KR100757102B1 - Method and apparatus for mesuring distance in robot cleaner - Google Patents

Abstract

A method and a device for measuring the distance in a robot cleaner are provided to enlarge the distance detecting area by receiving ultrasonic wave signal transmitted from one receiving unit to a plurality of receiving units, thereby reducing the number of a ultrasonic wave generating devices. A device for measuring the distance in a robot cleaner comprises a transmitting unit(410), at least two receiving units(420), and a measuring unit. The transmitting unit transmits ultrasonic wave signal. The receiving units receive the ultrasonic wave signal at a different position reflected from an object transmitted from the transmitting unit. The measuring unit measures the position of the object on the basis of consuming time in which the ultrasonic wave signal transmitted from the transmitting unit is received to each receiving unit.

Description

Method and device for measuring distance in robot cleaner {Method and Apparatus for mesuring distance in Robot Cleaner}

1 illustrates a transmission and reception method using a conventional ultrasonic wave.

2 (a) to 2 (b) show a distance measuring method constructed using the transmission / reception method of FIG.

3 shows a configuration diagram of the distance measuring device of the present invention.

4 (a) to (c) illustrate a transmission and reception method using ultrasonic waves according to the present invention.

5 (a) to 5 (c) illustrate a transmission and reception area of a distance measuring device as a preferred embodiment of the present invention.

6 (a) to 6 (d) illustrate a method of arranging a transmitter and a receiver in a distance measuring apparatus as a preferred embodiment of the present invention.

7 (a) to 7 (b) illustrate a method of measuring a distance and determining a location using ultrasonic signals transmitted and received by a transmitter and a receiver in a distance measuring apparatus.

8 shows a flowchart of a distance measuring method.

9 is a flowchart illustrating a distance measuring method in a robot cleaner according to an exemplary embodiment of the present invention.

10 is a flowchart of a distance measuring method in a robot cleaner according to another preferred embodiment of the present invention.

The present invention relates to the positioning and method of the distance measuring device using ultrasonic waves that can be used in the robot cleaner. More particularly, the present invention relates to a distance measuring apparatus and method for measuring shorter distances by separating and disposing an ultrasonic transmitter and a receiver.

In general, the distance measurement using the ultrasonic wave receives the ultrasonic wave transmitted from the transmitter at the receiver and measures the distance by the speed at which the sound wave proceeds in the air (see FIG. 1).

However, in the related art, an area that can be detected using ultrasonic waves has been limited by receiving only one ultrasonic wave transmitted by one transmitter. When the number of transmitters and receivers is increased to extend the limitation of the area, there is a problem due to interference of ultrasonic signals.

In order to solve the above problems, in the present invention, the transmitter and the receiver are separated and disposed, and the ultrasonic signals transmitted from one transmitter are received by a plurality of receivers, thereby expanding the area in which the distance can be detected using the ultrasonic signals. I would like to. In particular, in the prior art, it is difficult to measure a short distance due to the feature of transmitting and receiving an ultrasonic signal, but in the present invention, a close distance is measured using an ultrasonic signal using a new transmission and reception method of the ultrasonic signal.

In addition, the number of ultrasonic wave generating apparatuses used is reduced by expanding an area that can be detected using the ultrasonic signal.

In addition, based on the ultrasonic signals received by the plurality of receivers, the position as well as the distance of the object will be determined.

As a preferred embodiment of the present invention, the distance measuring device includes a transmitter for transmitting an ultrasonic signal; At least one receiver configured to receive ultrasonic signals transmitted from the transmitter and reflected from an object and returned at different positions, respectively; And a measuring unit measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted from the transmitting unit to be received in each of the receiving units.

Preferably, the transmitter and the at least one receiver of the ranging device are arranged at regular intervals on the surface of a sphere, and the distance from the transmitter to each receiver is constant.

The transmitter and the at least one receiver are also disposed on a surface corresponding to a quarter of a sphere.

