpose, various measures are known from the prior art. Active targets may emit a signal that is received by the meter in the event of a "loess of contact". However, active target objects have the disadvantage over passive target objects that they require an energy supply.

Presentation of the invention

The object of the present invention is to develop a method for searching for a passive target object, in which the expenditure on equipment is reduced and no additional components for the search of the passive target object are required.

This object is achieved according to the invention in the method mentioned by the features of independent claim 1. Advantageous developments are specified in the dependent claims. The inventive method for searching a target object, which is moved along a path, by means of a measuring device which has a first reference system, a control device and an operating controller, which has a GNSS receiver with a second reference system and which communicates with the Meter is connectable, includes the steps: ^■ in the event that the measuring device has lost contact with the target object, the current position coordinates of the operating con- troller in the second reference frame are determined by means of the GNSS receiver;

^■ the current position coordinates of the operation controller of the controlled leinrichtung be means of a known transformation function of the second reference system in transformed position coordinates in the first coordinate system is transformed,

^■ From the transformed position coordinates of the operating controller in the first reference system, the control device for the measuring device determines a start orientation, wherein the measuring device is aligned with the operating controller in the start orientation, and

^■ The meter is moved according to a preset routine to search for the target object.

The method according to the invention for searching for a target object has the advantage that an existing GNSS receiver of the operating controller is used to determine a start orientation for the measuring device for searching the passive target object, so that no additional component is required and the expenditure on equipment is reduced. The current position of the operating controller can be used to improve the search for a target object, since the operator in one-man operation moves the target object along the way and carries the operating controller with him. The smaller the distance between the target object and the operating controller, the smaller the deviation between the position of the operating controller and the position of the target object.

When the meter has lost contact with the target object, the controller issues a command to the GNSS receiver to determine current position coordinates of the operator controller in the second frame of reference. The current position coordinates of the operating controller are transformed by the control device by means of a known transformation function from the second reference system into transformed position coordinates in the first reference system. From the transformed position coordinates of the operating controller in the first reference system, the control device determines a start orientation for the measuring device, wherein the measuring device is aligned in the start orientation on the operating controller. Starting from the start orientation, the meter is moved according to a preset routine to search for the target object.

During the movement of the target object along the path to M, M measuring positions of the target object are preferably determined by means of the measuring device i-th measuring coordinates in the first reference frame of the measuring device and in N, N> 2 positions of the operating controller GNSS coordinates of the operating controller in the second reference system are determined by means of the GNSS receiver, the i-th measuring coordinates being transmitted from the measuring device to the control device and the jth GNSS coordinates being transmitted from the GNSS receiver to the control device , The i-th measurement coordinates and the j-th GNSS coordinates are used to determine the transformation function between the second frame of reference and the first frame of reference. The transformation function is necessary to be able to determine the current position of the operating controller in the first reference system.

In a first variant, jth timestamps are assigned to the ith measurement coordinates by the measuring device i-th time stamp and / or the jth GNSS coordinates by the GNSS receiver, and the ith timestamps and / or jth timestamps are applied the control facility. The i-th timestamps and j-th timestamps allow assignment of the measurement coordinates and GNSS coordinates to determine the transformation function between the second frame of reference and the first frame of reference.

In a second variant, the i-th measurement coordinates are assigned by the control device i-th time stamps and / or the j-th GNSS coordinates by the control device j-th timestamp. If the meter and / or the GNSS receiver do not have a timer, the controller may assign the time stamps during transmission.

More preferably, the j-th GNSS coordinates are assigned to the i-th measurement coordinates by the controller when the time difference between the i-th time stamp of the i-th measurement coordinates and the j-th time stamp of the j-th GNSS coordinates is minimum.

More preferably, the j-th GNSS coordinates are assigned to the i-th measurement coordinates by the controller when the time difference between the i-th time stamp of the i-th measurement coordinates and the j-th time stamp of the j-th GNSS coordinates is smaller than a preset maximum Time difference is.

The assignment of i-th measurement coordinates to j-th GNSS coordinates is required in order to be able to determine the transformation function between the second reference system and the first reference system. The correct assignment between the i-th measurement coordinates and the j-th GNSS coordinates is important, above all, for fast-moving target objects in order to reduce inaccuracies.

