Abstract:
A laser projection apparatus and method for identifying specified coordinates on varied surfaces. A controller directs two or more laser projectors to intersect laser lines at a specified location. The locations of the modules are identified by calculating a rotational angle and two or more known coordinates. Once the location of the modules is calculated, angle to angle intersection is used to identify additional locations. The user indicates with the controller which location is to be identified. The controller processes the calculations and commands the laser projectors to draw the intersecting laser lines at the specified location. The intersecting laser lines are actuated in a strobe effect to attract the user&#39;s attention to the position. This apparatus and method allows users to quickly and easily locate specified locations without needing to take individual measurements for the purposes of alignment, construction, verification and the like.

Description:
BACKGROUND OF INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The present invention generally relates to a method and device for identifying specified coordinates using two or more visible lasers. In more detail, the present invention relates to using two or more visible lasers lines and a method for calculating an angle to angle intersection to obtain the coordinates of predetermined locations. 
         [0003]    The art of large scale measurement and surveying involves the determination of unknown positions, or setting out of known coordinates using angle and distance measurements taken from one or more positions. In order to make these measurements, a surveying device or instrument frequently used is the type which is often called a total station. A total station is an electronic theodolite integrated with an electronic distance meter to read slope distances from the instrument to a particular point. The total station distance measuring instrument is capable of processing integrated distance and angular measurement calculations. A total station is furthermore provided with a computer control unit that records measurements and stores data obtained during the measurement process. This computer control unit is often referred to as a data collector. Preferably, the total station calculates the position of a target in a fixed ground-based coordinate system. Although total stations are well known, they have various disadvantages when used in small scale engineering surveys. The survey information although high quality in terms of accuracy, is time consuming and expensive to conduct, and normally requires at least two people. 
         [0004]    Additional inexpensive and well known manual methods of measurement are often used to identify locations used in construction. These methods generally involve identifying a starting point or location and measuring the distance to additional points. Further measurements must be taken to ensure that the lines are perpendicular and that corners are thus 90 degree angles. A tape measure or appropriate device is used to measure the hypotenuse of a right triangle defined by the previously identified points. If a 90 degree angle is not achieved, then the previously identified points must be moved and the distance measured again. The workers move the points and measure the distance again and again until the right distance and angles are found and result in defining the correct layout. This process often takes a considerable amount of time and requires two or more workers to perform the process. Further, because the workers&#39; best guess or estimation is utilized in positioning the points, the possibility for error is greatly increased. 
         [0005]    2. Prior Art 
         [0006]    The following is a tabulation of some prior art that presently appears relevant: 
       U.S. Patents 
       [0007]      
         [0000]    
       
         
               
               
               
               
             
           
               
                   
               
               
                 Pat. No. 
                 Kind Code 
                 Issue Date 
                 Patentee 
               
               
                   
               
             
             
               
                 3,865,491 
                 C1 
                 Feb. 11 th , 1975 
                 William M. Hogan 
               
               
                 3,471,234 
                 C1 
                 Oct. 7 th , 1969 
                 Robert H. Studebaker 
               
               
                 4,820,041 
                 C1 
                 Apr. 11 th , 1989 
                 Richard W. Davidson 
               
               
                 4,912,643 
                 C1 
                 Mar. 27, 1990 
                 Terence P. Beirxe 
               
               
                 4,688,933 
                 C1 
                 Aug. 25 th , 1987 
                 James M. Lapeyre 
               
               
                 7,181,853 
                 C1 
                 Feb. 27, 2007 
                 Charles E. Heger 
               
               
                 7,287,336 
                 C1 
                 Oct. 30, 2007 
                 Gary Goodrich 
               
               
                   
               
             
          
         
       
     
