WO2018114669A1

WO2018114669A1 - Measuring system for detecting the thickness of layers

Info

Publication number: WO2018114669A1
Application number: PCT/EP2017/083026
Authority: WO
Inventors: Marcus Watermann; Dominik Becher
Original assignee: Moba Mobile Automation Ag
Priority date: 2016-12-19
Filing date: 2017-12-15
Publication date: 2018-06-28
Also published as: DE102016225502B4; DE102016225502A1

Abstract

The invention relates to a measuring system for detecting the thickness of layers for a paving machine with a screed, comprising a laser source, a laser detector, and a computing device. The laser source emits a laser beam towards the laser detector, and the laser detector is designed to detect the position of the laser beam over a region along a vertical axis. One of two units, i.e. the laser detector and the laser source, is connected to a chassis of the paving machine or a reference sensor of the paving machine such that the first unit is guided at a defined height to the underlying surface for the layer to be assembled while the second of the two units is connected to the screed which lies on the layer to be assembled such that the second unit is moved along the vertical axis on the basis of the layer thickness. The computing device is designed to determine the layer thickness on the basis of the position of the laser beam along the vertical axis.

Description

Measuring system for coating thickness detection

description

Embodiments of the present invention relate to a measuring system for detecting layer thickness and a corresponding method and computer program. The present invention is generally in the field of road finishers, in particular a paver with a layer thickness detection device. A preferred embodiment relates to an apparatus and a method for detecting the thickness of a built-in by such a paver on a substrate material layer. In general, a paver with a chassis consisting of caterpillars or wheels runs on a prepared surface on which a road surface to be produced or a road surface to be produced is applied. As a rule, the built-in road surface is a bituminous material, but also sandy or stony layers or concrete layers can be installed. In the direction of travel behind the paver a height-adjustable screed is provided at the front of a stockpile of the paving material is piled up, which is promoted and distributed by a conveyor, which ensures that on the front of the screed always a sufficient, but not too large amount the paving material is kept stockpiled. The height of the trailing edge of the screed opposite the surface of the prepared ground, which may optionally also be formed by an old pavement, defines the thickness of the finished pavement before its subsequent further consolidation by rolling. The screed is held on a pulling arm, which is rotatably mounted about a arranged in the center region of the paver traction point, the altitude of the screed is set by a hydraulic adjustment.

When building a road, it is desirable to measure the generated layer as continuously as possible and in real time. The determination of the layer thickness is desired, for example, to control the quality of the newly installed road surface. If the calculated layer thickness, for example a bituminous layer, too low, then there is a risk that the road surface breaks early, resulting in costly rework of the Road pavement has the consequence. On the other hand, the layer thickness should be checked with regard to the amount of material used in order not to obstruct too much material, which would lead to increased costs. EP 2 921 588 A1 and EP 3 048 199 A1 disclose road pavers with a screed for installing a material layer on a substrate and a layer thickness detection device for detecting the thickness of the incorporated material layer. The layer thickness detection device comprises a first sensor in the direction of travel behind the screed for detecting a first distance to the built-in material layer and a second sensor in the direction of travel in front of the screed for detecting a second distance to the ground.

Further known systems for determining the layer thickness of a newly installed road surface are described, for example, in EP 2 535 458 A1, EP 2 535 457 A1 or EP 2 535 458 A1.

Furthermore, from DE 100 60 903 A1 a laser control device for a construction machine for adjusting the height of a height-adjustable machining tool with a first, second and third laser measuring head is known, wherein the control device is arranged on the construction machine and the measuring points of the laser measuring heads on a reference surface from each other are spaced apart and lie substantially in the direction of movement of the construction machine one behind the other. The first and second laser measuring heads are at a first angle and the first and third laser measuring heads are at a second angle to each other. An evaluation determines depending on the output signals of the first, second and third laser measuring their distances from the reference surface and calculated due to the specific distances and the known geometric arrangement of the laser measuring heads with respect to the machining tool, the height of the machining tool relative to the reference plane. Depending on the calculated height and a desired height, the evaluation device generates a height control signal for the machining tool.

Known from DE 10 2009 044 581 A1 are methods of asphalting a surface to a desired height using a paver laying a bituminous mat of controlled thickness on a foundation plane and compacting the asphalt to the desired height using a compacting machine. In this case, the scanning of the contour line of the foundation plane can be carried out using a laser ablation. tasting device done. To determine the height of the top of the asphalt mat after compression can be done with a laser scanner, which is directed to the surface behind the compacting machine. Therefore, there is a need for an improved approach.

