JPS62179675A - System for measuring three-dimensional position of vehicle - Google Patents

Abstract

PURPOSE:To obtain the position of a vehicle, by a method wherein a non-directional pulse transmitter and a laser beam emitter rotating at a constant speed in synchronous relation to said transmitter are arranged at reference positions of two places so as to be set at the same height above the ground and laser beam is received at the almost center on the surface of the square pillar shaped laser beam receiver which is arranged on the vehicle and of which an axis is always kept vertical. CONSTITUTION:Laser beam emits a pulse when it turns to north. When times required in drawing receiving laser beam wave forms after the reception of the pulse are set to ta1, ta2 and the time up to the reception of the next pulse to Ta, a y-axis is directed to north and azimuth angles alpha, beta at positions A, B can be calculated. If the azimuth angles alpha, beta are known, the coordinates x, y of a vehicle position P can be calculated. The coordinates (z) of a point P is set to the center h0 of a beam receiving part in a height direction and laser beams from points A, B having the same height from the ground are regulated by the posture control apparatus of a beam receiver to calculate z=h0+h. By this constitution, the positions of a plurality of construction vehicles frequency changing a running road and present on the spot of an unlevelled area are measured to enable the allocation of vehicles.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for measuring the position of a vehicle, and is particularly suitable for measuring the position of a construction vehicle at a civil engineering work site where the vehicle travel path changes frequently and the road surface is not leveled. It is suitable for use.

(Prior Art) Conventional methods for measuring the position of a running vehicle are classified as follows. That is, (A) a method in which a traveling vehicle detects its position using an external support facility.

(A)-(1) Fixed route method: Guides the vehicle using a cable buried in the running track or an optical tape fixed on the running track, or by a laser beam emitted along the running track. A method of guiding moving vehicles.

(A)-(2) Semi-fixed route method: A method in which the vehicle is guided using marks placed on the road surface of the vehicle.

(A)-(3) Free route method: A method that guides a free route while measuring the direction and distance from the reference point of an external support facility to the traveling vehicle. Radio waves, lasers, or ultrasonic waves are used, and there are the following two measurement methods. In other words, (A)-(3)-<i) Arc method...Figure 8 (
In a), a and b are two reference points on the ground, and p is the position of the vehicle whose position is to be measured.

- As an example, a case using radio waves will be explained.

Radio waves are transmitted from point P and received at points A and B.

If you reply at the same time as receiving and receive this at point p.

The position of point p is determined by measuring the time taken for the radio waves to travel back and forth between pa and pb.

(A) - (3) (ii) Hyperbolic method...
- In FIG. 8(b), a, b, and C are three reference points on the ground, and p is the position of the vehicle whose position is to be measured. - As an example, a case using radio waves will be explained.

If radio waves are transmitted at points a and b at the same time T0 and received at point p at times T and Tb, the following equation holds true, where ■ is the propagation speed of the radio waves.

Distance between pa L, = V (T, To)---11)
Distance between pb Lb=V(T, -T,)・−・−・・(
2) Therefore, L, -Lb=V(T, -Tb) -...
(3) If we measure T, -T, using equation (3), -L
.

can be calculated. Since the locus of a point whose distance from two fixed points is constant is a hyperbola with the two fixed points as focal points, point p is one hyperbola with focal points at points a and b (see Figure 8). 5abp) of b). If similar measurements are made for points a and C, point p will be a hyperbola with focal points at points a and C (811 in Figure 8(b)).
The position of point p is determined as the intersection of the hyperbolas S ahp and S acp. (However, there are two points of intersection between the two hyperbolas, but the measurer only has to select one point that is close to the estimated position.) (B) Rotation of the wheels of the traveling vehicle without using external support facilities and mounting on the traveling vehicle A system in which a traveling vehicle independently measures distance and direction using a gyro (problem to be solved by the invention) At a civil engineering work site where construction vehicles are operated, (a) the route of the construction vehicle changes frequently; 9(b) Among the position measurement methods described above (prior art), there is an adverse condition that the road surface for construction vehicles is not leveled.

