Patent Application
20250216197
The present application claims priority to European Patent Application No. 23315491.3, filed Dec. 27, 2023 and European Patent Application No. 24211455.1, filed Nov. 7, 2024, the entire contents of which are incorporated herein by references for all purposes.
The present disclosure relates to a surveying pole, to a method implemented in a surveying pole, and to a top unit for a surveying pole. More specifically, it relates to determining a length of a pole arrangement of the surveying pole.
Surveying involves the determination of three-dimensional positions of points to map and create a model of the terrain or structure being surveyed. For this purpose, surveying poles having a target and/or other piece of surveying equipment, such as a GNSS (Global Navigation Satellite System) antenna, may be used. In use, a surveying pole is placed in contact with a measurement point. A surveying pole with a target is typically used in cooperation with a geodetic instrument, such as a geodetic scanner, a theodolite or a total station, to determine a distance and angle between the measurement point and the known position of the geodetic instrument. A surveying pole with a GNSS antenna may obtain its own position from signals received by satellites of the GNSS system. Thus, the position of the target and/or the GNSS antenna is obtained. For determination of the position of the measurement point, it is necessary to know the height of the target/antenna above the measurement point. For this purpose, an accurate measurement of the length of the surveying pole is needed. At the same time, it is always desirable to improve the ease of handling, both during operation and transport, of the surveying pole, in particular by minimizing the dimensions and weight of the surveying pole.
In view of the above, an object of the present disclosure is to provide an improved surveying pole, enabling improved (e.g., accurate or at least more accurate) measurement of a length of the surveying pole, while reducing a weight of the same.
The invention is defined by the appended claims, with embodiments being set forth in the appended dependent claims, in the following description, and in the drawings.
According to a first aspect of the inventive concept, there is provided a surveying pole comprising a pole arrangement extending along a longitudinal axis between a first end and a second end. The pole arrangement comprises at least a first pole section and a second pole section telescopically arranged to provide length adjustment of said surveying pole.
The surveying pole further comprises a target, a top unit, and a processor. The target is internally arranged in the pole arrangement at a predetermined distance from the first end. The top unit is mounted on the pole arrangement at the second end and extends along the longitudinal axis. The top unit comprises a positioning device, an electronic distance measurement (EDM) unit, and an optical arrangement. The electronic distance measurement (EDM) unit is configured to determine a distance to said target, wherein said EDM unit is arranged offset with respect to the longitudinal axis such that at least a portion of a light path between the EDM unit and the target does not coincide with the longitudinal axis within the top unit. The optical arrangement is arranged between the EDM unit and the second end of the pole arrangement, and the optical arrangement is adapted to redirect the light path such that it is parallel with the longitudinal axis within the pole arrangement. The processor is configured to determine a length of the pole arrangement based on the distance determined by the EDM unit.
According to a second aspect of the invention, there is provided a method implemented in a surveying pole. The surveying pole comprises a pole arrangement extending along a longitudinal axis between a first end and a second end. The pole arrangement comprises at least a first pole section and a second pole section telescopically arranged to provide length adjustment of the surveying pole. The surveying pole further comprises a target internally arranged in the pole arrangement at a predetermined distance from the first end and a top unit mounted on the pole arrangement at the second end.
The method comprises:
According to a third aspect of the inventive concept, there is provided a surveying pole comprising a pole arrangement extending along a longitudinal axis between a first end and a second end.
The surveying pole further comprises a target, a top unit, and a processor. The target is internally arranged in the pole arrangement at a predetermined distance from the first end. The top unit is mounted on the pole arrangement at the second end and extends along the longitudinal axis. The top unit comprises a positioning device, an electronic distance measurement (EDM) unit, and an optical arrangement. The electronic distance measurement (EDM) unit is configured to determine a distance to said target, wherein said EDM unit is arranged offset with respect to the longitudinal axis such that at least a portion of a light path between the EDM unit and the target does not coincide with the longitudinal axis within the top unit. The optical arrangement is arranged between the EDM unit and the second end of the pole arrangement, and the optical arrangement is adapted to redirect the light path such that it is parallel with the longitudinal axis within the pole arrangement. The processor is configured to determine a length of the pole arrangement based on the distance determined by the EDM unit.
