HK1115904A - System for co-ordinated ground processing - Google Patents

Description

System for collaborative ground processing

Technical Field

The invention relates to a system for collaborative ground treatment, and to a method for compacting at least one ground area (3) or at least one covering area applied on a ground area to a predetermined area-specific compaction nominal value, a compaction device of the system, and a method for operating the system.

Background

WO 2005/028755 (amann) discloses a method and apparatus for determining relative and absolute ground hardness values for a ground area. The device is operated in close contact with the ground to determine an absolute ground hardness value. In this case, the ground and the device form a single oscillating system. In order to determine the relative values, the device is moved over the ground in a hopping fashion, wherein amplitude values and frequency values of the subharmonic frequencies formed relative to the excitation frequency are estimated during this process. An absolute measurement relates to a measurement at one location, while a relative measurement is taken while driving over an area. Since the relative measurement is to be converted into an absolute value via an absolute measurement, the relative ground hardness measured while driving in this region for compaction purposes can be converted into an absolute value of the ground hardness. The values determined in this case are displayed to the driver of the compacting device, who then has to decide on further compacting processes.

DE 19956943 a1(Bomag) describes a device for monitoring the compaction of a vibration compaction device. Compaction monitoring is used to measure and display a first compaction measurement of an asphalt road in road construction, which is generated by a first compaction device and then compared to a second compaction value generated by a second compaction device, which is determined when the asphalt temperature is substantially the same. The second compacting device is coupled to the first compacting device such that it moves along the same trajectory as the first compacting device. In this case, two separate rollers (roller train) may be provided, which are coupled to one another via a computer-assisted slave system or steering system (steering system). The coupled steering on the right trajectory can be performed by means of the Global Positioning System (GPS) or radar, ultrasound or infrared. The degree of compaction achieved can be derived by measuring the oscillation reflection during compaction. When the number of compactions performed over this area has increased and the level of compaction in the compaction monitoring device no longer changes, it is assumed that the maximum compaction density achievable by a particular compaction device has been achieved. The reached compaction value is indicated to the driver of the road roller on a display unit.

Disclosure of Invention

It is an object of the invention to provide a system in connection with the initially mentioned technical field, with which an optimal ground compaction can be achieved within an optimal time frame.

The above object is achieved by the features of claim 1. According to the invention, the system for the collaborative ground treatment has a plurality of compacting devices for ground compacting, which are designed to determine position-dependent relative compaction values. The system further comprises a calibration device for determining a position-dependent absolute compaction value and a calculation unit for performing a correlation calculation between the position-dependent relative and absolute compaction values, wherein the compaction device, the calibration device and the calculation unit are interconnected for information transfer. Finally, the system controller is provided and designed such that the position-dependent relative compaction value and the position-dependent absolute compaction value of the compaction device are continuously transmitted to the computing unit and stored therein, and if there is a compaction value of the same position, a compaction-related value is computed and transmitted to the compaction device and stored therein as a correction value.

This is an all-in-one system that can monitor, coordinate and control compaction tasks at large construction sites, where multiple (i.e., at least two, preferably more than three) compaction devices (rollers, diaphragms, etc.) can be used at different locations, either simultaneously or sequentially over time. A calibration device (e.g., a pressure plate) associated with the system may be used to calibrate or match the compaction device, for example, used at a different location on the construction site, that has processed the calibration location or at least determined the relative compaction values at that location. In the present system, the compression value is always provided together with the position coordinate, i.e. the correct data record contains at least the compression value and the position value. Other data such as time, machine identifier, formation thickness, material properties may be further appended.

The system controller may be implemented in a number of different ways. It is generally a computer program with various modules installed on the compacting device, the calibration device and the central computing unit, monitoring the timing and communication for information transfer. As an example, the computing unit may examine various devices.

The computing unit is typically contained in a server at a fixed location, and may be constituted by software installed on the server. The calculation unit may also be provided on a device being used at the construction site, such as a calibration device or a compacting device. Information may be transferred between devices using a separate private network or a commonly available public network (e.g., GSM, wireless phone).

A typical system according to the invention has a plurality of rollers (weight, power, technology). It is therefore worthwhile to identify each compacting device with a code and to provide each measurement with an identifier of the compacting device. The system can be extended in such a way that new devices can be added (or integrated into the system) when needed. Furthermore, this makes it possible to monitor the quality of the compaction device, since various comparison options are always present.

Of course, it is more feasible for the system to be peripheral controlled rather than central controlled. This means that each compaction device autonomously checks with the control centre (calculation unit) whether the compaction value of the site it is being used has already been recorded and, if available, the control centre sends the existing value. Thus, the control center does not need to store the compaction value and the identifier.

The data are mainly stored in a computing unit, where in practice a map made up of the data is formed for the terrain to be processed. The system controller preferably ensures that the compaction devices move to the position of the absolute calibration measurement at specific intervals and/or according to the number and placement of the relative compaction values available, where they determine the relative compaction values, and then compare or correlate the relative compaction values to calibration values. When the compacting device is correlated or calibrated in this way by means of calibration measurements, the sub-area of the ground that has been processed by the calibrated compacting device can be used again (possibly only temporarily) as a reference for another compacting device that has not yet been calibrated. In this way, the measuring systems of the compacting device can be systematically and continuously adapted to one another throughout the entire system.

For simplicity of description, it is also possible to store only stationary specific calibration sites in the system. Correlation calculations are then made for only these individual locations, so that there is no need to store a ground compaction data map.

The arrangement according to the invention of the devices that can communicate with each other is preferably configured in the form of a complete building site management system. The technical and physical properties of the ground area are also stored in a corresponding manner (e.g. geometry, compactness and other properties of the ground layer). The data required for the cost calculation is also recorded. This means that the terrain (e.g. the route of a road) can be prepared more quickly and cost-effectively.

The positioning process may be performed in various ways. Each unit is preferably equipped with a GPS receiver (i.e. using the common form of receiver for satellite based positioning). Locally, the location can also be determined using a reference system specific to the construction site (with a fixed-location transmitter/receiver, the orientation of the unit can be determined with reference to the transmitter/receiver).

The calibration device is preferably a standard device (DIN 18196) for performing the platen experiments. Such a device can also be used as a calibration device in the system of the invention if standard or construction site management allows the use of different devices for determining the absolute compaction value, such as road rollers designed to determine the absolute compaction value or vibrating plates for determining the absolute ground hardness value (WO 2005/028755, amann). It is therefore possible to use a further compaction device as a calibration device and to determine not only the relative compaction values but also the absolute compaction values. In this connection, it is to be noted that the system according to the invention may in fact also have a plurality of calibration means.

