阅读说明：本技术 测距方法和装置 (Distance measuring method and device ) 是由 赵敏 孟羽 许波 李德胜 郑隽一 张育铭 于 2020-06-12 设计创作，主要内容包括：本发明提供一种测距方法和装置,所述方法包括：通过接收端的接收器接收发射端的发射器同时发射的第一探测波和第二探测波,其中,第一探测波与第二探测波具有不同的传播速度；确定第一探测波到达接收器的时间；将接收器接收到的第二探测波转换为方波,并根据方波的脉冲宽度对第二探测波进行识别,以确定第二探测波实际到达接收器的时间；根据第一探测波的传播速度、第二探测波的传播速度、第一探测波到达接收器的时间和第二探测波实际到达接收器的时间计算发射端与接收端之间的距离。本发明能够大大提高测距精度,并且实现简单,设备的安装、操作也比较方便。(The invention provides a distance measuring method and a distance measuring device, wherein the method comprises the following steps: receiving a first probe wave and a second probe wave simultaneously transmitted by a transmitter of a transmitting end through a receiver of a receiving end, wherein the first probe wave and the second probe wave have different propagation speeds; determining a time of arrival of the first probe wave at the receiver; converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave so as to determine the actual time of the second detection wave reaching the receiver; and calculating the distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time of the first probe wave reaching the receiver and the time of the second probe wave actually reaching the receiver. The invention can greatly improve the distance measuring precision, and has simple realization and more convenient installation and operation of equipment.)

1. A method of ranging, comprising:

receiving a first probe wave and a second probe wave simultaneously transmitted by a transmitter of a transmitting end through a receiver of a receiving end, wherein the first probe wave and the second probe wave have different propagation speeds;

determining a time of arrival of the first probe wave at the receiver;

converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave so as to determine the actual time of the second detection wave reaching the receiver;

and calculating the distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time of the first probe wave reaching the receiver and the time of the second probe wave actually reaching the receiver.

2. The ranging method according to claim 1, wherein the first probe wave is a radio wave and the second probe wave is an ultrasonic wave.

3. The ranging method according to claim 2, wherein the transmitter integrates a radio transmitter and an ultrasonic transmitter, and the receiver integrates a radio receiver and an ultrasonic receiver.

4. The range finding method according to claim 3, wherein identifying the second probe wave according to the pulse width of the square wave to determine the actual arrival time of the second probe wave at the receiver comprises:

calculating the current pulse width of the square wave according to the rising edge and the falling edge of the square wave;

comparing the current pulse width with a preset pulse width in real time;

and when the error between the current pulse width and the preset pulse width is within a preset error range, taking the rising edge moment corresponding to the current pulse width as the time when the second detection wave actually reaches the receiver.

5. The method of claim 4, wherein the distance between the transmitting end and the receiving end is calculated according to the following formula:

wherein L is a distance between the transmitting end and the receiving end, v1 is a propagation velocity of the first probe wave, v2 is a propagation velocity of the second probe wave, t1 is a time when the first probe wave reaches the receiver, and t2 is a time when the second probe wave actually reaches the receiver.

6. A ranging apparatus, comprising:

the transmitter is arranged at a transmitting end and is used for simultaneously transmitting a first probe wave and a second probe wave, wherein the first probe wave and the second probe wave have different propagation speeds;

the receiver is arranged at a receiving end and is used for receiving the first sounding wave and the second sounding wave;

the time determining module is used for determining the time of the first detection wave reaching the receiver, converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave so as to determine the actual time of the second detection wave reaching the receiver;

a distance calculation module, configured to calculate a distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time when the first probe wave reaches the receiver, and the time when the second probe wave actually reaches the receiver.

7. The ranging apparatus according to claim 6, wherein the first probe wave is a radio wave and the second probe wave is an ultrasonic wave.

8. A ranging device as claimed in claim 7 characterized in that the transmitter integrates a radio transmitter and an ultrasonic transmitter and the receiver integrates a radio receiver and an ultrasonic receiver.