The pole arrangement of the surveying pole of the third aspect may comprise at least a first pole section and a second pole section telescopically arranged to provide length adjustment of said surveying pole.
Alternatively, the surveying pole of the third aspect may comprise a pole arrangement of a fixed length. In other words, the length of the pole arrangement of the surveying pole of the third aspect may be non-adjustable.
According to a fourth aspect of the invention, there is provided a method implemented in a surveying pole. The surveying pole comprises a pole arrangement extending along a longitudinal axis between a first end and a second end. The surveying pole further comprises a target internally arranged in the pole arrangement at a predetermined distance from the first end and a top unit mounted on the pole arrangement at the second end.
The method comprises:
The pole arrangement of the surveying pole of the fourth aspect may comprise at least a first pole section and a second pole section telescopically arranged to provide length adjustment of said surveying pole.
Alternatively, the surveying pole of the fourth aspect may comprise a pole arrangement of a fixed length. In other words, the length of the pole arrangement of the surveying pole of the fourth aspect may be non-adjustable.
According to a fifth aspect of the inventive concept, there is provided a top unit for a surveying pole. The top unit is configured to be mountable on a pole arrangement extending along a longitudinal axis between a first end and a second end. The pole arrangement comprises a target internally arranged therein at a predetermined distance from the first end. The top unit is further configured to be mountable on the pole arrangement at the second end and to extend along the longitudinal axis when mounted on the pole arrangement.
The top unit comprises a positioning device, an electronic distance measurement (EDM) unit, an optical arrangement, and a processor. The EDM unit is configured to determine a distance to said target, wherein said EDM unit is arranged offset with respect to the longitudinal axis such that at least a portion of a light path between the EDM unit and the target does not coincide with the longitudinal axis within the top unit. The optical arrangement is arranged to be located between the EDM unit and the second end of the pole arrangement when the top unit is mounted on the pole arrangement. The optical arrangement is adapted to redirect the light path such that it is parallel with the longitudinal axis within the pole arrangement. The processor is configured to determine a length of the pole arrangement based on the distance determined by the EDM unit.
The top unit according to the fifth aspect may be detachably mountable on the pole arrangement.
The processor may be arranged within the top unit. The processor may alternatively be external to the top unit.
The top unit according to the fifth aspect and a pole arrangement on which the top unit is mounted may together be referred to as a surveying pole.
The top unit according to the fifth aspect may be mountable to a pole arrangement comprising at least a first pole section and a second pole section telescopically arranged to provide length adjustment to the surveying pole.
The top unit according to the fifth aspect may be mountable to a pole arrangement of a fixed length. In other words, the top unit may be mountable to a pole arrangement of non-adjustable length.
The method according to the second aspect may suitably be implemented in a surveying pole according to the first aspect. The method according to the fourth aspect may suitably be implemented in a surveying pole according to the first aspect. Accordingly, any advantage described herein in connection to an embodiment of the surveying pole applies equally to the surveying pole of the first aspect and to the method of the second aspect, when implemented in such a surveying pole. Additionally, any advantage described herein in connection to an embodiment of the surveying pole applies equally, as far as is compatible, to the surveying pole of the third aspect and to the method of the fourth aspect. Additionally, any advantage described herein in connection to an embodiment of the surveying pole applies equally, as far as is compatible, to the top unit of the fifth aspect.
The present inventive concept provides the benefit that an offset position of the EDM unit with respect to the longitudinal axis allows other components present inside the top unit to be arranged closer to the center axis. The center axis of the top unit may coincide with the longitudinal axis.
Accordingly, by the present inventive concept, the diameter of the top unit may be reduced, compared to a top unit in which the EDM unit is arranged centred with respect to the longitudinal axis. The reduced dimension is advantageous in terms of storage and transport of the surveying pole. As a consequence of the reduced diameter, the weight of the top unit may also be reduced, which is advantageous to the operator of the surveying pole. A further advantage of the reduced weight is to make the top unit more resistant to falls. A higher weight leads to higher energy impact in case of a fall. The potential damage to the top unit and to the components within the top unit in case of a fall is thus reduced by the present inventive concept.
