JPH11174145A - Ultrasonic range finding sensor and autonomous driving vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic range finding sensor that can accurately recognize presence of target recessed and projected parts or obstacles. SOLUTION: An ultrasonic range finding sensor 10 includes a sensor part 11 for receiving reflected waves of ultrasonic waves from a target by sending the ultrasonic waves to the target, thus measuring distance to the target based on the transmitted and received waves of ultrasonic waves at the sensor part 11. The ultrasonic range finding sensor 10 can slide the sensor part 11 forward and backward (in the direction marked by an arrow AA') in a direction for connecting the sensor part 11 to the target within an ultrasonic wave passage path 13, ultrasonic waves that are transmitted from the sensor part 11 other than those that are directed (a direction marked by an arrow A) toward the target from the sensor part 11 within the ultrasonic wave passage path 13 are absorbed by an absorption member 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic ranging sensor for measuring a distance to an object based on transmission and reception of ultrasonic waves, and an autonomous vehicle using the same.

[0002]

2. Description of the Related Art Autonomous traveling vehicles have been known that can travel autonomously along an object such as a wall while performing work such as waxing. Such an autonomous vehicle is equipped with an ultrasonic ranging sensor, and travels in the work area while recognizing the surrounding environment and the position of the autonomous vehicle body in the designated work area by the ultrasonic distance sensor. I do.

[0003]

However, when such an autonomous vehicle travels in a work area, if an object such as a wall whose distance is to be measured by the ultrasonic distance measuring sensor has irregularities, the autonomous vehicle will not be able to autonomously operate. The traveling vehicle may travel on a route different from the expected travel route. This is because the ultrasonic ranging sensor cannot recognize the unevenness of the object with high resolution due to the directional angle characteristic of the ultrasonic ranging sensor itself. FIG. 11 is a diagram showing the directional angle of such an ultrasonic ranging sensor. The ultrasonic ranging sensor has a wide range of directional angles as shown in FIG.

Further, due to the directional angle characteristic of the ultrasonic ranging sensor itself, dust and cords on the floor surface on which the autonomous vehicle travels are affected, and the ultrasonic ranging sensor erroneously measures the distance. Sometimes. In order to cope with erroneous measurement of the distance of the ultrasonic ranging sensor, an absorbing member that absorbs ultrasonic waves is provided on the upper surface and the lower surface around the ultrasonic ranging sensor, and the directivity angle of the ultrasonic ranging sensor over a wide range is provided. A technique of squeezing vertically has been proposed. However, even if such an ultrasonic ranging sensor that narrows the vertical direction angle is used, an object that is in the traveling direction while the autonomous vehicle is traveling is erroneously detected due to the directional angle characteristic of the horizontal ultrasonic range sensor. The distance may be measured.

The present invention has been made in view of the above, and an object of the present invention is to provide an ultrasonic ranging sensor and an autonomous traveling vehicle capable of accurately recognizing the unevenness of an object or the presence of an obstacle. That is. Another object of the present invention is to provide an ultrasonic ranging sensor that can adjust the width of a directivity angle.

[0006]

According to a first aspect of the present invention, there is provided a transmission / reception unit for transmitting an ultrasonic wave to an object and receiving a reflected wave of the ultrasonic wave from the object. This is an ultrasonic ranging sensor that measures a distance to an object based on transmission and reception of ultrasonic waves in a wave section.

The ultrasonic distance measuring sensor is characterized in that it includes a member enclosing the transmitting / receiving section so as to absorb all ultrasonic waves in the vicinity of the transmitting / receiving section other than the direction from the transmitting / receiving section toward the object.

According to the first aspect of the present invention, all ultrasonic waves other than the direction from the wave transmitting / receiving section toward the object are absorbed near the wave transmitting / receiving section. Thereby, the directional angle of a wide range that the ultrasonic ranging sensor originally has is narrowed, and the unevenness of the target or the presence of an obstacle is accurately recognized.

