JPH1053174A - Object detecting method and moving device using this method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid danger caused by misjudgment of an operator and simplify operation by using detectors that can compare distance to an object with the specified distance so as to be able to discriminate far or near by binarization, and automatically judging whether stairs is ascending stairs or descending stairs by combining detected results. SOLUTION: Two stair detectors 6 are installed in front of a device. Light from a light emitting element of each stair detector reaches a first step of ascending stairs, and reflected light comes into each light receiving element. The reflected light into the stair detector with the set value set to d1 detects that an object is in closer distance than the set value d1, and output becomes 'NEAR'. The reflected light comes into the stair detector with the set value set to d2 also detects that the object is in closer distance than the set value d2, and output becomes 'NEAR'. The object in front of the moving device can be detected to be the ascending stairs by the combination of 'NEAR'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for elevating a stair-shaped obstacle, and more particularly, to a method for detecting and controlling the presence or absence of a stair and the ascending and descending of a stair in order to prevent a fall when the stair is moved up and down. It is about.

[0002]

2. Description of the Related Art Conventionally, a large number of moving devices capable of moving up and down stairs have been devised, and some of them have been put to practical use. Generally, an endless track called a crawler is often used as a mechanism for moving up and down stairs or running on uneven terrain. This black
The roller is a belt made of metal or rubber.
Because it has a mechanism to make a revolving motion, it is used not only for stairs but also for traveling on so-called irregular terrain that cannot be run with wheels.

When moving up and down stairs with such a conventional moving device, the entire device is inclined at an angle formed by the stairs.
If the position of the center of gravity of the device at that time is lower than the fulcrum portion in contact with the stairs, the device rotates and falls, which is very dangerous. This state will be described with reference to FIGS. FIG. 6 shows a state where the apparatus is horizontal. FIG.
When moving on a horizontal plane as shown by, the moving device (1)
The center of gravity is almost in the center. However, as shown in FIG.
When climbing the stairs, the moving device (1) is inclined on the stairs. In this case, the force acting in the vertical direction of the center of gravity swings to the lower side of the stairs of the device, so that the device easily falls. In order to solve such a problem, it has been proposed that the center of gravity of the apparatus is largely moved to the upper side of the stairs when going up and down the stairs. An example will be described with reference to FIG.

As shown in FIG. 8, there has been proposed an apparatus designed so that a part of the apparatus can move in a certain direction and the center of gravity moves. The moving mechanism of such a device is simple, but the moving direction of the stairs is fixed. That is, if the position of the center of gravity is moved only in front of the apparatus (in a certain direction), it is necessary to go up the stairs forward and go down the stairs backward. For this reason, it is impossible to move up and down in both directions according to the situation, and when the moving direction of the center of gravity does not match, it is necessary to change the direction by 180 degrees in front of the stairs, and there is a disadvantage that the usability is poor. Another prior art is shown in FIG.

Japanese Unexamined Patent Publication No. Hei 4-306181 proposed a method of moving the center of gravity not in a fixed direction but in front and rear of the apparatus as shown in FIG. In this method, when a part of the apparatus (the upper part in the figure) is moved up the stairs, it is moved in the upper direction of the stairs. In addition, since the moving direction is not fixed, and it can be moved forward or backward according to the situation, there is no need to fix the stairs going up and down direction of the moving device as in the previous example, which improves usability. Was.

However, conventionally, the operator determines the moving direction of the position of the center of gravity in such a mechanism.

[0007]

The use of the conventional moving device was convenient, but when the operator made a mistake in the judgment of the moving direction or entered the stairs without moving the center of gravity, the moving device was overturned. A problem has arisen. That is, in the conventional method in which the operator determines and determines the moving direction of the position of the center of gravity, there is no means for preventing danger of erroneous operation by the operator.

Therefore, the present inventors focused on the control of the position of the center of gravity and conducted research. In a moving device for the purpose of moving up and down stairs as in the present invention, it is necessary to control the position of the center of gravity of the moving device according to rising and falling of the stairs. There was no inexpensive means that could automatically detect lifting and lowering. Therefore, before going up and down the stairs, we decided to study a means to reliably detect the stairs, automatically determine whether the stairs are going up or down, and check whether the center of gravity moving direction is correct. .

