Laser positioner and marking method using the same

Abstract: A laser positioner is located at a survey basic point (Po) for projecting a geodetic design pattern depicting design working points onto a working face (Fc) remote from the basic point (Po) by use of a laser pattern projector (13), upon surveying an objective route by a laser surveying unit (11). In tunnelling works, for example, while forming the design pattern on the working face (Fc), work of boring holes for charging explosives in the working face can be performed without paint-marking on the working face.

Description: This invention relates to a laser positioner for automatically measuring geodetically specified points and optically forming geodetic pattern on a working face in construction works, tunnelling works or the like by use of surveying laser instruments, and a method for optically marking boring points on a working face of a tunnel in tunnelling work by use of the laser positioner. It is prerequisite to make an elaborate survey and precisely mark on a working face in order to determine the surveying reference points necessary for carrying out various construction works such as road and tunnelling works. Though these surveying works were onerous and troublesome in the past, accuracy of surveying for road, tunnelling, building constructions and so on has been significantly improved and the operational efficiency of survey has been far advanced by use of laser surveying instruments. The laser instruments using a visible ray has been advantageously applied to the tunnelling work which is carried out in a dark place. As one example, the work of marking points at which explosive charging holes are bored in a working face of the tunnel cannot be automated even now and has been so far carried out manually. In the tunnelling work (e.g. New Austrian Tunnelling Method: NATM; patented to L.V. Rabcewicz), the hard base rock of the working face is often blasted with explosives. Therefore, the holes for charging the explosives are previously bored in the working face at the geodetically specified points predetermined in accordance with designs of construction which are strictly made in advance. Although the specified points at which explosive charging holes are bored in the working face of the tunnel can be designed automatically with ease by use of a computer, the work of marking at the design points for boring the explosive charging holes has however been manually carried out, and automation of marking on the working face in the tunnelling construction cannot yet be accomplished. It would be possible to utilize a computer and a laser system in marking the points on the working face of the tunnel. That is, the boring points at which explosive charging holes are bored in the working face can be predetermined by use of the computer. Then, while directing a laser spot corresponding to one of the predetermined boring points onto the working face by use of a laser oscillator under the control of the computer, the position at which the laser spot representing the predetermined boring point is formed on the working face of the tunnel is manually marked with paint. The manual marking work with paint is successively continued for other boring points in order, but turns out to be a very troublesome chore. WO 80/01003 describes a laser positioner and a method in accordance with the preambles of claims 1 and 7 respectively. This invention was made in consideration of the aforenoted drawbacks of the conventional laser marking method. Its object is to provide a laser positioner capable of automatically effecting measurement of surveying points, arithmetic processing for determining design points, and optical formation of a visible pattern corresponding to the design points on an objective face. Another object of this invention is to provide a marking method using the aforesaid laser positioner, by which specific points designed on the basis of the measured surveying points can be concurrently formed automatically in the form of a visible pattern on the objective face by use of a laser pattern projector, so that the designed specific points can be optically marked effectively. Still another object of this invention is to provide a laser positioner capable of measuring the surveying points and forming the designed specific points in the form of a visible pattern on the objective face such as a working face of a tunnel, which can be remote controlled to improve workability of marking. The invention provides a laser positioner in accordance with Claim 1. The laser surveying unit has a laser oscillator for directing a laser spot toward reference targets so that distances and angles of the laser surveying unit relative to the respective reference targets can be measured by receiving reflected rays from the reference targets. The laser surveying unit and laser pattern projector may be united and controlled through wireless control means remote from the surveying basic point at which the laser surveying unit and laser pattern projector are positioned. The invention also provides a marking method in accordance with Claim 7. In a case that the objective face is the working face of a tunnel, the points to be bored for charging explosives can be depicted by projecting the design specific points in the form of a laser pattern on the working face. Thus, while projecting the design specific points on the working face, explosive charging holes can be directly bored on the working face without paint-marking. The other objects and features of the present invention will be hereinafter explained in detail with reference to the accompanying drawings, wherein FIG. 1 is a schematic diagram showing one embodiment of the laser positioner according to this invention, which is applied