The object of the present invention is to provide a layer thickness detection concept which provides an improved compromise of reliable and accurate measurement function, flexibility and functionality. The object is solved by the independent claims.

Exemplary embodiments of the present invention provide a measuring system for measuring layer thickness for a paver with a screed. The measuring system includes a laser detector and a laser source. The laser source is arranged to emit a laser beam to the laser detector. The laser detector is designed to detect a position (ie the impact height) of a laser beam within a local area along an elevation axis, whereby a height change can be determined in the first place. The measuring system further comprises a calculation unit which performs the evaluation of the position of the laser beam. Since a first of the two units of laser detector and laser source is connected to a chassis of the paver or a reference paver of the paver, this first unit is guided at a defined, previously known height to the substrate for the layer to be installed. The corresponding second unit of the two units is connected to the screed, which rests on the layer to be installed, so that the second unit is moved to the layer in a defined (previously known) height depending on the layer thickness along the height axis. Thus, based on the determined position of the laser beam along the height axis / impact height, the layer thickness (and also a layer thickness change) can be detected. According to exemplary embodiments, the layer thickness can be calculated by forming a difference between the defined height of the first unit and the defined height of the second unit, whereby the height offset of the location of the emission of the laser beam to the mounting location of the laser source and the offset between the detection position and the location of the detector is taken into account. Embodiments of the present invention is based on the finding that the layer thickness of a newly applied material layer, for example an asphalt layer by means of a laser transmitting unit and by means of a laser receiving unit can be measured by applying the unit in a fixed and known height to the substrate on which the layer is guided, while the other unit is guided in a fixed and also known height to the surface of the applied layer. Preferably, the two elements are then arranged at approximately the same absolute height so that the detector can detect a relative change between the two units if the detector can determine the point of impact of the laser beam and thus the impact height. Since the corresponding heights are known, the offset between the two surfaces (background, applied layer) and consequently also the layer thickness can be determined in this way. In other words, this means that each position or impingement point on the laser detector is assigned to a specific height difference between the laser transmitter and the laser detector, which corresponds to the layer thickness of the installed road surface. Thus, it is thus advantageously possible to directly determine the layer thickness when applying the road surface to the substrate and to react immediately in the event of deviations, so that "latency distances" do not occur, as in the prior art The advantage of the rotary laser is that it simplifies the alignment of the laser source and the laser detector, as a rule, the laser beam or the laser beams, for example at the laser plane, are essentially parallel to the background, ie Substantially orthogonal to a direction of travel of the paver and substantially orthogonal to a width of the screed., The term "substantially" implies that 100% parallelism or 100% orthogonality is not mandatory, so that deviations to, for example, 1 °, 3 ° or even 5 ^{0 is allowed} in terms of parallelism or orthogonality, or generally a deviation of 5 degrees, so that the orthogonality or parallelism condition is satisfied.

According to further embodiments, the measuring system comprises two laser source / laser detector pairs, for. B. at different heights. Alternatively, two laser detectors can be provided, which can be mounted on the left or right on the screed or left and right on the paver, for example, so that when starting from a laser that spans a laser plane parallel to the ground, goes through the height difference between left / right can detect a tilting of the screed. According to further embodiments, the two detectors also two Laserqueiien are used, which are preferably (but not necessarily) arranged at different heights, so that the tilting of the two laser source / laser detector pairs is detectable. In both exemplary embodiments, the calculation of the transverse tilting takes place with the aid of the calculation device in such a way that a comparison of the positions of the two laser detectors is determined. Thus, as a result, it is advantageously possible to determine not only the height of the screed but also an inclination thereof.

