JP2745650B2 - Ultrasonic obstacle sensor and autonomous mobile robot equipped with it - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic obstacle sensor mounted on a mobile robot or the like for detecting an obstacle, and an autonomous autonomous sensor that performs cleaning along a wall by mounting the ultrasonic obstacle sensor. It relates to a mobile robot.

2. Description of the Related Art Conventionally, an ultrasonic obstacle sensor for detecting the position of an obstacle such as a wall has a configuration as shown in FIGS. FIG. 8 shows an ultrasonic obstacle sensor having a single structure including the ultrasonic element 1 and a horn 12 surrounding the ultrasonic element 1, and FIG. 9 shows the ultrasonic element 1
Are arranged in a plane. With such a configuration, the position of the obstacle is detected by transmitting the ultrasonic wave to the obstacle and measuring the time until the ultrasonic wave is received. As an autonomous mobile robot incorporating such an ultrasonic obstacle sensor, there is one having a configuration as shown in FIG. This is a configuration in which a plurality of single ultrasonic obstacle sensors each including an ultrasonic element 1 having a horn 12 are arranged on the inner periphery of the main body 5 of the autonomous mobile robot.

Problems to be Solved by the Invention The conventional ultrasonic obstacle sensor having the configuration shown in FIG. 8 has a detection angle of 20 due to the characteristics of the ultrasonic element and the horn.
The angle is about ゜ to 30 °, and in FIG. 9, the detection range can be set arbitrarily, but the detection angle is extremely narrow. Further, the autonomous mobile robot shown in FIG. 10 can detect the position of the wall, but it is not easy to determine whether the posture of the main body 5 is parallel to the wall, and the robot moves along the wall. That was difficult.

Therefore, the first object of the present invention is to provide an ultrasonic obstacle sensor having a wide detection angle and a wide detection range,
It is a second object of the present invention to provide an autonomous mobile robot that can easily move along a wall by mounting the ultrasonic obstacle sensor.

Means for Solving the Problems The first means for achieving the first object is as follows. That is, three sets of ultrasonic distance measuring means including an ultrasonic element and an ultrasonic distance measuring circuit, and three planes for holding these ultrasonic elements in the front direction and inwardly 45 ° symmetrically with respect to the front direction. A mounting member composed of a baffle plate,
An ultrasonic obstacle sensor having an obstacle discriminating means for judging the presence or absence of an obstacle from the output of the ultrasonic distance measuring means is provided.

The second means for achieving the second object is as follows. That is, a main body, a driving and steering means for moving the main body, a driving wheel serving as a steering wheel, an auxiliary wheel, a battery for supplying power to the whole, The element is 45
An ultrasonic obstacle sensor according to claim 1, which is installed in the ゜ direction, and a moving direction determining means for determining a moving direction based on information from the two ultrasonic obstacle sensors. It is an autonomous mobile robot.

According to the first means, it is possible to detect an obstacle formed by the three sets of ultrasonic distance measuring means and the mounting member within an angle formed by the mounting member, that is, a range of 90 °.

The operation of the second means is as follows. That is, for example, when moving along the wall surface on the left side of the main body, if the ultrasonic element facing the wall side detects the wall surface, the body is turned to the right, if not detected, the body is turned to the left, so that the posture of the main body is The moving direction determining means operates and controls the driving and steering means. When a new wall is detected by the ultrasonic element facing forward, the drive wheel is temporarily stopped and then the drive wheel is moved relative to the main body.
Turn 90 ° to the right and rotate it until the left ultrasonic obstacle sensor stops detecting anything. If the ultrasonic obstacle sensor on the left stops where nothing is detected,
The body is parallel to this new wall. From here the movement along the wall can be started again.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing one embodiment of the first means, and three sets of ultrasonic distance measuring means comprising an ultrasonic element 1 and an ultrasonic distance measuring circuit 2; A mounting member 3 composed of three baffle plates that are held symmetrically with respect to the front direction in an inward 45 ° direction, and obstacle determining means for determining the presence or absence of an obstacle based on the output of the ultrasonic distance measuring means. 4 constitute an ultrasonic obstacle sensor.

Hereinafter, the operation of the ultrasonic obstacle sensor will be described. FIG. 2 is a diagram illustrating the detection operation of the ultrasonic obstacle sensor according to the present embodiment. An obstacle existing in a range of ± L1 (about ± 15 cm in the present embodiment) from the front direction can be detected by the ultrasonic distance measuring means in the front direction. With respect to the two sets of left and right, an obstacle in the range of L1 in the inward direction and L2 in the outward direction (width formed by the perpendicular w1 or w2 drawn from the center of the left or right ultrasonic element 1 and the mounting member 3) can be detected. . This is because in the configuration of the present embodiment, the mounting member functions as a horn. Therefore, it is possible to detect an obstruction within the angle formed by the mounting member, that is, within the range of 90 °.