In another preferred embodiment of the present invention, the robot cleaner is a transmitter for transmitting an ultrasonic signal in each of the front, left and right rooms; disposed on the left and right to be symmetrical with respect to the front is transmitted from the transmitter to any At least one receiver configured to receive an ultrasonic signal reflected from an object and returned; And a measuring unit measuring the position of the arbitrary object based on the time required for the ultrasonic signals transmitted from the transmitter to be received by the respective receivers.

Preferably, in the robot cleaner, the transmitting unit is disposed between the front and the left side and between the front and the right side, respectively.

In another preferred embodiment of the present invention, the distance measuring method comprises the steps of: (a) transmitting an ultrasonic signal; (b) receiving ultrasonic signals, which are transmitted in step (a) and reflected from an arbitrary object, at different positions; And (c) measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted in the step (a) to be received at each different position of the step (b).

In another preferred embodiment of the present invention, the distance measuring method in the robot cleaner comprises the steps of: (a) transmitting an ultrasonic signal in each of the front, left and right rooms; (b) receiving ultrasonic signals, which are disposed at left and right sides so as to be symmetric with respect to the front, and transmitted at step (a) and reflected from an object and returned at different positions, respectively; And (c) measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted in the step (a) to be received at each of the different positions.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the same elements among the drawings are denoted by the same reference numerals and symbols as much as possible even though they are shown in different drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 illustrates a transmission and reception method using a conventional ultrasonic wave.

Conventional object detection and distance measurement using ultrasonic waves may be performed by using a device in which a transmitter and a receiver are not separated, or as shown in FIG. 1, but a transmitter and a receiver are separated, but implemented in a pair to detect distance and distance to an object. It is common to do

In this case, a reliable measurement value may be obtained only when the distance from the transmitter 110 to the object 130 and the distance from the object 130 to the receiver 120 are at least about 200 mm.

2 (a) to 2 (b) illustrate a distance measuring method configured on a surface of a robot cleaner using the transmission / reception method of FIG. 1.

As illustrated in FIG. 2A, the distance is determined through a method in which the transmitter 210 and the receiver 220 of FIG. 1 are implemented in pairs. That is, when the transmitting ultrasound is transmitted in A, the receiving part of the other ultrasound becomes OFF and the data is valid when the value is recognized only by the receiving part A sensor of the A sensor. However, according to the arrangement of the transceiver, a problem arises in that the range to be measured using ultrasonic waves is limited to a limited portion.

In order to overcome the limitation of such an area, as illustrated in FIG. 2B, the transmitter and the receiver may be disposed in detail to extend the object detection area by ultrasonic waves. However, in this case, the ultrasonic wave transmitted may be detected by another receiver and an error may occur. In order to solve this problem, a method of sensing a distance by using a transmission / reception sensor of ultrasonic waves at a distance where interference does not occur has been proposed, but a problem arises in that the detection of an object does not match in real time.

That is, when the surrounding area is detected in the form of A-> B-> C-> D-> E-> F in the clockwise direction as shown by using the ultrasonic signal, the reception of the ultrasonic signal by A-> B At the time of attempting, a time occurs when the ultrasonic wave transmitted from A is not detected by the receiving unit of B. In addition, the receiving unit of B may incorrectly recognize that an object is detected when the residual ultrasound is detected. Similarly, there is a problem that a temporal error may occur while detecting an ultrasonic signal from A-> B-> C-> D-> E-> F. In order to solve this problem, in the present invention, a method for transmitting and receiving an ultrasonic signal and a layout of a transmitter and a receiver are as follows.

3 shows a configuration diagram of the distance measuring device of the present invention.

The distance measuring device 300 includes a transmitter 310, a receiver 320, and a measurer 330. The transmitter 310 transmits an ultrasonic signal, and the receiver 320 receives an ultrasonic signal transmitted from the transmitter 310 and reflected from an object. In this case, at least one receiver 320 may receive ultrasonic signals transmitted from one transmitter 310 at different positions (see FIG. 4).