Further exemplary embodiments provide a measuring system in which an operating unit, in particular for visualizing the layer thickness, is provided. In this case, the operating unit as a smart device such. B. be designed as a tablet PC. According to further embodiments, the height signal can not only be visualized, but also be used directly for control. Therefore, according to further exemplary embodiments, the measuring system comprises a control which is designed to control the road finisher for height regulation in such a way that the screed can be varied along the height axis. Further embodiments relate to a measuring system in which a (longitudinal) tilting of the screed with respect to a direction of travel of the paver can be determined. As such, longitudinal tilting (i.e., orthogonal to the width and elevation axis) is detected. The detection of the tilting takes place, for example, in that two laser beams are emitted by the laser source in two different heights to the laser detector. Here, the two laser beams z. B. fanned out in V-shape, in which case according to a preferred variant, the two laser beams form a right triangle together with the elevation axis. By the transit time differences of the two laser beams then a tilt can be determined. It should be noted at this point that the two laser beams can also occur in each case in one laser plane (see above, rotational laser). In this group of embodiments, it is advantageously possible that with the aid of the calculation unit, the longitudinal tilting of the screed immediately d. H. can be detected without latency.

According to further embodiments, instead of the one unit on the road finisher (fixed coupled with the chassis of the paver) this unit also on an extra party recipient, such. B. an additional landing gear, which, for example, in Tensile or shear direction is coupled to the paver of the screed, be attached. This additional landing gear will be guided at a defined height to the ground (on which the paving is soft), so that the functionality here is analogous to that explained above. According to embodiments, this auxiliary undercarriage may comprise a so-called "telescopic mechanism", which allows the additional undercarriage to always be guided perpendicular to the ground, these embodiments advantageously allowing the auxiliary undercarriage to respond to significantly smaller unevenness of the ground compared to the paver's chassis, which can not follow the small bumps due to its tires in several Aufaufspunkte.

It should be noted that both laser sources and laser detector preferably detachable, z. B. by means of a simple fastening mechanism or by means of a magnet to paver and screed are fastened bar.

Further exemplary embodiments relate to a method for detecting layer thickness for the above-mentioned road paver. Here, the method comprises the steps of emitting a laser beam to the laser detector, detecting a position of the laser beam along the height axis over a range of the laser detector, and determining from the position of the laser beam the slice thickness. The above-explained assumptions regarding the position of the laser source for the laser beam and the laser detector for detection persist. According to the further embodiments, a computer program for carrying out the described method is provided. Further developments are defined in the subclaims. Show it:

1 is a schematic block diagram of a measurement system according to a basic embodiment; 2a-c schematic representations of a road paver in combination with three different variants of a measuring system according to further embodiments;

3 shows a schematic representation of a laser measuring system in combination with an additional landing gear according to a further exemplary embodiment; and 4 shows a schematic representation of a laser measuring system with the additional functionality of the longitudinal angle detection according to a further exemplary embodiment.

Before explaining embodiments of the present invention with reference to the figures, it should be noted that the same reference numerals are provided for the same elements and structures, so that the description of which is mutually applicable or interchangeable.

FIG. 1 shows schematically a road paver 10 with a screed 34 which can be pulled behind, for example by means of a mechanism 32. The road paver 10 has, for example, a chassis which is (fixedly) coupled to the chassis 31. About the chassis 31, it is moved on the ground 20 in the direction FR. Here, the screed 34 is pulled behind and distributes the material of the pavement 35, so that the road surface 35 is pulled smoothly and a flat surface is formed. In this case, the road surface 35 has a (for example, constant) layer thickness SD. SD illustrates the height of the surface 35 o of the road surface 35 with respect to the ground 20.

Since the screed 34 rests on the surface 35o, based on the height difference between the screed 34 and the contact point of the undercarriage 31 on the ground 20, the layer thickness SD can be calculated. To determine the height difference, a measuring system 100 is installed on screed 34 and paver 10 (or its chassis). The measuring system 100 comprises a laser source 51 and a laser detector 61. The laser source 51 is installed in this embodiment on the chassis 10 and designed to emit a laser beam L1 in the direction of the detector 61.

In this embodiment, the detector 61 is mounted on the screed 34 (in the area of the screed trailing edge) and designed to determine the laser beam L1 or, more precisely, its position 61p. Depending on whether the detector 61 is moved along the elevation axis HA (up or down), the position 61p on the detector 61 varies. Within the area 61b of the detector 61, the position 61p of the laser beam L1 can be detected. In this embodiment or in the illustration, the point 61 p hits 61 h in height. By determining the height 61 h of the laser beam L1 by means of the detector 61, it is already possible to detect a relative change in height of the screed 34, and consequently also a relative change in the layer thickness SD, since the detector 61 is thus coupled to the screed 34, that it is moved together with the screed 34 along the elevation axis HA. For example, the variation can be Reichs 61 b. In the exemplary embodiment illustrated here, the beam L1 impinges on the height 61 h.