Next, FIGS. 3 and 4 are sectional views showing an embodiment of the second means, in which a main body 5 and driving and steering means 6 for driving the main body 5, a driving wheel / steering wheel 7, Auxiliary wheel 8
And a battery 9 for supplying power to the whole, and a supersonic unit constituting the first means in which the left and right equal and central ultrasonic elements 10b are installed in the front of the main body at 45 ° to the front direction of the main body. An autonomous mobile robot is composed of two sets of the ultrasonic obstacle sensors 10 and the moving direction determining means 11 for determining the moving direction based on information from the ultrasonic obstacle sensors 10. In this embodiment, the moving direction determining means 11 is constituted by a microcomputer.

Hereinafter, the autonomous mobile robot will be described. Fifth
The figure is a diagram for explaining the movement of the main body 5. For example, assume that the main body 5 starts from the position of P1 and moves along the wall on the left side in the order of P2, P3, and P4. Moving direction determining means
11, when the main body 5 is at the position P1, if the ultrasonic sensor 10a facing the wall detects the wall as shown in FIG. The driving and steering means 6 is controlled so that the main body 5 faces. In other words, by this, it is possible to move in parallel along the wall while detecting the wall existing on the left side between P1 and P2. When P2 is reached, the ultrasonic element facing forward
At 10c, a new wall is detected, and in this case, the moving direction determining means 11
After the main body 5 is temporarily stopped as shown in FIG. 7, the drive and steering means 6 is driven to rotate the main body 90 ° rightward on the spot. At this time, if the left ultrasonic obstacle sensor 10a stops at a point where nothing is detected, the main body is parallel to the new wall. From here you can move again along the wall towards P4.

In the above description of the embodiment, the wall is described as being on the left side of the main body. However, when the wall is on the right side of the main body, the ultrasonic measuring element facing the wall is naturally 10c, and the rotation shown in FIG. The direction is to the left.

Effects of the Invention As described above, according to the first means, it is possible to provide an ultrasonic obstacle sensor capable of detecting an obstacle within a range of 90 ° with a simple configuration. In the second means, the user can easily move along the wall, and can find a posture parallel to the wall by simply rotating the main body on the spot. Therefore, an autonomous mobile robot suitable for the purpose of being along a wall can be easily realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the ultrasonic obstacle sensor of the present invention, FIG. 2 is an explanatory diagram of a detection range of the ultrasonic obstacle sensor, and FIG. 3 is an ultrasonic obstacle sensor of the present invention. FIG. 4 is a side view, FIG. 5 is an explanatory view for explaining a moving direction of the autonomous mobile robot, and FIG. FIG. 7 is an explanatory view at the position P2, and FIGS. 8 and 9 are explanatory views at the position P2.
The figure shows a conventional example of an ultrasonic obstacle sensor,
FIG. 10 is a diagram showing a conventional example of an autonomous mobile robot. DESCRIPTION OF SYMBOLS 1 ... Ultrasonic element, 2 ... Ultrasonic distance measuring circuit, 3 ... Mounting member, 4 ... Obstacle discriminating means, 5 ... Main body, 6 ... Drive and steering means, 7 ... Drive wheel / steering Wheel, 8 ... Auxiliary wheel, 9 ... Battery, 10 ... Ultrasonic contact sensor, 11
... Moving direction determining means.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Osamu Eguchi, Inventor, 1006 Odakadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Haruo Terai 1006, Odori, Kadoma, Kadoma, Osaka Matsushita Electric Industrial Co., Ltd (56) References JP-A-63-131923 (JP, A) JP-A-60-93524 (JP, A)

Claims (2)

(57) [Claims] An ultrasonic distance measuring means comprising an ultrasonic element and an ultrasonic distance measuring circuit, and these ultrasonic elements are held in the front direction and inwardly 45 ° symmetrically with respect to the front direction. An ultrasonic obstacle sensor comprising: a mounting member formed by three baffle plates; and an obstacle discriminating means for judging the presence or absence of an obstacle based on an output of the ultrasonic distance measuring means. 2. A main body, driving and steering means for moving the main body, a driving wheel serving as a steering wheel, an auxiliary wheel, a battery for supplying power to the whole, and a left and right equal and centered front of the main body. 2. The ultrasonic obstacle sensor 2 according to claim 1, wherein the ultrasonic element is disposed at an angle of 45.degree.
An autonomous mobile robot, comprising: a pair of sets; and a moving direction determining means for determining a moving direction based on information from the two sets of ultrasonic obstacle sensors.