The system according to the invention can be operated in a number of very different ways. A compacted ground area may be produced, for example, by the following steps:

a) the compacting device drives over at least one sub-region of the ground area, the compacting device determines at least one position-dependent relative compacting value when driving over the region,

b) the position-dependent absolute compaction value in the subregion is determined by means of a calibration device,

c) automatically sending information about the relative and absolute compaction values related to the position determined in step a) and step b) to a calculation unit,

d) determining at least one correlation value between the relative and absolute compaction values,

e) automatically sending the correlation value to a compaction device, an

f) If necessary, the reference values in the compacting means are readjusted corresponding to the transmitted correlation values.

The calibration device may be used first to determine a position-dependent absolute compaction value, and the compaction device may be moved past the respective partial region at a later time in a non-compacting manner to determine at least one position-dependent relative compaction value while moving past the respective partial region.

However, it is also possible for the compacting device to initially travel over the partial region in a compacting manner, to determine at least one position-dependent relative compaction value when traveling over the partial region, and to determine a position-dependent absolute compaction value at a later time.

Usually, a plurality of (at least two, preferably three or more) partial regions are traversed by the first compacting device and the further compacting device. The position-dependent relative compaction values are transmitted to a control center, which calculates the correlation between the individual measured values and thus the correlation between the compacting devices.

One advantage of the present invention is that it reduces the amount of work required by a person (e.g. a road roller driver) who must drive the compaction apparatus. Since the invention enables, among other things, the machine settings (travel route, travel speed in the area and compaction value) for optimized compaction to be automatically obtained in a reduced time, the compactor driver can concentrate his full attention on the compactor drive and on observing safety situations. This avoids the subsequent "shake up" of the ground area by driving it again unnecessarily. Driving through this region again, which is necessary, for example, to reach regions which still require compaction, can be carried out in such a way that "sloshing" is no longer performed. A set comprising a plurality of compacting devices may also be used, which may furthermore use different power equipment for any compaction task to be performed.

To achieve this, a compacting device is used whose compaction value can be set automatically. In particular, the compaction value is an adjustable ground reaction force (F)_BAnd phase angle *. Phase angle * is the maximum ground reaction force F normal to the ground area_BAnd the maximum oscillation value of the oscillation response of the oscillating system. As described below, this oscillating system is composed of a ground area and an oscillating unit in the compacting device that performs the task of compacting. The compaction process typically uses an imbalance (imbalance) having an imbalance moment (imbalance moment) and an imbalance frequency. Thus, in the case of the invention, the compaction value is set automatically by the controlled adjusting device, and the unbalance moment and the unbalance frequency are controlled similarly, i.e. they are set to be determined by the computing unit.

For example, when driving for the first time over an area, the adjustment unit sets the imbalance moment and the imbalance frequency such that a predetermined nominal compaction value of this ground area or cover area is achieved on the basis of theoretical calculations. The nominal compaction value is usually constant over a long distance, but not necessarily, because the unbalance moment and unbalance frequency can be automatically adjusted. As will be particularly noted below, the achieved ground compaction value is determined immediately upon driving over the area, and the determined actual compaction value is stored with the location coordinates of the area for subsequent processing.

By compaction value is meant the displacement of the compaction means that produces the compaction. The so-called "compaction" in each instance relates to the area of the ground or covering to be compacted or being compacted.

This subsequent processing may include driving through the area again for compaction, or other processing of the area if repeated measurements of the location-dependent compaction values indicate that the area cannot be compacted further (e.g., due to its texture, underlying terrain, etc.).

The inability to compact further may be confirmed by determining an actual compaction value based on location during each compaction and by storing the actual compaction value. These stored values are compared. If no (significant) increase in compaction value is found, the region can practically not be recompressed. In order to prevent damage in this region due to further compacting and to save time, an imbalance moment and an imbalance frequency can be set in this region such that the effect of only leveling the surface is achieved when passing through this region.

An imbalance moment and an imbalance frequency for a surface-smoothing effect when driving over an area can also be set when the area has been compacted to a predetermined compaction value and a nearby area or an area on a predetermined course has not yet reached the predetermined compaction value. This surface-smoothing "reset" of the machine compaction data makes it possible, on the one hand, to drive through the region more quickly and, on the other hand, to avoid the already compacted region from "rolling up" again.

In contrast to known ground compacting systems, the ground reaction force F may be determined and set directly at the relevant location (region)_BAnd a phase angle *. In contrast to the "manually set" compacting devices described in the prior art, the compacting device according to the invention is an "automatic compacting device".

If multiple regions have been sufficiently compacted, the regions may be bypassed. The calculation unit, which is processing the position-dependent actual compaction values from the memory unit, will suggest a route to the compaction apparatus driver. The suggested route may be displayed on a display unit of the cab. However, the course can also be reflected onto a so-called windscreen or be displayed directly on the ground area by means of a light beam, in particular a laser (for example a red helium-neon laser beam). The advantage of being displayed on the ground is that it is possible to clearly indicate the path that the worker is about to compact, or the areas that do not have to enter, or the areas that the machine must move away.

In the case of relatively large construction sites, a plurality of compacting devices is often used, which also have different device data for the compacting to be performed. The logic of each compaction device knows its specific compaction characteristics and can suitably set the unbalance moment and unbalance frequency by the adjustment unit according to predetermined nominal compaction values.

Since larger masses are typically used to generate the oscillations required for compaction, it is preferable to provide a timer. The timer knows the typical adjustment time of the machine and therefore also the time interval for starting the adjustment for a predetermined movement speed (usually travel speed) so that a determined unbalance moment and unbalance frequency are applied when the relevant area is reached.

When using a plurality of compacting devices, it is no longer sufficient to store only predetermined zone-specific nominal compaction values, to determine the position association using a triangulation system or GPS, and to store the determined actual compaction values in terms of position correlation (zone-specific) in order to take them into account for a further compaction process. When a plurality of compacting devices are being used, they are usually driven in a row, so that an identical compacting device does not always drive in the area which it has already compacted. In this case, the actual compaction values are preferably transmitted from one device to the other by means of a transmitting and receiving device. Each compacting device therefore preferably also has a system for precise positioning.

The compaction and position data can now be sent directly from one compaction device to another. But a control center may also be used. The region-specific nominal compaction values can preferably be transmitted by radio from the control center to the compaction device. The compaction device then itself sends the actual compaction values associated with the zones. On the other hand, the control center may be used as an intermediate "intelligent tool"; however, it may also be used to store actual compaction values and final values associated with the zones for recording and construction site management purposes.

In addition to determining the compaction value (stiffness), it is of course also possible to additionally determine other values, such as surface temperature and surface damping.

The method for measuring the actual compaction value is explained below based on the use of a so-called vibrating plate. The process for any compaction device is similar.