1, it is assumed that the laser source 51 or generally the first of the two units of the measuring system 100 (ie either the laser source 51 or the laser detector 61) at a predetermined and known height 51 bh to the ground 20 is arranged. Here, the predefined height 51 bh refers to the amount of emission of the laser beam L1 offset, for example, by an offset 51 v with respect to the actual connection between the laser source 51 and the chassis of the paver 10 along the axis HA. In other words, this means that the height 51 bh is composed of the distance between the mounting location of the laser source 51 with respect to the plane 20 and the offset 51 v. Analogously, the laser detector 61 or generally the second of the two units of the measuring system 100 is arranged in a known height 61 bh, wherein here 61 bh refers to the distance between the surface 35 o and the beginning of the region 61 b. It should be noted that the height 61 bh in turn comprises an offset 61 v, around which the region 61 b relative to the mounting location (lower attachment point of the detector to the holder 65 or 66, see Fig. 2a-c, 3 and 4) of the detector 61 is shifted along the axis HA. Here, the laser beam L1 hits the height 61h of the region 61b, so that a total height value 61 ha of the impact point 61p with respect to the surface 35o results. This height value of 61 ha varies depending on the layer thickness SD and thus also depending on the detected height 61 h. In other words, this means that the height value 61 ha has a variable portion 61 h (as a function of the layer thickness SD) and a predefined or known proportion 61 bh.

The variable component 61 h can be determined by means of the position 61 p by means of the detector 61, so that by the detection of the point 61 p or to be precise, the height 61 h can be drawn a conclusion on the layer thickness SD.

This inference is carried out, for example, by a calculation device (not shown) which determines the layer thickness SD as a function of the determined value 61 h. If the height of the screed 34 changes in relation to the chassis of the road paver 10, for example due to unevenness of a reference line attached to the roadside or due to so-called "rising and falling" of the screed 34, this changes Consequently, the layer thickness SD of the newly applied road surface 35. A change in the altitude of the screed 34 in relation to the chassis of the paver 10, however, is detected by the measuring system 100, in particular by the laser receiving unit 61. The information regarding the altitude of the screed 34 is either for logging purposes, for visualization purposes or for control purposes other units, such. B. a controller or a Bedienpanei provided.

Although in the above embodiment of FIG. 1 it has been assumed that the laser source 51 is arranged on the chassis of the paver 10, while the laser detector 61 is fixedly coupled to the screed 34, it should be noted that the arrangement may also be exactly mirrored, so that for example the detector 61 moves in a continuous distance to the ground 20 together with the chassis of the paver 10, while the laser beam of the laser source 51 is moved together with the screed 34 along the elevation axis HA.

According to further embodiments, a so-called rotary laser can be used as the laser unit 51, which is just attached to the chassis of the paver 10. The rotating laser beam thus biases a laser plane comprising a plurality of laser beams, which are then received or scanned by the laser receiving unit 61. The laser receiver 61 may, for example, be a laser receiver suitable for use in the construction industry, as disclosed in EP 1 983 299. As already explained above, the laser receiving unit 61 calculates a height information 61 h, sends it to a, for example, on a paver 10 arranged control computer for determining the layer thickness.

Referring to FIGS. 2a-d, further variants of a measuring system 100 will now be explained.

Fig. 2a-c shows each a paver 10, which moves over a substrate to be processed 20 while a new material layer 22, such. As an asphalt, applies.

Road pavers 10 of this type are well known. They usually have a material bunker 30 in the front region, in which material 35 is continuously introduced during the production process. The material 35 is transported via conveyor belts, not shown, in the rear region of the paver 10 and distributed over a screw 33 in front of the screed 34. The screed 34 substantially flattens the material 35 and optionally further densifies it. The screed 34 is not rigidly connected to the chassis of the paver, but is pulled by pulling arms 32, which are arranged laterally left and right of the paver 10. By lifting and leveling the traction arms are changed in height, whereby the altitude of the screed 34 changes accordingly, ie the screed moves during the manufacturing process according to up or down (see elevation axis HA).