By the present inventive concept, the EDM unit may be arranged within the top unit without increasing the longitudinal dimension, or height, of the top unit. It should be noted that although arranging the EDM unit in line with the center axis and arranging other components within the top unit entirely or partly above the EDM unit would also result in a reduced diameter of the top unit, this would in turn result in a significantly increased longitudinal dimension of the top unit. This may not be desirable, as there may be practical limitations on the longitudinal dimension of the top unit. For example, it may be desirable to allow the top unit to be transported in a case of a particular size.
Yet another advantage of the present inventive concept is that by arranging the EDM unit within the top unit, a conventional, hollow surveying pole arrangement may be used, at least without heavy modification.
In at least one example embodiment, optical arrangement may be adapted to redirect the light path such that it coincides with the longitudinal axis within the pole arrangement.
The positioning device may comprise a reflective element, a light emitting element, and/or a GNSS (Global Navigation Satellite System) antenna, or any combination thereof. The positioning device may be configured to passively cooperate with a geodetic instrument, such as for example a theodolite or a total station. It may be configured to actively cooperate with a geodetic instrument, for example for tracking purposes.
The top unit may comprise further elements, such as tilt sensor, e.g., for determining a tilt angle between the longitudinal axis and the vertical direction.
The top unit may comprise a communication device, e.g., for transmitting the determined length of the pole arrangement to an external unit or instrument. Alternatively, a distance between a point of contact of the surveying pole with the terrain and the positioning device may be calculated based on the determined length and on fixed distances of the surveying pole, such as the distance between the point of contact with the terrain and the target, and the distance between the EDM unit and the positioning device. For example, the determined length, or calculated distance, may be transmitted to a geodetic instrument with which the surveying pole is cooperating. Alternatively, the determined length, or calculated distance, may be transmitted to a separate, optionally mobile, control unit.
The optical arrangement may comprise at least one optical element selected from a group comprising a prism, a mirror, a light guide, and combinations thereof.
A light guide may, for example, comprise optical fibre. In principle, any optical element, or combination of optical elements, adapted to guide light and thus provide the desired light path within the pole arrangement may be used.
This provides freedom for the arrangement of the EDM unit within the top unit.
Said prism may be a triangular prism. For example, said prism may be a right angle prism. Alternatively, said prism may be a rhomboid prism, or a pentaprism.
In at least one example embodiment, the optical arrangement may comprise two prisms. Alternatively, the optical arrangement may comprise two mirrors, or one prism and one mirror.
For example, the optical arrangement may comprise two triangular prisms, or one triangular prism and one mirror.
Prisms have the advantage of being more resistant than mirrors. In particular, prisms may be less prone to damage in case of impact to the top unit, for example due to a fall, or to an external object. A prism also provides better light transmission than a mirror. A mirror may be cheaper to produce than a prism. A mirror may also be significantly lighter than a prism.
The light may be emitted along the light path by a laser of the EDM unit.
The EDM unit may be displaceable to enable adjustment of the light path in the pole arrangement.
The optical arrangement may comprise at least one displaceable element to enable adjustment of the light path in the pole arrangement.
Thus, the light path in the pole arrangement may be adjusted by displacement of the EDM unit and/or displacement of at least one element of the optical arrangement.
This enables calibration of the EDM unit. This is advantageous as it allows the EDM unit to be calibrated in a late stage of the manufacturing or assembly of the top unit. It may reduce the precision with which the EDM unit must be mounted within the top unit, and thereby make the manufacturing or assembly of the top unit less complicated and/or less costly. The desired precision of the instrument can then be obtained in a calibration step. For this purpose, the top unit may be arranged on a calibration bench, and the position of the EDM unit and/or the position of a displaceable element of the optical arrangement may be adjusted to obtain the desired light path for the light emitted by the EDM unit.
An advantage with effecting the adjustment by displacement of an element of the optical arrangement is that it is less bulky. In other words, a displaceable element of the optical arrangement is typically smaller than the EDM unit. Displacing such an element therefore requires less space than displacing the EDM unit. Furthermore, when the adjustment is made by displacement of an element of the optical arrangement, the adjustment system must carry less weight than if it carried the EDM unit. This may make the system more durable.
