JP2990545B2 - Posture angle correction method for unmanned vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting an attitude angle of an unmanned running vehicle capable of correcting an attitude angle over a long distance with only one attitude angle detector.

[0002]

2. Description of the Related Art Conventionally, in the traveling control of an unmanned traveling vehicle (hereinafter simply referred to as traveling vehicle) which performs autonomous traveling, as a method of detecting a posture angle of a vehicle body, a method of calculating from a gyro or a rolling distance of a wheel is known. Are known. However, since errors are accumulated in these calculated values as the gyro usage time and the traveling distance increase, it is necessary to provide a device for correcting these errors.

[0003] As such means, for example, a reference reflector is installed in a traveling route of a traveling vehicle, and a distance between the reflector and the vehicle body is measured by a range finder to obtain an attitude angle. A method has been proposed in which a predetermined mark is laid on the floor surface, the mater is captured as binary data by an imaging device or the like, and predetermined image processing is performed to determine the attitude angle of the vehicle body.

[0004]

However, the attitude angle correcting means for providing a reflector or a mark on the floor surface is, for example,
It cannot be used for a cleaning robot or the like that reciprocates in a wide area such as a gymnasium or a multipurpose hall and cleans the floor surface, because it becomes an obstacle during traveling. Therefore, when the work area of the cleaning robot is large, the posture angle cannot be corrected over a long distance, and there is a problem that traveling accuracy is reduced. Especially when the traveling vehicle is a cleaning robot,
There is also a disadvantage that an uncleaned area occurs.

The present invention has been made in view of such a problem, and an object of the present invention is to detect the attitude angle of a traveling vehicle even in a place where correction means such as a reflector or a mark cannot be provided on the floor surface. It is an object of the present invention to enable traveling control without reducing traveling accuracy by correcting the attitude angle.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a predetermined
Automated guided vehicle traveling in an area
Light or laser light from the part toward the area
At least one or more light emitters
A first light receiving element and the first light receiving element are provided on a side surface of the unmanned traveling vehicle.
A second light receiving element that receives light in a different direction from the
Beam or light emitted from the projector
One is the first light receiving element and the other is
Light is received by the second light receiving element to detect the attitude angle of the vehicle body
One attitude angle detector is provided, and the one attitude angle detector
Correct the vehicle body posture angle based on the calculated posture angle
It is characterized by the following.

[0007]

The traveling principle of the traveling vehicle according to the present invention will be described. The traveling vehicle obtains its own position and posture angle while traveling by its own traveling program, and travels while feeding back the deviation from the traveling course and the posture angle. Things.

[0008] As described above, the position and the attitude angle are obtained while running according to the own running program, and the vehicle travels while feeding back the deviation from the running course and the attitude angle. Accumulated and deviated from the predetermined traveling course, to correct this, on the traveling course, detect the attitude angle with the attitude angle detector attached to the side of the traveling vehicle the light emitted from the floodlight, The attitude angle detected by the angle detector is feedback-controlled.

The detection of the attitude angle by the attitude angle detector will be described on the basis of what is shown in FIG. 3. When the light emitted from the projector is received by the attitude angle detector, a part of the light is converted into a beam. A part is divided by the splitter and the course is changed downward in FIG. 3, the light is received at a position a from the left end of the first light receiving element, and an electric signal corresponding to the light receiving position is obtained. Light is received at position b from the lower end of the second light receiving element, and an electric signal corresponding to the light receiving position is obtained. These two electric signals are sent to the CPU via the A / D converter to obtain the attitude angle in the attitude angle detection device.

The principle of detecting the attitude angle of the present attitude angle detector is as follows.
As shown in FIG. 3, the light receiving element is provided at a predetermined offset distance from a position where the other first light receiving element is plane-symmetrically moved with the beam splitter as a reference plane.
For example, assuming that the offset distance is c, when a perpendicular is lowered from the light receiving surface at the position shifted plane-symmetrically to the light receiving surface of the first light receiving element, the angle between the perpendicular and the optical path of the light emitted from the projector is an attitude angle. The attitude angle is obtained by a simple trigonometric function. This calculation is performed by the CPU.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall schematic diagram of the present invention, and FIG. 2 is a block diagram showing the same. A predetermined traveling area 1, a traveling vehicle 2 autonomously traveling in the traveling area 1, .. That emit light or laser light (hereinafter simply referred to as light) toward the traveling area 1.

The traveling vehicle 2 detects a rolling distance of a wheel (not shown) by an encoder 11 and calculates its own position and attitude angle θn by a CPU 13 while performing a predetermined traveling based on a predetermined traveling program. A vehicle that can travel on a course without a track is shown. In this example, a vehicle that travels over the entire area based on the reciprocating travel of the travel area 1 is illustrated. In addition, the traveling vehicle 2 is provided with an attitude angle detector 4 that can receive the light 10 of the light projector 3 and measure the attitude angle of the vehicle body. This will be described later.

The light 10 emitted from each projector 3...
Are arranged so as to be orthogonal to an axis 9 corresponding to a long distance in the traveling course of the traveling vehicle 2 (hereinafter, simply referred to as an axis 9). They are arranged at predetermined intervals.