For absolute measurement, a time-varying excitation force is generated on the vibration unit as a periodic first force directed perpendicular to the surface of the earth with a maximum first oscillation value. The frequency of the excitation force and/or its period is set or adjusted until the oscillating system starts to resonate, which oscillating system consists of an oscillating unit and the ground area to be compacted or measured, which oscillating unit is in constant surface contact with the ground area. The resonance frequency f is recorded and stored. Further, a phase angle * between when the maximum oscillation value of the excitation force occurs and when the maximum oscillation value of the oscillatory response of the oscillatory system described above occurs is determined.

The oscillating mass m of the lower body if, for example, a vibrating plate is being used_dAs is known, the static moment m of the unbalanced exciter_dIt is also known that all oscillation imbalances must be taken into account at this point. The amplitude a of the lower body is measured, as well as the phase angle *. The following relationship enables the oscillation mass m to be determined_d[kg·m]Resonant frequency f [ HZ ]]Static moment M_d[kg·m]Amplitude of A m]And phase angle * [ °]Determination of the Absolute ground hardness k_B[MN/m]：

k_B＝(2·π·f)²·(m_d+{M_d·cos*}/A){A}

The elastic modulus of the relevant ground can be determined according to the hardness k of the ground_BDetermined using the following formula (which is applicable to absolute and relative values):

E_B[MN/m²]＝k_Bform factor

The form factor can be determined by continuum mechanical analysis (continuous mechanical analysis) of the elastic semi-infinite area in accordance with "Forschung auf dem Gebiet des Ingenieuresens" [ engineering field of research ], Vol.10, J.9/10 th 1939, No.5, Berlin, pp.201 to 211, G Lundberg, "elastic Be ü hrung zweier Halbr baume" [ elastic contact between two semi-spaces ].

To determine the relative value, the excitation force is increased until the vibration unit starts to jump up, using this fast method. Furthermore, the excitation force is now no longer allowed to act at an angle perpendicular to the ground surface, but rather the device is automatically moved on the ground surface together with the vibration unit (this applies in particular to the vibration plate) and only has to be traveled in the desired direction by the vibration plate operator. In this case, the measuring device of the device is designed to perform only a frequency analysis of the oscillation response in the vicinity of the vibration plate. A filter circuit is used to determine the lowest harmonic oscillation with respect to the excitation frequency. The lower the lowest harmonic oscillation, the better the ground compaction achieved. The measurement can be further refined by determining the amplitude values of the oscillation responses of all subharmonic oscillations and the first harmonic of the excitation frequency. These amplitude values are related to the amplitude of the excitation frequency by using the following weighting function and using the following equation:

s＝x₀·A_2f/A_f+x₂·A_f/2/A_f+x₄·A_f/4/A_f+x₈·A_f/8/A_f·{B}

x₀，x₂，x₄and x₈Are weighting factors, the determination of which will be described below. A. the_fIs the maximum oscillation value of the excitation force acting on the vibration unit. A. the_2fIs the maximum oscillation value of the first harmonic of the excitation oscillation. A. the_f/2Is the maximum oscillation value of the first harmonic at 1/2 excited oscillation frequency. A. the_f/4And A_f/8Is the second and third harmonicsThe maximum oscillation value of the wave, the frequency of which is one quarter and one eighth of the excitation oscillation frequency, respectively. A. the_2f，A_f/2，A_f/4And A_f/8Is determined from the oscillation response.

The greater the value of s, the greater the degree of ground compaction. This is a very fast measuring method, since all that is necessary for the evaluation of the ground compaction is to determine these maximum oscillation values and the relationship between them, in which a sum is formed.

If the above-mentioned weighting values are determined, an absolute measurement is carried out following a relative measurement, wherein the process of obtaining the absolute value is always associated with one and the same ground component (clay, sand, gravel, clay with a predetermined gravel/sand composition, etc.).

Any degree of compaction increase may be determined if the measurement is made after each compaction process, for example by a trench roller or road compactor or the like. If little or no compaction increase is found, then driving over again will not add any further compaction. If in any case a further increase in compaction is required, a different roller must be used, or the composition of the ground altered by replacement of the material.

Since the apparatus described herein can perform not only absolute measurements, but also rapid relative measurements of ground compaction, it is also possible to perform rapid absolute measurements after calibration, as will be described below. Based on the above equation [ A ]]It is possible to use the information of the "machine parameters", if a vibrating plate is used, i.e. the oscillating mass m of the lower body_dAnd the static moment M of the unbalanced exciter_dAnd a measurement of the amplitude A of oscillation of the lower body, the resonance frequency f [ HZ ]]And phase angle * [ °]Determining the absolute ground hardness k of the ground in the ground sub-area_B[MN/m]。

According to four weighting factors x in equation (B)₀，x₂，x₄And x₈In a corresponding manner, in four different ground subsections of the ground areaDetermining land hardness value k on field_B1、k_B2、k_B3And k_B4And in each case absolute measurements, and in the process the same ground composition should result in different ground hardnesses.

Once ground hardness value k_B1、k_B2、k_B3And k_B4Is determined, the maximum oscillation value A is determined on the same four ground sub-areas_f、A_2f、A_f/2、A_f/4And A_f/8. Substituting the obtained value into equation { B }, using the ground hardness value k_B1、k_B2、k_B3And k_B4S is calculated. This results in four equations from which the four weighting factor values that are not yet known are determined.

If these values are stored in the memory or evaluation unit of the device described below, all that is required when driving through the ground sub-area is to determine the maximum oscillation value a_f、A_2f、A_f/2、A_f/4And A_f/8And associate them with a weighting value to obtain an absolute ground hardness value. The absolute measurement can now be performed as fast as the relative measurement described above.

Relative measurements may also be performed if the geological composition changes; but a recalibration procedure should be performed. The weighted values corresponding to the different geological constituents may be stored in the memory of the apparatus (but typically in the control centre described below) and the measurements may be performed within a predetermined tolerance range for the surface constituents. However, when the geological composition changes, calibration should always be performed in order to obtain sufficient accuracy; in practice, however, calibration may be completed within a few minutes.

The determined ground compaction values are preferably transmitted together with the respective position coordinates of the area being measured and are stored and simultaneously transmitted to a control center, such as a worksite office, in order to make it possible to transmit the data from there to the relevant compaction device again via the transmitting and receiving unit. However, as previously mentioned, the data may also be stored for further processing in the compaction apparatus.

Preferably, a vibrating plate can be used as the compacting means, since this is a low cost product. However, other machines such as trenched rollers and road rollers may be used. But the vibrating plate has an advantage in that its contact area with the ground surface is determined.