         [0008]    For large scale measurement and surveying it is often necessary to accurately position an optical instrument such as a telescope, a camera, a range finder, a laser or the like. Generally, human intervention is required to align such optical instruments with a desired target. Human operation of optical instruments is not only expensive, but is sometimes subject to inaccuracies and errors, especially in cases where humans are required to estimate the location over and over until the desired target is identified. 
         [0009]    Specifically in surveying operations it is often required to direct a laser beam upon a surveying stadia rod, prism or similar target. In some systems an operator is required at the laser support to continuously position the laser beam so as to impinge upon the stadia rod or prism. In other systems, the laser beam is continuously rotated about a horizontal plane in order to periodically impinge upon a stadia rod, prism or another measuring target. Current Surveying systems often have complicated operating procedures and require expensive equipment Examples of such laser surveying systems are found in U.S. Pat. No. 3,865,491 issued Feb. 11, 1975, and U.S. Pat. No. 3,471,234 issued Oct. 7, 1969. 
         [0010]    Surveying and measuring systems that utilize the observation of angles for identifying an unknown position or target are used with both large scale and small scale measurement and position identification. These position identification systems will often utilize 2 or more base stations to project a visible or non-visible light source, and take measurements based on the location of said base stations. These positions identification systems often require a stadia rod, prism or other measuring target in order to detect and calculate the desired coordinates and locations. Systems of this nature are not as widely utilized in land surveying and construction and often require expensive equipment and additional training. Examples of such laser position detection systems are found in U.S. Pat. No. 4,820,041 issued on Apr. 11, 1989, U.S. Pat. No. 4,912,643 issued on Mar. 27, 1990, and U.S. Pat. No. 4,688,933 issued on Aug. 25, 1987. 
         [0011]    Laser dot and laser line projection systems are often used in construction to generate parallel planes, identify straight lines or point to specified locations. When utilizing visible laser projection systems, it is often necessary to manually measure the position of the lasers in order to identify the desired location. Measurement errors may be produced in the event the user did not calculate the position of the laser correctly. Examples of such laser projection systems are found in U.S. Pat. No. 7,181,853 issued on Feb. 27, 2007, and U.S. Pat. No. 7,287,336 issued on Oct. 30, 2007. 
       SUMMARY OF INVENTION 
       [0012]    One or more implementations of the invention is to provide a laser projection system and method that allows users to quickly and easily locate specified locations without needing to take individual measurements for the purposes of alignment, construction layout, location verification and the like. 
         [0013]    The advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
         [0014]    Accordingly, one or more embodiments provide a method and apparatus for calculating and identifying specified locations that does not require a stadia rod or prism, that requires only one person to operate, that utilize visible lasers that are actuated to draw a line for better visibility, that utilizes two or more laser lines that intersect at specified locations for simplified position identification, that can accurately locate or measure X and Y distance even when there is a difference in elevation, that reduces measurement error, that requires minimal training, and that is relatively inexpensive. Other advantages of one or more aspects will be apparent from consideration of the drawings and ensuing description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  shows an embodiment of the laser projection apparatus according to the present invention. 
           [0016]      FIG. 2  is a simplified perspective view of the laser projector 
           [0017]      FIG. 3  is an exploded view of the laser projector 
           [0018]      FIG. 4  shows a flowchart of the operation of the system according to the invention 
           [0019]      FIG. 5  illustrates the measuring method used 
       
    
    
     LIST OF DRAWINGS REFERENCE NUMBERS 
       [0000]    
       
           110  First Laser Projector 
           120  Second Laser Projector 
           130  First Tripod 
           140  Second Tripod 
           150  First Laser Beam 
           160  Second Laser Beam 
           170  first Laser Line 
           180  Second Laser Line 
           190  Specified Location 
           195  Data Collector 
           210  Laser Window 
           220  Top Cover 
           230  Rotation Assembly 
           240  Base Housing 
           250  On/Off Switch 
           310  Single Board Computer 
           320  Motor 
           330  Galvanometer 
           340  Laser 
           350  Laser Mount 
           360  Light Detector 
           370  Encoder 
           381  First Pulley 
           382  Second Pulley 
           390  Drive Belt 
           410  Power On 
           420  Connect Confirmation 
           430  Receive Command 
           440  Process Command 
           445  Control Program 
           450  Update Galvo 
           460  Update Motor 
           470  Read Encoder 
           480  Read Light Detector 
           490  Transmit Status 
       