9. The ranging apparatus as claimed in claim 8, wherein the time determination module comprises:

the waveform conversion unit is used for converting the second detection wave received by the receiver into a square wave;

the pulse width calculation unit is used for calculating the current pulse width of the square wave according to the rising edge and the falling edge of the square wave;

and the pulse width comparison unit is used for comparing the current pulse width with a preset pulse width in real time, and when the error between the current pulse width and the preset pulse width is within a preset error range, taking the rising edge moment corresponding to the current pulse width as the time when the second detection wave actually reaches the receiver.

10. The range finder device of claim 9, wherein the distance calculation module calculates the distance between the transmitting end and the receiving end according to the following formula:

wherein L is a distance between the transmitting end and the receiving end, v1 is a propagation velocity of the first probe wave, v2 is a propagation velocity of the second probe wave, t1 is a time when the first probe wave reaches the receiver, and t2 is a time when the second probe wave actually reaches the receiver.

Technical Field

The invention relates to the technical field of distance detection, in particular to a distance measuring method and a distance measuring device.

Background

In most distance detection schemes at present, the ultrasonic technology is widely applied, and an ultrasonic ranging system mainly adopts a reflection type ranging method and determines a physical position through methods such as multilateral positioning and the like. The system consists of a main distance meter and a plurality of receivers, and during positioning, the same-frequency signals are transmitted to the receivers, the receivers reflect and transmit the signals to the main distance meter after receiving the signals, and the distance is calculated according to the time difference between echo waves and transmitted waves. However, due to the physical characteristics of the ultrasonic vibration sheet, the ultrasonic vibration sheet can interfere with the ultrasonic waves reflected by the target along with the occurrence of aftershocks, and meanwhile, the ultrasonic vibration sheet is influenced by environmental factors and more uncertain factors such as clutter, and the distance measurement method of the reflection type round-trip time difference enlarges errors and seriously influences the distance measurement effect of the ultrasonic waves.

Some distance detection schemes also use a signal arrival time method, and under the condition that the propagation rate of a signal is known, the distance between the transmitting end and the receiving end is calculated by measuring the time of the signal passing through the transmitting end and the receiving end. The disadvantage of this method is that the small time deviation can cause large distance calculation error due to the large signal transmission rate, so that the transmitter and the receiver need to be connected by wires, and the time is strictly synchronized to measure the signal transit time, which causes the distance measuring equipment to be affected by the wires during the arrangement process, the installation position to be limited, and the practical operation to be inconvenient.

Therefore, it is desirable to provide a ranging scheme that can improve the accuracy of distance detection and implement a simple structure.

Disclosure of Invention

The invention provides a distance measuring method and a distance measuring device for solving the technical problems, which can greatly improve the distance measuring precision, and have the advantages of simple realization and convenient installation and operation of equipment.

The technical scheme adopted by the invention is as follows:

a method of ranging, comprising: receiving a first probe wave and a second probe wave simultaneously transmitted by a transmitter of a transmitting end through a receiver of a receiving end, wherein the first probe wave and the second probe wave have different propagation speeds; determining a time of arrival of the first probe wave at the receiver; converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave so as to determine the actual time of the second detection wave reaching the receiver; and calculating the distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time of the first probe wave reaching the receiver and the time of the second probe wave actually reaching the receiver.

The first probe wave is a radio wave, and the second probe wave is an ultrasonic wave.

The transmitter integrates a radio transmitter and an ultrasonic transmitter, and the receiver integrates a radio receiver and an ultrasonic receiver.

Identifying the second probe wave according to the pulse width of the square wave to determine the actual arrival time of the second probe wave at the receiver, specifically including: calculating the current pulse width of the square wave according to the rising edge and the falling edge of the square wave; comparing the current pulse width with a preset pulse width in real time; and when the error between the current pulse width and the preset pulse width is within a preset error range, taking the rising edge moment corresponding to the current pulse width as the time when the second detection wave actually reaches the receiver.

Calculating the distance between the transmitting end and the receiving end according to the following formula:

wherein L is a distance between the transmitting end and the receiving end, v1 is a propagation velocity of the first probe wave, v2 is a propagation velocity of the second probe wave, t1 is a time when the first probe wave reaches the receiver, and t2 is a time when the second probe wave actually reaches the receiver.