The control device determines a time difference for the i-th measurement coordinates and j-th GNSS coordinates, respectively, and assigns to the ith measurement coordinates of the target object those j-th GNSS coordinates that have the smallest time difference. The assignment of the ith timestamps to the i-th measurement coordinates and the j-th timestamp to the j-th GNSS Coordinates can already take place during the determination of the i-th measurement coordinates and j-th GNSS coordinates or the time stamps are assigned to the i-th measurement coordinates and j-th GNSS coordinates when being transmitted to the control device by the control device.

A first preferred variant comprises the steps:

^■ the ith measurement coordinates and ith timestamps are determined by the control device as the first data points,

^■ for the first data points, the controller adjusts a first fit curve,

^■ from the first fit curve first approximate coordinates are determined by the control device at first times, the first times corresponding to the jth time stamp of the jth GNSS coordinates, and

^■ the transformation function between the second frame of reference and the first frame of reference is determined by the controller at least partially by means of the first approximate coordinates and the jth GNSS coordinates.

A second preferred variant comprises the steps:

^■ the jth GNSS coordinates and jth timestamps are determined by the control device as second data points,

^■ for the second data points, the controller adjusts a second fit curve,

^■ from the second fit curve th from the controller to the second Zeitpunk- second approximation coordinates are determined, wherein the second points in time corresponding to the i-th time stamps of the i-th measurement coordinates, and

^■ the transformation function between the second frame of reference and the first frame of reference is determined by the controller at least partially by means of the ith measurement coordinates and second approximate coordinates.

A third preferred variant comprises the steps:

^■ the i-th measurement coordinates and ith timestamps are determined by the control device as the first data points, and for the first data points, a first fit curve is adapted by the control device,

^■ the jth GNSS coordinates and jth timestamps are determined by the control device as second data points and for the second data points a second fit curve is adapted by the control device, ^■ The control device determines first approximate coordinates from the first fit curve at predetermined times and second approximate coordinates from the second fit curve, and

^■ the transformation function between the second frame of reference and the first frame of reference is determined by the controller at least partially by means of the first approximate coordinates and second approximate coordinates.

The device for carrying out a method for searching a target object has a measuring device, a control device, an operating controller, which has a GNSS receiver, and a communication link, which connects the measuring device and the operating controller together.

In a first preferred variant, the GNSS receiver is permanently installed in the operating controller. An operator controller with a built-in GNSS receiver requires no additional components to search for a passive target.

In a second preferred variant, the GNSS receiver is connected to the operating controller via a data interface. The ability to connect the GNSS receiver via a data interface allows the use of control panels that do not have built-in GNSS receivers. Each external GNSS receiver, which can be connected to the operating controller via a data interface, supports the search for a passive target object.

embodiments

Exemplary embodiments of the invention are described below with reference to the drawing. This is not necessarily to scale the embodiments, but the drawing, where appropriate for explanation, executed in a schematic and / or slightly distorted form. It should be noted that various modifications and changes may be made in the form and detail of an embodiment without departing from the general spirit of the invention. The general idea of the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, or limited to an object which would be limited in comparison with the subject matter claimed in the claims. For given design ranges, values within the specified limits are also to be disclosed as limit values and to be used and claimed as desired. For simplicity, the same reference numerals are used below for identical or similar parts or parts with identical or similar function.

Show it: FIGS. 1A, B a device with a measuring device, an operating controller and a

A communication link in a three-dimensional representation (FIG. 1A) and in a block diagram (FIG. 1B);

FIGS. 2A, B show an arrangement in which the measuring device has lost contact with a target object and a method according to the invention for searching for a target object is used; and

FIG. 3 shows a scenario in which a transformation function between a second

Reference system of a GNSS receiver and a first frame of reference of the measuring device can be determined.

FIGS. 1A, B show a device 10, which comprises a measuring device 11, an operating controller 12 and a communication link 13, for carrying out a method according to the invention for searching for a target object. FIG. 1 A shows the device in a three-dimensional representation and FIG. 1B shows the structure of the device 10 in a block diagram.