     
       DETAILED DESCRIPTION OF THE INVENTION 
       [0055]    One embodiment of the present invention will now be explained in detail with reference to the drawings. It should be understood, however, that this embodiment is an example. The range of technical applications of the present invention should not be limited to the preferred embodiment. 
         [0056]      FIG. 1  is a pictorial view of one embodiment of the present invention illustrating the relative alignment of the individual First and Second Laser Projectors  110  and  120  according to one embodiment of the present invention, which are of significance to identify specified locations for surveying or construction. First and Second Laser Projectors  110  and  120  are placed on First and Second Tripods  130  and  140 . First Laser Projector  110  projects First Laser Beam  150 . Second Laser Projector  120  projects Second Laser Beam  160 . First Laser Beam  150  is used to draw First Laser Line  170  and Second Laser Beam  160  is used to draw Second Laser Line  180 . The intersecting location of First and Second Laser Lines  170  and  180  designates the Specified Location  190 . Data Collector  195  may be employed as a wireless engineering survey data collection system configured for survey data capture, wireless connectivity via multiple alternative formats/protocols, and high precision survey grade angle and distance measurement calculation. The illustrated embodiment is thus configured for use with a Data Collector capable of in-field coordinate geometry. Data Collector  195  interfaces with the wireless digital communications included in Single Board Computer  310  ( FIG. 3 ) of Laser Projectors  110  and  120 . 
         [0057]      FIG. 2  shows one embodiment of the present invention. In this embodiment, Laser projectors  110  and  120  similarly comprise a Base Housing  240 , a Rotation Assembly  230  and Top Cover  220 . The upper portion of Laser Projectors  110  and  120  are able to rotate about the vertical axis. Rotation Assembly  230  and Top Cover  220  are connected and rotate 180 degrees over the stationary Base Housing  240 . Top Cover  210  has a Laser Window through which a laser beam is projected. 
         [0058]    Referring to  FIG. 3  the Rotation Assembly  230  and Top Cover  220  are capable of rotating 180 degrees over Base Housing  240  using a drive system comprised of a Motor  320 , Encoder  370 , First Pulley  381 , Second Pulley  382 , and Drive Belt  390 . The laser  340  and Galvanometer  330  are supported by Laser Mount  350 . A laser beam is produced by and projected from the Laser  340 . The laser beam is reflected and accurately actuated by the Galvanometer  330 . Light Detector  360  is mounted in an internal location that is visible from the outside through Laser Window  210 . Light Detector  360  detects a laser beam when projected from the alternate First and Second Laser Projectors  110  or  120 . Light Detector  360  is used for set-up and calibration. A Single Board Computer  310  includes one or more processors and system memory and is used to control the Motor  320 , Encoder  370 , Light Detector  360  and Galvanometer  330 . On/Off Switch  250  controls the main power to First and Second Laser Projectors  110  and  120   
         [0059]      FIG. 4  in accordance with the present invention illustrates the flow of operation, sometimes referred to as a functional block diagram. The first step in the operation is carried out by Power On  410 . Power On  410  initiates a Control Program that is stored in the ROM contained in Single Board Computer  310  and associated with First and Second Laser Projectors  110  and  120 , which controls the detection and selection of each command and adjustment of operating parameter(s) for the respective instructions. 
         [0060]    When First and Second Laser Projectors  110  and  120  are turned on, the Connect Confirmation  420  instruction is initiated to ensure a wireless connection is established between Data Collector  195  and the Single Board Computer  310  on both First and Second Laser Projectors  110  and  120 . When an instruction is received from Command Received  430 , Process Command  440  begins to collect data and provide instruction with Control Program  445 . Control Program  445  and the calculations included herein are explained in reference to  FIG. 5  and further explained in the entire Detailed Description of the Invention. When the user inputs an operating parameter or instruction into the Data Collector  195 , the Command Received  430  initiates the Process Command  440 . When Process Command  440  is received, Control Program  445  calculates the parameters and provides instructions to Update Galvo  450 , Update Motor  460 , Read Encoder  470 , and Light Detector  480 . Transmit Status  490  then sends information to Data Collector  195  via wireless connection. The entire process is repeated until the parameters and instructions calculated by Control Program  445  are complete and the corresponding data is stored and recorded. 
         [0061]    The systems and methods embodying the present invention can be programmed in any suitable language and technology, such as, but not limited to: C, C++; Visual Basic; Java; VBScript; Jscript DHTM1; XML and CGI. Alternate versions may be developed using other programming languages. 
         [0062]    The two-way wireless data communication may utilize, but is not limited to, Radio Communication or Wi-Fi (Wireless Fidelity). First Laser Projector  110  and Second Laser Projector  120  each include two way wireless data communication. 