A ranging apparatus comprising: the transmitter is arranged at a transmitting end and is used for simultaneously transmitting a first probe wave and a second probe wave, wherein the first probe wave and the second probe wave have different propagation speeds; the receiver is arranged at a receiving end and is used for receiving the first sounding wave and the second sounding wave; the time determining module is used for determining the time of the first detection wave reaching the receiver, converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave so as to determine the actual time of the second detection wave reaching the receiver; a distance calculation module, configured to calculate a distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time when the first probe wave reaches the receiver, and the time when the second probe wave actually reaches the receiver.

The first probe wave is a radio wave, and the second probe wave is an ultrasonic wave.

The transmitter integrates a radio transmitter and an ultrasonic transmitter, and the receiver integrates a radio receiver and an ultrasonic receiver.

The time determination module includes: the waveform conversion unit is used for converting the second detection wave received by the receiver into a square wave; the pulse width calculation unit is used for calculating the current pulse width of the square wave according to the rising edge and the falling edge of the square wave; and the pulse width comparison unit is used for comparing the current pulse width with a preset pulse width in real time, and when the error between the current pulse width and the preset pulse width is within a preset error range, taking the rising edge moment corresponding to the current pulse width as the time when the second detection wave actually reaches the receiver.

The distance calculation module calculates the distance between the transmitting end and the receiving end according to the following formula:

wherein L is a distance between the transmitting end and the receiving end, v1 is a propagation velocity of the first probe wave, v2 is a propagation velocity of the second probe wave, t1 is a time when the first probe wave reaches the receiver, and t2 is a time when the second probe wave actually reaches the receiver.

The invention has the beneficial effects that:

the invention converts the detection wave received by the receiver into the square wave, identifies the detection wave according to the pulse width of the square wave to determine the actual time of the detection wave reaching the receiver, and calculates the distance between the receiving end and the transmitting end according to the propagation speed and the reaching time of the two detection waves, thereby greatly improving the ranging precision, being simple to realize and being more convenient to install and operate.

Drawings

FIG. 1 is a flow chart of a ranging method according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of ultrasonic zero crossing detection in accordance with one embodiment of the present invention;

FIG. 3 is a schematic diagram of time difference of arrival ranging according to one embodiment of the present invention;

fig. 4 is a block diagram of a distance measuring device according to an embodiment of the invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, the ranging method according to the embodiment of the present invention includes the following steps:

and S1, receiving, by a receiver of the receiving end, a first probe wave and a second probe wave simultaneously transmitted by a transmitter of the transmitting end, wherein the first probe wave and the second probe wave have different propagation speeds.

Preferably, the first probe wave and the second probe wave have a large difference in propagation velocity, e.g. they may be of different orders of magnitude.

In one embodiment of the invention, the first probe wave is a radio wave and the second probe wave is an ultrasonic wave. The transmitter can integrate a radio transmitter and an ultrasonic transmitter, and the receiver can integrate a radio receiver and an ultrasonic receiver, and by integrating the radio transmitter and the ultrasonic transmitter and integrating the radio receiver and the ultrasonic receiver, the transmission and the reception of two kinds of detection waves can be everywhere at the same position point, so that the ranging accuracy can be improved.

S2, determining the time of arrival of the first probe wave at the receiver.

And S3, converting the second detection wave received by the receiver into a square wave, and identifying the second detection wave according to the pulse width of the square wave to determine the actual arrival time of the second detection wave at the receiver.

In an embodiment of the present invention, the second probe wave received by the receiver may be subjected to zero-crossing detection, and the received second probe wave is converted into a square wave by a zero-crossing detection circuit, i.e. as shown in fig. 2, the second probe wave, i.e. the ultrasonic wave, when converted from the positive half cycle to the negative half cycle, may generate a positive high level signal. In the embodiment of the invention, the frequency of the ultrasonic wave is kept constant in the propagation process, so that the ultrasonic wave can generate a square wave with the pulse width kept constant in a fixed sound path. In addition, a filter capacitor and the like can be arranged at the front stage of the zero-crossing detection circuit to assist in filtering clutter signals.

