JP2827048B2 - Distance measuring device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring device capable of obtaining a wide distance measuring range from a very short distance to a long distance with one distance measuring device, and in particular, to a measuring device. The present invention relates to a distance measuring device that measures a distance to a reference wall surface or the like, and can be suitably adopted for an omnidirectional mobile trolley or the like that autonomously travels based on the distance.

[Prior Art] Conventionally, as shown in FIG. 7, the principle of triangulation is applied to apply an infrared ray from a LED to an object O to be measured through a lens R1 through a lens R1, and the reflected light is applied to a light receiving lens R2. There is an optical distance measuring sensor S1 that receives light by a position sensor P through the sensor and calculates the following formula based on the condensing position to derive the distance to the object O.

L = fB / x, where L: distance to the object to be measured B: reference length x: focus position from the center of the light receiving lens R2 f: focal length of the light receiving lens R2 However, the distance measuring sensor S1 is shown in FIG. As shown by the two-dot chain line, when the object O is located at a close distance, the light condensing position of the reflected light is outside the detection area of the position sensor P, so that the light cannot be condensed and the distance measurement is performed. Impossible.

In order to eliminate this defect, there is a distance measuring sensor S2 in which the light receiving lens R2 and the position sensor P are arranged so as to be inclined toward the lens R1 as shown in FIG. According to the distance measuring sensor S2, even if the object to be measured O exists at a close distance, the condensing position of the reflected light can be located within the position detection area of the position sensor P. It is used as a distance measurement sensor dedicated to distance.

The use of the distance measuring sensor S1 or the distance measuring sensor S2 or the like has been aimed at automation and unmanned operation in various industries. Above all, transport vehicles such as unmanned vehicles and omni-directional vehicles that transport workpieces and the like in unmanned warehouses and the like, as shown in FIG.
The distance d1 and d2 are obtained by performing distance measurement from two sides from one side of the vehicle, and the distance S between distance measurement is used to calculate the attitude angle ψ of the vehicle body V and the like. To maintain a good stopping position and traveling route. As described above, the distance measuring sensor is indispensable as means for causing the transport vehicle to accurately recognize the current position.

[Problem to be Solved by the Invention] An unmanned traveling vehicle that transports a work in the unmanned warehouse or the like described above,
In transport vehicles such as omnidirectional vehicles, loading of workpieces,
At the time of unloading and stopping positioning, it is necessary to approach a station or the like, and the ranging range is very wide. However, since the distance measuring sensor S1 is for a long distance to a medium distance, and the distance measuring sensor S2 is different for a close distance and a range for individually measuring the distance,
When ranging over a wide range from a long distance to a close distance is required, both ranging devices must be used, which is extremely uneconomical.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-described problem and to provide a distance measuring apparatus capable of obtaining a wide distance measuring distance from a very short distance to a long distance with one distance measuring apparatus.

Means for Solving the Problems In view of the above problems, the present invention provides an optical system that emits search light to an object to be measured, receives reflected search light, and detects the distance to the object to be measured. A distance measuring unit, a first reflector that reflects the search light emitted from the optical distance measurement unit at a right angle, and a search light that is on the object side and reflected by the first reflector. Second reflection at right angle
A third reflector that further reflects the search light reflected by the second reflector toward the optical distance measuring device at a right angle, and a probe that reflects the search light reflected by the third reflector. A fourth reflector on the object to be measured and reflecting at a right angle so that the optical distance measuring means coincides with the axis from which the search light is emitted; and a bracket for integrally fixing the first and fourth reflectors. The bracket is provided so as to be slidable along a horizontal axis parallel to the surface of the measuring head, and further includes a translation drive means capable of translating the bracket.

[Embodiment] Figs. 1, 2 and 3 show an embodiment of the present invention.
Is a distance measuring device according to the present invention, which comprises an optical distance measuring sensor 2 on a substrate 10, a bracket 3, a linear guide mechanism 31 fixed to the lower surface of the bracket 3, and a linear guide mechanism 31.
And a translation drive means 8 for disposing the first, second, third and fourth reflectors 4, 5, 6, and 7 and for translating the bracket 3 in parallel. Equipped.

As shown in FIG. 3, the optical distance measuring sensor includes a light receiving unit 23 which emits search light from a light emitting unit 22 to a distance measuring head surface 21 and receives reflected light of the search light reflected on an object to be measured. Is used.

The bracket 3 has a substantially "L" shape, and a linear guide mechanism 31 such as a linear motion bearing having a ball bearing is fixed to a lower surface of the bracket 3 along a guide portion 32 fixed to an upper surface of the substrate 10. Thus, it is slidably guided with respect to the substrate 10. A first reflector 4 (hereinafter, simply referred to as a reflector 4) and a fourth reflector 7 (hereinafter, simply referred to as a reflector 7) are fixed to an upper surface of the bracket 3 and the optical distance measuring sensor 2 side. I have.

Further, the second reflector 5 (hereinafter simply referred to as the reflector 5) and the third reflector 6 (hereinafter simply referred to as the reflector 6) are opposite to the side of the substrate 10 where the optical distance measuring sensor 2 is disposed. The reflector bracket 12 is positioned on the side and at a position where the reflectors 4 and 7 are translated.
Fixed through.