The (A)-(1) fixed route method and the (A)-(2) semi-fixed route method cannot be used due to the condition (a) that the route of the construction vehicle changes frequently. In addition, the above (B) position measurement method in which the running vehicle is independent without using external support facilities,
Since the errors are accumulated, it is very difficult to apply this method to civil engineering work sites due to the condition (b) that the road surface for construction vehicles is not leveled.

Of the position needle measurement methods mentioned above (prior technology), the free path method (A)-(3) is practical at civil engineering work sites, but among the measurement methods, the conventional method using radio waves is This type is suitable for long-distance and large-scale applications such as ships, but it is expensive and its positioning accuracy is not very good. Additionally, there are the following problems with the measurement method.

(A) - (3) - (i) The arc method can only perform positioning of one construction vehicle with respect to two reference points.

(A) - (3) - (ii) The hyperbolic method is capable of positioning multiple construction vehicles, but it requires three reference points, and between the reference points (point a in Figure 8(b) and This method has the problem of being complicated and expensive because it requires synchronization at point b, point a, and point C).

Furthermore, another problem is that another measuring means is required to measure the position in the height direction, making the overall configuration complicated.

(Means and effects for solving the problem) A wireless transmitter that transmits omnidirectional pulse signals to two reference points on the ground, and a laser that emits light that rotates at a constant speed in synchronization with the pulse signals. A vessel.

The two locations are installed so that the heights of the laser beams from the ground are the same. In this way, for example, if a pulse signal is transmitted when the laser beam is directed north, the angle information +a from the north is imparted to the laser beam.

A laser receiver with an omnidirectional 1, for example, a regular polygonal prism light-receiving surface is installed in a clear line-of-sight position on the vehicle whose position is to be measured, and the light-receiving surface is always fixed regardless of the vehicle's inclination. A laser receiver is installed on the vehicle via an attitude control device so that it is vertical and the laser light receiving position is at a height approximately at the center of the light receiving surface.

In this way, two azimuth angle data can be obtained from the two laser beams received by the on-vehicle laser receiver, and the position of the vehicle can be determined from this and the distances between the two laser emitters. can do. Furthermore, the height of the vehicle can be determined by measuring the leg length of the attitude control device on which the laser receiver is placed.

As described above, in this invention, for two reference points,
It is capable of measuring the three-dimensional positions of multiple moving vehicles.

(Example) Examples of the present invention will be described below based on the drawings.

FIG. 2 is a schematic diagram of a specific example of a laser emitting device 20. A laser emitting device 21 is rotatable in a housing 24 having two legs 25 via a turntable 22 rotated at a constant speed by a motor 23. It is pivoted like this. 0 indicates the rotation center line of the laser emitter 21. Reference numeral 28 denotes a proximity switch, which is set so that when the laser beam emitted from the laser emitter 21 faces a reference direction, for example north, the proximity switch 28 is turned on, and at that time it transmits a pulse to the omnidirectional transmitter 26. It is designed to give a trigger. 27 is an electric cable connecting the proximity switch 28 and the omnidirectional transmitter 26. Incidentally, the laser beams and pulse signals emitted from the two laser emitting devices set at two reference positions are changed in frequency (9) phase and wavelength (9) intensity so that they can be discriminated from each other. In addition, the legs 25 of the two laser emitting devices 20
The two laser emitting devices 2 are adjusted so that the rotation center lines O of the laser emitting devices 21 are perpendicular to each other and the heights of the two laser beams from the ground are the same.
0 on the ground.

FIG. 3 is a schematic diagram of a specific example of a laser light receiving device 30. In FIG.
n≧3), and FIG. 9 shows a regular triangular prism structure. The light-receiving surface of this laser light-receiving section 31 is as follows.