       Operation—FIGS. 1,  3 ,  4 ,  5   
       [0063]    In use, a Laser  340  directs a laser beam toward a Galvanometer  330 . A Galvanometer is an analog electromechanical transducer that produces a rotary deflection or some type of pointer in response to electric current flowing through its coil. The Galvanometer  330  reflects and actuates the laser beam and accurately projects the laser beam on to the ground or other surface. The projected position of the laser beam is vertically moved and accurately controlled by the Galvanometer  330 . The laser beam is actuated to draw a laser line on the ground or other surface. First Laser Projector  110  produces First Laser Line  170  and Second Laser Projector  120  produces Second Laser Line  180 . When the Rotation Assembly  230  and Top Cover  220  are pivoted with respect to Base Housing  240 , the laser beam is still accurately projected on the ground or other surface, and the projected position of the laser beam is horizontally moved. By both moving the laser beam vertically with the Galvanometer  330  and horizontally with the Rotation Assembly  230 , First Laser Line  170  and Second Laser Line  180  are accurately projected to create Specified Location  190 . 
         [0064]    In more detail, referring to  FIG. 1  in order to accurately calculate and identify the specified placement of First Laser Line  170  and Second Laser Line  180 , and furthermore identify Specified Location  190 , it is necessary to define the intersecting location for the First Laser Line  170  and the Second Laser Line  180 . The intersecting laser lines are used to identify the position of Specified Location  190  by fixing its position relative to two or more mapped or known points, and the starting position of First Laser Projector  110  and Second Laser Projector  120 . The Observation of angles made at unknown points is referred to as resection. Resection simply reverses the intersection process by using crossed back bearings, where the starting position is the unknown. Two or more bearings to mapped, known points are taken; their resultant lines of position drawn from the known points to where they intersect will reveal the starting position of First Laser Line  170  and Second Laser Line  180 , or the location of Laser Projector  110  and Laser Projector  120 . 
         [0065]      FIG. 5  illustrates the formula or problem in planar surveying used to calculate the position of First and Second Laser Projectors  110  and  120  and the specified location  190 . As Illustrated in  FIG. 5  there are two known points A and B, and two unknown points P 1  and P 2 . P 1  and P 2  represent First and Second Laser Projectors  110  and  120 . Points A and B are locations that have been identified prior to starting the calculations and prior using the specified formula. An example of point A and B is the corner of a defined property or construction lot and an identified point that is a measured distance from the corner of the defined property or construction lot. From P 1  and P 2  an observer measures the angles made by the lines of sight to each of the other three points. The problem is to find the positions of P 1  and P 2 . The angles measured are (α 1 , β 1 , α 2 , β 2 ). Since it involves observations of angles made at unknown points, the problem is an example of resection. 
         [0066]    In one embodiment of the present invention the process for measuring the angles is accomplished by first targeting Laser Projector  110  and Laser Projector  120  toward each other. In reference to  FIG. 5 , Laser Projector  110  is represented by P 1  and Laser Projector  120  is represented by P 2 . Targeting First Laser Projector  110  and Second Laser Projector  120  toward each other creates reference angles for both First Laser Projector  110  and Second Laser Projector  120 . The Light Detector  360  located in First Laser Projector  110  is able to detect the laser beam targeted from Second Laser Projector  120 . The Light Detector  360  located in Second Laser Projector  110  is able to detect the laser beam targeted from First Laser Projector  110 . When the Light Detector  360  located in both First Laser Projector  110  and Second Laser Projector  120  have simultaneously detected laser beams from the corresponding Laser Projectors, it is known that the Laser Projectors are oriented correctly and the correct reference angle has been created. 
         [0067]    In further reference to  FIG. 5 , once the reference angle is identified and recorded, the coordinates for known locations A and B can be identified and recorded. This is accomplished by first intersecting First Laser Line  170  and Second Laser Line  180  over known point A and recording the angles η and β 2 . Once point A is identified and recorded, point B can be identified by intersecting First Laser Line  170  and Second Laser Line  180  over the known point B and recording the angles ν and β 1 . 
         [0068]    In further reference to  FIG. 5 , once the reference angles and the coordinates for the two known locations are identified and recorded, it is possible to calculate the location of P 1  and P 2 . In order to identify positions P 1  and P 2  we must first define the following angles: γ=P 1 AP 2 , δ=P 1 BP 2 , φ=P 2 AB, ψ=P 1 BA. As a first step we will solve for φ and ψ. The sum of these two unknown angles is equal to the sum of β 1  and β 2 , yielding the following equation: φ+ψ=β 1 +β 2 : 
         [0000]    A second equation can be found as follows. The law of sines yields 
         [0000]    
       