to tunnelling works; FIGS. 2(A) and 2(B) are explanatory diagrams showing the operating principle of the laser positioner of this invention; and FIG. 3 is a flow chart for optically marking on an objective face by use of the laser positioner of this invention. A laser positioner 1 of this invention which is applied to construction work for excavating a tunnel is illustrated in FIG. 1. The laser positioner 1 includes an operation system 10 which is located at a basic point Po remote from an objective face Fc to be marked, and a control system 20 for controlling the operation system 10. In this case, the objective face Fc is a working or pit face of the tunnel. The operation system 10 comprises a laser surveying unit 11 such as a so-called "laser theodolite" or "total station" which directs a laser beam bl toward a reflector target and receives a reflected beam b2 from the target so as to measure the distance and angle of the target relative to the basic point Po, a laser beam generator 12 capable of issuing a laser beam b3 in parallel to the laser beam b1 issued from the laser surveying unit 11, and a laser pattern projector 13 including a high output laser oscillator 13a and laser deflecting means 13b. In this embodiment, the aforenoted laser surveying unit 11 and laser pattern projector 13 are together retained within a portable casing 14, but may be separated from each other if the relative position of the laser surveying unit 11 and the laser pattern projector 13 can be realized. The laser surveying unit 11 may be constituted by combining a laser range finder and a goniometer. The laser beam generator 12 for issuing a laser beam to form a single laser spot on the objective face is secured integrally with the laser surveying unit 11, but is not absolutely necessary to this invention. As the laser pattern projector 13, there may be used a common laser image display system capable of forming an image pattern by projecting and deflecting a laser beam outputted from a laser oscillator. The united laser surveying unit 11 and laser beam generator 12 are retained on a universal slewing means composed of a horizontally rotating motor 15a and vertically rotating motor 15b so that the laser beams b1 and b3 issued from them can be directed substantially in all directions. The control system 20 includes a control console 21 for controlling the operations of the laser surveying unit 11, the laser pattern projector 13 and other driving elements in accordance with command signals and predetermined control parameters, and an arithmetic control unit 22 to which the command signals and control parameters are given manually. The arithmetic control unit 22 is connected to the laser surveying unit 11, laser beam generator 12 and laser pattern projector 13 through the control console 21 so as to process surveying data fed from the laser surveying unit 11 and output automatic control signals to the laser surveying unit 11, laser beam generator 12 and laser pattern projector 13. The arithmetic control unit 22 has, for example, a data input means such as a keyboard 23, a display means 24 such as a CRT, a memory unit 25 for storing various data. As the control unit 22, there may be used a general purpose computer, preferably, a handheld computer. Of course, a printer 26 may be utilized. The control system 20 further has a wireless control system composed of a wireless transmitter hand unit 27 for transmitting control command signals, and a wireless receiver unit 28 connected to the control console 21. With this wireless control system, the laser surveying unit 11, laser beam generator 12 and laser pattern projector 13 can be controlled from a remote place. Next, the method for marking points for boring explosive charging holes in the working face of a tunnel under construction by use of the laser positioner according to this invention will be explained with reference to generalized diagrams shown in FIGS. 2(A) and 2(B) and a flow chart of FIG. 3. It is a matter of course that this invention is here applied for the marking of points for boring holes in the tunnelling work as one embodiment of this invention, but applicable to any other construction and industrial fields. Prior to execution of the tunnelling work, a geological survey and a soil analysis are performed for preparing planning and executing designs so as to determine the number and points (coordinates: Xhm, Yhm, Zhm) [m=1...n] of explosive charging holes to be bored in the working face Fc at every location along the design route of the desired tunnel. (Process I) The coordinates of the designed points for the explosive charging holes can be determined by the angles of the directions of X-axis, Y-axis and Z-axis. The designed points are expressed by mathematics which is programmed in the arithmetic control unit 22. When boring the explosive charging holes in the working face, the designed points for the boring holes are required to be marked on the working face Fc. First of the operations for marking the boring points thus designed, the aforenoted laser positioner 1 of this invention is located confronting the working face (marking surface) Fc at the basic point Po remote from the working face Fc. (Process II) The basic point Po may be determined at any place in the tunnel, but it is defined by predetermined positional coordinates (Xo, Yo, Zo) realized previously by the aforesaid designing process. Also, the laser positioner 1 may be located anywhere in the cross section at the basic point Po, but it is preferably fixed on the crown portion of the tunnel by use of suspending means (not shown) to keep out of the way in the tunnel. The control system 20 including the control console 21 and arithmetic control unit 22 is placed near the laser positioner 1, and the wireless