Preferably, two imbalances (unbalances) driven in opposite directions are used as excitation forces. The mutual position of the two imbalances must be adjustable relative to one another, so that on the one hand it is possible to ensure that the excitation force is perpendicular to the ground surface (for calibration and absolute measurement) and on the other hand it is possible to tilt the excitation force inwards in a direction opposite to the direction of movement. The frequency of the exciting force, in this case the unbalanced counter-rotational speed, must also be adjustable in order to be able to achieve resonance. The resonant frequency can be manually searched; but can also be done by using an automatic "sweep" process, which starts oscillating at the resonance frequency.

Since the unbalance mass or masses can be moved radially, a static unbalance moment can be created, which is automatically adjusted by the adjustment unit.

The operating frequency of the ground contact unit can also be adjusted by the adjusting unit. If the frequency is adjustable, the resonance of the oscillating system consisting of the ground contact unit and the ground area to be compacted or being compacted can be determined. Resonant operation results in compaction with less compaction power. This oscillating system is a damped system due to the compaction power applied, the degree of damping resulting in a phase angle between the maximum amplitude of the excitation (e.g. the force generated by the rotating unbalanced weight) and the system oscillation (i.e. the oscillation of the ground contacting unit). In order to be able to determine this phase angle, in addition to sensors for measuring subharmonics (measuring resonance frequencies and harmonics), sensors for measuring the time deflection in the direction of the ground compaction are also mounted on the ground contact unit. The time deflection of the excitation (force exerted on the ground contacting unit) can also be measured similarly; but this can also be easily determined from the instantaneous position of one or more unbalance weights. The timing of the maximum amplitude (of the excited oscillation of the ground contact element) is determined by a comparator. The excitation is preferably arranged such that the maximum amplitude of the excitation results in a maximum amplitude of the ground contact unit of 90 ° to 180 °, preferably 95 ° to 130 °. If the excitation frequency is variable, the value determined in this case can be used, as described below, to determine the absolute compaction value.

The maximum amplitude of the excitation force is preferably also adjustable. The excitation force can be adjusted, for example, when two unbalanced weights are used, which rotate at the same rotational speed and whose separation angle is variable. The unbalanced weight may rotate in the same direction or may rotate in the opposite direction.

Furthermore, it should be noted that the occurrence of sub-harmonics can lead to damage of the machine if the compacting apparatus with the ground contact unit is not designed properly. Damping elements are therefore arranged between the ground contacting unit and the rest of the machine to suppress the transmission of sub-harmonics. The entire ground compacting unit may of course be designed such that the low frequency subharmonics cannot cause any damage; their frequencies can be known in practice from the description of the specification. However, it is also possible to reduce the amplitude of the excitation force to such an extent that the amplitude of the sub-harmonics no longer causes damage or is no longer present.

Other preferred embodiments and combinations of features of the invention will become apparent from the following detailed description and the entire patent claims.

Drawings

The accompanying drawings are used to illustrate example embodiments, and in which:

FIG. 1 illustrates an example of a terrain layout having different compacted ground areas;

FIG. 2 shows a schematic view of a vibrating plate for compacting a ground area and measuring the actual compaction values achieved;

FIG. 3 illustrates relevant details of a ground compaction calculation for a pair system ground devices that may oscillate;

FIG. 4 illustrates an example of an implementation of a dimensionless model in the Simulink model;

FIG. 5 shows the movement response of the vibrating plate over floors of different stiffness, with the machine parameters held constant;

FIG. 6 shows a block diagram of a variation of an embodiment of a compaction apparatus according to the invention;

FIG. 7 shows a schematic view of an apparatus layout with multiple compaction apparatuses;

FIG. 8 shows, similar to FIG. 7, a schematic view of an apparatus layout having a plurality of compaction apparatuses and a control center for data transmission and data evaluation;

FIG. 9 is a schematic diagram illustrating a process performed using a system according to the present invention; and

fig. 10 shows a schematic diagram of a system controller.

Basically, identical components have the same reference numerals in the figures.

Detailed Description

An example of monitoring and control of compaction work on a construction site having a plurality of sub-areas TB1, TB2, TB3, TB4 physically spaced from each other will first be described with reference to fig. 9.

At a position whose position coordinates are x1, y1, the absolute compaction value is measured at time t1 using the calibration device EV as calibration value E1(x1, y1) in sub-region TB 1. This data is transmitted from the calibration device EV to the calculation unit R via radio and stored in the calculation unit R. The roller W1 is moved by the system controller to the subarea TB1, the roller W1 first measures the relative compaction value V (W1; TB 1; x1, y1) at the points x1, y1 and sends this value to the calculation unit R. The calculation unit R correlates the relative compaction value of roller W1 with a calibration value E1(x1, y1) and sends the result in the form of, for example, a correction factor K (W1, TB1) ═ corr [ E1(x1, y1) > V (W1; TB 1; x1, y1) ] to roller W1, which then W1 can compact the entire sub-area TB1 to a predetermined absolute compaction value. During this process, it sends the actually achieved relative compaction values V (TB1, xi, yi; i ═ 1.. n) to the calculation unit R, and, as related to E1(x1, y1), these values are also absolute compaction values, which preferably cover an area (i.e. in a predetermined area grid xi, yi, where the index i ranges from 1 to n).

Furthermore, when roller W1 is operating in subarea TB1, roller W2, which is now empty, can be moved to point x1, y1 for driving on the ground there in a non-compacting manner (at time t2), and the relative compaction value V is measured (W2; TB 1; x1, y 1). The relative compaction value is sent to the calculation unit R. If at time t2 the first roller W1 is not yet operating at point x1, y1, the calculation unit R calculates the compaction value obtained by the second roller W2 directly in relation to the calibration value E1(x1, y1) and sends the calculated correction factor K (W2, TB1) corr [ E1(x1, y1) V (W2; TB 1; x1, y1) ] to roller W2. On the contrary, if first roller W1 has compacted location x1, y1 to a predetermined value, the calculation unit performs a correlation calculation between the relative compaction value obtained by second roller W2 and compaction value V (W1; TB1, x1, y 1; t2), i.e. with the post-operative compaction value (═ predetermined nominal value). Since first road roller W1 continuously provides the achieved compaction value V (W1; TB1, xi, yi; i ═ 1.. n) to calculation unit R, calculation unit R can send a suitable correction factor to second road roller W2.

The second roller W2 may then continue to process sub-area TB2 and record the ground treatment process there. Since it has already been calibrated with the measurement at the point x1, y1, it is possible to determine the position-dependent absolute compaction value V (W2; TB2, xi, yi; i ═ 1.. n) in the subregion TB2, even if the calibration device EV is not yet present. When the calibration device EV arrives, it can check whether the required compaction value is reached at the predetermined measurement points x2, y 2. It is not necessary to consider whether or not second roller W2 is moving or stationary, or where. The calibration measurements may be performed independently of this. The calibration device EV then sends the measured absolute compaction value E2(x2, y2) together with the position coordinates x2, y2 to the calculation unit R. Since the calculation unit R knows the measured compaction values of the second roller W2 determined in the subregion TB2, it can again carry out the relevant calculation process and check (based on the measured values of the points x1, y1) that the second roller W2 is calibrated. It immediately sends a correction factor to roller W2, which is now operating in ground area TB 4.