In the stair climbing device as in the present invention,
In order to automatically detect the stairs, a method using a distance detector can be considered. The method using this distance detector includes, for example, a set value for detecting the first step of the ascending stairs and a setting value for detecting the first step of the descending stair.
If a set value for detecting the stairs and two set values are provided, a distance shorter than the set value for detecting the first staircase ascending is determined to be a staircase, and the first staircase descending is detected. If the distance is longer than the set value, it can be determined as a descending stair. As described above, by installing one distance detector and comparing the two set values with the measured distance, it is possible to determine the steps of the ascending stairs and the descending stairs. The present inventors proceeded with research based on such a determination method, and then examined a distance detector.

The present inventors first performed a method of detecting a distance based on the amount of light emitted from a light emitting element hitting an object and returning to a light receiving element. However, although this method has the advantage that the detector is inexpensive, the distance detection error due to the reflectance of the object is large, and thus the accuracy of stably detecting one step of the stairs cannot be obtained. Next, using the principle of triangulation, the light emitted from the light emitting element hits the object, and the position where the reflected light returns is used as the light receiving element as a PSD.
And the distance was measured. However, this method is not practical because there is a problem that the circuit configuration becomes complicated, such as noise countermeasures for detecting the steps of the stairs with high accuracy and arithmetic processing for detecting the distance, thereby increasing the device price.

Third, a method of detecting the distance by measuring the time required for light emitted from the light emitting element to hit the object and return to the light receiving element, and a method of detecting the distance by using a phase difference have been employed. However, this method also has the accuracy of detecting the steps of the stairs, but the cost is high because an expensive semiconductor laser is used for the light emitting element or the processing circuit is complicated, which is also not practical. Was.

As described above, there are several methods for the conventional distance detector, but each has a disadvantage. Therefore, conventionally, the operator had to determine the step of the stairs and determine the moving direction of the position of the center of gravity.

[0013]

According to the present invention, a plurality of detectors capable of comparing a distance to an object with a predetermined distance and discriminating the distance from the object are used, and a combination of detection results of the detectors is used. Thereby, an inexpensive measuring means which can automatically determine whether the stairs are the ascending stairs or the descending stairs is provided.

Therefore, the present invention provides a mobile device main body, at least two light emitting devices installed in front of and / or behind the mobile device main body for irradiating an object with light and receiving reflected light from the object. A moving device capable of traveling on flat ground and ascending and descending on stairs having stair detecting means capable of detecting the shape of the ground surface ahead in the traveling direction, having a light receiving element capable of binarizing the distance of the object; Claim 1) "is provided. Secondly, "a moving device main body, at least two light emitting devices installed in front of and / or behind the moving device main body for irradiating the object with light, and receiving the reflected light from the object to receive the object, A stair detecting means capable of detecting the shape of the ground surface in front of the traveling direction, having a light receiving element capable of binarizing the distance of the distance, and a center of gravity of the moving device main body based on information obtained by the stair detecting means. A moving device (claim 2) which has a center of gravity moving means capable of moving in both front and rear directions and is capable of running on level ground and moving up and down on stairs. Third, "a step of irradiating each of the light from the at least two light-emitting elements to the object, and a step of causing each of the reflected lights from the object to be incident on at least two light-receiving elements capable of being binarized and discriminated, A step of binarizing the perspective of each object, a step of comparing the binarized value with a different set value set for each of the light receiving elements, and comparing the respective light receiving elements. A detection method (claim 3), wherein the object is detected by a combination of respective values.

The step-like land in the present invention refers to not only a staircase installed in a building or the like but also a step-like topography.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic side view of a moving apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic front view. The moving device according to this embodiment is a moving device that can be switched to a wheel traveling mechanism when traveling on flat ground or a crawler traveling mechanism when traveling up or down stairs or traveling on uneven terrain. In the figure, 1 is a moving device main body, 2 is a crawler running mechanism for moving up and down stairs, 3 is a frame holding the crawler running mechanism, 4 is an upper mechanism of the main body, which also serves as a loading portion for heavy objects, and has a center of gravity moving mechanism. 5 allows it to move back and forth with respect to the crawler frame. In the present embodiment, two staircase detectors 6 are respectively provided in front of and behind the device.
7 are installed. The amount of movement of the center-of-gravity moving mechanism 5 is set in advance so as not to overturn depending on the inclination angle and weight of the stairs.

The mechanism for moving the center of gravity can be moved by a slide mechanism that can slide back and forth of the moving device. FIG. 3 is a schematic diagram illustrating the mechanism of the stair detectors 6 and 7. Stair detectors installed in front and behind the moving device
It is preferable to use those having the same mechanism.