When the above positional relationships of the reflectors are arranged based on FIG. 5, the reflectors 4 are arranged so as to reflect the search light emitted from the optical distance measuring means at right angles and to the right (in the figure). . The reflector 5 is provided with the reflector 4.
Are arranged so as to reflect the reflected search light at right angles and downward (in the figure). Further, the reflector 6 receives the search light reflected by the reflector 5 and is arranged so as to be reflected at a right angle and to the left. The reflector 7 is disposed so as to reflect the search light reflected by the reflector 6 on the measured object O side and at a right angle so as to be coincident with the axis from which the optical distance measuring sensor 2 emits the search light. I have.

Next, as shown in FIG. 3, the parallel movement driving means 8 turns on the rotation axis which is the output shaft by exciting the coil 85.
A rotary solenoid 81 that rotates 82, a rotary piece 83 fixed to the rotary shaft 82 of the rotary solenoid 81, and a link that is pivotally connected to one end of the rotary piece 83 by a pin so as to be rotatable. 84
And one end of the link 84 can be pivotally supported on the upper surface of the bracket 3 by a pin. Therefore, when the coil 85 of the rotary solenoid 81 is excited, the rotation shaft 82 and the rotation piece 83 rotate and act on the link 84, so that the bracket 3 can slide. The bracket 3 can be slid in any direction by changing the direction of the current that excites the coil 85.

Reference numeral 11 denotes a stopper pin fixed to the substrate 10, which restricts the rotation piece 83 to a predetermined rotation angle in order to limit the amount of movement of the bracket 3 which can be slid by the translation drive means 8. Things.

[Operation] The operation of the present invention will be described below with reference to FIGS. 4 and 5.

FIG. 4 shows a case where the object to be measured O is present at a relatively long distance. In this case, the coil 85 of the rotary solenoid 81 and the turning piece 83 turn counterclockwise about the turning shaft 82. And the bracket 3 is slid to the right in the drawing. In this state, the optical distance measuring sensor 2
The search light emitted from the light emitting unit 22 travels straight and is reflected by the object O, and the light emitting unit 23 emits the reflected light, so that the distance from the object O can be measured.

On the other hand, FIG. 5 shows a state of the distance measuring apparatus 1 when the object to be measured O is at a close distance. In this case, the coil 85 of the rotary solenoid 81 and the rotating piece 83 are connected to the rotating shaft 82. And the bracket 3 is slid to the left in the drawing. In this state, the light emitted from the light emitting unit 22 of the optical distance measuring sensor 2 is sequentially reflected by the reflector 4 → reflector 5 → reflector 6 → reflector 7 and reaches the object O to be measured. Further, the reflected light that reaches the object O and is reflected is reflected by the reflector 7 →
The light is sequentially reflected by the reflector 6 → the reflector 5 → the reflector 4, received by the light receiving unit 23, and the distance to the object O can be measured.

That is, when the measured object O is located at a close distance, the reflected light is reflected by the light receiving unit using the reflection of each reflector.
By obtaining a large linear distance to reach the position 23, it becomes possible to position the condensing position of the reflected light within the position detection area of the position sensor (not shown).

Incidentally, a surface reflecting mirror or the like can be suitably used as the reflector. Further, in order to prevent the reflectance of each reflector from being lowered, the distance measuring device may be sealed with a case or the like, and means for shutting off the outside air may be provided. In addition, when each reflector is mounted, since each reflected light is completely received and reflected, it is desirable that the width directions of the reflecting surfaces are made to coincide as shown in FIG.

Further, when the distance is measured via the reflector, this is detected by various sensors or the like, and a value obtained by subtracting the reflection distance by the reflector can be used as the distance measurement data.

[Effects of the Invention] As described in detail above, according to the present invention, a single ranging device can obtain a ranging distance that can be measured over a wide range from a very short distance to a long distance. There is no need to provide individual distance measuring sensors corresponding to the above conditions, which is extremely advantageous in terms of manufacturing costs. Therefore, it can be suitably used as a distance measuring device for a transport vehicle such as an omnidirectional mobile trolley that travels autonomously based on the distance while measuring the distance to a reference wall surface or the like.

[Brief description of the drawings]

FIG. 1 is a plan view of the present invention, FIG.
4 and 5 are plan views for explaining the operation of the present invention, FIG. 6 is a view for explaining a preferable mounting of each reflector, and FIGS. FIG. 8 is a schematic diagram for explaining a conventional distance measuring sensor. FIG. 9 is a plan view showing an example in which a distance measuring sensor is used for an omnidirectional moving vehicle. DESCRIPTION OF SYMBOLS 1 ... Distance measuring device 2 ... Optical distance measuring sensor 3 ... Bracket 31 ... Linear guide mechanism 32 ... Guide part 4, 5, 6, 7 ... Reflector 8 ... Parallel movement drive means 81 ... Rotary Solenoid 82 Rotating shaft 83 Rotating piece 84 Link 85 Coil 9 Reflector bracket 10 Substrate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01C 3/00-3/32

Claims (1)

(57) [Claims] 1. An optical distance measuring means for emitting a search light to an object to be measured and receiving a reflected search light to detect a distance to the object to be measured, and emitted from the optical distance measuring means. A first reflector that reflects the search light at a right angle, a second reflector that is on the side of the object to be measured and reflects the search light reflected by the first reflector further at a right angle, and the second reflector. A third reflector that further reflects the search light reflected by the reflector toward the optical distance measuring means at a right angle, and a search light reflected by the third reflector on the object to be measured and the optical A fourth reflection at a right angle so that the distance measuring means coincides with the axis from which the search light is emitted.
Translation driving means for slidably moving along a horizontal axis parallel to the distance measuring head surface, the bracket being integrally fixed with the first and fourth reflectors, and capable of moving the bracket in parallel. A distance measuring device comprising: