JPS6328269B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a distance measuring device having an automatic collimation function to follow a reflector that moves relative to a distance meter.

A conventionally known optical distance meter irradiates a light beam of a predetermined wavelength onto a reflecting mirror such as a cube corner, and calculates the distance from the amount of phase delay caused in the reflected light. However, since the irradiation angle of the light beam is a small value of "several minutes", it is very difficult to automatically collimate a reflecting mirror that moves relative to the optical distance meter. For example, if the beam spread angle is 3 minutes, the beam will form a circle with a diameter of only 90 cm at a distance of 1 km. Therefore, for example, when it is desired to position a work vessel engaged in offshore construction with high precision (that is, when automatically measuring the distance between a moving work vessel and a reference position), it is necessary to use a light wave distance meter according to the conventional technology. It is impossible to use it alone.

Also known is a method in which a reflecting mirror is also provided with a light emitting function and a light wave distance meter automatically follows the reflecting mirror. However, requiring a separate power source for light emission is not desirable in terms of work efficiency.

On the other hand, while automatically tracking the reflector, for example at sea, the workboat may experience significant unexpected pitching or rolling due to weather conditions.
Automatic tracking may become temporarily unavailable. Under such an abnormal situation, it is necessary to easily and quickly grasp the positional relationship of the light beam emitted by the light wave distance meter with respect to the reflecting mirror, and to return to the normal automatic tracking mode again.

Therefore, an object of the present invention is to use a conventionally used unlit reflector while reducing the "swaying" of the reflector.
The object of the present invention is to provide a distance measuring device with an automatic collimation function that can realistically track the distance.

The distance measuring device according to the present invention includes an automatic collimation laser beam source separate from the distance measuring beam source, and irradiates the laser beam onto a single reflecting mirror (cube corner), Connect the X-Y tracker to the TV camera that should receive the reflected light,
Based on the position of the bright spot appearing on the monitor of the XY tracker, the ``direction of deviation'' of the ranging beam with respect to the reflecting mirror is determined, thereby operating the servo mechanism. The television camera is equipped with a telephoto lens so that the operator can actually see the position of the reflector on a monitor. Furthermore, by attaching a telephoto lens with a zoom function to the television camera, it is possible to freely select the spatial range in which automatic collimation is to be performed. In addition, if the automatic tracking function stops working (that is, if the bright spot disappears from the TV monitor), the control circuit detects this and reduces the magnification of the zoom lens, widening the monitor's field of view and It is possible to automatically return to automatic tracking mode. Alternatively, it is also possible to return to the automatic tracking mode by driving the servo function based on a predefined search program.

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a perspective view showing an optical observation equipment section of a distance measuring device according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a monitor control section according to the same embodiment.

In FIG. 1, the observation equipment section facing the reflecting mirror 2 is mounted on a base 4 fixed to a workbench (or workboat). Moreover, on the horizontal rotating table 8 which changes the horizontal direction with the vertical axis 6 as the base axis,
A rocking table 12 that rotates vertically about a horizontal axis 10 is rotatably mounted. A laser light source 14 for automatic collimation, a television camera 16 for receiving laser light, and a light wave distance meter 18 according to the prior art are horizontally arranged on the rocking table 12. Further, drive motors 20 and 22 are separately provided for rotating the horizontal rotary table 8 and the rocking table 12 to predetermined positions.
Furthermore, a prism 28 and a reflecting mirror 30 are used to make the optical axis 24 of the laser beam emitted by the laser light source 14 and the optical axis 26 of the distance measuring laser parallel.

FIG. 2 shows an X-Y tracker 32, a television/camera monitor 34, a position ball 36 for manually controlling the position of the observation equipment shown in FIG. 1, and a computer for performing predetermined calculations and general control. ting controller 38, camera switching switch 39
is depicted. Here, press the camera switch 39
is a switch for connecting one of the plurality of observation equipment sections to a monitor, and has no direct relation to the present invention.

The X-Y tracker 32 is a type of dynamic displacement measuring device that measures the position of a moving object while monitoring it with a television camera. ) 40 and the reference coordinate origin 42 (corresponding to the collimation direction of the television camera 16). The DC difference signal is generated based on the principle of position measurement using raster scanning,
It can be easily obtained by using a commercially available XY tracker.