The communication connection 13 connects the measuring device 1 1 and the operating controller 12 with each other and is designed as a wireless communication link. All known technologies for data transfer, such as Bluetooth, radio, WiFi, infrared, etc., are suitable as the wireless communication link. The measuring device 11 is designed as a total station and serves inter alia to track a target object 14; the target object 14 is designed as a passive target object. The measuring device 1 1 comprises a distance measuring unit 15 and an angle measuring unit 16. The target object 14 is fastened to a holding bar 17 and is moved by an operator. On holding rod 17, a receiving element may be attached, which receives the operating controller 12; Alternatively, the operator can hold the operating controller 12 in his hand during the movement of the holding rod 17.

During the tracking of the target object 14 by the measuring device 1 1, it may happen that the measuring device 11 loses contact with the target object 14 and can not determine any measuring coordinates in the measuring position of the target object 14. This situation is also known as the "loess of contact". In order to improve the search for the target object 14 and to reduce the time required for this, the device 10 can execute a method according to the invention for searching the target object 14.

The operating controller 12 comprises a housing 21, a control device 22, which is arranged within the housing 21, a GNSS receiver 23 which is arranged within the housing 21, an operating device 24 and a display device 25. The GNSS receiver 23 is in the embodiment firmly installed in the housing 21, alternatively, the GNSS receiver be designed as an external GNSS receiver and be connected via a data interface 26 of the control panel 12 to the control device 22.

In the exemplary embodiment, the operating device 24 and the display device 25 are designed as separate elements in the form of a keyboard and a display. Alternatively, the operating device 24 and display device 25 can be integrated together in a touchscreen. The operating device 24 and display device 25 are embedded in the housing 21 of the operating controller 12 and fixedly connected to the housing 21, alternatively, the operating device 24, the display device 25 or the operating and display device 24, 25 may be formed as separate elements and be connected to the controller 22 via a data interface (USB, Bluetooth, WiFi).

FIGS. 2A, B schematically show an arrangement in which the measuring device 1 1 has lost contact with the target object 14 and the method according to the invention for searching for a target object is used. FIG. 1A shows the measuring device 1 1 in an orientation in which the target object 14 is located outside a field of view 31 of the measuring device 11; the meter 1 1 has lost contact with the target object 14.

The implementation of the method according to the invention for searching for a target object is controlled by the control device 22 of the operating controller 12. The control device 22 issues a command to the GNSS receiver 23 to determine current position coordinates P _{act of} the operating controller 12 in the second reference system BZ-2 of the GNSS receiver 23. The current position coordinates P _{act of} the operating controller 12 are transformed by the control unit 22 by means of a known transformation function into transformed position coordinates in the first reference system BZ-1 of the measuring device 11. Subsequently, the control device 22 determines from the transformed position coordinates of the operating controller 12 a start orientation 32 for the measuring device 11. In this case, the start orientation 32 corresponds to an orientation of the measuring device 11, in which the measuring device 11 is aligned with the transformed position coordinates of the operating controller 12. The meter 1 1 is moved from the starting orientation 32 in accordance with a preset routine to search the target object 14.

The inventive method for searching for a target object requires that the transformation function between the second reference system BZ-2 and the first reference system BZ-1 is known. FIG. 3 shows a scenario with which the transformation function can be determined. The target 14 is moved by an operator along a path. In several measuring positions of the target object 14, the measuring device 1 acquires measuring coordinates and in several positions of the operating controller 12 GNSS coordinates are acquired by the GNSS receiver 23. The embodiment shows six Measuring positions of the target object 14 and six positions of the operating controller 12. In the general case, the target object 14 is arranged in M different measuring positions MP, i = 1... M, and the operating controller 12 is in N different positions P _j , j = 2 ... N arranged. The numbers M and N may be the same or different. In each measurement position MP sawn correct the meter 11 for the target object 14 i-th measurement coordinates _MK, i = 1 ... M, where the i-th measurement coordinate MK, are recorded in a first reference system BZ-1 of the measuring device 11 , In each position P _j , the GNSS receiver 23 determines j-th GNSS coordinates K _j , j = 1... N for the operating controller 12, the j-th GNSS coordinates K _j in a second reference frame BZ -2 of the GNSS receiver 23 are detected.