         
           
             
               AB 
               
                 
                   P 
                   2 
                 
                  
                 B 
               
             
             = 
             
               
                 sin 
                  
                 
                     
                 
                  
                 
                   α 
                   2 
                 
               
               
                 sin 
                  
                 
                     
                 
                  
                 φ 
               
             
           
         
       
       
         
           and 
         
       
       
         
           
             
               
                 
                   P 
                   2 
                 
                  
                 B 
               
               
                 
                   P 
                   1 
                 
                  
                 
                   P 
                   2 
                 
               
             
             = 
             
               
                 sin 
                  
                 
                     
                 
                  
                 
                   β 
                   1 
                 
               
               
                 sin 
                  
                 
                     
                 
                  
                 δ 
               
             
           
         
       
     
         [0000]    combining these together we get 
         [0000]    
       
         
           
             
               AB 
               
                 
                   P 
                   1 
                 
                  
                 
                   P 
                   2 
                 
               
             
             = 
             
               
                 sin 
                  
                 
                     
                 
                  
                 
                   α 
                   2 
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   β 
                   1 
                 
               
               
                 sin 
                  
                 
                     
                 
                  
                 φ 
                  
                 
                     
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 δ 
               
             
           
         
       
     
         [0000]    An entirely analogous reasoning on the other side yields 
         [0000]    
       
         
           
             
               AB 
               
                 
                   P 
                   1 
                 
                  
                 
                   P 
                   2 
                 
               
             
             = 
             
               
                 sin 
                  
                 
                     
                 
                  
                 
                   α 
                   1 
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   β 
                   2 
                 
               
               
                 sin 
                  
                 
                     
                 
                  
                 ψ 
                  
                 
                     
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 γ 
               
             
           
         
       
     
         [0000]    Setting these two equal gives 
         [0000]    
       
         
           
             
               
                 sin 
                  
                 
                     
                 
                  
                 φ 
               
               
                 sin 
                  
                 
                     
                 
                  
                 ψ 
               
             
             = 
             
               
                 
                   sin 
                    
                   
                       
                   
                    
                   γ 
                    
                   
                       
                   
                    
                   sin 
                    
                   
                       
                   
                    
                   
                     α 
                     2 
                   
                    
                   sin 
                    
                   
                       
                   
                    
                   
                     β 
                     1 
                   
                 
                 
                   sin 
                    
                   
                       