According to a second aspect of the present invention, there is provided an ultrasonic distance measuring sensor for measuring a distance to an object based on transmission and reception of ultrasonic waves.

The ultrasonic ranging sensor transmits and receives an ultrasonic wave to an object and receives a reflected wave of the ultrasonic wave from the object, and a transmitting and receiving means near the transmitting and receiving means. An absorbing means for wrapping the transmitting and receiving means so as to absorb the ultrasonic waves other than the direction toward the object, and for moving the transmitting and receiving means back and forth in the direction from the transmitting and receiving means toward the object with respect to the absorbing means. Transportation means.

According to the second aspect of the present invention, the ultrasonic wave is transmitted to the object and the ultrasonic wave is transmitted from the object to the object in the vicinity of the wave transmitting and receiving means for receiving the ultrasonic wave from the object. Ultrasonic waves in directions other than the heading direction are absorbed, and the wave transmitting / receiving means is moved back and forth in the direction from the wave transmitting / receiving means toward the object with respect to the absorbing means. Thereby, the width of the directional angle of the ultrasonic ranging sensor is adjusted.

According to a third aspect of the present invention, there is provided an autonomous traveling vehicle which autonomously travels in parallel to a wall based on measuring a distance between the wall and a wall in a traveling direction using ultrasonic waves. is there.

The autonomous traveling vehicle transmits and receives an ultrasonic wave to a wall surface and receives a reflected wave of the ultrasonic wave from the wall surface, and travels from the wave transmitting and receiving unit to the wall surface in the vicinity of the wave transmitting and receiving unit. Absorbing means for wrapping the transmitting and receiving means so as to absorb the ultrasonic waves other than the direction, moving means for moving the transmitting and receiving means back and forth in the direction from the transmitting and receiving means toward the wall surface with respect to the absorbing means, When the condition is satisfied, in the direction from the wave transmitting / receiving means to the wall surface, forward or backward with respect to the absorbing means,
Control means for controlling the moving means to move the wave transmitting / receiving means is included.

According to the third aspect of the present invention, the ultrasonic wave is transmitted to the object, and the ultrasonic wave is transmitted from the wave transmitting / receiving means to the object near the wave transmitting / receiving means for receiving the ultrasonic wave from the object. When the ultrasonic wave in a direction other than the heading direction is absorbed and a predetermined condition is satisfied, the wave transmitting / receiving unit is controlled to move forward or backward with respect to the absorbing unit in a direction from the wave transmitting / receiving unit to the wall surface. Thus, the width of the directional angle of the ultrasonic ranging sensor can be adjusted as needed, and the unevenness of the target or the presence of an obstacle can be accurately recognized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An ultrasonic ranging sensor and an autonomous vehicle according to embodiments of the present invention will be described below with reference to the drawings.

First, an ultrasonic distance measuring sensor according to an embodiment of the present invention will be described. FIG. 1 and FIG. 2 are diagrams for explaining the configuration of an ultrasonic distance measuring sensor 10 according to one embodiment of the present invention. FIG. 1 is a perspective view showing the configuration of the ultrasonic ranging sensor 10, and FIG. 2 is a sectional view showing the configuration of the ultrasonic ranging sensor 10. As shown in FIG.

The ultrasonic distance measuring sensor 10 includes a sensor unit 11 for transmitting and receiving an ultrasonic wave, and the sensor unit 11 being moved back and forth in the direction connecting the sensor unit 11 and the object to be measured (arrow A).
(A ′ direction) The ultrasonic passage 12 which holds the sensor unit 11 while being slidable and forms a passage through which ultrasonic waves propagate.
And an absorbing member 13 provided on a side surface of the ultrasonic wave passage 12 to absorb all ultrasonic waves other than the direction from the sensor unit 11 toward the object to be measured (the direction of arrow A). Here, it is assumed that the sensor unit 11 can be slid in the front-rear direction (the direction of arrow AA ') by a motor (not shown) or the like.