Transmitter 310 and at least one receiver 320 are disposed along a circle of arcs or at regular intervals on the surface of a sphere, and the distance from the transmitter to each receiver is constant.

The measurement unit 330 measures the position of any object based on the time required for the ultrasound signals transmitted from the transmitter 310 to be received by the receivers 320 disposed at different positions.

4 (a) to (c) illustrate a transmission and reception method using ultrasonic waves according to the present invention.

4 (a) illustrates an example of receiving two ultrasound signals 411 transmitted from one transmitter 410 by two receivers 420 and 430. If a wall or an object exists in front of the transmitter 410 and the receivers 420 and 430, the trace of the ultrasonic waves reflected by the wall after the transmission of the ultrasonic waves for transmission is received on the left receiver 420 and the right receiver 430. It is different. Therefore, by comparing the values of the left and right ultrasonic receivers 420 and 430 after transmitting the ultrasonic signal from the transmitter 410, the distance of the wall is measured and the position is clearly distinguished.

4 (b) and 4 (c) show regions detected using ultrasonic signals according to the arrangement of the transmitter and receiver.

4 (b) shows an area that can be detected using an ultrasonic signal according to the arrangement of the transmitter and the receiver of the present invention. Compared with FIG. 2A, it can be seen that the sensing region of the ultrasonic signal is extended through an arrangement structure in which the transmitter and the receiver are separated and the ultrasonic signals transmitted from one transmitter are received by the plurality of receivers.

FIG. 4 (c) shows that when the intensity of the ultrasonic signal transmitted from the transmitter is increased, the detection area of the ultrasonic signal is further extended compared to FIG. 4 (b) without the addition of the transmitter and the receiver.

5 (a) to 5 (c) illustrate a transmission and reception area of a distance measuring device as a preferred embodiment of the present invention.

5 (a) and 5 (b) are examples of implementing the distance measuring method in the robot cleaner, and illustrate a distance measuring area in the robot cleaner.

In the robot cleaner, sensing the full range in a circular shape as shown in FIGS. 2 (a) and 2 (b) reduces efficiency in the robot cleaner which performs the basic operation of moving forward, so that only the front part of the bumper structure type is reduced. The ultrasonic measuring method is applied.

The robot cleaner is disposed on the left and right sides so as to be symmetric with respect to the front parts 510, 520, 530, and front parts 510, which transmit ultrasonic signals from the front, left, and right sides, respectively. At least one receiving unit 520, 530 and the receiving unit 520, 530 for receiving an ultrasonic signal reflected back from any object and the time required to receive the ultrasonic signal transmitted from each of the receiving unit It includes a measuring unit for measuring the position of the arbitrary object on the basis.

When an ultrasonic signal is transmitted from the transmitting unit 510 disposed in the forward direction of the robot cleaner, the receiving unit 540 in the 1:30 direction and the receiving unit 550 in the 10:30 direction receive the ultrasonic signal (FIG. 5 (b)).

Similarly, when the transmitting unit 530 disposed at the right side of the 9 o'clock direction and the transmitting unit 520 disposed at the left side of the 3 o'clock direction transmits an ultrasonic signal, the receiving unit 540 at 10:30 and 10:30 The receiving unit 550 in the minute direction receives the ultrasonic signal (FIG. 5B).

FIG. 5C illustrates one form of an ultrasonic transmitter and a receiver mounted in the form of a circular bumper in front of the robot cleaner.

It should be noted that the robot cleaners shown in FIGS. 5A to 5C are only exemplary embodiments of the present invention, but are not limited thereto.

6 (a) to 6 (c) illustrate a method of arranging a transmitter and a receiver in a distance measuring apparatus as one preferred embodiment of the present invention.

The transmitter 600 and the receivers 611 and 612 are arranged to be symmetrical with respect to the transmitter 600. That is, the receiver is arranged such that the angle 610 between the transmitter 600 and the first receiver 611 and the angle 620 between the transmitter 600 and the second receiver 612 are the same.