Attitude control device! 32, when the laser light receiving device 30 is mounted on a vehicle, it is configured to always be vertical regardless of the inclination of the vehicle or the unevenness of the ground.

FIG. 1 is an explanatory diagram of a vehicle position calculation method according to the present invention.

In the figure, A and B indicate the positions of the laser emitting device 20 installed at two reference points on the ground, and each corresponds to O in FIG. 2. P indicates the position of the laser light receiving device 30 installed on the vehicle whose position is to be measured;
This corresponds to the axial center of the regular triangular prism of the laser light receiving section 31 in FIG. In Figure 1, the rectangular coordinate axis with the origin at point A is
-xy, the negative direction of the X axis is north, the sign is as shown in Figure 9, and α and β are determined.

The coordinates x and y of point P are determined by the following equation.

L AP sin (π-(π-α)-β because sin β.

x = AP1 cos (g-a) y = τ 5 in (π-α) Figure 4 shows α and FIG. 3 is an explanatory diagram of an example of a method for measuring β. In FIG. 4(a), the horizontal axis represents the time when the laser beam and pulse signal from point A are received at point P, and the vertical axis represents the electrical waveforms of the laser beam and pulse signal. Now, the time from receiving the pulse signal to the rise and fall of the received laser waveform is tll +
and tmt, and the time taken to receive the 9th pulse signal is T. As explained in FIG. 2, T1 is the rotation period of the laser emitter at point A, and in this embodiment, the laser When the light is emitted to the north, a pulse signal is emitted.

Figure 4(b) shows the laser beam and pulse signal from point B at P
+ tbl + 'bZ and T
, respectively, are L II+ ta2 and T in FIG. 4+a).

corresponds to

Based on the above description, the azimuth angles α and β in FIG. 1 can be obtained using the following equations.

Therefore, the coordinates X and y of point P are the values of α and β above,
It can be found by putting it into equations (4) and (5).

The height direction coordinate value 2 of point P is obtained in the 9th order. That is, the center position in the height direction of the laser light receiving part (31 in Fig. 3) is set to ho in advance, and points A and B are set in advance.
The two emitted laser beams from the point are at the same height from the ground as explained in FIG.
Since the leg length of the posture control device (32 in FIG. 3) is adjusted, let the amount of change in the leg length be h (more specifically, the average value of the length adjustment amounts of the four legs of the posture control device).

z=h, +h −・−m−−−−・・−・・−・−・
−・・−・−・−・−・It is obtained by (8).

FIG. 5 is a specific example of a block diagram of a light-receiving laser arithmetic processing according to the present invention. The laser light that enters the laser light receiving point is converted into electric current by the light receiving element.

The current values correspond to the lengths of the upper part (H) and lower part (L) of the laser light receiving section 31, respectively, and the "current-voltage converter 51"
and 52, and are converted into corresponding voltage values and sent to BPFs (band pass filters) 53, 54.55 and 5.
Enter 6. 53 and 55 are BPFs that process the laser beam from point A, and 54 and 56 are BPFs that process the laser beam from point B.

Additionally, as mentioned in the explanation of Fig. 2 above, A
The laser beam and pulse signal emitted from point and point B are
The above four B items are designed to be able to be distinguished from each other.
Only the differentiated voltages enter the PF. The voltages output from the BPF are respectively connected to the current circuit 5.
7°58, 59.60 and LPF (low pass filter)
The necessary electrical processing is performed at 61°62, 63.64, and the voltage value vHa+ Vllb+ VLan V Lb
is obtained.

FIG. 6 is a schematic explanatory diagram of a specific example of the present invention at a civil engineering work site. In the figure, 71 and 72 are both construction vehicles undergoing civil engineering work, and 73 and 74 are the laser emitting devices explained in FIG. 2.

It is installed at two points that serve as the reference for position measurement on the ground.