Finally, the calibration device is moved to a third measuring location x3, y3 of the third subregion TB 3. The ground absolute compaction values were determined using the same method as described for TB1 and TB 2.

Thus, calibration measurements at different locations are available for the various sub-regions of the construction site (of course, in this example, multiple measurements may also be made for each sub-region). The system can use these calibration points to calibrate the individual compacting means so that the position of the machine and the corresponding operating state can be taken into account with great freedom. Thus, it is no longer necessary to perform calibration measurements on multiple devices and machine operators at the same location at the same time. The travel distance of the machine may also be minimized. Time shifts can be considered in system planning, which are caused by changes in work or capacity that were not considered at the beginning (because there are more or fewer machine hours available).

As shown in the above example, the compaction values V (W1; TB1, xi, yi; i ═ 1.. n) are stored with the identifier of the machine that measured these values. The computing unit can thus perform subsequent evaluations and, for example, can track the measurement quality of the various devices.

Fig. 10 schematically shows a system controller. Each roller W1, W2, calibration device EV and calculation unit R has a control unit CPU 1. These control units CPU1, were, CPU4 were interconnected with each other and executed programmed programs. This dictates, among other things, which machine records and transmits data, and when this should be done. Furthermore, it is also possible to predetermine and control where the machine should be moved, to which machine the calculation unit sends what kind of data, etc.

When the ground composition to be measured and/or in the ground area to be compacted varies, it is always advantageous to calculate the correlation of the measured relative compaction values with the absolute compaction values. For example, the ground in the various ground areas may be sandy, clay, multi-stone (pebble or gravel); it may also contain different water contents. All of these different geological constituents produce different relative ground compaction values.

If the location and profile of the zones with different geological composition are now known, calibration points with measured absolute surface hardness are predetermined in each of these surface zones. The various ground compacting devices are then moved at this point in order to correlate their relative ground compaction values with the absolute values of the relevant area.

Fig. 1 shows a terrain area 14 with a plurality of ground areas 3 running along a trajectory, which have different degrees of compaction. The higher the compaction value compared to the nominal compaction value, the denser the characteristic shade selected for use herein. The small square pattern indicates that the achieved compaction value already corresponds to the nominal compaction value. The goal of the compaction process desired here (as required in the case of road construction) is to reach a predetermined compaction level, which must not be too high or too low. It is only by the method of the invention that it is possible to achieve a uniform degree of compaction with acceptable effort. As an example, different shading is used here to illustrate the compaction state; however, it is preferable to select display using different colors.

The compaction values of this terrain area are stored, for example, in the computing unit (they may also be stored in any compaction device, so that the compaction device may operate autonomously even if the radio connection to the central computing unit is temporarily interrupted). Furthermore, the geometry (layer thickness, number of layers applied) and material properties (gravel, mix, origin (origin), etc.) can also be stored in the data map.

As an example, a vibration plate 1 is used as the compaction device. Therefore, the vibration plate 1 can be used as a compaction device and a measuring device. Usually, it has a ground contact unit (lower body 5 with bottom plate 4) with two counter-rotating unbalanced weights 13a and 13b (fig. 2) with a total mass m_dThe total mass also includes an unbalanced exciter (energizer). m is_dRepresenting the total excited oscillation mass. On the lower body 5 via a damping element 6 (hardness value k)_GDamping coefficient of c_G) Supporting the static load weight of the upper body 7, having a mass m_f(static weight). The static weight m_fTogether with the damping element 6, results in an oscillating system which is excited at the base point and tuned to a low frequency (natural low frequency). The upper body 7 acts as a second order low pass filter for the oscillation of the lower body 5 during the vibration operation. This minimizes the vibration energy transmitted to the upper body 7.

The ground to be measured, compacted or being compacted in the ground area 3 is a substance that may exist in different models depending on the characteristics being investigated. For the system example described above (ground contact unit-ground), a simple spring damping model (stiffness k) is used_BDamping coefficient of c_B). The spring characteristic takes into account the contact area between the ground contact unit (lower body 5) and the elastic half-space (ground area). In the excitation frequency range of the device described above, which is higher than the lowest natural frequency of the system (ground contact element-ground), the ground hardness k_BIs a static, frequency independent variable. This property mentioned in the present application can be verified in field experiments of homogeneous layered formations.

If the plant and the ground model are organized by taking the links on one side into account in the entire model, the following system of equations (1) describes the degrees of freedom of the associated lower body 5x_dDegree of freedom x of the upper body 7_fDifferential equation of motion.

Based on the link on the side controlled by the ground force, this results in:

F_B＞0

F_B0 others

m_d: oscillating mass [ kg]As a lower body 5

m_f: static load weight [ kg]E.g. upper body 7

M_d: moment of static unbalance [ kg m]

x_d: displacement of oscillating mass [ mm ]]

x_f: displacement of load weight [ mm ]]

Omega: excitation fillet frequency s^-1]Ω＝2π·f

f: excitation frequency [ Hz ]

k_B: hardness of ground area or sub-floor of ground area [ MN/m ]]；

c_B: damping coefficient of ground area or sub-ground of ground area MNs/m]

k_G: hardness of damping element [ MN/m ]]

c_G: damping coefficient of damping element [ MNs/m ]]

The ground reaction force F between the lower body 5 and the ground area 3 to be measured, compacting or to be compacted in this case_BControlling the non-linearity of the one-sided link.

The analytical solution of differential equation (1) is of the following general formula:

1-linear oscillation response, load operation

Periodic lifting (once the machine loses contact with the ground during each firing cycle)

1, 1/2, 1/4, 1/8,. and related harmonics: jump up, fall down, disordered operating states.

* is the phase angle between the time of occurrence of the maximum amplitude value of the excitation force and the time of occurrence of the maximum amplitude value of the oscillation response of the oscillation system.

For the following analysis of "jump-up", assume force F_BActing perpendicular to the surface 2. In contrast, in the case of the vibrating plate described above, this force acts not at right angles to the ground surface 2 but at a rearward angle, for example, in order to produce a forward jumping movement. The perpendicular component of the force with the included angle must be used in the following mathematical analysis. The excitation force acting at an angle to the ground surface is achieved by moving the unbalance weights 13a and 13b, which rotate in opposite directions to one another, so that the unbalance moments added up by the unbalance weights 13a and 13b result in a maximum force vector acting in the lower right direction of 20 ° as shown in fig. 3. To determine this absolute value (resonance), the maximum force vector (and F)_BSame) vertically directed ground surface2。

The solution of equation (1) can be calculated by numerical simulation. The numerical solution algorithm used is essential, especially for verifying chaotic oscillations. For linear and non-linear oscillations, a good approximation solution and fundamental properties related to the bifurcation of the fundamental frequency can be obtained by using analytical calculation methods, such as averaging. The average theory is described in the VDI conference report, volume 4, volume VDIVerlag Dsseldorf, Andregg Roland (1988) "Nichtlineare Schwingungen bei dynamischen Bodenverdichter" [ non-linear oscillations in dynamic ground compaction devices ]. This allows a good overall view of the emerging solutions. The analytical method is associated with the irrational high complexity of multi-branch systems.