Further, the current pulse width of the square wave can be calculated according to the rising edge and the falling edge of the square wave, that is, the current pulse width is calculated by taking the rising edge moment corresponding to the current pulse as a time starting point and the falling edge moment as a time ending point, then the current pulse width is compared with the preset pulse width in real time, and when the error between the current pulse width and the preset pulse width is within a preset error range, the rising edge moment corresponding to the current pulse width is taken as the time when the second detection wave actually reaches the receiver. In an embodiment of the present invention, the preset pulse width may be an actual pulse width of the ultrasonic wave detected in advance through experiments, and the preset error range is a smaller range, which may limit the calculated pulse width to be substantially the same as the preset pulse width. In other words, after receiving the second detection wave that may contain the interference wave, the actual second detection wave may be identified by the pulse width of the square wave converted by the second detection wave, and the rising edge time of the square wave whose first pulse width matches the actual pulse width will be captured, that is, after identifying the actual second detection wave, the rising edge time of the current square wave will be taken as the time when the second detection wave actually reaches the receiver.

It should be noted that the manner of determining the actual arrival time of the probe wave at the receiver in step S3 is applicable to a probe wave with a constant frequency and easily doped with noise in front of the actual signal. In other embodiments of the present invention, if the first probe wave also meets this characteristic, the time of arrival of the first probe wave at the receiver may also be determined by determining the time of actual arrival of the second probe wave at the receiver in step S3.

And S4, calculating the distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time of the first probe wave reaching the receiver and the time of the second probe wave actually reaching the receiver.

In an embodiment of the present invention, the distance between the transmitting end and the receiving end is determined by a time difference of arrival method, and a ranging scenario performed by using two probe waves with propagation speeds v1 and v2 and arrival times t1 and t2 is shown in fig. 3. The distance between the transmitting end and the receiving end can be calculated according to the following formula:

wherein L is a distance between the transmitting end and the receiving end, v1 is a propagation velocity of the first probe wave, v2 is a propagation velocity of the second probe wave, t1 is a time when the first probe wave reaches the receiver, and t2 is a time when the second probe wave actually reaches the receiver.

In an embodiment of the present invention, since the difference between the propagation speeds of the two probe waves is large, the distance between the transmitting end and the receiving end can be approximated to be related to the difference between the propagation times of the two probe waves, and there is no need to detect the propagation times and perform time synchronization between the transmitting end and the receiving end.

According to the distance measuring method provided by the embodiment of the invention, the detection wave received by the receiver is converted into the square wave, the detection wave is identified according to the pulse width of the square wave, so that the time of the detection wave actually reaching the receiver is determined, and meanwhile, the distance between the receiving end and the transmitting end is calculated according to the propagation speed and the reaching time of the two detection waves, so that the distance measuring precision can be greatly improved, the realization is simple, and the installation and the operation of equipment are more convenient.

Corresponding to the distance measuring method of the above embodiment, the invention further provides a distance measuring device.

As shown in fig. 4, the ranging apparatus according to the embodiment of the present invention includes a transmitter 10, a receiver 20, a time determination module 30, and a distance calculation module 40. The transmitter 10 is arranged at a transmitting end, and the transmitter 10 is used for simultaneously transmitting a first probe wave and a second probe wave, wherein the first probe wave and the second probe wave have different propagation speeds; the receiver 20 is arranged at the receiving end, and the receiver 20 is used for receiving the first probe wave and the second probe wave; the time determination module 30 is configured to determine a time when the first probe wave reaches the receiver 20, and is configured to convert the second probe wave received by the receiver 20 into a square wave, and identify the second probe wave according to a pulse width of the square wave to determine a time when the second probe wave actually reaches the receiver 20; the distance calculating module 30 is configured to calculate a distance between the transmitting end and the receiving end according to the propagation speed of the first probe wave, the propagation speed of the second probe wave, the time when the first probe wave reaches the receiver 20, and the time when the second probe wave actually reaches the receiver 20.

Preferably, the first probe wave and the second probe wave have a large difference in propagation velocity, e.g. they may be of different orders of magnitude.