In addition, as shown in Figure 6 (b), it is possible to detect the object from a point about 10mm away from the outside of the distance measuring device by placing the transmitter and receiver using the characteristics of the ultrasonic signal.

That is, a value obtained by dividing the sum of the distance 'a' 630 from the receiver to the object and the distance 'b' 640 from the object to the transmitter based on a point about 10 mm away from the outside of the distance measuring device or the robot cleaner. By arranging the transmitter and receiver to be 200 mm or more (a + b / 2? 200 mm), it is possible to detect from the 10 mm region using the ultrasonic signal.

FIG. 6 (c) illustrates a process of sensing an object by implementing a method of arranging and transmitting and receiving a transmitter and a receiver according to the present invention in the form of a bumper structure of a robot cleaner.

Figure 6 (d) shows an embodiment of a method for arranging a transceiver according to the present invention in a robot cleaner.

The transmitter 650 was disposed in the forward direction of the robot cleaner, and the receivers 660 and 661 were disposed at the surface positions of 35 degrees on the left and right sides with respect to the transmitter disposed in the front. Then, transmitters 670 and 671 were arranged at positions 33 degrees from the outer surface of each receiver.

7 (a) to 7 (b) illustrate a method of measuring a distance and determining a location using ultrasonic signals transmitted and received by a transmitter and a receiver in a distance measuring apparatus.

7 (a) and 7 (b) illustrate ultrasonic signals transmitted and received by the transmitter and receiver arranged as shown in FIGS. 6 (a) and 6 (c) and a method of determining a location using the ultrasonic signals.

When the transmitting unit transmits an ultrasonic signal (710), the receiving unit simultaneously detects an ultrasonic signal due to noise generated during transmission for a predetermined time after transmitting the ultrasonic signal from the transmitting unit (720). The receiver disregards the ultrasonic signal value input for a predetermined time after the transmitter transmits the ultrasonic signal. Thereafter, based on the incoming ultrasonic signal 721, the time required for the ultrasonic wave transmitted from the transmitter to be received at the receiver is calculated (730) and the distance to the object is converted based on this.

FIG. 7 (b) shows the time required when the ultrasonic signals transmitted from one transmitter are received by the two receivers. By using the difference in the time required by the two receivers, it is possible to determine the position beyond the distance of the object.

That is, referring to FIG. 4A, the distance from the transmitter 410 to the first receiver 420 corresponds to A + B, and the distance from the transmitter 410 to the second receiver 430 is A + B. Corresponds to '. In this case, when the distance to the first receiver 420 is measured to be shorter than the distance to the second receiver 430, it means that the time for returning the reflected wave when the ultrasonic wave proceeds at a constant speed is shorter.

Therefore, since the first receiver 740 illustrated in FIG. 7B shows a shorter time graph than the second receiver 750, it may be determined that an object is located closer to the first receiver.

8 shows a flowchart of a distance measuring method.

After the transmission of the ultrasonic wave from the transmitter, if the ultrasonic signals are received from a plurality of receivers arranged in close proximity to the transmitter, the required time received by the receiver is collected to determine the distance and location.

That is, the distance measuring method transmits an ultrasonic signal, and based on the time required for receiving the ultrasonic signal at the different positions after receiving the ultrasonic signals reflected from the arbitrary objects and returning the ultrasonic signals at the different positions. It consists of measuring the position of any object.

However, a receiver disposed at a position where a plurality of receivers cannot receive an ultrasonic signal transmitted from a transmitter is not considered in measuring the position and distance of an object. The receiver disposed at a position not receiving the ultrasonic signal may be used in determining that an object does not exist in the position.

9 is a flowchart illustrating a distance measuring method in a robot cleaner according to an exemplary embodiment of the present invention.

