DE9320538U1 - Arrangement for creating a cadastre of elongated cavities located below the earth's surface - Google Patents

Description

Maschinenfabrik Scharf GmbH Römerstrasse 104, 59075 Hamm

Arrangement for the creation of a cadastre of elongated cavities located below the earth's surface

The invention relates to an arrangement for creating a cadastre of elongated, essentially horizontal cavities located below the earth's surface, which can be walked on or not.

A variety of influences can lead to positional deviations in long underground cavities, particularly in the form of sewage canals, pipes and lines. Precise knowledge of these deviations is a prerequisite, for example, for choosing a suitable renovation or renewal process. Only through regular inspections is it possible to obtain a complete and up-to-date overview of the respective cavity network and its condition.

Telephone (0234) 51957/58/59 ■ Fax (0234) 51 0512 Commerzbank AG Bochum, Account No. 3 864 7^2* *( &rgr; LZ^e 400 g6}· Vfcistgiu

Telex 825361 swopd &igr; Essen, account number 7447-431 (bank code 36010043)

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In the case of accessible cavities, the horizontal and vertical position deviations can be measured using the stationary optical methods known from engineering surveying.

In the non-accessible nominal diameter ranges, measuring instruments or systems such as inclinometers and pressure-measuring hose scales are used to determine vertical deviations or lasers to determine vertical and horizontal deviations. In all three methods, a distance or path measurement is also required.

However, monitoring should be carried out at regular intervals to ensure that all systems in a cavity network are operating properly. Documentation is also desirable.

Inspections are currently limited to optical methods, i.e. visual inspection in accessible cavities or sewer mirroring, sewer television inspection and sewer photography in non-accessible cavities. However, these methods can only qualitatively record the majority of types of damage. Quantitative recording and in particular the assessment of the tightness of individual pipe connections, pipes or supports is only possible in exceptional cases. However, this knowledge is required for determining the time and the choice of maintenance measures, so it appears necessary to change the current inspection practice and supplement it with suitable measuring and testing methods. For this purpose, a suitable determination of the position of the cavity in question would be particularly desirable.

The quantitative recording of the actual condition of cavities formed by sewer channels, pipes and lines

is currently not widely practiced. This is due, among other things, to the fact that there are relatively few suitable measuring devices and systems on the market that, for example, enable continuous measurement in combination with remote sewer inspection. The need for an inspection arises, however, from the general duty of care and the regulations for sewer operators. Defective sewers require immediate action to avoid regulatory and liability consequences.

Only through proper inspection and documentation is it possible to obtain an overview of the current status of sewer systems in particular or of changes to it and, based on this, to develop technically sensible and economically viable strategies for their maintenance.

The journal "Das Markscheidewesen" 90 (1983) No. 3, pp. 252-258 describes the continuous geometric monitoring of vertically arranged shaft guidance systems using inertial navigation.

Based on the state of the art, the invention is based on the object of creating an arrangement which enables an accurate and reliable determination of the position of essentially horizontally extending cavities in the form of, in particular, sewer channels, pipes and lines in the accessible and non-accessible nominal width range, which allows a sewer television inspection with simultaneous distance and path measurement and which allows the transfer of the determined data to the cadastre.

To solve this problem, the actual spatial position of the longitudinal axis of an essentially horizontal cavity is determined by means of a sensor mounted on a

The position is continuously determined by an inertial navigator in the form of a gyrocompass system arranged on the measuring carrier. The measuring carrier moves in the longitudinal axis of the cavity or parallel to it. The gyrocompasses of the inertial navigator are coupled with accelerometers for measurement purposes and provide their orientation. The determined data are recorded with the help of an integrated recording unit. The position coordinates can be determined from this. This can be done immediately during recording, with the position coordinates then also being recorded on a data carrier carried along. Of course, direct radio transmission to an above-ground receiving station is also conceivable. However, the recorded data is usually evaluated after an inspection trip in an above-ground evaluation and display unit. This has the necessary hardware and software.

Mechanical gyroscopes or laser gyroscopes can be used. In addition, the measuring carrier can be equipped with an automatic cross-section measuring device, for example an ultrasonic cross-section measuring device.

The arrangement according to the invention is therefore based on the principle of inertial navigation. This requires three gyro axes and three acceleration axes. Control is carried out by a reference method that is independent of external devices and that obtains an acceleration measurement value from the inertial force that occurs when the measuring carrier accelerates, from which the speed and the distance covered can be determined by integration. For navigation in space, measurements in all three spatial directions are necessary. The spatial direction reference is obtained independently of the movement of the measuring carrier by a gyro platform on which the accelerometers are mounted. The gyro platform is a

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gimbal-mounted frame in which gyroscopes are mounted, each with one degree of freedom. The gyroscopes are used to determine the rotational movements of the platform in the spatial coordinate system and correct them using actuators controlled by the gyroscopes, so that the platform maintains its position in space.