The attitude angle detector 4 includes a box-shaped case 6.
A beam splitter 5 and a pair of one-dimensional light receiving elements (hereinafter simply referred to as light receiving elements) 7 and 8 are arranged therein. When the traveling vehicle 2 has zero attitude angular displacement with respect to the axis 9, the beam splitter 5 is fixed to the case 6 at an angle of 45 degrees with respect to the optical axis emitted by the projector 3. Further, the beam splitter 5
In the figure, a first light receiving element 7 and a second light receiving element 8 are provided in regions orthogonally projected in the vertical direction and the horizontal direction, respectively. As shown in FIG. 3, the second light receiving element 8 is provided at a predetermined offset distance C from a position 7A that is plane-symmetrically moved with the first light receiving element 7 as a beam splitter 5 reference plane. .

An electric signal obtained by each of the first light receiving element 7 and the second light receiving element 8 is sent to the CPU 13 via the A / D converter 12. Further, a signal of the encoder 11 for detecting the traveling distance of the traveling vehicle 2 is input to the CPU 13.

Next, the operation of the embodiment of the present invention will be described. FIG. 4 is a control flowchart of the present embodiment. Based on this, the traveling vehicle 2 initializes the attitude angle θn (θn → 0) at the traveling start point, and then runs the traveling course based on its own traveling program. To travel. At this time, the CPU 13 sequentially calculates the posture angular displacement Δθs of the vehicle body based on the traveling distance detected by the encoder 11 for each sampling time,
Further, the posture angle displacement Δθs is sequentially integrated to obtain a posture angle θn, and the steering circuit 14 controls a control target 15 such as a steering motor to reduce the posture angle θn. Note that “θn”
“N” means a sequential value.

Then, as shown in FIG.
Light emitted from the vehicle is detected by an attitude angle detector 4 provided on the traveling vehicle 2.
Is received by the beam splitter 5.
A part of the light is split and the path is changed downward. The light is received by one of the light receiving elements 7, and the remaining light is transmitted through the beam splitter 5 and received by the other light receiving element 8. Electric signals obtained from the first light receiving element 7 and the second light receiving element 8 are sent to the CPU 13 via the A / D converter 12, respectively. Here, assuming that the angle between the light 10 emitted from the projector 3 and the reference axis 16 in the vehicle width direction of the traveling vehicle (hereinafter, referred to as a measurement attitude angle) is θp, the measurement attitude angle θp is

It is obtained by the following equation. Here, a is the distance from the left end of the first light receiving element 7 to the light receiving position, and b is the second light receiving element 8
Is the distance from the lower end to the light receiving position, and c is the offset distance of the light receiving element 8.

(Equation 1)

When the measured attitude angle θp is obtained, the current CP
The value of the posture angle θn of the vehicle body obtained by the calculation in U13 is
Substitute the measured attitude angle θp (θp → θn). Therefore, after the attitude angle θn is replaced with the measured attitude angle θp, the attitude angle displacement Δθs obtained from the traveling distance detected by the encoder 11 is added to or subtracted from the measured attitude angle θp.

Incidentally, the attitude angle detector 4 is not limited to the one shown in the present embodiment. As shown in FIG. 5, when the light emitted from the projector 3 is other than the beam light, , Each split light from the beam splitter 5 to the lens 1
The first light-receiving element 7 and the second light-receiving element 8 can be made incident via the light-receiving elements 7 and 18. Also in this case, the lens 18 on one side and the second light receiving element 8 are respectively set to the offset distance c.
May be provided and arranged. Further, in the present embodiment, an example in which the light 10 is emitted by the light projector 3 from one of the traveling areas 1 has been described. However, the present invention is not limited to this, and the light projectors 3 are installed on both sides of the traveling area 1, respectively. It is of course possible to do so.

[0020]

According to the present invention, the attitude angle can be corrected each time the traveling vehicle passes the light of the floodlight without providing a correction means such as a reflector or a mark on the floor surface. It is possible to improve the running accuracy because the operation cannot be performed for a long time.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram of the present invention.

FIG. 2 shows a block diagram of the present invention.

FIG. 3 is a conceptual diagram for explaining the principle of the attitude angle detector.

FIG. 4 is a control flowchart of the embodiment of the present invention.

FIG. 5 is a conceptual diagram showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running area 2 Unmanned traveling vehicle 3 Floodlight 4 Attitude angle detector 5 Beam splitter 7 First light receiving element 8 Second light receiving element

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G05D 1/02

Claims (1)

(57) [Claims] 1. An unmanned vehicle that autonomously travels in a predetermined area
Light coming from outside the area to the area
Or at least a projector that emits laser light from the side
In addition to providing one or more,
The first light receiving element and the first light receiving element receive light in different directions.
A second light receiving element, which emits light from the projector
Divides the laser beam with a beam splitter,
The first light receiving element receives the other light, and the other light is received by the second light receiving element.
And one attitude angle detector that detects the attitude angle of the vehicle body is provided.
And the attitude angle determined by the one attitude angle detector.
Unmanned running characterized by correcting the attitude angle of the vehicle body
Car attitude angle correction method .