receiver unit 28 is connected to the control console 21. In general, it is desirable to locate the laser positioner 1 about 50 meters away from the working face Fc, when the route in the tunnel is straight. Next, at three reference points in a cross section (reference section surface) Fr which is arbitrarily determined in the tunnel, reflector targets T1, T2, T3 are located. (Process III) The absolute coordinates (Xrk, Yrk, Zrk) [k=1, 2, 3] of the reference points at which the targets are located may be determined in advance in designing the tunnel, or can be found in executing the work by use of the laser surveying unit 11. The reference centre Pr of the reference section surface Fr is usually positioned at about 40 meter's distance from the basic point Po, when the route of the tunnel is straight. As the targets T1-T3, there may be used a cubic corner prism capable of reflecting incident light to the direction in parallel to the incident light. Then, the laser survey unit 11 is operated to direct the laser beam bl to the respective reflector targets T1-T3 so as to precisely measure the distances from the unit 11 to the respective targets T1-T3 on the basis of the time difference between the laser beam b1 outputted therefrom and the reflected laser beam b2 returning from the targets T1-T3, and at the same time, find the angles at which the laser beam bl is directed to the respective targets. From the survey data which are obtained from the measured distances and angles (X-axis deflection angle x and Y-axis deflection angle y) relative to the respective targets, the relative position (absolute coordinates: Xo, Yo, Zo) of the laser positioner 1 to the targets can be perceived with a high degree of accuracy. Further, the distance from the basic point Po to the working face (marking face) Fc is measured by directing the laser beam bl from the laser survey unit 11 to a reflector prism which is disposed onto the working face Fc for light wave measurement. Thus, the absolute coordinates of the working face Fc is obtained. (Process IV) Upon measurement of the absolute positional coordinates of the laser positioner 1 and the working face Fc, the positional data (coordinates: Xhm, Yhm, Zhm [m=1...n]) predetermined in Process I noted above for determining the points at which the desired explosive charging holes are bored in the working face Fc are inputted to the arithmetic control unit 22 to perform mathematical computations and obtain control signals Sh, Sv for operating the laser pattern projector 13. (Process V) With the control signals Sh, Sv from the control unit 22, the laser beam generator 12 may be operated to issue the laser beam b3 toward the working face Fc so as to form a single laser spot by which the points to be bored for explosive charging holes are optically indicated one by one. In this case, an operator nearby the working face Fc can remotely control the laser beam generator 12 by means of the wireless control system including the transmitter hand unit 27. By inputting the control signals Sh, Sv to the laser deflection means 13b of the laser pattern projector 13, the laser beam issued from the laser oscillator 13a can be horizontally and vertically deflected continuously to form a laser pattern indicating concurrently all the explosive charging holes h1..hm..hn on the working face Fc as illustrated in FIG. 2(B). (Process VI) While projecting the laser pattern to optically mark the desired points on the working face, boring work is carried out to form the holes for charging the explosives in the working face without paint-marking, for example. Upon completion of boring of explosive charging holes in the working face, charging of explosives into the bored holes, blasting, mucking, and timbering are effected in order to drive forward the working face. (Process VII) Thus, one cycle of the working processes of tunnelling is finished and repeated from the aforenoted Process IV in which the surveying for measuring the absolute position of the working face newly built. If the working face newly built is much too distant from the basic point Po, or cannot be viewed from the basic point Po in a curved route, the laser positioner 1 is moved toward the working face. In this case, the marking work is started from Process II described above. The command data inputted to the arithmetic control unit 22 and the measured data obtained as the result of surveying in respect to the basic and reference points, the positional data of the working face and other necessary data can be concurrently displayed on the display means 24, outputted to the printer 26, and stored in the memory unit 25. Every work of controlling the laser positioner 1 can be performed by the operator near the working face by using the transmitter hand unit 27. In a tunnelling explosion method such as the NATM method in which cut-holes are possibly formed in the working face, it is preferable to differentiate the cut-holes from the explosive charging holes by different marks of the laser pattern formed on the working face. Thus, a mistake of charging the explosives can be prevented. As is clear from the above, this invention provides the laser positioner capable of automatically effecting measurement of surveying points, arithmetic processing for determining design points, and optical formation of a visible pattern depicting the design points on an objective face. Besides, by using the laser positioner, geodetically specified points can be marked in the form of a visible pattern on the working face of a tunnel so as to facilitate boring works. Furthermore, the measurement of surveying points and projection of the desired pattern on the working face can be remote controlled by use of the wireless control system to improve workability of marking.