Here, the radius of the sensor section 11 is set to 2
cm, the oscillation frequency is 40 kHz, and the ultrasonic passage 12
For the dimensions of, the height and width are 4 cm, and the total length is 10 cm. Regarding the range in which the sensor unit 11 slides in the front-rear direction, the position where the sensor unit 11 is located at the deepest part of the ultrasonic passage 12 is set as the rearmost position of the sensor unit 11,
The position where 1 is 8 cm from the innermost part of the ultrasonic passage 12 is defined as the foremost position of the sensor unit 11.

Next, the directivity of the ultrasonic wave transmitted from the ultrasonic distance measuring sensor 10 will be described with reference to FIGS. Here, arrows B and C indicate the ultrasonic distance measuring sensor 1.
It has the largest spread from the opening of the ultrasonic passage 12 among the ultrasonic waves transmitted from 0 (has directivity on the wide-angle side)
Showing things.

FIG. 3 is a diagram showing the directivity of ultrasonic waves transmitted from the ultrasonic distance measuring sensor 10 when the sensor section 11 is slid backward.

When the sensor section 11 is slid backward, the progress of the ultrasonic wave is regulated by the absorbing member 13 in the ultrasonic wave passage 12, and the radiation of the ultrasonic wave originally provided in the ultrasonic distance measuring sensor is performed. The wide angle component of the intensity is absorbed. Thereby, ultrasonic waves are transmitted to a spot area that is a narrower range than usual, and the shape of the target object can be recognized.Received ultrasonic waves reflected from the target object, such as dust on the floor surface The influence of irregular reflection of ultrasonic waves from a cord or the like is suppressed.

FIG. 4 is a diagram showing the directivity of ultrasonic waves transmitted from the ultrasonic distance measuring sensor 10 when the sensor section 11 is slid forward.

When the sensor section 11 is slid forward, the influence of the absorbing member 13 in the ultrasonic passage 12 is small, and the ultrasonic ranging sensor 10 has directivity on the wide-angle side and high strength. Ultrasonic waves are transmitted. As a result, the range that can be measured to the target object is widened, and distance measurement can be performed even at a long distance, but the reception of ultrasonic reflected waves from the target object is caused by dust or cords on the floor surface. It is more susceptible to the irregular reflection of ultrasonic waves from such sources.

As described above, the directional angle of the ultrasonic wave to be transmitted can be adjusted by sliding the sensor portion 11 in the ultrasonic wave passage 12 in the front-rear direction.

When the directivity angle of the ultrasonic wave to be transmitted is narrowed, the intensity of the ultrasonic wave transmitted by the absorbing member 13 is reduced, but the ultrasonic wave is transmitted to the spot area. It is possible to recognize the shape of the uneven surface of the object to be transmitted. When the distance to the object is long, the shape of the uneven surface can be accurately recognized by increasing the output of the ultrasonic wave.

When the directional angle of the ultrasonic wave to be transmitted is widened, the ultrasonic wave is transmitted at a wide angle, and the intensity of the ultrasonic wave by the absorbing member 13 is hardly reduced. Also, a large ranging range can be secured.

Next, a first autonomous vehicle using an ultrasonic ranging sensor 10 (see FIG. 1) according to an embodiment of the present invention will be described.

FIG. 5 is a diagram for explaining the arrangement of the ultrasonic ranging sensor 10 in the present autonomous vehicle.

The autonomous vehicle is provided with an ultrasonic ranging sensor 10.
a, 10b (similar to the above-described ultrasonic ranging sensor 10), and the distance to the left or right wall parallel to the traveling direction (the direction of arrow D in the figure) is determined by the ultrasonic ranging sensor 10a, 1
0b while traveling along one of the right and left walls (following). When the autonomous vehicle travels along the wall on the left side with respect to the traveling direction, the ultrasonic ranging sensor 10a measures the distance to the left wall in the direction of arrow E in the drawing, and When the traveling vehicle travels along the wall on the right side with respect to the traveling direction, the ultrasonic ranging sensor 10b measures the distance to the right wall in the direction of arrow F in the figure.