Distance measurement in a robot cleaner is performed as follows. Ultrasonic signals are sent from the front, left and right sides, respectively. Ultrasonic signals transmitted from the reception units disposed on the left and right sides to be symmetric with respect to the front and reflected from an arbitrary object are received at different positions, respectively. The position and distance of any object is then measured based on the time it takes for the transmitted ultrasound signal to be received at each of these different locations.

As a more specific embodiment, an example in which an ultrasonic signal is generated by a front transmitter is as follows.

The front transmitter transmits the ultrasonic signal at about 38 KHz and 210 μsec (S910). Subsequently, when receiving a waveform as shown in FIGS. 7A to 7B, the microprocessor inside the robot cleaner counts every 10 μsec intervals from the time of transmitting the ultrasonic wave to the time of receiving the ultrasonic wave at the transmitter (S920). ).

When both the left receiver and the right receiver receive the ultrasonic signal (S950), the distance and the position of the object are determined using the required time counted every 10 μsec intervals and the trajectory of the ultrasonic signal (S960).

FIG. 10 is a flowchart illustrating a method for measuring a distance when an ultrasonic signal is transmitted from a transmitter disposed at left and right sides of a robot cleaner according to another preferred embodiment of the present invention.

Each of the left and right transmitters transmits an ultrasonic signal at about 38 KHz and 210 μsec (S1010 and S1020). Subsequently, when receiving a waveform as shown in FIGS. 7A to 7B, the microprocessor inside the robot cleaner counts every 10 μsec intervals from the time when the transmitter transmits the ultrasonic wave to the time when the receiver receives the signal (S1030). ).

When the ultrasound signal is received by both the left receiver and the right receiver (S1040 and S1050), the distance and the position of the object are determined using the required time counted every 10 μsec intervals and the trajectory of the ultrasound signal (S1060 and S1070).

The invention can also be embodied as computer readable code on a computer readable recording medium. Computer-readable recording media include all kinds of recording devices that store data that can be read by a computer system.

Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, which are also implemented in the form of carrier waves (for example, transmission over the Internet). It also includes. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

The best embodiments have been disclosed in the drawings and specification above. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims.

Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

By separating and disposing the transmitter and the receiver, and receiving the ultrasonic signals transmitted by one transmitter from a plurality of receivers, the area where the distance can be detected using the ultrasonic signals is expanded, and the area that can be detected by the ultrasonic signals The number of ultrasonic wave generating apparatuses used can be reduced by expanding the number.

In addition, the ultrasonic signal sensing region can be changed by the transmitter and receiver according to the present invention, and thus the distance can be measured using the ultrasonic signal even in an area having a short measuring range.

In addition, it is possible to grasp not only the distance but also the position of the object based on the ultrasonic signals received by the plurality of receivers.

Claims (7)

A transmitter for transmitting an ultrasonic signal; At least two receivers each receiving an ultrasonic signal transmitted from the transmitter and reflected from an object at a different position; And And a measuring unit for measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted from the transmitting unit to be received at each of the receiving units. The method of claim 1, And the transmitter and the at least two receivers are arranged at regular intervals on the surface of a sphere, and the distance from the transmitter to each of the receivers is constant. 3. A distance measuring device according to claim 2, wherein said transmitter and said at least two receivers are arranged on a surface of a quarter sphere. A transmitter for transmitting an ultrasonic signal from each of the front, left, and right sides; At least two receivers disposed on left and right sides symmetrically with respect to the front to receive ultrasonic signals transmitted from the transmitter and reflected from an object; And And a measuring unit measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted from the transmitting unit to be received at each of the receiving units. The method of claim 4, wherein the receiving unit And a robot cleaner, wherein the robot cleaner is disposed between the front side and the left side and between the front side and the right side, respectively. (a) transmitting an ultrasonic signal; (b) receiving ultrasonic signals, which are transmitted in step (a) and reflected from an arbitrary object, at different positions; And (c) measuring the position of the arbitrary object based on the time required for the ultrasonic signal transmitted in the step (a) to be received at each different position of the step (b); Distance measuring method. delete

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