To regulate the altitude of the screed 34, a leveling system with appropriate sensors is usually used. Sensors (not shown) measure, for example, the distance of the screed to the ground 20 or to a reference, not shown, for example, a stretched along the road to be manufactured line. Furthermore, the leveling system usually comprises a display and operating unit 40, which is arranged either only on one side of the screed 34 or on both sides of the screed 34. Hereby, installation parameters of the production process for the screed personnel are visualized or can be changed by the screed personnel or adapted to specific installation situations.

For operation and control of the paver 10, this further has a driver's station 36 and a control panel 42, in which input and display devices are integrated. The driver thus also has an overview of installation parameters of the manufacturing process and can control the paver accordingly, for example, increase or decrease the installation speed. In order to determine the layer thickness SD of the newly installed material layer 22, the paver 10 according to one embodiment has a laser transmitting unit 51 or 52, for example a rotary egg, which is arranged on the chassis of the paver 10. In the exemplary embodiment from FIG. 2 a, only the laser transmitter 51 is used, while in the exemplary embodiment from FIG. 2 b only the laser transmitter 52 is used. The two laser transmitters 51 and 52 are arranged at different heights. Alternatively, an arrangement on different sides in width planes (left / right) of the paver 10 would be conceivable. The Ausführungsbeispiei of Fig. 2c shows the use of both laser transmitters 51 and 52. The laser transmitting unit 51, 52 emits a laser beam L1, L2, for example, a rotating laser beam, and thus "spans" a laser plane, which from a laser receiving unit 61 and 62 is received or sampled. The laser receiving unit 61 is at the height of the laser transmitter 51, while the laser receiving unit 62 is disposed at the height of the laser transmitter 52. In this respect, in the embodiment of Fig. 2a, the laser receiving side L61 is used, while in the embodiment of Fig. 2b, the laser receiving unit 62 is used. In an embodiment of Fig. 2c, both laser receiving units 61 and 62 are used. The laser receiving unit 61 and 62 is arranged on the plank 34 via a holder 65 and 66. Preferably, the laser transmitting units 51/52 and the laser receiving units 61, 62 are spaced about 2 m apart or generally within the range of 50 cm to 8 m. The laser receiving unit 61, 62 calculates a height information and sends it to an arranged on the paver control computer 71 for determining the layer thickness of the newly installed material layer 22. In this case, the laser receiving unit 61, 62 may be connected either by cable to the control computer 71; However, a wireless connection is also conceivable. For this purpose, a communication unit 72 is connected to the control computer 71, which can communicate wirelessly with various components. This can for example be arranged on the paver components such as the laser receiving unit 61, 62 or even the display and control unit 40, or even external components such as mobile devices such as a laptop 81, a smart phone 82 or a tablet PC 83rd be as shown in particular in Fig. 2c.

However, it is also conceivable that a smartwatch or data glasses or the like (not shown) can receive the signals 76 emitted by the communication unit 72. The components arranged on the road paver 10 have a corresponding communication unit 78 which enables a wireless connection as described.

From the measured values of the laser receiving unit 61, 62 and the known mounting height of the laser transmitting unit 51, 52, the control computer 71 can calculate the layer thickness of the newly installed material layer 22. If the altitude of the screed 34 changes in relation to the chassis of the paver and in relation to the mounting height of the laser transmitting unit 51, 52, then the layer thickness of the newly applied road surface 22 changes as well. The layer thickness calculated by the control computer 71 can be changed either on the control panel 42 be displayed or used to control to a predetermined value of the layer thickness. To the value of Layer thickness display on the control panel 42, this is connected by means of a cable 75 to the control computer 71.

According to further embodiments, the configuration of Fig. 2c may be used with the two laser transmitting units 51 and 52 and the two laser receiving units 61 and 62 arranged, for example, on two different sides (left / right) of the paver 10 and the screed 34, respectively to determine a tilt to the left / right. The determination of the tilting is possible because the height determined on the left side deviates from the height determined on the right side, so that a conclusion on the tilt can be drawn from the deviation and from a known distance of the two laser receivers 61 and 62. The arrangement of the laser transmitter-laser receiver pairs 51 + 61 and 52 + 62 is advantageous because they do not affect each other so. Alternatively, it would also be conceivable that a laser transmitter, which spans a laser plane, is used for both laser receivers 61 and 62, if they are arranged, for example, at the same height.

