阅读说明：本技术 超声波测距自动增益校准装置、系统及方法 (Automatic gain calibration device, system and method for ultrasonic ranging ) 是由 王元彬 许少强 陈兆先 于 2021-11-03 设计创作，主要内容包括：本发明提供了一种超声波测距自动增益校准装置、系统及方法,包括：用于采集回波信号的超声波接收模块、自调整放大模块、检波模块、回波信号检测模块以及MCU模块；自调整放大模块对回波信号进行增益放大且使增益值连续可调,输出放大后的回波信号；检波模块采集放大后的回波信号,并对放大后的回波信号进行检波处理；回波信号检测模块将检波处理后的信号与基准电平进行比较,输出有效回波信号；MCU模块持续调节自调整放大模块的增益值,直至有效回波信号能持续达到有效回波强度,将自调整放大模块的增益值作为待校准超声波单元在待测距离的校准增益值。本发明能够自动获取待校准超声波单元的校准增益值,具有结构简单的优点。(The invention provides an automatic gain calibration device, a system and a method for ultrasonic ranging, which comprises the following steps: the ultrasonic wave receiving module is used for collecting echo signals, the self-adjusting amplification module, the detection module, the echo signal detection module and the MCU module; the self-adjusting amplification module performs gain amplification on the echo signal, enables the gain value to be continuously adjustable and outputs the amplified echo signal; the detection module collects the amplified echo signals and carries out detection processing on the amplified echo signals; the echo signal detection module compares the signal after the detection processing with a reference level and outputs an effective echo signal; and the MCU module continuously adjusts the gain value of the self-adjusting amplification module until the effective echo signal can continuously reach the effective echo intensity, and the gain value of the self-adjusting amplification module is used as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be calibrated. The ultrasonic unit calibration device can automatically acquire the calibration gain value of the ultrasonic unit to be calibrated, and has the advantage of simple structure.)

1. An ultrasonic ranging automatic gain calibration device, comprising:

the ultrasonic receiving module is used for acquiring echo signals sent by the ultrasonic unit to be calibrated at a distance to be measured;

the self-adjusting amplification module is electrically connected with the ultrasonic receiving module and used for performing gain amplification on the echo signal, enabling the gain value to be continuously adjustable from small to large and outputting the amplified echo signal;

the detection module is electrically connected with the self-adjusting amplification module and is used for collecting the amplified echo signals, detecting the amplified echo signals and outputting detected signals;

the echo signal detection module is electrically connected with the detection module and used for comparing the signal after the detection processing with a reference level and outputting an effective echo signal;

and the MCU module is electrically connected with the detection module and is used for continuously adjusting the gain value of the self-adjusting amplification module until the effective echo signal can continuously reach the effective echo intensity, and the gain value of the self-adjusting amplification module is used as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be calibrated.

2. The apparatus of claim 1, wherein the self-adjusting amplifier module comprises:

the echo signal amplifying unit is electrically connected with the ultrasonic receiving module and used for amplifying the echo signal by a certain gain value;

the gain adjusting unit is electrically connected with the echo signal amplifying unit and is used for adjusting the amplification gain value of the echo signal amplifying unit;

the gain adjusting unit is electrically connected with the MCU module and used for adjusting the amplification gain value of the echo signal amplifying unit according to the instruction of the MCU module.

3. The ultrasonic ranging automatic gain calibration device according to claim 2, wherein the echo signal amplifying unit comprises:

the first operational amplification circuit is electrically connected with the ultrasonic receiving module and is used for carrying out primary amplification on the echo signal;

the second operational amplification circuit is electrically connected with the first operational amplification circuit and is used for carrying out secondary amplification on the echo signal;

the gain adjusting unit is arranged between the first operational amplifying circuit and the second operational amplifying circuit and used for adjusting the amplification factor of the second operational amplifying circuit according to the instruction of the MCU module.