The optical arrangement may comprise at least one fixed prism having one surface which, when the top unit is mounted on the pole arrangement, faces the interior of the pole arrangement.
Thereby, the light emitted by the EDM unit may exit (or enter, after being reflected by the target) the top unit directly through the at least one prism. In other words, no further optical element, such as an optical window, is needed to allow the light to exit (or enter) the top unit.
In such an optical arrangement, the at least one fixed prism may be sealingly fixed to the top unit to provide a seal between the interior of the top unit and the interior of the pole arrangement.
Thereby, a protected environment for the components present in the top unit may be created. That is, the light emitted by the EDM unit/reflected by the target is allowed to exit/enter the top unit, while preventing contamination of the interior of the top unit by, for example, dust or other particles.
The top unit may be detachably mounted, or detachably mountable, on the pole arrangement.
This may allow the top unit to be used with different pole arrangements. In particular, such a top unit may easily be transferred between different pole arrangements, depending on the needs of the current application. For example, such a top unit may be mounted on pole arrangements of different heights or lengths, stiffness, or other characteristics. Should the pole arrangement be damaged, a detachably mounted top unit may be easily switched to a working pole arrangement.
Thus, the top unit may be used with different fixed-length pole arrangements. Although the length of such a fixed-length pole arrangement may, in some cases, be known, the present inventive concept provides the advantage that the length of the pole arrangement can be automatically obtained. In other words, a nominal length of the pole arrangement can automatically be verified.
The top unit may comprise a battery for powering said positioning device and said EDM unit. The battery may further power other components present in the top unit. Thus, the top unit, or the components therein, may not need to be powered by an external source of power. In particular, no external power source is needed on or within the pole arrangement.
Aspects of the present inventive concept, including its particular features and further advantages, will now be described with reference to the drawings, in which:
A typical scene of a surveying pole 1 according to the present inventive concept in use is illustrated in
The surveying pole 1 comprises a pole arrangement 100 extending along a longitudinal axis A between a first end 101 and a second end 102. As illustrated, the pole arrangement 100 comprises a first pole section 105 and a second pole section 106 telescopically arranged to provide length adjustment of the surveying pole 1. A target 111 (not visible in
Although the figures show a telescopic pole arrangement, the pole arrangement may also be a pole arrangement of fixed length. In other words, the length of the pole arrangement may be non-adjustable. The top unit may thus be used with interchangeable pole arrangements having different fixed lengths, or different adjustable lengths.
A top unit 104 is mounted on the pole arrangement 100 at the second end 102 and extends along the longitudinal axis A. The top unit 104 comprises a positioning device 107, which positioning device may comprise reflective elements 108, light emitting elements 109, and/or a GNSS (Global Navigation Satellite System) antenna 110.
The top unit 104 further comprises an electronic distance measurement (EDM) unit 112 (not visible in
The top unit 104 further comprises and optical arrangement 200 (not visible in
The surveying pole 1 further comprises a processor 115 configured to determine the length of the pole arrangement 100 based on the distance determined by the EDM unit 112. In the present example, the processor 115 is illustrated as being arranged within the top unit 104.
A pointing tip 103 is mounted at the first end 101 of the pole arrangement 100. In use of the surveying pole 1, when making a measurement on a point of interest 10 on the terrain or on a structure, the pointing tip 103 is placed on the point of interest 10. Typically, the surveying pole 1 is held in a vertical position during a measurement. Accordingly, the pointing tip 103 is the lowest part of the surveying pole 1 while in use, whereas the top unit 104 is at the highest part of the surveying pole 1. In the following, when referring to the surveying pole 1, parts thereof and/or elements comprised therein, expressions such as above, higher, below, lower, etc., should be interpreted as referring to the surveying pole 1 when in a typical in-use position, as described above. More precisely, such expressions should be interpreted so that, when the surveying pole 1 is in use, an element which is above or higher than another element is closer to the sky along the longitudinal axis A than that element; conversely, an element which is below or lower than another element is closer to the point of interest 10 along the longitudinal axis A than that element.
A first step in determining the position of the point of interest 10 is to determine the position of the positioning device 107.