The staircase detector mainly includes the light emitting element 6
1, light receiving element 62, light emitting lens 63, light receiving lens 64,
It comprises a photoelectric conversion circuit 65 and a comparator 66.
For the light emitting element 61, a light emitting diode or a laser diode can be used. The light receiving element 62 receives the reflected light from the object and performs a binarization determination. As an example of the light receiving element 62, a two-segment photodetector is used.

Hereinafter, a staircase detection method using the staircase detector according to the present invention will be described. First, the light emitting element 61
The light emitted from the object 67 passes through the light-emitting lens 63 and
Are arranged at the center of the light receiving element 62 through the light receiving lens 64 (solid line in the figure). The light receiving element 62 is composed of a photodetector divided into two, and the light receiving output current of one of the detectors (A) is set to I
1, and the other (B) light-receiving output current is I2. These currents are converted into voltages by the photoelectric conversion circuit 65, and the received light output current I1 is changed to the voltage V1 and the received light output current I2 is changed to the voltage V2.
Is converted to In the present embodiment, an example in which a two-segment photodetector is used for the light receiving element has been described. However, the present invention is not limited to this, as long as the detector can perform binarization determination. In the light receiving element 62, the output voltage from each of the divided detectors is equal (V1 = V2) at the distance set in advance.
It is arranged at a position such that

Next, a method of determining whether the position of the object is farther or closer than the set value will be described. When the measured distance is shorter than the set value, that is, when the target is located at the position 68 shown in FIG. 3, the reflected light becomes the optical path indicated by the dotted line in FIG.
At this time, the photodetector of B in FIG. 3 of the two-divided photodetector irradiates more light than the photodetector of A. In this case, the relationship between the light receiving output currents I1 and I2 is I1 <I2. Further, the relationship between the voltages V1 and V2 converted by the photoelectric conversion circuit is V1 <V2. When V1> V2, it is determined that the target is located farther than the set value.

According to such a method, the distance from the mobile device to the object is determined. Next, a method of determining whether a stair is going up or down using this detector will be described with reference to FIG. At least two stair detectors 6 (6a, 6b) are installed in front of the apparatus (see FIG. 2). In the drawing, the beam is emitted perpendicularly to the road surface, but may be emitted obliquely (for example, obliquely forward and downward). At this time, the beams emitted from the two staircase detectors are set so as to irradiate toward the same height step on the road surface.

The stair detectors 6a and 6b have different set values d1 and d2, respectively, and both irradiate the object at the same time. In this embodiment, the staircase detector 6a is
A set value d1 is set in advance between the level ground and the first step of the ascending stairs, and the set value d2 is set in advance in the stair detector 6b between the level ground and the first step of the descending stairs (see FIG. 4). ). Then, as described with reference to FIG. 3, based on the values detected by the respective detectors, those determined to be farther than the set values d1 and d2 (V1> V2) are referred to as “FA”.
R ", those determined to be close (V1 <V2)
Is “NEAR”.

A case where the moving device approaches the stairs while climbing will be described (see FIG. 4). The light (X) from the light emitting elements of the stair detectors 6a and 6b reaches the first step of the ascending stairs, and the reflected light is incident on each light receiving element. As described above, the set value of each detector is different from d1 and d2. Set value is d1
The reflected light incident on the staircase detector 6a, which has been set as, detects that the object is at a distance shorter than the set value d1 (V1 <V2), and the output is "NEAR".

On the other hand, the reflected light incident on the staircase detector 6b whose set value is set to d2 also detects that the object is closer than the set value d2 (V1 <V2). The output is "NEAR". Next, the case where the moving device gets down and approaches the stairs will be described. Stair detectors 6a, 6
The light (Y) from the light emitting element b reaches the first step of the descending stairs, and the reflected light enters each light receiving element. The reflected light that has entered the staircase detector 6a whose set value is set to d1 indicates that the object is at a distance farther than the set value d1 (V1> V2), and therefore the output is “FAR”. The reflected light that has entered the staircase detector 6b also detects that the object is at a distance farther than the set value d2, so the output is “FAR”.
Becomes

When the road surface is substantially flat, the reflected light incident on the staircase detector 6a indicates that the object is at a distance farther than the set value d1 (V1> V2). FAR ". However, the reflected light incident on the staircase detector 6b detects that the object is at a distance shorter than the set value d2 (V1 <V2), and the output is “NEAR”.