In a first variant, the i-th measurement coordinates MK, and i-th time stamp t are determined by the control device 22 as the first data points. For the first data points, the control device 22 adapts a first fit curve, wherein known fit curves can be used. The control device 22 determines to first time xi _k points from the first fit curve first approximate coordinates, wherein the first time points c _j corresponding to the j-th time stamps T of the jth GNSS coordinates K _j. The control device 22 determines the transformation function between the second reference system BZ-2 of the GNSS receiver 23 and the first reference system BZ-1 of the measuring device 1 1 using the first approximate coordinates and the j-th GNSS coordinates Kj.

In a second variant, the jth GNSS coordinates K _j and j th time stamp T _{j are determined} by the control device 22 as second data points. For the second data points, the control device 22 adapts a second fit curve, wherein known fit curves can be used. The control device 22 determines second approximation coordinates from the second fit curve at second times x _2k , the second times x _2k corresponding to the ith time stamp t, the ith measurement coordinates. The control device 22 determines the transformation function between the second reference system BZ-2 of the GNSS receiver 23 and the first reference system BZ-1 of the measuring device 1 1 using the ith measuring coordinates MK, and the second approximate coordinates.

In a third variant, the i-th measurement coordinates MK, and i-th time stamp t are determined by the control device 22 as first data points, and for the first data points, a first fit curve is adapted by the control device 22. The j-th GNSS coordinates P _j and j-th time stamps T _j are determined by the control device 22 as second data points, and for the second data points, a second fit curve is adapted by the control device 22. The control device 22 determines, at predetermined times X _k, first approximate coordinates from the first fit curve and second approximation coordinates from the second fit curve. The control device 22 determines the transformation function between the second reference frame BZ-2 of the GNSS receiver 23 and the first one Reference frame BZ-1 of the measuring device 1 1 using the first approximate coordinates and second approximate coordinates.

Claims

claims

Method for searching a target object (14), which is moved along a path, by means of a measuring device (11) having a first reference system (BZ-1), a control device (22) and an operating controller (12) , which has a GNSS receiver (23) with a second reference system (BZ-2) and which can be connected to the measuring device (11) via a communication connection (13), with the steps:

^■ in the event that the measuring device (11) has lost contact with the target object (14), current position coordinates of the operating controller (12) in the second reference frame (BZ-2) are determined by means of the GNSS receiver (23),

^■ the current position coordinates of the operator controller (12) of the control device (22) is transformed into transformed position coordinates (BZ-1) in the first coordinate system using a known transformation function of the second reference system (BZ-2),

^■ From the transformed position coordinates of the operating controller (12) in the first reference system of the control device (22) for the measuring device (11) determines a start orientation (32), wherein the measuring device (11) in the start orientation (32) on the operating controller (12 ), and

^■ the meter (11) is moved in accordance with a preset routine for searching the target object (14).

2. The method according to claim 1, characterized in that during the movement of the target object (14) along the path in M, M> 2 measuring positions (MP ,, i = 1 ... M) of the target object (14) by means of the measuring device ( 11) i-th measuring coordinates (MK ,, i = 1 ... M) in the first reference system (BZ-1) of the measuring device (1 1) are determined and in N, N> 2 positions (P _j , j = 1 ... N) of the operating controller (12) by means of the GNSS receiver (23) j-th GNSS coordinates (K _j , j = 1 ... N) of the operating controller (12) in the second reference frame (BZ-2) of the GNSS receiver (23), the i-th measuring coordinates (MKi) from the measuring device (11) to the control device (22) and the jth GNSS coordinates (K _j ) from the GNSS receiver (23). be transmitted to the control device (22).

3. The method according to claim 2, characterized in that the i-th measuring coordinates (MKi, i = 1 ... M) from the measuring device (11) i-th time stamp (t, i = 1 ... M) and the j GNSS coordinates (K _j , j = 1 ... N) from the GNSS receiver (23) j-th timestamp (T _j , j = 1 ... N) are assigned and the ith timestamps (t ) and j-th time stamps (T _j ) are transmitted to the control device (22).