In the example of
The point of reference 11 may have a known position, e.g., in a common reference frame. In order to determine the position of the point of interest 10 in relation to the point of reference 11, the EDM unit of the center unit 120 may for example measure the distance between the positioning device 107 of the surveying pole 1 and the total station 117 based on light emitted towards the positioning device 107 by the EDM unit and reflected back towards the total station 117 by a reflective element 108 of the positioning device 107. The position of the positioning device 107 may then be derived based on the measured distance and the orientation of the sighting axis 121.
Alternatively, or additionally, the GNSS antenna 110, or receiver, may receive positioning data from a GNSS, illustrated by a plurality of satellites 116.
Knowing the position of the positioning device 107, the position of the point of interest may then be derived based on the distance between the positioning device and the point of interest 10, i.e. the distance between the positioning device 107 and (the tip of) the pointing tip 103. For this purpose, an accurate measurement of the length of the pole arrangement 100 of the surveying pole 1 is needed. Such a measure is provided by the surveying pole 1 according to the present inventive concept, as will be explained in further detail below.
It should be noted that in the scene depicted in
There may be situations in which a measurement of a point of interest is needed where there is an obstacle between the total station 117 and the positioning device 107. Adjusting the length of the surveying pole 1 to move the positioning device 107 higher up may then provide a direct line of sight between the total station 117 and the positioning device 107. Conversely, adjusting the length of the surveying pole 1 to a shorter length may be desirable, for example, if an object above the point of interest (a branch of a tree, or part of a structure such as a roof, for instance) is preventing the surveying pole from being positioned on the point of interest. In general, a surveying pole 1 having an adjustable length provides improved flexibility in terms of positioning, and improved handling for the operator of the surveying pole 1.
As mentioned above, the top unit 104 may also be mounted on pole arrangements of a fixed length. Thus, an operator may choose a pole arrangement of an appropriate length for a particular application. For example, a longer pole arrangement may be chosen to provide a direct line of sight between the total station 117 and the positioning device 107 above an obstacle, or a shorter pole arrangement may be chosen to allow operation under an overhanging object or structure.
The pole arrangement 100 of the surveying pole 1 is schematically shown in greater detail in
Shown in
The respective pole sections 105, 106 may be made of aluminium, which offers a good balance between stiffness, weight, and ease of manufacturing.
The second pole section 106 is here illustrated as being double walled, i.e., the second pole section 106 comprises an outer tube 123 and an inner tube 124. The second pole section 106 may be manufactured as a single component, for example by extrusion.
A ring 122 is mounted at the lower end of the second pole section 106.
As illustrated in
A pointing tip 103, for placing in contact with the point of interest to be measured, is mounted at the first end 101 of the first pole section 105.
In the present example, the target 111 is arranged in the first pole section 105, near the first end 101 and above the pointing tip 103. Different placements of the target 111 are possible, as long as the placement of the target 111 does not prevent length adjustment of the surveying pole (i.e. it does not impede the telescopic displacement of the second pole section 106) and as long as the distance between the target 111 and the first end 101 does not vary when adjusting the length of the surveying pole. The target 111 is positioned at a distance 126, in the longitudinal direction, from the first end 101 and thus at a distance from (the tip of) the pointing tip 103. The distance 126 may for example be 5 cm to 45 cm, or 10 cm to 40 cm, or 15 cm to 35 cm. In particular, the distance 126 may be 30 cm. This may ensure that the target is above water level during measurement in most cases.
The light path 114, within the pole arrangement 100, between the EDM unit 112 and the target 111 is also shown in
The top unit 104 may be mounted on the pole arrangement 100 by any suitable fastening means, for example comprising screws, bolts, threads, etc (not shown in the figure). In particular, the top unit 104 may be detachably mounted on the pole arrangement.
In embodiments where the pole arrangement has a fixed length (not illustrated in the figures), the pole arrangement may have similar characteristics as the pole arrangement described above, except for the length adjustment capability.
The schematic illustration of
The top unit 104 shown in
The top unit 104 is mounted on the pole arrangement 100. In
As is clearly shown in
In the present example, the optical arrangement 200 comprises a first 201 and a second 202 right-angle, triangular prism. Thus, light emitted by the EDM unit 112 first enters the first prism 201, whereby the light path 114 is redirected towards the second prism 202, which in turn redirects the light path 114 such that it is parallel with the longitudinal axis A within the pole arrangement 100.