4. The automatic gain calibration device for ultrasonic ranging according to claim 3, wherein the gain adjusting unit comprises: a digital potentiometer;

the control end of the digital potentiometer is electrically connected with the MCU module;

the digital potentiometer is connected in parallel between the first operational amplification circuit and the second operational amplification circuit.

5. The ultrasonic ranging automatic gain calibration device according to claim 3, wherein the echo signal amplifying unit comprises: a fourteenth resistor, a sixteenth resistor, an eighteenth resistor, a nineteenth resistor, a first operational amplifier and a second operational amplifier;

the first operational amplifier is electrically connected with the fourteenth resistor and the eighteenth resistor to form the first operational amplifier circuit;

the second operational amplifier is electrically connected with the sixteenth resistor to form the second operational amplifier circuit;

the nineteenth resistor is arranged between the first operational amplification circuit and the second operational amplification circuit, connected in parallel with the gain adjustment unit, and used for adjusting the amplification factor of the second operational amplification circuit.

6. The ultrasonic ranging automatic gain calibration device according to claim 5, wherein:

the gain of the first operational amplifier circuit is A1= -R14/R18;

the gain of the second operational amplifier circuit is a2= -R16 = (R19 + RU 3)/(R19 RU 3);

wherein RU3 is the resistance of the gain adjustment unit; r14 is the resistance of the fourteenth resistor; r16 is the resistance of the sixteenth resistor; r18 is the resistance of the eighteenth resistor; r19 is the resistance of the nineteenth resistor.

7. The ultrasonic ranging automatic gain calibration device according to claim 1, further comprising: a communication module;

the communication module is electrically connected with the MCU module and is used for sending the calibration gain value of the ultrasonic unit to be calibrated to an external receiving end.

8. An ultrasonic ranging automatic gain calibration system, comprising:

the ultrasonic ranging automatic gain calibration device according to any one of claims 1 to 7;

the connecting piece is used for setting the ultrasonic ranging automatic gain calibration device and the ultrasonic unit to be calibrated;

the reflecting piece is arranged on the sensing side of the ultrasonic unit to be calibrated and can move along the sensing direction of the ultrasonic unit to be calibrated;

and the PC terminal is used for carrying out data interaction with the ultrasonic ranging automatic gain calibration device, and is used for acquiring a calibration gain value sent by the ultrasonic ranging automatic gain calibration device and displaying the calibration gain value on the PC terminal.

9. An ultrasonic ranging automatic gain calibration system as defined in claim 8 wherein:

the ultrasonic unit to be calibrated is arranged in the middle of the connecting piece and used for sending ultrasonic waves to the middle of the reflecting piece;

and the PC end is electrically connected with the ultrasonic unit to be calibrated and used for controlling the start and stop of the ultrasonic unit to be calibrated.

10. An automatic gain calibration method using the ultrasonic ranging automatic gain calibration apparatus according to claim 1, comprising:

acquiring echo signals sent by an ultrasonic unit to be calibrated at a distance to be measured by using an ultrasonic receiving module;

performing gain amplification on the echo signal through a self-adjusting amplification module, enabling the gain value to be continuously adjustable from small to large, and outputting the amplified echo signal;

acquiring the amplified echo signal through a detection module, detecting the amplified echo signal, and outputting a signal after detection;

comparing the signal after the detection processing with a reference level by using an echo signal detection module, and outputting an effective echo signal;

and continuously adjusting the gain value of the self-adjusting amplification module through the MCU module until the effective echo signal can continuously reach the effective echo intensity, and taking the gain value of the self-adjusting amplification module as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be calibrated.

Technical Field

The invention relates to the field of ultrasonic range finder calibration, in particular to an automatic gain calibration device, system and method for ultrasonic range finding.