Such ultrasonic distance measuring sensors 10a, 10a
In the autonomous traveling vehicle having b, the ultrasonic distance measurement sensors 10a and 10b are controlled as described below to control the contour traveling.

FIG. 6 is a flow chart for explaining the procedure of processing relating to contour running using the ultrasonic distance measuring sensors 10a and 10b in the first autonomous vehicle. Here, it is assumed that the autonomous vehicle travels along the left wall while the ultrasonic ranging sensor 10a is used to measure the distance to the left wall, but the ultrasonic ranging sensor 10b is used. The same applies to copying along the right wall.

In the process relating to contour running, first, in step 1 (hereinafter, step is abbreviated as S), the ultrasonic ranging sensor 10a is set to the high output mode and the directivity is narrowed (the directivity angle is narrowed). ) Is controlled as follows. In S2, the distance to the left wall is measured, and the distance D1 to the left wall is the reference distance (the distance between the target travel route that the autonomous vehicle should travel when the autonomous vehicle travels parallel to the wall and the wall). Is calculated as Subsequently, in S3, the ultrasonic ranging sensor 10a is set to the power saving mode, and is controlled so as to increase the directivity (increase the directivity angle). In S4, straight running is started to follow the running.

In step S5, the distance to the left wall is measured by the ultrasonic distance measuring sensor 10a, and the distance D is obtained as the distance measuring value D2. The difference D between the distance measuring value D2 and the reference distance D1 is obtained.
A set value d (>) as a reference for determining whether or not to switch the difference D obtained in S5 and the directivity of the ultrasonic ranging sensor 10a.
0) is compared.

If it is determined in S6 that the difference D is equal to or more than -d and equal to or less than d, it is determined that stable copying is being performed, and the driving system is determined in S11 with the reference distance set to D1. Are controlled to perform the scanning traveling control.

If it is determined in step S6 that the difference D is larger than the set value d, in step S7, the ultrasonic distance measuring sensor 10a is set to the high output mode and the directivity is controlled to a narrow angle. Subsequently, in S8, the distance to the left wall is measured and obtained as a distance measurement value D3. In S9, the distance measurement value D3 is compared with the distance measurement value D2. If the distance value D3 is larger than the distance value D2, it is determined that there is a dent, and in S10, D1 is determined in S2.
Is changed to D3, and the process proceeds to the scanning traveling control of S11. If the distance value D3 is equal to or smaller than the distance value D2, it is determined that there is no dent, and S11 is determined.
, The copying traveling control with the reference distance set to D1 is performed.

Further, if it is determined in S6 that the difference D is smaller than the value -d obtained by changing the sign of the set value d, the ultrasonic ranging sensor 10a is set to the high output mode in S13 and the directivity is narrowed. Is controlled. Subsequently, in S14, the distance to the left wall is measured and obtained as a distance measurement value D4.
Then, the distance measurement value D4 is compared with the distance measurement value D2. If the measured distance value D4 is equal to the measured distance value D2, it is determined that an obstacle has been detected, and in S16, the reference distance set in D1 in S2 is changed to D4, and processing is performed to follow the running control in S11. Is transferred. If the measured distance value D4 is larger than the measured distance value D2, it is determined that dust has been detected, and in S11, copying traveling control is performed with the reference distance set to D1.

After the copying traveling control in S11, it is determined in S12 whether or not the set traveling distance has been reached. If the set mileage has been reached (at S12,
(YES), this processing ends, and if the set traveling distance has not been reached (NO in S12), the processing from S5 is repeated.

Here, S5, S6, S7, S8, S9,
Operations associated with a series of processes of S10, S11, S12, or S5, S13, S14, S15, S16, S1
1. The operations associated with the series of processes in S12 are performed at predetermined time intervals. The autonomous traveling vehicle measures the distance five times a second while traveling at 30 cm / s, and the above-mentioned predetermined time is 200 ms after a certain distance measurement is performed until the next distance measurement is performed. A series of operations described above are performed.