FIG. 3 is an electrical block diagram showing the entire distance measuring device shown in FIGS. 1 and 2. FIG. In this figure, a laser beam reflected by a reflecting mirror 2 is converted into a video signal 50 by a television camera 16, and is sent to an X-Y tracker 32 and a television monitor 34.
is transmitted to. The X-Y tracker 32 into which the video signal 50 is introduced performs DC control according to the distance difference between the bright spot 40 on the monitor surface (see FIG. 2) and the reference coordinate origin 42.
Difference signal 52 is sent to servo amplifier 48. Here, the DC difference signal 52 represents the amount of deviation in the X direction and the amount of deviation in the Y direction in the luminance 40.
A manual control signal 54 from a position ball (manual operator) 36 is also applied to the servo amplifier 48 . Position ball 36 is used when manually controlling drive motors 20 and 22, and is not required in normal automatic tracking mode (described later). The servo amplifier 48 is a DC
A motor drive signal 56 is generated in response to the difference signal 52 or the manual control signal 54. Motor drive signal 56
is applied to the drive motors 20 and 22, so that the observation equipment section shown in FIG. 1 is collimated in a predetermined direction. The DC difference signal 52 from the XY tracker 32 is also applied to an automatic tracking controller 58. The controller 58 constantly monitors the level of the DC difference signal 52, and detects the bright spot 40 from the monitor surface.
(See FIG. 2), the search control signal 60 or zooming signal 62 is sent out.
The fact that the bright spot 40 has disappeared from the monitor surface means that the optical axis 24 of the laser beam has not reached the reflecting mirror 2. Such a situation occurs, for example, when a work boat is shaken by large waves. Therefore, the search control signal 60 changes the collimation direction of the device to the left, right, up, and down according to a predetermined program. When the bright spot 40 is captured again within the monitor plane, generation of the above-mentioned search control signal 60 is stopped. The operation after the bright spot 40 disappears from the monitor surface in this way (hereinafter referred to as capture operation mode)
is also accomplished by sending a zooming signal 62 to the television camera 16 in place of the search control signal 60. In this case, the telephoto magnification is continuously lowered by the zoom function of the television camera. Therefore, the field of view displayed on the monitor continuously expands, and at a certain point four bright spots appear on the monitor surface.
0 will appear. After any of the above acquisition operations, closed loop control by the XY tracker 32 and servo amplifier 48 is performed again. A state in which such closed-loop control is performed is called an automatic tracking mode. Note that the transition from the capture operation mode to the automatic tracking mode can also be performed manually using the position ball 36. This manual operation can be performed by the operator while looking at the monitor 34. In addition to the controller 58 described above, the controller 38 includes a calculator 64 with arithmetic functions, and the distance measurement signal 6 obtained from the light wave distance meter 18 is
6 is subjected to various calculations (for example, calculating the position of this device).

Finally, as a summary, the operation of this apparatus will be outlined with reference to FIGS. 1 to 3.

(1) First, the operator operates the position ball 36 while looking at the monitor 34, and puts the brightness 40 due to the laser reflected light into the monitor.

(2) After that, when you switch to automatic tracking mode, the bright spot 4
0 is always displayed in the center of the monitor 34. This is because the closed loop operates so that the DC difference signal 52 becomes zero (automatic tracking mode).

(3) If the device is shaken for some reason and becomes unable to operate in the automatic tracking mode, it automatically switches to the capture mode and the bright spot 40 is automatically captured in the monitor. Note that it is also possible to return the bright spot 40 to the inside of the monitor by manual operation.

As detailed above, according to the present invention, it is possible to provide a distance measuring device that automatically aims at a conventionally used unlit reflector, so it can be used as a useful means for determining the position of a maritime work vessel. obtain.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an optical observation equipment section of a distance measuring device according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a monitor control section according to the same embodiment.
FIG. 3 is an electrical block diagram showing the entire distance measuring device shown in FIGS. 1 and 2. FIG. 2: Reflector, 4: Base, 8: Horizontal rotating table, 1
2: Rocking table, 14: Laser light source, 16: TV
Camera, 18: Lightwave distance meter, 20 and 22: Drive motor, 32: X-Y tracker, 34: TV
Monitor, 36: Position ball (manual operation device), 38: Controller, 39: Camera selection switch.

Claims (1)

[Claims] 1. A laser light source that irradiates a collimating laser beam onto a reflecting mirror, an optical distance meter having a beam optical axis parallel to the laser beam, and monitoring the laser reflected light from the reflecting mirror. the laser light source in response to a differential signal sent from a television camera and an X-Y tracker connected to the television camera;
A distance measuring device comprising a driving means for integrally positioning the camera and the light wave distance meter. 2. The distance measuring device according to claim 1, wherein the driving means includes a manual operating device, and the collimating laser beam is manually controlled via a monitor television of the television camera. . 3. When the television camera becomes unable to monitor the laser reflected light, the zoom magnification of the television camera is lowered to recapture the reflecting mirror within the field of view of the camera. A distance measuring device according to range 1 or 2. 4. Claim 1 or 4, characterized in that the driving means includes a control circuit that performs a predetermined search operation when the television camera is no longer able to monitor the laser reflected light. 2. Distance measuring device according to item 2.