Background

Ultrasonic detection is a detection means with wide application, wherein the ultrasonic range finder is very prominent to be applied to the aspects of reversing radar of an automobile, a height measuring instrument, vehicle induction of a parking space, obstacle avoidance measurement of a robot and the like. Ultrasonic ranging is a ranging method based on the TOF principle, but due to the attenuation characteristic of ultrasonic waves in air, the sensitivity of a ranging device must be improved to increase the measuring distance, namely the amplification factor of an echo signal of the measuring device must be greatly improved; however, since the echo includes various interference signals in addition to the target echo signal, the increase in the amplification factor may increase the short-range interference signal, which may cause an error in the distance measurement calculation.

Currently, there is a method for calibrating an ultrasonic depth finder using a hydroacoustic technique, comprising: firstly, carrying out N groups of depth measurement experiments on a depth measuring instrument to be measured; comparing the depth measurement result with the scale marks of the scale, calculating errors, and obtaining the corrected value of each depth measurement parameter according to a depth measurement parameter algorithm; then, regulating the DA pressure control of the calibration detection device through a standard interval, such as 1m, and measuring the maximum action distance which can be detected by the depth finder at the moment; finally, shortening the distance between the two transducers, adjusting the DA controlled pressure of the calibration detection device, and measuring the minimum action distance which can be detected by the depth finder; the depth finder in the method uses an ultrasonic sensor, but the method adopts a standard interval to adjust the DA control pressure of a calibration detection device, so as to obtain the maximum distance and the minimum distance which can be detected by the depth finder, namely the ultrasonic sensor; however, this method cannot perform gain calibration of the ultrasonic sensor itself.

Meanwhile, the prior art can also carry out sectional calibration on the ultrasonic distance measuring instrument before leaving the factory, and different echo signal amplification factors are adopted in different distance ranges, for example, a small amplification factor is adopted in a short distance, and a large amplification factor is adopted in a long distance, so that an interference signal and a target signal are effectively balanced, and a group of sectional amplification factor parameters belonging to the module are obtained; the finer the segmentation calibration is done, the more stable the ultrasonic ranging performance is.

It is known that, due to the limitation of the manufacturing process of the ultrasonic probe, even if the conversion efficiency and the sensitivity of the transceiving probes in the same batch are within a large range, in order to ensure the consistency of the measurement performance of the ultrasonic ranging module, each of the transceiving probes must be calibrated and cannot be replaced by the same set of parameters. However, the whole calibration process is very complicated, the labor input workload is huge, the calibration time is long, the efficiency is low, and the factory cost of the device is increased.

In view of this, an automatic gain calibration device for ultrasonic ranging is in urgent need of research and development.

Disclosure of Invention

To overcome the deficiencies of the prior art, the present invention provides an apparatus, a system and a method for calibrating an automatic gain for ultrasonic ranging, which are used to solve at least one of the aforementioned technical problems.

Specifically, the technical scheme is as follows:

an ultrasonic ranging automatic gain calibration device, comprising:

the ultrasonic receiving module is used for acquiring echo signals sent by the ultrasonic unit to be calibrated at a distance to be measured;

the self-adjusting amplification module is electrically connected with the ultrasonic receiving module and used for performing gain amplification on the echo signal, enabling the gain value to be continuously adjustable from small to large and outputting the amplified echo signal;

the detection module is electrically connected with the self-adjusting amplification module and is used for collecting the amplified echo signals, detecting the amplified echo signals and outputting detected signals;

the echo signal detection module is electrically connected with the detection module and used for comparing the signal after the detection processing with a reference level and outputting an effective echo signal;

and the MCU module is electrically connected with the detection module and is used for continuously adjusting the gain value of the self-adjusting amplification module until the effective echo signal can continuously reach the effective echo intensity, and the gain value of the self-adjusting amplification module is used as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be calibrated.

The self-adjusting amplification module comprises:

the echo signal amplifying unit is electrically connected with the ultrasonic receiving module and used for amplifying the echo signal by a certain gain value;

the gain adjusting unit is electrically connected with the echo signal amplifying unit and is used for adjusting the amplification gain value of the echo signal amplifying unit;

the gain adjusting unit is electrically connected with the MCU module and used for adjusting the amplification gain value of the echo signal amplifying unit according to the instruction of the MCU module.