S5, S6, S7, S8,
By a series of processing of S9, S10, S11, S12,
The unevenness of the object whose distance is to be measured is correctly detected, and S5,
An obstacle, dust, and the like are correctly detected by a series of processes in S13, S14, S15, S16, S11, and S12.

The operation of the autonomous vehicle based on the above-described processing will now be described with reference to FIGS.

FIG. 7 is a view for explaining the copying operation of the autonomous vehicle when the left wall has a dent. FIG. 7 (a)
FIG. 7B shows the copying operation of the autonomous vehicle accompanied by the distance measurement to the left wall when using the ultrasonic distance measuring sensor 10a having a wide directivity, and FIG. 7B shows the ultrasonic wave having a narrow directivity. This figure shows the copying traveling of the autonomous vehicle accompanied by distance measurement to the concave surface of the left wall when the distance measurement sensor 10a is used. FIG. 7 (a), FIG.
L1 to L5 in (b) indicate the position of the autonomous vehicle traveling along the left wall, and the number added to L with the passage of time is increased.

When the autonomous traveling vehicle starts traveling while measuring the distance to the wall, first, it measures the reference distance D1 for traveling at the position L1. When the traveling starts, the autonomous traveling vehicle measures the distance to the left wall 101 at the position L2, and travels along the left wall 101 so as to maintain the reference distance D1. At the position L3, the reflected wave of the ultrasonic wave from the left wall 101 affects the distance measurement by the ultrasonic distance measuring sensor 10a having a wide directivity angle, and the distance D3 to the concave surface 102 of the left wall as at the position L5 is reduced. The distance D2 is not accurately measured, and a distance D2 as shown in the figure is measured.

Therefore, in the autonomous traveling vehicle, at the position L4, the directivity angle is switched to be narrow, and the output power of the ultrasonic ranging sensor is increased (the processing in S7 of FIG. 6).
The distance to 02 is correctly measured, and the reference distance is changed to D3 (processing in S10 of FIG. 6). At the position L5, the autonomous vehicle moves the concave surface 10 of the left wall so as to maintain the reference distance.
Run along 2.

As described above, when the ultrasonic ranging sensor is used with a wide directivity so that a change in the distance measurement value can be quickly detected, the directivity angle is reduced with the change in the distance measurement value. By switching, the exact distance to the wall is measured,
In addition, autonomous traveling along a wall including a dent is possible by continuing straight ahead.

FIG. 8 is a view for explaining the copying operation of the autonomous vehicle when there is dust between the left and right walls. FIG. 8A shows an ultrasonic distance measuring sensor 10a having a wide directivity.
FIG. 8B shows the distance measurement to the left wall when using the ultrasonic distance measurement sensor 10a with a narrow directivity.

As shown in FIG. 8A, when a distance measurement value closer to the left wall surface 103 is obtained due to the influence of the reflected wave of the ultrasonic wave from the dust 104, the directivity is narrowed. Distance measurement is performed (processing in S13 of FIG. 6).

As shown in FIG. 8B, if the distance is returned to the value before the influence of the dust 104 when the directivity is set to a narrow angle (D4> D2 in S15 of FIG. 6), the wide angle is set. It is determined that it has been affected by the garbage 104 at the time. If the distance measurement value does not change when the directivity is set to the wide angle or the narrow angle (D4 = D2 in S15 of FIG. 6), it is determined that the distance to an obstacle closer to the left wall has been measured.

As described above, when the ultrasonic ranging sensor is used with the directivity being wide-angle, the directivity is switched to a narrow angle in accordance with a change in the distance measurement value. Obstacles and debris are detected, and even if obstacles and debris are present between the object and the object to be measured, autonomous traveling along the wall is possible by continuing straight ahead.