Claims: A laser positioner comprising an operation system (10) including a laser surveying unit (11) for issuing a laser beam (bl) toward at least one reflector target disposed on or around an objective face (Fc) and receiving a reflected beam (b2) from said reflector target to effect distance and angular measurements relative to the target to obtain surveying data representing the absolute coordinates of the objective face (Fc), a control system (20) including an arithmetic control unit (22) for determining design points (h1..hm..hn) to be formed on said objective face (Fc) on the basis of said surveying data given from said laser surveying unit (11), setting control command signals and controlling the laser surveying unit (11) during measurement, and a laser pattern projector (13) for issuing a single laser beam toward said objective face (Fc) to form said design points on the objective face on the basis of said surveying data, characterized in that said laser pattern projector (13) comprises horizontally and vertically deflecting means (136) which are controlled by said controlling system (20) to continuously deflect horizontally and vertically the laser beam so as to horizontally and vertically sweep said objective face with said laser beam to form a pattern including laser spots representing said design points on said objective face for optically marking said objective face by the laser spots. A laser positioner according to Claim 1 wherein said operation system (10) further includes a laser beam generator (12) for issuing a laser beam (b3) to form a single laser spot on the objective face in accordance with said design points. A laser positioner according to Claim 1 or Claim 2, wherein said operation system (10) is retained on a universal slewing means composed of a horizontally rotating motor (15a) and vertically rotating motor (15b) so as to direct the laser beam (b1) issued from said laser surveying unit (11) substantially in all directions. A laser positioner according to any one of Claims 1 - 3, wherein said operation system (10) is retained within a portable casing (14). A laser positioner according to any preceding claim wherein said control system (20) includes a control console (21) for controlling said laser surveying unit (11) and said laser pattern projector (13) in accordance with command signals and design data set in said arithmetic control unit (22), said arithmetic control unit (22) having a keyboard (23) for inputting command signals and design data, a display means (24), and a memory unit (25) for storing design data. A laser positioner according to any preceding claim wherein said control system (20) includes a wireless control system composed of a wireless transmitter hand unit (27) for transmitting control command signals and a wireless receiver unit (28) connected to said control system (20). A method for marking design points on an objective face by use of a laser positioner (1) comprising a laser surveying unit (11) for effecting distance and angular measurements to obtain surveying data representing the absolute coordinates of the objective face (Fc), a control system (20) for determining the design points based on the results of the distance and angular measurement and controlling the laser surveying unit (11), and a laser pattern projector (13) for forming a pattern representing the design points on the objective face to be marked on the basis of said surveying data, which comprises measuring surveying reference points and said objective face on the basis of the reference points by use of said laser surveying unit (11) to obtain coordinates of the reference points and the absolute position of the objective face, characterized by projecting a single laser beam from the laser pattern projector (13) comprising horizontally and vertically deflecting means (13b) which are controlled by said control system (20) to continuously deflect horizontally and vertically said laser beam so as to horizontally and vertically sweep said objective face with said laser beam to form a pattern including the laser spots representing said design points on said objective face for optically marking said objective face by the laser spots. A method as claimed in Claim 7 for marking design points on a working face (Fc) in a tunnel, comprising: performing a geological survey and a soil analysis for preparing, planning and executing designs so as to determine design data representing the number and points of explosive charging holes to be bored in the working face (Fc) at every location along a design route of the desired tunnel, locating said laser positioner (1) at a basic point (Po), locating reflector targets at reference points, operating said laser surveying unit (11) to direct a laser beam to the reflector targets so as to measure the distances and angles of the laser surveying unit (11) relative to the respective targets to obtain absolute coordinates of the working face (Fc), inputting to said control system (20) said design data for determining points at which the desired explosive charging holes are bored in the working face (Fc) and obtaining control signals for operating the laser pattern projector (13), inputting the control signals to the laser pattern projector (13) to form a laser pattern indicating concurrently all the explosive charging holes on the working face (Fc), and carrying out boring work while projecting the laser pattern to optically mark the desired points on the working face (Fc) to form the holes for charging the explosives in the working face.

Inventors: FUKUNAGA NOBUYUKI, ISHIDA YOSHIAKI, KIMURA MUTSUHIKO, METOKI YASUO, MIYAHARA KENJI, SAITO TAKEO, FUKUNAGA, NOBUYUKI, ISHIDA, YOSHIAKI, KIMURA, MUTSUHIKO, METOKI, YASUO, MIYAHARA, KENJI, SAITO, TAKEO
Applicants: MAC CO LTD, SATO KOGYO, MAC CO.,LTD., SATO KOGYO CO., LTD.
Application year: 1991
Main classification: G01C15
IPC codes: G01C15, G01C7