According to embodiments, in the above embodiments, it has been assumed that the laser beams Li and L2 and the laser planes including the laser beams L1 and L2 are substantially parallel to the ground 20, respectively. In this case, "substantially" means, for example, with a deviation of less than 5 ° or less than 1.degree .. Parallel to exemplary embodiments, it has been assumed that the height plane HA is perpendicular, ie orthogonal to the width plane and orthogonal to the direction of travel FR or plane 20 Here, "orthogonal" again means "substantially orthogonal", ie with a deviation of s 5 ° or s 17 of 90 °.

According to an alternative variant, a laser transmitting unit is arranged on a pulling or pushing part instead of on the chassis of the paver, wherein the pulling or pushing part is located on the substrate to be processed in front of the screed. This exemplary embodiment is shown in FIG.

3 schematically shows a laser transmitting unit 51, 52 arranged on a pulling or pushing part 90, wherein the pulling or pushing part 90 moves in front of the screed 34 on the substrate 20 to be processed. The pulling or pushing part 90 is connected via a height-movably mounted mechanism 91, 93 (telescopic bearing) with the screed 34, wherein this mechanism is attached to the screed itself rotatably mounted again (sie- he BZ 92). By means of the mechanism 91, 93, the existing surface 20 is "copied" in front of the screed 34 and transmitted by the laser transmitting unit 51, 52 to the laser plane Li, L2 and thus to the laser receiving unit 61, 62. This pulling or pushing part can correspond to further embodiments also be embodied as a different kind of auxiliary landing gear, which copies the height profile of the substrate 20, so that by means of the laser transmitting unit 50 or 52 height changes of the ground so transmits that they are detectable by means of the laser detector 60, 61. The advantage of such an additional landing gear or in the above-described pull and push part is that even small changes in the ground 20 are detectable, which is not possible, for example, when using the standard chassis of the paver 10. At this point it should also be noted that the above-mentioned telescopic storage tilting the laser unit 51, 52 largely prevented, so that eleven Liche errors in the height calculation can be excluded.

According to further embodiments, the laser detector can also be interchanged with the laser transmitting unit in this variant, so that therefore the laser detector is arranged on the additional landing gear while the laser transmitter is connected to the screed.

According to further embodiments, the measuring system can be designed to detect tilting of the screed with respect to the longitudinal axis (see direction of travel). For this purpose, the laser transmission unit is designed to emit a "fanned-out" point laser cone or two laser beams emitted at a predefined angle in a V-shaped manner.Thus, two laser distance sensors arranged at a predetermined angle can be used for this purpose explained on Fig. 4.

4, the laser transmitting unit 51, 52 may also be a "fanned-out" point laser or two laser distance sensors arranged at a predetermined angle to the laser receiving unit 61, 62. By an integrated distance measurement, the distances L1 / L1 'or L2 / L2' between the laser transmitting unit 51, 52 and the laser receiving unit 61, 62 are determined continuously, whereby tilting of the laser receiving unit, for example, when loading the paver detected and computationally compensated by the control unit 71 can be. This is particularly advantageous in the case of regulation to a predetermined and constant layer thickness, since disturbing influences occur in the regulation during each loading process, which could be compensated or minimized with the structure according to FIG. 4. Another embodiment provides a measurement system with an additional GNSS or GPS receiver. In order to be able to assign the measured layer thickness values to corresponding positions (so-called georeferenced data), an additional GNSS receiver can be arranged, for example, on the roof of the road finisher.

Further embodiments have an additional communication interface for exporting or generally displaying the data. The measured data can be displayed on a display unit 42, both on the driver's station 36 and on the external control stations 40 on the left and right of the screed 34. The measured data can be transmitted via an additional communication interface 72 (WLAN / Bluetooth, etc.) also be transmitted to a nearby construction site office or to a person standing on site (site supervisor) and displayed on a tablet PC, smartphone, smartwatch, etc.

With the aid of the measuring system, it is conceivable to regulate to a predefined layer thickness, for example 5 cm, in the case of a top layer (top layer and last applied asphalt layer).

According to further embodiments, the units of the measuring system or in particular of the laser transmitting unit 51, 52 or laser detector 61, 62 can be realized with releasable fasteners.

