CA2270483A1

CA2270483A1 - Mining or tunnelling survey system and method of operation

Info

Publication number: CA2270483A1
Application number: CA 2270483
Authority: CA
Inventors: James Gary Hubley
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-04-30
Filing date: 1999-04-30
Publication date: 2000-10-30

Abstract

A mining or tunnelling survey system and method are provided, which use two rods connected to a mine or tunnel wall as part of line and grade layout and also to establish, by means of a light beam, a reference line ending with a dot on the face of the mine or tunnel heading. A calculator, total station instrument or computer with suitable software is employed to lay out and record the obtained data that can then be used for subsequent analysis, for example, by means of an AutoCAD program, outside of the mine. All operations can be performed by the same surveyor.

Description

MINING OR TUNNELLING SURVEY SYSTEM
AND METHOD OF OPERATION
BACKGROUND OF THE INVENTION
This invention relates to a mining or tunnelling swvey system which can be operated by one surveyor and to the line and grade in a mine or tunnel.
The customary mining procedwe requires two people to hang the lines and shoot the line and grade in mine heading developments or tunnelling operations.
Heavy equipment is also required to get to the back of the heading, hang the lines and shut ventilation dampers. Then, one person shoots the line and grade, while the other marks the spot on the face. Traditionally, the line and grade is established by line plugs and grade plugs every 200 feet (60 meters) in development headings of the mine or tunnel. Such operation is inefficient, labow-intensive and may compromise the safety of the surveyors.
An improvement to the above procedwe has been proposed in U. S. Patent No.
4,446,626 which uses a focused beam transmitter suspended from spads set in the ceiling of the mining tunnel to establish a visible light beam aligned with the desired directional heading of the tunnel. The light sowce is attached by suitable suspension means to the ceiling of the mine. This is usually a difficult procedwe requiring heavy mining equipment. No simple procedwe is provided in this patent to install a grade line in the mine in addition to the heading line.
OBJECTS AND SUrMMARY OF THE INVENTION
It is an object of the present invention to obviate the disadvantages of the prior art and to provide a system and a method for mine surveying that can be carned out safely and efficiently by one person.
Other objects and advantages of the invention will be apparent from the following description thereof.
The present invention provides a survey system, including both a novel apparatus and a method, for establishing a line and a grade in a mine shaft, or the like, (hereafter "tunnel") using a beam of light aimed at an excavation face of the tunnel. In this system a sowce of light directs a beam of light along a reference line that has a predetermined relationship to a desired line and grade.
The apparatus of this invention comprises means for establishing a light beam initially and for relocating it as it is required from time to time along such a reference line. A light sowce is mounted in a light fixtwe secwed to an interior wall of the tunnel. The light fixture includes adjustment means with sufficient degrees of freedom to permit adjustment of the light sowce to direct a light beam along the reference line. A sight means may help align the light sowce. A sight means is mounted on a sight fixture secwed to an interior wall of the tunnel. The sight fixture includes adjustment means with sufficient degrees of freedom to permit adjustment of the sight means to locate it on the reference line. To facilitate re-establishment of the location of the light sowce and sight means, should they be moved, a light sowce reference point and a sight reference point are secured on an opposite interior wall, each on a line intersecting and perpendicular to the reference line and, respectively, extending through one of the light sowce and the sight means.
The method of this invention permits a single swveyor to establish and use the apparatus of this invention. A surveyor, having a known reference point and information locating the reference line with respect thereto, can, with a known swveyor's instrument, locate the light fixtwe point, the sight fixtwe point, the light sowce reference point and the sight reference point within the tunnel. The position of these fixtwe points will be determined by the location of the reference line in relation to the tunnel interior, available sight lines, the extent of adjustment provided by the adjustment means of the light and sight fixtwes and safety and work area considerations. It is preferred that the swveying instrument have the known capabilities of being programmable, of enabling spherical geometry calculations and of enabling an operator, holding a known prism device or the like at a position remote from the instrument, to locate a point on a line of sight of the instrument.
Once these points are located, the light sowce and sight fixtwes may be assembled and secured to the tunnel wall and the light sowce and sight points established by a reflector on the opposite wall. The surveyor then positions the light sowce and the sight means on the reference line using the adjustment means and directs the light beam using the sight means along the reference line to the excavation wall. The surveyor has thus established a visible yet unobtrusive reference line from which suitable measurements may be taken to mark out the portion of the excavation wall to be mined.
For ease of assembly and calculation, it is preferred that the fow points in the interior of the tunnel wall, as described above, are located in an imaginary flat plane that is level transversely and contains the reference line longitudinally. In other words, the light fixture is level with and opposite to the light reference point; the sight fixtwe and the sight reference point similarly so, but each pair of opposing points are parallel to the reference line.
The fixtures, including the adjustment means, are capable of many constructions to obtain the functions required this invention. The particular construction may depend upon the natwe of the tunnel and the materials of the tunnel walls. It is preferred, however, for tunnelling in rock, that the light fixtures each comprise a bracket, which may be bolted or otherwise secwed to a rock wall, a rod connection means linked by a joint means to pivot on the bracket, a locking means to fix the position of the joint at a desired alignment, a rod of a predetermined length fitted and secwed to the rod connection means, and a light fitting secured to a distal portion of the rod to receive a light sowce. The sight fixture is similarly constructed but with a fitting to receive the sight. In each case the length of the rod is that required to span the distance to place the light sowce or the sight on the reference line. In practice the rods may be cut on site to the correct length.
In preferred embodiments a light beam sowce such as a diode or laser may be used and the fitting to receive the light sowce is jointed to permit the light sowce to be aimed and directed along the reference line; both gross and fine adjustment controls may be preferred as well. A sighting device, such as a simple washer, may be sufficient for some pwposes, but it is preferred that the sight have a large swrounding surface to permit an operator to aim the light through the sight more easily.
The light beam may be aimed at the outer surface of the sight with gross adjustments and then aimed through the sight with fine adjustments.
The beam projects to a position on the excavation face of the mining tunnel on the determined reference line of the heading. The swveyor can paint the light beam spot on the face, and then mark the face for surveying purposes. After rock is removed the light beam spot may be marked again on the new face and the reference line re-established on the face for further mining. In this regard, the nature of this invention permits the surveyor to disassemble the light and sight fixtures (but the brackets would probably be left on the wall) to clear the tunnel during the excavation work. Then when a new line is required anyone, even a person not trained in survey work, can reassemble the fixtures to the bracket and level and align each to its opposite reference point; a light source can be placed in the light fitting and aimed at the sight surface, then into the sight, to project the new reference line.
The fixtures can be readily installed and used by one surveyor, usually in less than one hour, and without bringing heavy mining equipment or shutting off the ventilation. During this procedure, other mining activities may continue because ventilation is uninterrupted. The surveyor sets up the transit at a known point with a known backsight, using conventional survey techniques. He then picks a suitable location for the fixtures. Installing the grade rods is easier than installing the customary line and grade plugs, because the surveyor does not need to interfere with the miners working in the heading. The installation is completed and checked before leaving the heading To locate the position of the light fixture the surveyor places a prism as close as possible to desired spot on the wall. The instrument then directs the surveyor to move the prism until it is on the line of sight. The spot may then be marked for identification. The data (azimuth, horizontal distance, vertical distance and offset) is measured. A calculation may then be done, preferably in a computer located on site, such as in the surveying instrument, to determine by means of a computer program a theoretical elevation (z) for a point on the reference line that is level with and perpendicular to the spot located by the surveyor with the prism.
The surveyor then measures up or down to the theoretical elevation (z) of the grade line. A hole is drilled and a quick bolt is installed. The prism is then attached to an adjustable mount on the quick bolt and the data is recorded. The adjustable mount is adjusted until ~z = 0, then the data is recorded.