To improve accuracy, external reference values can be used at certain intervals to correct (update) the calculated values.

The method can be supported by simultaneous observation of the channel using a television camera and additional cross-sectional measurement of the channel. The measurement accuracy can be improved by using a second reference point, for example in the target shaft.

After a predetermined length of the cavity to be examined has been recorded, the recorded and stored measurement values are fed into an electronic evaluation and display unit. In this evaluation and display unit, the data obtained are processed so that they can be entered into a register. The further processing and processing of the recorded data then takes place on graphic data processing systems (using screens, printers and plotters).

All components of the measuring carrier and the measurement value recording, which includes at least the inertial navigator, i.e. an entire channel inspection unit, can be designed to be explosion-proof, so that it can also be used in potentially explosive areas.

The invention is explained in more detail below using an embodiment illustrated in the drawings. They show:

Figure 1 shows a vertical cross-section of a section of a sewer network with a movable measuring carrier therein;

Figure 2 is a plan view of the representation of Figure 1 as per arrow II and

Figure 3 shows a diagram of an electronic evaluation and display unit.

In Figures 1 and 2, 1 designates a sewer. The sewer 1 is connected to the earth's surface 4 via vertical access shafts 2, 3.

To determine the actual spatial position of the longitudinal axis 5 of the sewer 1, a measuring carrier 6 is used, which is guided in the sewer 1 in the longitudinal axis 5 or parallel to the longitudinal axis 5. The guide can consist of a rail not shown in detail in the drawings. However, it can also be formed by the wall of the sewer 1 itself. It can be a sliding or rolling guide.

An inertial navigator 7 is installed on the measuring carrier 6 and is connected for measurement purposes to a data storage device 8 which is also provided on the measuring carrier 6.

A television camera 9 is provided on the front side of the measuring carrier 6. The television camera 9 can be coupled to a recording device in the measuring carrier 6. However, a direct connection via a cable (not shown in more detail) to a cable (not shown in more detail) is also conceivable.

illustrated observation unit on the earth's surface 4. Furthermore, the use of a cross-sectional measuring device, not shown separately here, is planned.

To create a cadastre of the sewer 1, a reference point BP is first fixed in position in the area of the access shaft 2. When the measuring carrier 6 is moved from this reference point BP, the respective position coordinates of the longitudinal axis 5 of the sewer 1 are determined and recorded on the data storage device 8. Radio transmission to the surface is also possible. The cross-section of the sewer 1 is recorded in parallel.

After a predetermined length of the sewer 1 has been traveled, which lies for example between the access shafts 2 and 3, the recorded and stored measurement values are fed to an electronic evaluation and display unit 10. This comprises a computer 11 and software for evaluating the measurement values recorded on the data storage device 8 by the inertial navigator 7. Furthermore, the evaluation and display unit 10 is assigned a monitor 12 and a computer 13 for processing and storing the measurement data. Finally, the evaluation and display unit 10 also has a plotter 14 for creating a sewer cadastre.

Reference symbol division

1 - Sewer

2 - Exnstxegschacht

3 - Exnstxegschacht

4 - Earth's surface

5 - Longitudinal axis &ngr;.

6 - Measuring carrier

7 - Inertial Navigator

8 - Data storage

9 - TV camera

10 - Evaluation and display unit

- Computer - Monitor - Computer - Plotter

BP - Reference point

Claims (1)

Claim for protection Arrangement for creating a cadastre of walkable and non-walkable elongated, essentially horizontal cavities (1) located below the earth's surface (4), in particular sewage pipes, tubes or canals, in which the spatial actual position of the longitudinal axis (5) of each cavity (1) can be continuously determined from a positionally fixed reference point (BP) by means of an inertial navigator (7) arranged on a measuring carrier (6) guided in the cavity (1) in or parallel to the longitudinal axis (5), and the measured values thus determined can be transferred to a data storage device (8) also carried by the measuring carrier (6), wherein at least one inertial navigator (7) is installed on a measuring carrier (6) guided in a sliding or movable manner in a cavity (1) to be monitored and is connected for measurement purposes to a data storage device (8) also provided on the measuring carrier (6), which in turn is connected to an electronic display and evaluation unit (10) and that at the same time as the actual spatial position of the longitudinal axis (5) of a cavity (1) relative to the reference point (BP) is determined, the cavity (1) can be inspected by means of a television camera (9).