                   
                    
                   δ 
                    
                   
                       
                   
                    
                   sin 
                    
                   
                       
                   
                    
                   
                     α 
                     1 
                   
                    
                   sin 
                    
                   
                       
                   
                    
                   
                     β 
                     2 
                   
                 
               
               = 
               k 
             
           
         
       
     
         [0000]    Using a known trigonometric identity this ratio of sines can be expressed as the tangent of an angle difference: 
         [0000]    
       
         
           
             
               tan 
                
               
                 
                   φ 
                   - 
                   ψ 
                 
                 2 
               
             
             = 
             
               
                 
                   k 
                   - 
                   1 
                 
                 
                   k 
                   + 
                   1 
                 
               
                
               tan 
                
               
                 
                   φ 
                   + 
                   ψ 
                 
                 2 
               
             
           
         
       
     
         [0000]    This is the second equation we need. Once we solve the two equations for the two unknowns φ and ψ, we can use either of the two expressions above for 
         [0000]    
       
         
           
             AB 
             
               
                 P 
                 1 
               
                
               
                 P 
                 2 
               
             
           
         
       
     
         [0000]    to find P 1 P 2  since AB is known. We can then find all specified locations using the law of sines.
 
When the four angles (α 1 , β 1 , α 2 , β 2 ) and the distance AB are provided the calculation proceeds as follows:
 
         [0000]    
       
         
           
             
               
                 Calculate 
                  
                 
                     
                 
                  
                 γ 
               
               = 
               
                 π 
                 - 
                 
                   α 
                   1 
                 
                 - 
                 
                   β 
                   1 
                 
                 - 
                 
                   β 
                   2 
                 
               
             
             , 
             
               δ 
               = 
               
                 π 
                 - 
                 
                   α 
                   2 
                 
                 - 
                 
                   β 
                   1 
                 
                 - 
                 
                   β 
                   2 
                 
               
             
           
         
       
       
         
           
             
               Calculate 
                
               
                   
               
                
               k 
             
             = 
             
               
                 sin 
                  
                 
                     
                 
                  
                 γ 
                  
                 
                     
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   α 
                   2 
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   β 
                   1 
                 
               
               
                 sin 
                  
                 
                     
                 
                  
                 δ 
                  
                 
                     
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   α 
                   1 
                 
                  
                 sin 
                  
                 
                     
                 
                  
                 
                   β 
                   2 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   Let 
                    
                   
                       
                   
                    
                   s 
                 
                 = 
                 
                   
                     β 
                     1 
                   
                   + 
                   
                     β 
                     2 
                   
                 
               
               , 
               
                 d 
                 = 
                 
                   2 
                    
                   
                       
                   
                    
                   arc 
                    
                   
                       
                   
                    
                   
                     tan 
                      
                     
                       [ 
                       
                         
                           
                             k 
                             - 
                             1 
                           
                           
                             k 
                             + 
                             1 
                           
                         
                          
                         
                           tan 
                            
                           
                             ( 
                             
                               s 
                               / 
                               2 
                             
                             ) 
                           
                         
                       
                       ] 
                     
                   
                    
                   
                       
                   
                    
                   and 
                    
                   
                       
                   
                    
                   then 
                 
               
             
              
             
                 
             
           
         
       
       
         
           
             
               ϕ 
               = 
               
                 
                   ( 
                   
                     s 
                     + 
                     d 
                   
                   ) 
                 
                 / 
                 2 
               
             
             , 
             
               ψ 
               = 
               
                 
                   ( 
                   
                     s 
                     - 
                     d 
                   
                   ) 
                 
                 / 
                 2. 
               