The echo signal amplifying unit includes:

the first operational amplification circuit is electrically connected with the ultrasonic receiving module and is used for carrying out primary amplification on the echo signal;

the second operational amplification circuit is electrically connected with the first operational amplification circuit and is used for carrying out secondary amplification on the echo signal;

the gain adjusting unit is arranged between the first operational amplifying circuit and the second operational amplifying circuit and used for adjusting the amplification factor of the second operational amplifying circuit according to the instruction of the MCU module.

The echo signal amplifying unit includes: a fourteenth resistor, a sixteenth resistor, an eighteenth resistor, a nineteenth resistor, a first operational amplifier and a second operational amplifier;

the first operational amplifier is electrically connected with the fourteenth resistor and the eighteenth resistor to form the first operational amplifier circuit;

the second operational amplifier is electrically connected with the sixteenth resistor to form the second operational amplifier circuit;

the nineteenth resistor is arranged between the first operational amplification circuit and the second operational amplification circuit, connected in parallel with the gain adjustment unit, and used for adjusting the resistance value of the gain adjustment unit so as to change the amplification factor of the second operational amplification circuit.

The gain of the first operational amplifier circuit is A1= -R14/R18;

the gain of the second operational amplifier circuit is a2= -R16 = (R19 + RU 3)/(R19 RU 3);

wherein RU3 is the resistance of the gain adjustment unit; r14 is the resistance of the fourteenth resistor; r16 is the resistance of the sixteenth resistor; r18 is the resistance of the eighteenth resistor; r19 is the resistance of the nineteenth resistor.

The gain adjustment unit includes: a digital potentiometer;

the control end of the digital potentiometer is electrically connected with the MCU module;

the digital potentiometer is connected in parallel between the first operational amplification circuit and the second operational amplification circuit.

The ultrasonic ranging automatic gain calibration device further comprises: a communication module;

the communication module is electrically connected with the MCU module and is used for sending the calibration gain value of the ultrasonic unit to be calibrated to an external receiving end.

An ultrasonic ranging automatic gain calibration system comprising:

the ultrasonic ranging automatic gain calibration device;

the connecting piece is used for setting the ultrasonic ranging automatic gain calibration device and the ultrasonic unit to be calibrated;

the reflecting piece is arranged on the sensing side of the ultrasonic unit to be calibrated and can move along the sensing direction of the ultrasonic unit to be calibrated;

and the PC terminal is used for carrying out data interaction with the ultrasonic ranging automatic gain calibration device, and is used for acquiring a calibration gain value sent by the ultrasonic ranging automatic gain calibration device and displaying the calibration gain value on the PC terminal.

The ultrasonic unit to be calibrated is arranged in the middle of the connecting piece and used for sending ultrasonic waves to the middle of the reflecting piece;

and the PC end is electrically connected with the ultrasonic unit to be calibrated and used for controlling the start and stop of the ultrasonic unit to be calibrated.

An automatic gain calibration method using the ultrasonic ranging automatic gain calibration device comprises the following steps:

acquiring echo signals sent by an ultrasonic unit to be calibrated at a distance to be measured by using an ultrasonic receiving module;

performing gain amplification on the echo signal through a self-adjusting amplification module, enabling the gain value to be continuously adjustable from small to large, and outputting the amplified echo signal;

acquiring the amplified echo signal through a detection module, detecting the amplified echo signal, and outputting a signal after detection;

comparing the signal after the detection processing with a reference level by using an echo signal detection module, and outputting an effective echo signal;

and continuously adjusting the gain value of the self-adjusting amplification module through the MCU module until the effective echo signal can continuously reach the effective echo intensity, and taking the gain value of the self-adjusting amplification module as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be calibrated.