Using Mathlab/Simulink^®The package acts as a simulation tool. Its graphical user interface and available tools are well suited to address current problems. Equation (1) is first converted entirely into a dimensionless form in order to obtain results that are as universally as possible.

Time: τ ═ ω₀t；

Resonance ratio:wherein omega is 2 pi.f

I.e. K ═ f/f₀And wherein f is the excitation frequency, f₀Is the resonance frequency [ Hz]。

ω₀Is the fillet resonance frequency [ s ] of a "machine-ground" oscillating system^-1]。

Position:amplitude A₀f can be varied freely.

Material characteristics:

mass and force:

wherein:

mathelab Simulink was used^®The resulting equation (3) is graphically modeled with reference to fig. 4. Non-linearities are considered in simplified form as pure force control functions and are modeled using the "Switch" block in the Simulink library.

The coordinate system used in equations (1) and (3) includes the natural weight (static load weight m)_fOscillating mass m_d) The resulting static lower zone. When comparing with the measurement integrated with the acceleration signal, the static low region has to be subtracted in the simulation result for comparison purposes. The initial conditions for the simulation are all set to "0". Referring to the results of the steady state, "ode 45" (normal-Price) having a variable integrated step width (maximum step width of 0.1 second) was selected as a solving method in a period from 0 second to 270 seconds.

For analyzing the disordered machine response of the vibrating plate 1, it is usually sufficient to investigate the oscillating portion. In particular, in the case of well-matched rubber damping elements, the dynamic forces in these elements (upper and lower bodies) are negligibly small compared to the static forces, andthis is true. In this case, two equations (1) and (3) can be added, one degree of freedom x for the oscillatory element_d≡ x, equation (4a) results. The correlation analytical model is shown in fig. 3.

F_BIs the force acting on the ground area; refer to fig. 3. This conventional second order differential equation is rewritten to form the following two first order differential equations:

whereinAndas a non-linearity of the ground force control.

In this case:

using X₁(t)-X₂(t) represents the phase space, derived therefrom

The phase curve, also called the orbit, is a closed circle or ellipse in the case of linearity, steady state and single frequency oscillation. In the case of nonlinear oscillations in which other harmonic oscillations occur (the scraping surface periodically rising from the ground), this harmonic can be considered as a modulation period. Only at period doubling, i.e. subharmonic oscillations (as "beating" to make an initial circular motion) become closed curves with intersections in the phase space representation.

It has been found that sub-harmonic oscillations in the form of branches or branches are further central elements of highly non-linear and chaotic oscillations. Unlike harmonics, subharmonic oscillations represent a new operating state of the nonlinear system, which must be dealt with separately; this operating state is very different from the original linearity problem. This is because the harmonics are small relative to the fundamental, i.e. mathematically, the nonlinear solution of the problem is close to the solution of the linear system.

In practice, the zero-crossing detection can be performed by a Ho for the oscillating wavePulses of a hall probe (Hallprobe) initiate recording of the measured values. This also allows the generation of Poincar é graphs. If the periodically recorded amplitude values are plotted as a function of a changeable system parameter, in this case the ground hardness k_BThis results in branching (bifurcation) or so-called fig tree diagram (fig. 5). On the one hand, this figure shows the behavior of an amplitude which suddenly becomes very large in the region of the branching points as the stiffness increases, wherein the tangents of one or more relevant curves run vertically at the branching points. There is thus no need in practice to provide any additional power to jump up the roller. This figure also shows that as hardness increases (compaction), there is a relative increase in hardness k_BMore bifurcations occur at shorter time intervals. These diverging waterfalls produce new oscillatory components whose frequencies are half of the previous lowest frequencies in the spectral range. Since the first branch starts at the fundamental wave with frequency f and period T, the resulting waterfall-like branches have frequencies f, f/2, f/4, f/8, etc. The fundamental wave also similarly generates subharmonics, forming a continuum of frequencies in the low frequency range of the single spectrum. This is similar to the behavior of chaotic systems, i.e. in the present case of vibrating plates.

It should be noted that the system of compaction apparatus is in a deterministic state rather than a random chaotic state. Since all parameters that cause the disordered state cannot be measured in their entirety (cannot be observed in their entirety), the operating state of the subharmonic oscillations cannot be predicted for the actual compaction process. In practice, the operational response is also characterized by a large number of unpredictable factors, the machine may slip due to the loss of a large amount of contact with the ground, and low frequency oscillations may cause the load of the machine to become high. Furthermore, the divergence of the machine response may occur all the way out (unintended), thereby immediately causing a major additional load. High loads also occur between the scraping surface (damping) and the ground, which can lead to undesired loosening of the ground substrate close to the surface and to particle damage.

In the case of new devices whose machine parameters can be actively controlled according to measured variables, such as ACE, the amann proportion Expert, it is possible to immediately reduce the unbalance and thus the power supply when the first harmonic oscillation occurs at a frequency f/2. This measure reliably prevents the scraping surface (scraping) from jumping or falling off undesirably. Furthermore, the amplitude and frequency of the compacting device are mechanically controlled by the action force, which ensures a control of the non-linearity, thereby reliably preventing a jump/fall, which actually or eventually is a result of the non-linearity occurring.

Due to the fact that the subharmonic oscillations in each case represent a new state of machine movement, for example in order to record the state of compaction of the ground, the relative measurements need to be recalibrated with reference to a test procedure (e.g. pressure plate test-DIN 18196) for each newly occurring subharmonic oscillation. This correlation measurement is not required, as will be explained below.

In the case of a "compactometer" in which the ratio of the first harmonic 2f to the fundamental f is used for compaction monitoring, the correlation changes radically when a jump-up occurs; the linear relationship between the measured value and the ground hardness exists only in the respective branch states of the movement.

If the machine parameters remain unchanged, the cascading of forks and harmonics (where their associated period doubles) can similarly be used in large rollers as an indication of increased ground hardness and compaction (relative compaction monitoring).