The next fixture is approximately 5 meters distant from the first fixture. The procedure is repeated..
A calculation, preferably done by a computer, checks the installed fixture data. The program then computes two lines that are perpendicular to the reference line and pass through the installed fixtures.
The surveyor mounts the rear fixture onto the wall by anchoring a suitable bracket to the wall, provided with an axially adjustable joint, and then connecting the grade rod to the joint. Before the mounting operation, he puts a prism at a chosen location for the back mounting bracket and shoots the prism. The prism is normally placed near to where the bracket will hold light fixture, and the obtained data (azimuth, horizontal distance, vertical distance and offset) is entered and recorded.
The surveyor uses the information obtained to decide if he wants to use this location for the fixtures. He then calls up the digital plan of the heading and inputs the x, y, z co-ordinates of the back bracket. The software program, which is based on spherical 1 S trigonometry, will calculate a theoretical elevation (z), perpendicular to the reference line, for the x, y of the light fixture bracket. The surveyor can measure up or down to the desired grade line, and then drill the holes in the wall and mount the back bracket.
The prism is then attached to the back mounting bracket with a typical prism mount and surveyed-in. The computer software will calculate the x, y, z of the back bracket and give the +/- error to the calculated perpendicular line, and the offset to the reference line.
The surveyor then chooses the location for the sight fixture, which should normally be not less than five meters from the rear bracket, and shoots the prism in like manner. The x, y, z of the prism are input into the computer software to calculate the +/- deviation to enable to move the prism to get the desired location. The surveyor measures to that point and mounts the light fixture bracket onto the wall in the same manner . However, the drilling accuracy will not be perfect every time, so the fixtures should enable fine vertical adjustment of t 2 cm. The prism is then attached to the front mounting bracket with a typical prism mount and surveyed-in.
Using the x, y, z of the two brackets, the software will calculate:
(a) the actual grade versus the theoretical grade;