All components are detachably attached to the machine. In the holders 65 and 66 for the laser receiving units vibration-damped brackets are useful because they dampen the vibrations of the screed. Although it has been assumed in the above exemplary embodiment that the measuring system is implemented as a device, it should be pointed out that a further exemplary embodiment relates to a corresponding method, in particular a calculation method for determining layer thickness. The method comprises the basic steps of emitting a laser beam, detecting the position or height of the laser beam by means of an oppositely arranged detector, wherein the laser source and the laser receiver are at a constant height to the ground on which they are to be stored. is to be applied, is arranged, or at a constant height to the surface of the currently applied layer. In a last step, the layer thickness is then calculated taking into account the known, constant heights on the basis of the determined position of the detected laser beam.

Although some aspects have been described in the context of a device, it will be understood that these aspects also constitute a description of the corresponding method such that a block or device of a device is also to be understood as a corresponding method step or feature of a method step , Similarly, aspects described in connection with or as a method step also represent a description of a corresponding block or detail or feature of a corresponding device. Some or all of the method steps may be performed by a hardware device (or using a hardware device). Apparatus), such as a microprocessor, a programmable computer or an electronic circuit. In some embodiments, some or more of the most important method steps may be performed by such an apparatus.

Depending on particular implementation requirements, embodiments of the invention may be implemented in hardware or in software. The implementation may be performed using a digital storage medium, such as a floppy disk, a DVD, a Blu-ray Disc, a CD, a ROM, a PROM, an EPROM, an EEPROM or FLASH memory, a hard disk, or other magnetic disk or optical memory are stored on the electronically readable control signals, which can cooperate with a programmable computer system or cooperate such that the respective method is performed. Therefore, the digital storage medium can be computer readable.

Thus, some embodiments according to the invention include a data carrier having electronically readable control signals capable of interacting with a programmable computer system such that one of the methods described herein is performed.

In general, embodiments of the present invention may be implemented as a computer program product having a program code, wherein the program code is operable to perform one of the methods when the computer program product runs on a computer. The program code can also be stored, for example, on a machine-readable carrier. Other embodiments include the computer program for performing any of the methods described herein, wherein the computer program is stored on a machine-readable medium.

In other words, an embodiment of the method according to the invention is thus a computer program which has a program code for performing one of the methods described herein when the computer program runs on a computer.

A further embodiment of the method according to the invention is thus a data medium (or a digital storage medium or a computer-readable medium) on which the computer program is recorded for performing one of the methods described herein.

A further exemplary embodiment of the method according to the invention is thus a data stream or a sequence of signals which represents or represents the computer program for performing one of the methods described herein. The data stream or the sequence of signals may be configured, for example, to be transferred via a data communication connection, for example via the Internet.

Another embodiment includes a processing device, such as a computer or a programmable logic device, that is configured or adapted to perform one of the methods described herein. Another embodiment includes a computer on which the computer program is installed to perform one of the methods described herein.

Another embodiment according to the invention comprises a device or system adapted to transmit a computer program for performing at least one of the methods described herein to a receiver. The transmission can be done for example electronically or optically. The receiver may be, for example, a computer, a mobile device, a storage device, or a similar device. be direction. For example, the device or system may include a file server for transmitting the computer program to the recipient.

In some embodiments, a programmable logic device (eg, a field programmable gate array, an FPGA) may be used to perform some or all of the functionality of the methods described herein. In some embodiments, a fid programmable gate array may cooperate with a microprocessor to perform any of the methods described herein. Generally, in some embodiments, the methods are performed by any hardware device. This may be a universal hardware such as a computer processor (CPU) or hardware specific to the process, such as an ASIC.

The embodiments described above are merely illustrative of the principles of the present invention. It will be understood that modifications and variations of the arrangements and details described herein will be apparent to others of ordinary skill in the art. Therefore, it is intended that the invention be limited only by the scope of the appended claims and not by the specific details presented in the description and explanation of the embodiments herein.

Claims

claims

Measuring system (100) for detecting layer thickness for a road paver (10) with a screed (34), comprising: a laser detector which is designed to move over a region (61 b) along a height axis (HA) to a position (61 p) to detect a laser beam (L1, L2); a laser source arranged to emit the laser beam (L1, L2) to the laser detector (61, 62); and a calculation unit (71); wherein a first of two units comprising laser detector (61, 62) and laser source (51, 52) is connected to a chassis (31) of the paver (10) or a reference receiver (95) of the paver (10), so that the first unit is guided at a defined height (51 bh) to a base (20) for a layer to be built in, and a second of the two units is connected to the screed (34) which rests on the layer to be installed, so that the second unit is moved as a function of the layer thickness (SD) along the elevation axis (HA), the calculation unit (71) being formed starting from the position (61 p) of the laser beam (L1, L2) along the elevation axis (HA) to determine the layer thickness (SD).