Next, a description will be given of a second autonomous vehicle using an ultrasonic distance measuring sensor 10 according to an embodiment of the present invention. The second autonomous vehicle has an ultrasonic ranging sensor 10 at the same position as the first autonomous vehicle, and periodically changes the directivity of the ultrasonic ranging sensor 10 (see FIG. 1) to a wide angle and a narrow angle. By switching to an angle (for example, switching to narrow, narrow, narrow, narrow, narrow, wide, and narrow at 0.2-second intervals), dust and obstacles on the side of the main body of the autonomous vehicle are detected.

FIG. 9 is a flow chart for explaining the procedure of processing relating to contour running using the ultrasonic ranging sensors 10a and 10b in the second autonomous vehicle. Here, it is assumed that the autonomous vehicle travels along the left wall while the ultrasonic ranging sensor 10a is used to measure the distance to the left wall, but the ultrasonic ranging sensor 10b is used. The same applies to copying along the right wall.

In the processing relating to the contour running, first, in S10
1, the distance traveled by the autonomous vehicle and the ultrasonic ranging sensor 1
A time interval T1 for widening the directivity of 0a is set, the directivity is narrowed, and a reference distance D5 for contouring traveling control is set.
Is determined, and in S102, the vehicle is controlled to travel straight.

Subsequently, in step S103, the distance traveled by the autonomous vehicle is measured, and in step S104, copying is controlled.
In S105, the traveling distance measured in S103 is equal to S101.
It is determined whether or not the value set in the step has been reached. If the traveling distance has reached the set value (Y in S105)
ES) This process ends, and if the traveling distance has not reached the set value (NO in S105), the process proceeds to S106.

In S106, it is determined whether the time interval T1 set in S101 has elapsed. If the time interval T1 has not elapsed (NO in S106), S1
03, and the process proceeds to S107 if the time interval T1 has elapsed (YES in S106).
The directivity of a is widened, the distance is measured in S108, a distance value D6 is obtained, and a difference D = D6-D5 between the distance value D6 and the reference distance D5 is obtained.

Subsequently, in S109, the difference D and a set value d for determining whether there is an obstacle are determined. If the difference D is smaller than the set value d, traveling control at the time of finding an obstacle is performed in S110, the directivity of the ultrasonic ranging sensor 10a is narrowed in S111, and the processing from S103 is repeated. If the difference D is larger than the set value, S110
Is skipped, the directivity of the ultrasonic ranging sensor 10a is narrowed in S111, and the processing from S103 is repeated.

As described above, the processing from S103 to S111 is repeated until the present processing is completed in S105, and while the contour traveling is performed, the width of the directivity of the ultrasonic distance measuring sensor is switched, and Then, an obstacle is detected and the vehicle travels according to the detection.

Next, the operation of the autonomous vehicle based on the above processing will be described with reference to FIG.

FIG. 10 is a diagram for explaining the copying operation of the autonomous vehicle when there is an obstacle on the left wall. FIG.
L1 to L8 indicate the position of the autonomous vehicle traveling along the left wall, and the number given to L is increased with the passage of time.

In this autonomous vehicle, the directivity of the ultrasonic distance measuring sensor 10a is normally set to a narrow angle, the distance is measured to the left wall surface 105 as at the positions L1 to L3, and the reference distance based on the measured distance is used. Drive while keeping D5. When the autonomous traveling vehicle reaches the position L4 after a lapse of a predetermined time, the autonomous traveling vehicle measures the distance to the left wall surface 105 with the directivity of the ultrasonic ranging sensor 10a being wide-angle, and determines a reference based on the measured distance value. Drive while maintaining the distance D5.

At the positions L5 to L7, the directivity of the ultrasonic distance measuring sensor 10a is narrowed again, and the vehicle travels while maintaining the reference distance D5. Further, when the predetermined time has passed again and the autonomous traveling vehicle reaches the position L8, the directivity of the ultrasonic distance measuring sensor 10a is set to a wide angle, and the distance to the obstacle 106 is measured.

As described above, when the vehicle travels while measuring the distance to the wall, the directivity of the ultrasonic ranging sensor is usually set to a narrow angle, and the directivity is periodically changed, for example, once a second. By performing the distance measurement at a wide angle, it is possible to accurately detect an obstacle such as a person, which is difficult to detect if the directivity remains wide.