The second prism 202 is fixed within the top unit 104. The second prism 202 is further arranged with a surface 204 which, when the top unit 104 is mounted on the pole arrangement 100, faces the interior of the pole arrangement 100. In other words, the second prism 202 provides an exit from, an entrance to, the top unit 104 for the light path 114. Furthermore, the second prism 202 is sealingly fixed to the top unit 104 to provide a seal between the interior of the top unit 104 and the interior of the pole arrangement 100. In particular, the seal is provided by a ring 203.
Adjustment of the light path 114 is provided by displacement of the first prism 201. In particular, the first prism 201 may be mounted on a support structure 204, the orientation of which is adjustable. For example, the orientation of the support structure 204 may be adjustable by means of adjustment screws 205. In an alternative not shown in the figures, adjustment of the light path 114 may instead be provided by displacement of the EDM unit.
With reference to
The optical arrangement 200 may, instead of two prisms 201, 202 comprise two mirrors 206, 207, as shown in
A further alternative arrangement of the optical arrangement 200 is shown in
Yet another alternative arrangement is shown in
As apparent in the figures and described above, the EDM unit is arranged offset with respect to the longitudinal axis A. Note that the EDM 112 unit may be arranged such that a portion 113 of the light path 114 within the top unit 104 is not parallel with the longitudinal axis A, such as for example in the configurations of
Further alternatives of the optical arrangement 200 are possible, although not shown in the figures. For example, a pentaprism may be used. More generally, the optical arrangement 200 may comprise any type of light guide. For example, optical fibre may also be used to guide the light path 114 within the top unit 104.
It is envisioned that, no matter which configuration is chosen for the optical arrangement, adjusting the light path 114 is performed as a calibration operation, either as a step during manufacturing/assembly of the top unit 104, or during a service of the surveying pole. Adjusting the light path 114, for example by manipulating adjustment screws as described above, is thus done by trained personnel in a controlled environment.
With reference to
At step 501, the EDM unit 112 emits a light beam along a first portion 113 of a light path 114, such that the first portion 113 does not coincide with the longitudinal axis A.
At step 502, the optical arrangement 200 redirects the light path 114 such that it is parallel with the longitudinal axis A within the pole arrangement.
The light beam reaches the target 111 and is subsequently reflected back toward the EDM unit 112 along the light path 114.
At step 503, the EDM unit 112 determines the distance between the EDM unit 112 and the target 111, for example based on the travel time of the light beam emitted by the EDM unit 112.
At step 504, the processor 115 determines a length of the pole arrangement 100 based on the distance between the EDM unit 112 and the target 111 determined by the EDM unit 112.
In an optional step 505, the determined length of the pole arrangement 100, or a distance between the pointing tip 103 and the positioning device 107 derived therefrom, is transmitted to an external unit or instrument, such as for example an optionally mobile control unit, or a total station 117 cooperating with the surveying pole 1.
The method could also be summarized as having a step of determining, with the EDM unit 112, the distance between the EDM unit 112 and the target 111, wherein the EDM unit 112 is arranged offset with respect to the longitudinal axis A in the top unit 104 such that at least a portion 113 of a light path 114 between the EDM unit 104 and the target 111 does not coincide with the longitudinal axis A within the top unit 104. For this purpose, the method also comprises a step of redirecting the light path 114 such that it is parallel with the longitudinal axis A within the pole arrangement 100. The method further comprises a step of determining, in particular by the processor 115, a length of the pole arrangement based on the distance determined by the EDM unit 112.
Although features and elements are described above in particular combinations, each feature or element may be used alone without the other features and elements, or in various combinations with or without other features and elements.
Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements, and the indefinite article “a” or “an” does not exclude a plurality.
Item 11. The surveying pole according to any one of the preceding items, wherein said top unit comprises a battery for powering said positioning device and said EDM unit. 30
| Number | Date | Country | Kind |
|---|---|---|---|
| 23315491.3 | Dec 2023 | EP | regional |
| 24211455.1 | Nov 2024 | EP | regional |