When rollers (from road rollers to manually operated trench rollers) use the rolling displacement of the scrapers for their forward movement, and therefore there is no direct relationship between vibration and forward movement, the diaphragm is always controlled to periodically lift off the ground to move forward by tilting the directional oscillator of the diaphragm. The vibration and forward motion are thus directly coupled together and therefore the platen and punch always have a non-linear oscillatory response. Then when the hardness k is_BWhen added, these devices enter the region of double the cycle more quickly and with them the disordered operating state occurs more frequently than in the case of rollers.

According to the above description, a sensor for recording the oscillation form of the oscillation system is arranged on the lower body 5 or the upper body 7. The effect of the oscillations generated by the damping element as described above cannot be neglected if it is arranged on the upper body 7.

The device 1 can be moved over a ground area 2 in order to compact the ground area 3 in this case, as an example, the device 1 can have an unbalance unit 40, an adjustment unit 41, a timer 43, a comparison unit 45, a measuring unit 47, a storage unit 49, a positioning unit 51 and a transmitting and receiving unit 53. These functional blocks are schematically shown in fig. 6.

The unbalance unit 40 has an adjustable unbalance moment and an adjustable unbalance frequency. The adjustment or setting is performed by an adjusting unit 41, which adjusting unit 41 is mechanically connected to the unbalancing element 40. The positioning unit 51 is connected to the storage unit 49 to transmit signals. The positioning unit determines the position of the ground area 3 being compacted. The position, i.e. the position coordinates, can be determined triangularly by means of a position finding or with GPS. By way of illustration, the measuring unit 47 in this example is arranged on the base plate 4, which is connected to the comparing unit 45 and the memory unit 49 for transmitting signals. According to the above description, the measuring unit 47 automatically determines the actual compaction value of the ground area 3 being compacted. This ground compaction value is stored in the storage unit 49 together with the position coordinates determined by the positioning unit 51 as an area-specific actual compaction value. The respective region-specific actual compaction values are compared with the region-specific nominal compaction values associated therewith using the comparison unit 45, so that region-specific imbalance values or imbalance frequency values are obtained, corrected by the adjustment unit 41 and subsequently compacted by driving over the region. The comparison unit 45 is connected to the measurement unit 47, the storage unit 49 and the timer 43 to transmit signals.

The calculation unit 50 includes a timer 43, a comparison unit 45, a storage unit 49, and a central processing unit 52. The calculation unit 50 is also connected to a sending and receiving unit 53 and a positioning unit 51. The calculation unit 50 uses the stored and transmitted data to perform all calculations to set the corresponding machine data for optimal compaction. It also makes data available for transmission to a control center or other compaction device.

The adjustment unit 41 uses the timer 43 to make this value available at the correct time for adjusting the unbalance moment and unbalance frequency. In particular, in this case, the mass block needs to be moved, accelerated, and decelerated. This all takes time. The timer must therefore predetermine the set values of the moving direction and the moving speed.

The data receiving and transmitting unit 53 serves to receive the region-specific nominal compaction values, in particular the region-specific actual compaction values from a preceding compaction process. The data receiving and transmitting unit 53 is also used to transmit the region positions and their actual compaction values determined during the compaction process. The data receiving and transmitting unit 53 is connected to the storage unit 49 for transmitting signals, by means of which signal transmission links to the comparison unit 54 and the measurement unit 47 are established, and via the timer 43 to the adjustment unit 41.

The compaction process described above has been described based on a vibrating plate, merely by way of example. Of course, any type of roller and punch may be used instead of the vibrating plate.

In the case of a vibration plate, the direction of the travel adjustment unit is provided only by operating a guide shaft (guide flap). For some types of roller, the direction of travel is typically set by the steering wheel.

Similar to terrain area 14, fig. 7 shows a terrain area 60 that is compacted or desired to be compacted using two schematically illustrated rollers 61a, 61b and a vibratory deck 63. The road rollers 61a and 61b and the vibration plate 63 each have positioning units 65a to 65 c. Communication between these three devices 61a, 61b and 63 for data transmission of the actual compaction values specific to the respective zone takes place from device to device, schematically illustrated by the double-headed arrows 67a, 67b and 67 c. By way of further illustration, the terrain area 60 includes faults 69 as areas that cannot be compacted. One of the three devices 61a, 61b and 63 tries to compact the fault 69 and will subsequently detect a zone-specific actual compaction value which is lower than the zone-specific nominal compaction value. This actual compaction value is sent to the other two devices along with their respective position coordinates and stored in the device that is performing the compaction work. During the subsequent compaction process, the same device or one of the other devices, it is found that the region-specific actual compaction value cannot be increased within a predetermined tolerance value during another compaction process. This fault 69 will be excluded from the recompacted area because it cannot be compacted, i.e. the compacting device will not be driven over it. If it is not possible to avoid driving over an adjacent area for compaction, the driving over the fault 69 accelerates and reduces the compaction force (only to level the surface). A similar approach is also used for regions that have reached a predetermined region-specific actual compaction value.

Fig. 8 shows a modification of the arrangement of the apparatus in fig. 7. In fig. 8, there is a control center 70, with which all compaction apparatuses, in this case, again by way of example, a vibrating plate 63 and two rollers 61a and 61b, communicate with one another via their data receiving and transmitting unit 71. The control center 70 is typically a so-called worksite office that collects all of the information. The compacting devices 61a, 61b and 63 then transmit the zone-specific actual compaction values to the control center 60, which are suitably collected and evaluated in the data storage 73. Similar to fig. 1 (but with a more uniform compaction value), a terrain area is then created in the control center 60 from which the achieved compaction value can be seen. In a display such as this, the fault 69 is very noticeable. The control center 70 then takes action by replacing the ground material there.

In the above description, the ground area has been compacted. However, a covering applied to an area of ground, such as an asphalt covering, may also be compacted in a similar process using the same compaction device.

In summary, it can be stated that the present invention has provided a system with new capabilities for efficiently managing a construction site.

Claims (21)

1. A system for collaborative ground processing, comprising:

a) a plurality of compacting devices (W1, W2) for compacting the ground, wherein the plurality of compacting devices (W1, W2) are designed to determine a position-dependent relative compaction value (V (W1; TB1, xi, yi; i-1.. n)),

b) calibration means (EV) for determining a plurality of position-dependent absolute compaction values,

c) a calculation unit (R) for calculating a correlation between a plurality of position-related relative compaction values and a plurality of position-related absolute compaction values, wherein the plurality of compaction devices (W1, W2), the calibration device (EV) and the calculation unit (R) are connected to each other for transmitting information, and

d) a system controller (CPU1,.., CPU4) which is designed to continuously send the plurality of position-dependent relative compaction values and the plurality of position-dependent absolute compaction values of the plurality of compaction devices (W1, W2) to the calculation unit (R) and these values are stored in the calculation unit (R), if a plurality of compaction values of the same position exist, a plurality of compaction correlation values are calculated and sent to the plurality of compaction devices and stored as correction values in the plurality of compaction devices.