4. The method according to claim 2, characterized in that the i-th measuring coordinates (MKi, i = 1 ... M) from the control device (22) i-th time stamp (t, i = 1 ... M) and the Jth GNSS coordinates (K _j , j = 1 ... N) from the control device (22) j-th timestamps (T _j , j = 1 ... N) are assigned.

5. The method according to any one of claims 3 to 4, characterized in that i-th measuring coordinates (MKi) from the control device (22) j-th GNSS coordinates (K _j ) are assigned when the time difference (At _j ) between the i-th time stamp (t) of the i-th measurement coordinates (MKi) and the j-th time stamp (T _j ) of the j-th GNSS coordinates (K _j ) is minimal.

6. The method according to claim 5, characterized in that i-th measuring coordinates (MK) from the control device (22) j-th GNSS coordinates (K _j ) are assigned when the time difference (At, _j ) between the ith Time stamp (t,) of the i-th measurement coordinates (MK) and the j-th time stamp (T _j ) of the j-th GNSS coordinates (K _j ) is smaller than a preset maximum time difference (A).

7. The method according to any one of claims 5 to 6, characterized in that the transformation function between the second reference system (BZ-2) and the first reference system (BZ-1) of the control device (22) at least partially by means of i -th measurement coordinates (MK, i = 1 ... M) and the j-th GNSS coordinates (K _j , j = 1 ... N) is determined.

8. The method according to any one of claims 3 to 4 with the steps:

the i-th measurement coordinates (MK, i = 1... M) and i-th time stamps (fc, i = 1... M) are determined by the control device (22) as the first data points, for the first data points of the control device (22) adapted a first fitness curve,

^■ from the control device (22) first approximate coordinates are determined from the first fit curve at first times (tik), wherein the first times (xi _k ) the j-th time stamps (T _j , j = 1 ... N) of j-th GNSS coordinates (K, j = 1 ... N), and

^■ the transformation function between the second reference system (BZ-2) and the first reference system (BZ-1) from the control means (22) at least partially (by means of the first approximate coordinate and the j-th GNSS coordinates K _j, j =. 1 .. N) determined.

9. The method according to any one of claims 3 to 4 with the steps: ^■ the j-th GNSS coordinates (K _j , j = 1 ... N) and j-th time stamps (T _j , j = 1 ... N) are determined by the control device (22) as second data points,

^■ for the second data points, the control device (22) adjusts a second fit curve,

^■ the control device (22) from the second fit curve to second points in time (x _2k) second approximate coordinates determined, wherein the second Zeitpunk- te (i2 _k) denotes the i-th time stamp (t) corresponding to the i-th measurement coordinate , and

^■ the transformation function between the second reference system (BZ-2) and the first reference system (BZ-1) from the control means (22) at least partially by means of the i-th measurement coordinate (MK ,, i = 1 ... M) and second Proximity coordinates determined.

10. The method according to any one of claims 3 to 4 with the steps:

^■ the i-th measurement coordinates (MK ,, i = 1 ... M) and ith timestamps (fc, i = 1 ... M) are determined by the control device (22) as first data points and for the first data points is adapted by the control device (22) a first fit curve,

^■ the j-th GNSS coordinates (P _j , j = 1 ... N) and j-th timestamps (T _j , j = 1 ... N) are determined by the controller (22) as second data points and for the second data points are adapted by the control device (22) a second fit curve,

^{■ are determined} by the control device (22) at predetermined times (x _k ) from the first fit curve first approximate coordinates and from the second fit curve second approximate coordinates and

^■ The transformation function between the second reference system (BZ-2) and the first reference system (BZ-1) of the measuring device (11) is determined by the control device (22) at least partially by means of the first approximate coordinates and second approximate coordinates.

1 1. Apparatus for carrying out a method for searching a target object (14) according to one of claims 1 to 10, comprising a measuring device (11), a control device

(22), an operation controller (12) having a GNSS receiver (23), and a communication link (13) connecting the measuring device (1 1) and the operation controller (12) with each other.

12. The device according to claim 1 1, characterized in that the GNSS receiver

(23) is permanently installed in the operating controller (12).

13. The device according to claim 11, characterized in that the GNSS receiver (23) via a data interface (26) with the operating controller (12) is connected.