(b) the effect of the grade error at a given distance, for example at 100 meters;
(c) the offset of the rear rod to the desired line (bearing);
(d) the offset of the front rod to the desired line (bearing).
When the actual grade is calculated by the program, the surveyor can make necessary adjustments to the front mount to set the grade at t 0.1 %. The program sets up two lines such that they start at the front or rear bracket, are perpendicular to the reference line and intersect the opposite wall. These points on the opposite wall of the drift are laid out and a small reflector (e.g. 2.5 cm in diameter) is mounted at each point. The reflectors are mounted level with the brackets on the opposite wall and create a line perpendicular to the reference line. The program computes the length of the grade rods necessary to establish the reference line.
The surveyor then installs the rods with their lengths set. The light beam is mounted at the outer extremity of the rear rod so as to constitute an extension of the rod, and the light beam dot is pointed at the reflection on the opposite wall, while the rod mounts are secured. The same process is repeated for the front rod. Once the two grade rods are so installed, the light beam is re-mounted on the rear rod aimed through the front sighting device provided at the outer end of the front rod, and the line is shot onto the face. A prism is then placed on the dot at the face and the data is recorded. The program computes the azimuth and grade from the end of the rods to the light beam dot on the face. The surveyor checks that any errors are acceptable or makes appropriate corrections. He marks the rod lengths on the wall and on the rods.
Using this check, there is no reason for a set of grade rods to cause mining errors. The wall brackets may have a protective dome bolted over them when not in use and the rods may be stored in a suitable pipe that is hung from the screen. At this stage, the surveyor's job is completed underground. In the office above ground, he can now download the recorded data directly to AutoCAD along with the rod lengths and issue prints. While underground, the surveyor did not require any heavy mining equipment or a helper, nor was the ventilation off. This, however, does not mean that the invention is limited to working without a helper, but rather that a helper is not absolutely required, as was the case previously.

Thus, the method of surveying a mine of tunnel in accordance with the present invention generally comprises:
(a) connecting two rods through a suitable attachment means to a wall of a mine or tunnel so that they extend a predetermined adjustable distance from said wall in an essentially parallel adjustable orientation to the grade with free extremities at the end and are so mounted at predetermined distance from each other, with one rod being a rear rod and the other being a front rod for the surveying purposes;
(b) adjusting said rods so that they become part of a reference line used for determining the line and grade of the mine or tunnel;
(c) providing a suitable concentrated beam at the free extremity of one rod and a suitable sighting device at the free extremity of the other rod;
(d) projecting a concentrated beam from one of the rods through the sighting device on the other rod so as to produce a reference, which is comprised of direction and grade, of heading that is being surveyed; and 1 S (e) recording the data obtained from shooting the reference line for subsequent analysis.
This novel survey system and method can also be effectively used in vertical mount applications, in raises or any other mining or tunnelling applications.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described with reference to the accompanying drawings, in which:
Fig. 1 is a perspective view of a mine heading with a prior art arrangement of a survey system;
Fig. 2 is a perspective view of a mine heading illustrating the survey system set up in accordance with the present invention;
Fig. 3 is a frontal view of a mine heading illustrating the survey set-up of the present invention; and Fig. 4 shows a rod installation on a mine wall, in accordance with this invention.