             
           
         
       
       
         
           Calculate 
         
       
       
         
           
             
               
                 
                   P 
                   1 
                 
                  
                 
                   P 
                   2 
                 
               
               = 
               
                 AB 
                  
                 
                   
                     sin 
                      
                     
                         
                     
                      
                     φ 
                      
                     
                         
                     
                      
                     sin 
                      
                     
                         
                     
                      
                     δ 
                   
                   
                     sin 
                      
                     
                         
                     
                      
                     
                       α 
                       2 
                     
                      
                     sin 
                      
                     
                         
                     
                      
                     
                       β 
                       1 
                     
                   
                 
               
             
             , 
             
               
 
             
              
             
               or 
                
               
                   
               
                
               equivalently 
             
             , 
             
               
 
             
              
             
               
                 
                   P 
                   1 
                 
                  
                 
                   P 
                   2 
                 
               
               = 
               
                 AB 
                  
                 
                   
                     sin 
                      
                     
                         
                     
                      
                     ψ 
                      
                     
                         
                     
                      
                     sin 
                      
                     
                         
                     
                      
                     γ 
                   
                   
                     sin 
                      
                     
                         
                     
                      
                     
                       α 
                       1 
                     
                      
                     sin 
                      
                     
                         
                     
                      
                     
                       β 
                       2 
                     
                   
                 
               
             
             , 
           
         
       
     
         [0000]    If one of these fractions has a denominator close to zero, use the other one. 
         [0069]    Once a known angle, two or more known coordinates and the positions of First Laser Projector  110  and Second Laser Projector  120  have been calculated, identified and recorded, it is then possible to accurately calculate, identify and record any number of additional specified locations. In order to calculate, identify and record additional locations, it is necessary to calculate and record the inverse of the X and Y coordinates for each additional targeted location. The angles X and Y, or analog data are then stored in Data Collector  195  and can be used by Single Board Computer  310  to control the driving and adjustment devices accordingly. The angles represent a reference to the horizontal and vertical angle measuring devices used in First Laser Projectors  110  and Second Laser Projector  120  and relate to the traditional optical or sighting of First Laser Line  170  or Second Laser Line  180 . 
       ADVANTAGES OF THE INVENTION 
       [0070]    From the description above, the advantages of the present invention include, without limitation:
       a) The apparatus and method can accurately calculate and identify specified locations without the use of a stadia rod or prism.   b) The apparatus and method requires only one person to operate.   c) The apparatus and method utilize visible laser beams that are actuated to draw a line for better operator visibility.   d) The apparatus and method utilize two or more laser lines that intersect at specified locations for simplified position identification.   e) The apparatus and method reduces potential measurement error by minimizing the required amount of human measurement and calculation.   f) The apparatus and method automatically compensates for uneven terrain and allows the user to accurately measure X and Y distance over variation in elevation.   g) The apparatus and method requires minimal training.       
 
       CONCLUSION, RAMIFICATIONS, AND SCOPE 
       [0078]    In broad embodiment, the present invention provides a unique optical instrument for identifying specified locations. The present system is primarily comprised of solid state devices for ease of operation and maintenance, while providing continuously accurate operation. The present system is controlled using a wireless handheld device or data collector. When turned on, the referenced Laser Projectors and Data Collector automatically connect and established an independent wireless network. When used as a surveying system, the present invention may eliminate required operators while yet providing accurate coordinate data. The present system minimizes the need for individual measurement, and therefore reduces the opportunity for human error. The present system uses two or more visible laser lines that intersect at specified locations. Furthermore, the present invention has additional advantages that:
       Can be used as a surveying system to identify key locations.   Can be used in Civil Engineering to coordinate and layout roads, trails, and buildings.   Can be used in construction to identify the location of framing, plumbing, electrical, tile, decks and patios, or fences.   Can be used for assembly line placement, shop layout, interior rack or storage layout, or identifying the location and placement of objects or workspace within a defined space.   Can be used with large scale paint templates and assist the placement of large logos, or the generation of graphics on pools, equipment or buildings.   Although the use of two Laser Projectors has been described in the embodiment illustrated in  FIG. 1 , the Laser Projectors may be used independently or with more than two, if so desired.       
 
         [0085]    It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms which the appended claims are expressed. Thus the scope of the embodiments should be determined by the appended claims and their legal equivalents, rather than by the examples given.