In the above embodiment, the ultrasonic distance measuring sensor is provided in the autonomous traveling vehicle. However, the ultrasonic distance measuring sensor can be used for a handy distance measuring device used in a construction site or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of an ultrasonic ranging sensor 10 according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of the ultrasonic distance measuring sensor 10.

FIG. 3 is a diagram showing the directivity of ultrasonic waves transmitted from the ultrasonic distance measuring sensor when the sensor unit is slid backward.

FIG. 4 is a diagram showing the directivity of ultrasonic waves transmitted from the ultrasonic distance measuring sensor 10 when the sensor unit 11 is slid forward.

FIG. 5 is a diagram for explaining an arrangement of an ultrasonic ranging sensor 10 in the autonomous traveling vehicle.

FIG. 6 shows an ultrasonic ranging sensor 10 in a first autonomous vehicle.
It is a flowchart for demonstrating the procedure of the process regarding copying running using a and 10b.

FIG. 7 is a diagram for explaining the following traveling of the autonomous traveling vehicle when the left wall has a dent.

FIG. 8 is a diagram for explaining the copying traveling of the autonomous traveling vehicle when there is garbage up to the left wall.

FIG. 9 shows an ultrasonic ranging sensor 10 in a second autonomous vehicle.
It is a flowchart for demonstrating the procedure of the process regarding copying running using a and 10b.

FIG. 10 is a diagram for explaining copying following the autonomous traveling vehicle when there is an obstacle on the left wall.

FIG. 11 is a diagram showing a directional angle of an ultrasonic ranging sensor.

[Explanation of symbols]

 10, 10a, 10b Ultrasonic ranging sensor 11 Sensor section 12 Ultrasonic passage 13 Absorbing member 101, 103, 105 Left wall surface 102 Left wall concave surface 104 Dust 106 Obstacle

Claims (3)

[Claims] A transmitting / receiving unit that transmits an ultrasonic wave to an object and receives a reflected wave of the ultrasonic wave from the object,
An ultrasonic ranging sensor that measures a distance to an object based on transmission and reception of ultrasonic waves in the transmission / reception unit, wherein the object is transmitted from the transmission / reception unit in the vicinity of the transmission / reception unit. An ultrasonic ranging sensor including a member that wraps the transmission / reception unit so as to absorb all ultrasonic waves in directions other than the direction toward the ultrasonic wave. 2. An ultrasonic ranging sensor for measuring a distance to an object based on transmission and reception of ultrasonic waves, wherein the ultrasonic distance sensor transmits an ultrasonic wave to the object, and transmits the ultrasonic wave to the object. A transmitting and receiving means for receiving a reflected wave of the ultrasonic wave, and an absorbing means for wrapping the transmitting and receiving means so as to absorb an ultrasonic wave other than the direction from the transmitting and receiving means toward the object in the vicinity of the transmitting and receiving means. An ultrasonic ranging sensor, comprising: a moving unit for moving the wave transmitting / receiving unit before and after the absorbing unit in a direction from the wave transmitting / receiving unit toward the object. 3. An autonomous vehicle that travels autonomously in parallel to a wall based on measuring a distance between the wall and a wall in a traveling direction using an ultrasonic wave. Transmitting / receiving means for transmitting ultrasonic waves, receiving reflected waves of the ultrasonic waves from the wall surface, and absorbing ultrasonic waves other than the direction from the wave transmitting / receiving means toward the wall surface in the vicinity of the wave transmitting / receiving means. Absorbing means for enclosing the wave transmitting and receiving means, and moving means for moving the wave transmitting and receiving means back and forth with respect to the absorbing means in a direction from the wave transmitting and receiving means to the wall surface, wherein a predetermined condition is satisfied. In this case, an autonomous vehicle including control means for controlling the moving means so as to move the wave transmitting / receiving means forward or backward of the absorbing means in a direction from the wave transmitting / receiving means to the wall surface.