Fig. 5 illustrates a 3-axis joint that can be used for the purposes of rod installation pursuant to this invention.
DETAILED DESCRIPTION OF THE INVENTION
In the drawings, the same features are designated by the same reference S numbers.
Fig. 1 shows a prior art arrangement having a mine heading 10 at the back of which line plugs 12A and 12B are installed in the ceiling of the heading and grade plugs 14A and 14B are installed on both walls. Heavy equipment is normally required to perform the installation of the line plugs and hang lines 16A and 16B
therefrom and then two persons are needed to shoot the reference line 18 or the grade lines 20A
and 20B.
Fig. 2 illustrates the arrangement of the same mine heading 10 in accordance to the present invention. Here, brackets 22A and 22B are mounted on the wall of the mine or tunnel and rods 24A and 24B are extended therefrom. Grade lines 20A, are obtained as extension of rods 24A, 24B by shooting a prism to the other wall where reflectors 26A, 26B are mounted to create lines perpendicular to the reference line 18. This reference line 18 is obtained by projecting a concentrated beam located at the extremity of rod 24B, through a sighting device 28 located at the extremity of rod 24A and the spot 30 at the front of the mine heading 10 can then be marked by the same surveyor who set up the entire arrangement. The same procedure can be performed by a miner, unassisted.
Another view of the set-up of the present invention is shown in Fig. 3 where it is clearly illustrated how brackets 22A and 22B are mounted to the wall of the mine heading 10.
Rods 24A, 24B extend laterally from the brackets 22A, 22B, parallel to the ground 11 of the tunnel, drift or ramp. These rods are positioned at approximately five meters from one another. The rods are extensible to a length of about three meters, although in some cases this may be longer when corners are being surveyed;
in such cases a vertical stabilizing support may need to be provided at the free end of the rod. These rods 24A, 24B are normally obtained in 1 meter extensions with a removable level bubble mounted on the top and an adjustable section made similar to a range pole, so that the surveyor may set the appropriate length as required.
The rods are also available in 5' ( 150 cm) lengths that are subsequently cut by the surveyor to the calculated lengths. Once the rods 24A, 24B are properly installed and positioned with respect to reflectors 26A, 26B, the reference line is established.
Then, the light beam transmitter 21 is mounted at the end the rear rod 22B and a sighting device 28, such as a washer, is mounted at the end of the front rod 22A.
The light beam transmitter 21 should normally produce a beam that is <0.1 m at m distance and have a range of at least 200 m. The light beam passes through the sighting device 28 to establish the reference line 18 and the light beam spot 30 on the face of the mine tunnel 10 can thus be marked.
Fig. 4 provides a more detailed view of a preferred embodiment of rod installation. As shown in this figure bracket 22, which in this case is an equilateral triangular steel plate, has holes 23 at its apexes through which anchors may be inserted so as to solidly fix the bracket to the mine wall. The bracket 22 has a three-axis joint 25 connected thereto so that the rod 24 may be adjusted in its x, y, z axial positions. Rod 24 is provided with extension means 27 so that its length may be adjusted as desired. The rods are also available in standard lengths that are subsequently cut by the surveyor to the calculated lengths. At one of its ends, rod 24 is provided with an attachment fixture 29 that enables it to be removably attached to the joint 25. A prism attachment 32 may also be connected to the joint 25. At the other end of rod 24 there is provided a connecting sleeve 31 through which a light beam transmitter 21 or a sighting device 28 can be connected to the rod; this arrangement can thus be used either for the front rod 24A or for the back rod 24B as required.
Finally, in Fig. 5 there is provided an illustration of a preferred embodiment of the 3-axis joint 25 which, in this case, is mounted within triangular bracket elements 22A, 22B with holes 23A, 23B at the apexes being used for the attachment to the mine wall. The circular body 34 has a cylindrical protrusion 36 to which the rod 24 may be connected. This body 34 is movable within the triangular bracket elements 22A, 22B so as to be adjustable in three-axial directions, thereby permitting adjustment of the rod in the x, y, z directions.
It should, of course, be understood that the invention is not limited to the specific embodiment described above but that various modifications obvious to those skilled in the art can be made therein without departing from the spirit of the invention and the scope of the following claims.

Claims

1. A mining or tunnelling survey system which comprises:
(a) two rods connected through suitable attachment means to a wall of a mine or tunnel and extending a predetermined distance from said wall in an essentially parallel orientation to the ground, said rods having free distal extremities and being mounted at a predetermined distance from one another with one rod being a rear rod and the other being a front rod for the purposes of the survey;
(b) means for adjusting said rods so that they become part of line and grade layout of the mine or tunnel;
(c) a light beam transmitter provided at the distal extremity of the rear rod and a suitable sighting device provided at the distal extremity of the front rod and arranged so that the beam from the light beam transmitter projects through the sighting device and produces a reference line, comprised of direction and grade, ending on the face of the mine or tunnel that is being surveyed; and (d) means for laying out and recording data obtained from shooting the line and grade of the reference line, for subsequent analysis.

2. A mining or tunnelling survey system according to claim 1, in which the attachment means by which the rods are connected to the wall comprise a three-axis joint which allows axial adjustments of the rods in x, y, z directions.

3. A mining or tunnelling survey system according to claims 1 or 2, in which the rods are extensible to a predetermined distance from the wall.