2. The system of claim 1, wherein the system controller is configured such that each compaction device is assigned an identifier, and a plurality of position-dependent relative compaction values are stored in the computing unit together with the identifier.

3. The system according to claim 1 or 2, wherein the computing unit is designed to store a ground area map.

4. A system according to any one of claims 1 to 3, characterized in that the calculation unit is designed to relate the position-dependent relative compaction value to the processed characteristic values of the ground layers.

5. System according to any one of claims 1 to 4, characterized in that the calibration device and the compacting device are equipped with GPS devices for positioning.

6. System according to any one of claims 1 to 5, characterized in that the calibration device is in the form of a compacting device, in particular a roller.

7. System according to any one of claims 1 to 6, characterized in that it has a plurality of compacting means without calibration means.

8. Method for compacting at least one ground area (3) or at least one covering area applied to the ground area to a predefined area-specific nominal compaction value, wherein position coordinates of each area are determined during a first run, and a device compaction value corresponding to the area-specific nominal compaction value is automatically set, an area-specific actual compaction value is automatically determined during the run, and the area-specific actual compaction value is automatically compared with the area-specific nominal compaction value, the device compaction value is readjusted, the area-specific actual compaction value is stored together with the position coordinates and is transmitted to at least one further compaction device (61a, 61b, 63) and/or in particular to at least one control center (70), and the last run-through area-specific actual compaction value is received by at least one further compaction device (61a, 61b, 63) and/or in particular by at least one control center (70) The actual compaction value and/or the nominal compaction value can be used for a previously automatic adjustment of each region-specific device compaction value for a possible subsequent compaction process, so that the respective corresponding device compaction value is set region-specifically without intervention by the driver of the compaction device, so that the driver can focus his attention entirely on driving the compaction device.

9. The method of claim 8, wherein the ground reaction force F is automatically calculated and adjusted_BAnd a phase angle * as a zone specific compaction value, wherein the phase angle * is the maximum ground reaction force F at right angles to the surface of the ground zone_BAn angle with a maximum oscillation value of an oscillation response of an oscillating system constituted by the ground area and an oscillating unit of the compaction device performing the compaction.

10. Method according to claim 8 or 9, characterized in that the compaction value for each zone (3) is sometimes automatically available before the zone (3) is driven over, wherein the time interval is automatically selectable so that the compaction value is automatically set when each zone (3) is reached.

11. The method according to any one of claims 8 to 10, characterized in that position coordinates of the respective regions (3) involved in the compaction process are determined, and that the determined region-specific actual compaction values of the respective regions (3) are stored together with the position coordinates of the respective regions so as to be available for a previous automatic adjustment of each region-specific compaction value for a possible subsequent compaction process.

12. The method as claimed in any of claims 8 to 11, characterized in that the region-specific compaction values determined while driving through the region are transmitted to at least one further compaction device (61a, 61b, 63) and/or in particular at least one control center (70), wherein the region-specific actual compaction values and/or nominal compaction values previously driven over are received by the at least one further compaction device (61a, 61b, 63) and/or in particular by the at least one control center (70).

13. Method according to any one of claims 8 to 12, characterized in that the respective region-specific first actual compaction value or the respective region-specific nominal compaction value of the last previous compaction process is compared with the region-specific actual compaction value measured while driving through compaction, a region-specific compaction difference value is determined, this compaction difference value is compared with a predetermined tolerance value, and if the compaction difference value is less than or equal to the tolerance value, the compaction value is set when driving through the region again such that no further compaction takes place and the compaction device (61a, 61b, 63) is driven through the relevant region (3) only for leveling the surface.

14. A method according to any one of claims 8 to 13, characterised in that a route travelled over the area is displayed in advance to a driver of the apparatus over which the compaction apparatus must travel in order to compact a plurality of areas within an optimum period of time and minimise the number of unnecessary journeys over the area.

15. A compacting device (61a, 61b, 63) for compacting at least one ground area (3) or at least one covering area applied on a ground area to a predetermined area-specific nominal compaction value, in particular for use in a system according to claim 1, the compacting device comprising:

a) a driving direction selection unit by means of which the device driver can control the direction of travel while driving through the zones (3),

b) a storage unit (49) for storing the area-specific compaction values,

c) a calculation unit interacting with the storage unit (49) in order to determine a device compaction value from the compaction value,

d) at least one compacting unit (40) having an adjusting unit (41),

e) wherein the adjustment unit (41) interacts with the calculation unit in order to set a device compaction value, having a positioning unit (65a-c) for automatically determining the position coordinates of the individual regions (3) awaiting compaction,

f) a measuring unit (47) for automatically determining the actual compaction values specific to the respective region,

g) a comparison unit (45) for comparing the respective region-specific actual compaction values with the associated region-specific nominal compaction values,

h) a data receiving and transmitting unit (53) which is connected to the adjusting unit (41) and in particular to the comparison unit (45) for transmitting signals for receiving a region-specific nominal compaction value and a region-specific actual compaction value from a preceding compaction process, and for transmitting the positions of the regions (3) and their actual compaction values determined during the compaction process, in order to automatically obtain a region-specific device compaction value corrected by the adjusting unit (41) for carrying out a compaction process subsequently or immediately over the region, as a result of which the device driver only has to monitor the direction of travel and not to set a compaction value.

16. A method of operation of the system of claim 1 for creating a compacted ground area having the steps of:

a) the compaction device is moved over at least one subregion of the ground region, the compaction device determining at least one position-dependent relative compaction value when moving over the region,

b) determining a position dependent absolute compaction value in the sub-area using a calibration device,

c) automatically sending information about the relative and absolute compaction values related to the position determined in step a) and step b) to a calculation unit,

d) determining at least one correlation value between the relative and absolute compaction values,

e) automatically sending the correlation value to the compaction device, an

f) Readjusting the reference value of the compacting device, if necessary, according to the transmitted correlation value.

17. Operating method according to claim 16, characterised in that the position-dependent absolute compaction value is first determined and the compacting device is subsequently moved over the partial region in a non-compacting manner in order to determine at least one position-dependent relative compaction value when moving over the region.

18. Operating method according to claim 16, characterised in that the compacting device is first moved in a compacting mode over the partial region, at least one position-dependent relative compaction value is determined while moving over the region, and a position-dependent absolute compaction value is determined later.

19. Operating method according to claim 16, characterised in that a further compacting device is used as the calibration device and is designed to determine not only a relative compacting value but also an absolute compacting value.

20. Method of operation according to any of claims 16 to 19, wherein a plurality of sub-areas are driven over by the compacting device and a further compacting device.

21. Operating method according to any one of claims 16 to 20, characterised in that data relating to the formation structure, in particular material and formation thickness, are stored in the calculation unit and these data are associated with the compaction value.