In one embodiment of the invention, the first probe wave is a radio wave and the second probe wave is an ultrasonic wave. The transmitter 10 may integrate a radio transmitter and an ultrasonic transmitter, and the receiver 20 may integrate a radio receiver and an ultrasonic receiver, and by integrating the radio transmitter and the ultrasonic transmitter and integrating the radio receiver and the ultrasonic receiver, it is possible to make the transmission and reception of both types of probe waves at the same location point, so that it is possible to improve the ranging accuracy.

In one embodiment of the present invention, the time determination module 30 includes a waveform conversion unit, a pulse width calculation unit, and a pulse width comparison unit. The waveform converting unit may convert the second probe wave received by the receiver 20 into a square wave, and specifically, the waveform converting unit may include a zero-crossing detecting circuit, and referring to fig. 2, the second probe wave, i.e., the ultrasonic wave, may generate a positive high-level signal when converted from a positive half cycle to a negative half cycle. In the embodiment of the invention, the frequency of the ultrasonic wave is kept constant in the propagation process, so that the ultrasonic wave can generate a square wave with the pulse width kept constant in a fixed sound path. In addition, a filter capacitor and the like can be arranged at the front stage of the zero-crossing detection circuit to assist in filtering clutter signals. The pulse width calculating unit may calculate a current pulse width of the square wave according to a rising edge and a falling edge of the square wave, that is, a rising edge time corresponding to the current pulse is taken as a time starting point, and a falling edge time is taken as a time ending point, and then the pulse width comparing unit may compare the current pulse width with a preset pulse width in real time, and when an error between the current pulse width and the preset pulse width is within a preset error range, take the rising edge time corresponding to the current pulse width as a time when the second detection wave actually reaches the receiver 20. In an embodiment of the present invention, the preset pulse width may be an actual pulse width of the ultrasonic wave detected in advance through experiments, and the preset error range is a smaller range, which may limit the calculated pulse width to be substantially the same as the preset pulse width. In other words, after the receiver 20 receives the second detection wave, which may include an interference wave, the time determination module 30 may identify the actual second detection wave by the pulse width of the square wave converted from the second detection wave, and capture the rising edge time of the square wave whose first pulse width matches the actual pulse width, that is, after the actual second detection wave is identified, the rising edge time of the current square wave is taken as the time when the second detection wave actually reaches the receiver 20.

It should be noted that the above-mentioned manner of determining the time when the probe wave actually reaches the receiver 20 by the time determination module 30 is applicable to a probe wave with a constant frequency and easily doped with noise in front of an actual signal. In other embodiments of the invention, the time of arrival of the first probe wave at the receiver 20 may also be determined in the manner described above for determining the time of actual arrival of the second probe wave at the receiver 20, if the first probe wave also meets this characteristic.

In an embodiment of the present invention, the distance between the transmitting end and the receiving end is determined by a time difference of arrival method, and a ranging scenario performed by using two probe waves with propagation speeds v1 and v2 and arrival times t1 and t2 is shown in fig. 3. The distance calculating module 40 may calculate the distance between the transmitting end and the receiving end according to the following formula:

where L is the distance between the transmitting end and the receiving end, v1 is the propagation velocity of the first probe wave, v2 is the propagation velocity of the second probe wave, t1 is the time when the first probe wave reaches the receiver 20, and t2 is the time when the second probe wave actually reaches the receiver 20.

In an embodiment of the present invention, since the difference between the propagation speeds of the two probe waves is large, the distance between the transmitting end and the receiving end can be approximated to be related to the difference between the propagation times of the two probe waves, and there is no need to detect the propagation times and perform time synchronization between the transmitting end and the receiving end.

According to the distance measuring device provided by the embodiment of the invention, the detection wave received by the receiver is converted into the square wave, the detection wave is identified according to the pulse width of the square wave, so that the time of the detection wave actually reaching the receiver is determined, and meanwhile, the distance between the receiving end and the transmitting end is calculated according to the propagation speed and the reaching time of the two detection waves, so that the distance measuring precision can be greatly improved, the structure is simple, and the installation and the operation are more convenient.

In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. The meaning of "plurality" is two or more unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.