4. A mining or tunnelling survey system according to claims 1, 2 or 3 in which in the area where the rods are attached to the wall, means are provided for insertion of a prism suitable for adjusting the position of the rods so as to make the rods pan of the reference line.

5. A mining or tunnelling survey system according to claim 4, in which small reflectors are provided on the wall opposite to the wall where the rods are mounted, said reflectors being level with the prism used to establish the grade lines.

6. A mining or tunnelling survey system, according to any one of the preceding claims 1 to 5, in which the means for adjusting the rods so that they become part of the reference line software using spherical trigonometry and capable of calculating (a) the actual grade versus the theoretical grade; (b) the effect of the grade error at a predetermined distance; (c) the offset of the rear rod to the desired line;
and (d) the offset of the front rod to the desired line.

7. A mining or tunnelling survey system according to any one of preceding claims 1 to 6, in which the light beam transmitter is a laser diode capable of producing a beam that is <0.1 M at 200 m distance and has a range of at least 200 m.

8. A mining or tunnelling survey system according to any one of the claims 1 to 7, in which the sighting device is a washer attached to the distal extremity of the front rod.

9. A mining or tunnelling survey system according to any one of claims 1 to 8, in which the means for laying out and recording data obtained from shooting the line and grade of the reference line include suitable surveying prisms and a recording calculator, total station instrument or computer.

10. A method of surveying a mine or a tunnel which comprises:
(a) connecting two rods through suitable attachment means to a wall of a mine or tunnel so that they extend a predetermined adjustable distance from said wall in an essentially parallel adjustable orientation to the ground with distal extremities and are so mounted at a predetermined distance from each other, with one rod being a rear rod and the other being a front rod for the surveying purposes;
(b) adjusting said rods so that they become part of line and grade layout of the mine or tunnel;
(c) providing a suitable light beam transmitter at the distal extremity of the rear rod and a suitable sighting device at the distal extremity of the front rod;
(d) projecting a light beam from the transmitter on the rear rod through the sighting device on the front rod so as to produce a reference line perpendicular to the grade layout and ending with a dot on the face of the mine or tunnel that is being surveyed; and (e) laying out and recording the data obtained from shooting the line and grade of the reference line for subsequent analysis.

11. A method according to claim 1, in which the rod, which constitutes Station 1, is mounted first and its length is adjusted using a software program based on spherical trigonometry.

12. A method according to claim 11, in which the rod which constitutes Station 2, is mounted after the rod of Station 1, in like manner, and its length and vertical position are adjusted in a similar manner.

13. A method according to claims 11 or 12, in which prior to mounting the rear or front rod, a prism is placed where the rod is to be mounted and shooting of the prism is performed to obtain data of azimuth, horizontal distance, vertical distance and offset for the rear grade line, which data is entered into a calculator, total station instrument or computer using suitable software, which allows to determine whether the location for mounting the rod is satisfactory.

14. A method according to claim 13, in which the calculator, total station instrument or computer uses a software program based on spherical trigonometry capable of calculating:
(a) actual grade versus theoretical grade;
(b) the effect of grade error at a predetermined distance; and (c) the offset of the rear and front rods to the desired line.

15. A method according to claim 14, in which the software program sets-up two lines starting where the rear and front rods are to be mounted to the wall and ending on the opposite wall, and a small reflector is then installed at each location on the opposite wall where these lines end, thereby creating two lines perpendicular to the reference line and said software program computes the length of the rods necessary to establish the reference line, on grade.

16. A method according to claim 15, in which the adjustment of the rods includes providing a light beam transmitter at the free extremity of each rod and pointing it at the reflector on the opposite wall, thereby determining the grade lines.

17. A method according to any one of claims 10 to 16, in which the ligth beam transmitter provided at the free extremity of the rear rod is a laser diode capable of producing a light beam that is <0.1 m at 200 m distance and has a range of at least 200 m.

18. A method according to claim 17 in which the light beam is shot through the sighting device on the front rod to produce a reference line ending with a dot on the face of the mine or tunnel, which is then marked by the surveyor.

19. A method according to claim 18, in which a prism is placed on the dot at the face and the data obtained is layed out and recorded on the calculator, total station instrument or computer with the software that computes the azimuth and grade from the end of the rods to the laser dot on the face and allows to check any inexactitudes and to make appropriate corrections.

20. A method according to any one of preceding claims 13 to 19, in which the software uses spherical trigonometry to determine two planes, one being the grade component and the other being the direction, azimuth or bearing component, the intersection of these two planes describing the vector which represents the reference line being used for the survey, the vector being physically represented by the light beam.

21. A method according to any one of preceding claims 10 to 20, which is performed by one surveyor.