In addition, the two light emitting lasers are installed with their respective leg lengths adjusted so that their heights above the ground are the same. Both 75 and 76 are the omnidirectional transmitters described in FIG. 77 and 7 are both the laser receivers explained in FIG. 3, and 79 and 80 are both radio devices, and the transmitter 75
and 76, and communicates with a radio device 83 connected to a vehicle position management device 82 installed in a work site management office 81. In the vehicle management device 82, for example, the construction vehicle 71
When the position reading of the construction vehicle 72 is completed, the position reading of the construction vehicle 72 is first carried out.

FIG. 7 is a block diagram of an example of an integrated system for measuring the position of the construction vehicle 71 in FIG. 6, for example. construction vehicle 7
1 tilts due to the inclination or unevenness of the road surface, the inclinometer 91 (
Signals from two sets (one for the longitudinal direction and one for the lateral direction of the vehicle) are sent via the arithmetic circuit 92 to actuate the actuating member of the attitude control device 32 so that the light-receiving surface of the laser light-receiving section 31 is always maintained vertically. It has become. Since the other parts shown in FIG. 7 have already been explained or consist of a combination of conventional techniques, their explanation will be omitted.

(Effects of the Invention) Since the present invention is constructed as described above, it is possible to avoid problems such as at a civil engineering work site where construction vehicles operate (a) where the vehicle travels frequently, and (b) where the vehicle travels on an uneven surface.

Even under these adverse conditions, simply installing laser emitting devices at two reference points makes it possible to easily and inexpensively measure the positions of a plurality of vehicles equipped with laser light receiving devices.

Furthermore, the information in the height direction of the work vehicle is directly related to the flatness of the leveled surface especially in civil engineering work, and the progress status of the work can be grasped, so it can be expected to improve the efficiency of vehicle allocation work. Furthermore.

Since a single work site management office can grasp the location of multiple work vehicles over a wide area, it is possible to issue appropriate work instructions, greatly improving the efficiency and ensuring safety of a single work.

Furthermore, it is expected that the work will become unmanned, which is an excellent result.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the vehicle position calculation method of the present invention, Fig. 2 is a schematic diagram of a specific example of a laser emitting device, Fig. 3 is a schematic diagram of an example of a laser receiving device, and Fig. 4 (a) and (b)
FIG. 2 is an explanatory diagram showing the relationship between the electrical waveforms of laser light and pulse signals and reception times in a vehicle that attempts to measure one position. FIG. 5 is a specific example of a light receiving laser calculation processing block diagram, FIG. 6 is a schematic explanatory diagram of a specific example of the present invention at a civil engineering work site, and FIG. 7 is a position measurement of the construction vehicle 71 in FIG. 6. FIG. 8 is a block diagram of a specific example of the case (al and (bl are explanatory diagrams of the arc method and hyperbolic method of the free path method, respectively, among the position measurement methods of the prior art. 20... Laser emitting device , 21... Laser emitter. 22... Turntable, 25... Legs. 26... Omnidirectional transmitter, 30... Laser receiver. 31... Laser receiver, 32... ...Attitude control device. Patent applicant Komatsu Ltd. Agent (patent attorney) Osamu Matsuzawa Figure 1 Figure 2 Figure 3 Figure 4 (Q) 4th WJ (b) Q, 1, Sachugoto Filling 8 Figure (0) Figure 8 (b)

Claims (1)

[Claims] A laser emitting device installed at two reference positions, each consisting of a laser emitting device, legs and a turntable that rotate the laser beam at a constant speed in a horizontal plane, and an omnidirectional transmitter that transmits a reference azimuth signal. and; a laser light receiving part having a laser light receiving plate attached on a polygonal prism surface so that the laser light from the laser emitting device can be received in all directions, and the laser light receiving part is maintained vertically regardless of the posture of the vehicle. 1. A vehicle position measuring method comprising: an on-vehicle laser emitting device comprising: and an attitude control device that always keeps the height of the laser light receiving section from the ground constant.