The measurement system (100) of claim 1, wherein the laser source (51, 52) comprises a rotating laser configured to span a laser plane including a plurality of laser beams (L1, L1 ', L2, L2').

A system according to any preceding claim, wherein the laser beam (L1, L2) is substantially parallel to the ground (20); and or wherein the elevation axis (HA) is substantially orthogonal to a direction of travel (FR) of the paver (10) and substantially orthogonal to a width of the plank (34).

Measuring system (100) according to one of the preceding claims, wherein the measuring system comprises two laser detectors (61, 62).

Measuring system (100) according to claim 4, wherein the measuring system (100) comprises two laser sources (51, 52).

Measuring system according to claim 4 or 5, wherein the two laser detectors (61, 62) are mounted at different heights.

Measuring system (100) according to one of claims 4 to 6, wherein the two laser detectors (61, 62) and / or the two laser sources (51, 52) are arranged on two different sides of the screed (34), wherein the calculation unit (71) is formed by comparing the two positions (61 p) of the laser beams (L, L2) of the two different detectors to determine a transverse tilting of the screed (34) relative to the height axis (HA).

Measuring system (100) according to one of the preceding claims, wherein the measuring system (100) has an operating unit (40) and / or a smart device (81, 82, 83) for visualizing the layer thickness (SD).

Measuring system (100) according to one of the preceding claims, wherein the measuring system (100) has a control which is designed to control the height adjustment of the paver (10) so that the plank (34) along the elevation axis (HA) is variable , 10. Measuring system (100) according to claim 9, wherein a height position along the height axis (HA) is directly dependent on the layer thickness (SD).

Measuring system (100) according to one of the preceding claims, wherein the calculation unit (71) is designed to determine a tilt of the screed (34) against a direction of travel (FR) of the paver (10). Measuring system (100) according to claim 1 1, wherein the laser source (51, 52) is adapted to emit two laser beams (L1, L2, L1 ', L2') at two different levels to the laser detector (61, 62).

A measuring system (100) according to claim 12, wherein the two laser beams (Li, L2, L1 ', L2') are fanned out; and / or wherein the two laser beams (Li, L2, L1 ', L2') are fanned out such that the two laser beams (L1, L2, L1 ^!, L2 ') together with the elevation axis (HA) form a right-angled triangle.

Measuring system (100) according to any one of claims 12, 13, wherein the calculation unit (71) is adapted to the tilting of the screed (34) relative to the direction of travel (FR) based on a transit time difference of the two laser beams (L1, L2, L1 \ L2 ').

Measuring system (100) according to one of the preceding claims, wherein the reference person (95) is formed by an additional chassis, wherein the auxiliary chassis is guided on the ground (SD), so that the first unit always at a defined height to the ground ( SD).

Measuring system (100) according to claim 15, wherein the auxiliary undercarriage is fastened in the pulling or pushing direction to the screed (34) and / or to the road paver (10).

Measuring system (100) according to claim 15 and 16, wherein the auxiliary landing gear has a telescopic mechanism which is designed to guide a wheel of the auxiliary undercarriage (94) along the height axis (HA).

Measuring system (100) according to one of the preceding claims, wherein the first unit and / or the second unit are fastened by releasable connections to the paver (10) and / or the screed (34).

Method for detecting layer thickness for a road paver (10) with a screed (34), comprising the following steps:

Emitting, by means of a laser source (51, 52), a laser beam (L1, L2) to a laser detector (61, 62); Detecting, by means of the laser detector (61, 62), a position (61p) of the laser beam (L1, L2) along an elevation axis (HA) over a region (61b); wherein a first of two units, comprising laser detector (61, 62) and laser source (51, 52), is connected to a chassis (31) of the paver (10) or a reference receiver (95), so that the first unit in a defined Height (51 bh) to a substrate (SD) for a layer to be installed, and a second of the two units with the screed (34), which rests on the layer to be installed, is connected, so that the second unit in dependence on the layer thickness (SD) is moved along the elevation axis (HA); and

Determining from the position (61 p) of the laser beam (L1, L2) the layer thickness (SD).

A computer program comprising program code for performing the method of claim 19 when the program is run on a computer.