Table 1 summarizes the output results of the stair detectors 6a and 6b and the classification of road surface.

[0027]

[Table 1]

As described above, the "FA" of each detector
By the combination of “R” and “NEAR”, it is possible to detect the shape of the ground surface whether the target object in front of the mobile device is ascending, descending, or planar. FIG. 5 is a block diagram illustrating control of the apparatus. The staircase detectors 6a and 6b arranged in front of the apparatus respectively send a signal of "FAR" or "NEAR" to the control device (CPU). Control device (C
PU) can determine whether the stair is an ascending stair or a descending stair according to the determination table of Table 1 based on the respective results sent from the stair detectors 6a and 6b.

Further, the result of the determination can be transmitted to the center of gravity moving mechanism, and the position of the center of gravity can be moved in the direction to be moved. By combining an inexpensive detector that can discriminate binarization of distance and two identical detectors with different set values for a preset distance in this way, it is possible to determine whether it is an ascending stair or a descending stair. It has become possible to judge.

Further, if the detector 7 is provided behind the moving device, the moving device can be moved backward, and the direction of the moving device can be changed without changing the direction by 180 degrees. Further, by changing the set values (d1, d2) of the respective detectors, it is possible to adapt to objects having various steps (for example, stairs). Note that the mobile device of the present invention can be driven by an unmanned person.

[0031]

As described above, according to the present invention, a plurality of inexpensive and simple detectors capable of determining the distance by comparing the distance to the object with a predetermined distance are used. By determining the detection result, it is possible to determine whether the staircase is an ascending staircase or a descending staircase. Since it can be executed without relying on judgment, danger due to erroneous judgment by the operator can be avoided. Further, the operation is simplified, and the burden on the operation of the operator can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic view (side view) of an apparatus showing an embodiment of the present invention.

FIG. 2 is a schematic view (front view) of an apparatus showing one embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a detection principle of a staircase detector according to one embodiment of the present invention.

FIG. 4 is a schematic diagram for explaining the operation of the apparatus having the staircase detector according to one embodiment of the present invention at the time of elevating and lowering.

FIG. 5 is a block diagram illustrating control of an apparatus according to an embodiment of the present invention.

FIG. 6 is a schematic view showing the position of the center of gravity of the apparatus on a flat ground according to an embodiment of the present invention.

FIG. 7 is a schematic diagram showing the position of the center of gravity of the apparatus on the steps of the apparatus according to one embodiment of the present invention.

FIG. 8 is a schematic diagram showing a case where a part of the device on the stairs of the conventional device is moved upward.

FIG. 9 is a schematic view showing a device capable of moving a part of the conventional device back and forth.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Device main body 2 ... Crawler running mechanism 3 ... Crawler frame mechanism 4 ... Device upper mechanism 5 ... Center of gravity moving mechanism 6, 7 ... Stair detector 61 ... Light emitting element 62 ... · Light receiving element 63 · · · light emitting lens 64 · · · light receiving lens 65 · · · photoelectric conversion circuit 66 · · · comparator 67 · · · objects located at a preset distance 68 · · · objects located closer than the preset distance 6a ... one stair detector 6b ... the other stair detector

Claims (3)

[Claims] 1. A moving device main body, at least two light emitting devices installed in front of and / or behind the moving device main body for irradiating an object with light, and receiving light reflected from the object to receive the object. A moving device having a light receiving element capable of discriminating the distance of an object into a binary value and having stair detecting means capable of detecting the shape of the ground surface ahead in the traveling direction, capable of traveling on flat ground and ascending and descending on stairs. 2. A moving apparatus main body, at least two light emitting elements installed in front of and / or behind the moving apparatus main body for irradiating an object with light and receiving reflected light from the object to receive the object. A stair detecting means having a light receiving element capable of binarizing the distance of the object, capable of detecting the shape of the ground surface ahead in the traveling direction, and a center of gravity of the main body of the moving apparatus based on information obtained by the stair detecting means A moving device capable of traveling on level ground and ascending and descending on stairs having a center of gravity moving means capable of moving the vehicle in both front and rear directions. A step of irradiating the object with light from at least two light-emitting elements; and a step of causing respective reflected lights from the object to enter at least two binarized discriminating light-receiving elements. Binarizing the perspective of each of the objects, comparing the binarized value with different set values set for the respective light receiving elements, and comparing the respective light receiving elements. A detection method for detecting the object by a combination of the respective values.