The invention has at least the following beneficial effects:

the device acquires echo signals sent by an ultrasonic unit to be calibrated at a distance to be measured, performs gain amplification on the echo signals, and has an adjustable gain value, acquires the amplified echo signals, and performs detection processing on the amplified echo signals to obtain signals after the detection processing; comparing the signal after the detection processing with a reference level, and outputting an effective echo signal; finally, when the effective echo signals are continuously acquired, recording a gain value of the self-adjusting amplification module as a calibration gain value of the ultrasonic unit to be calibrated at the distance to be measured; the device can automatically adjust the gain of the echo signal, and acquire the calibration gain value of the ultrasonic unit to be calibrated when the gain value is proper, and has the advantages of simple structure and high calibration efficiency.

The system provided by the invention has the advantages that the device is applied, the reflecting piece moves along the induction direction of the ultrasonic unit to be calibrated, the calibration gain values of the ultrasonic unit to be calibrated on different distances are respectively calibrated, the segmented calibration of the ultrasonic unit to be calibrated can be realized through an automatic calibration mechanism, the automatic judgment and the automatic completion are realized, the calibration efficiency is high, the performance consistency is high, the reliability is strong, the production and shipment efficiency can be greatly promoted, and the cost is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a block diagram of an automatic gain calibration device for ultrasonic ranging according to the present invention;

FIG. 2 is a schematic circuit diagram of an ultrasonic receiving module and a self-adjusting amplifying module in the automatic gain calibration apparatus for ultrasonic ranging according to the present invention;

FIG. 3 is a schematic circuit diagram of a detection module of the automatic gain calibration device for ultrasonic ranging according to the present invention;

FIG. 4 is a schematic circuit diagram of an echo signal detection module in the automatic gain calibration apparatus for ultrasonic ranging according to the present invention;

FIG. 5 is a schematic diagram of an automatic gain calibration system for ultrasonic ranging according to the present invention;

FIG. 6 is a flowchart illustrating an automatic gain calibration method for ultrasonic ranging according to the present invention.

100, an ultrasonic receiving module; 200. a self-adjusting amplification module; 300. a detection module; 400. an MCU module; 500. an ultrasonic unit to be calibrated; 600. a communication module; 700. an ultrasonic wave emitting unit; 800. an echo signal detection module; 201. an echo signal amplifying unit; 202. a gain adjustment unit;

wherein, 1, connecting piece; 2. a reflector; 3. a PC terminal;

it is to be understood that: the two "A" ends in FIGS. 2-4 represent interconnecting wires; the two "B" ends also represent interconnecting wires.

Detailed Description

Those skilled in the art will appreciate that the modules in the devices in the implementation scenario may be distributed in the devices in the implementation scenario according to the description of the implementation scenario, or may be located in one or more devices different from the present implementation scenario with corresponding changes. The modules of the implementation scenario may be combined into one module, or may be further split into a plurality of sub-modules.

The noun explains:

effective echo signal: the output of the echo signal detection module 800 generates a level jump, i.e., an effective echo signal;

effective echo intensity: the MCU module 400 performs analog signal intensity acquisition on the echo signal output by the detection module 300 through the ADC, and the mean voltage of the continuous acquisition duration t ≈ 500us (more than 5 acquisitions) for the echo signal from the effective echo signal jump edge is greater than the reference voltage of the comparator in the echo signal detection module 800.

In order to solve the problems of the prior art, the invention discloses the following embodiments:

specific example I:

the invention discloses an automatic gain calibration device for ultrasonic ranging, as shown in figure 1, comprising: the ultrasonic wave detection device comprises an ultrasonic wave receiving module 100, a self-adjusting amplifying module 200, a wave detection module 300, an MCU module 400, a communication module 600, an ultrasonic wave transmitting unit 700 and an echo signal detection module 800, wherein the ultrasonic wave receiving module 100 is used for collecting echo signals sent by an ultrasonic wave unit 500 to be calibrated at a distance to be measured; the self-adjusting amplification module 200 is electrically connected to the ultrasonic receiving module 100, and is configured to perform gain amplification on the echo signal, adjust a gain value, and output the amplified echo signal; the detection module 300 is electrically connected to the self-adjusting amplification module 200, and is configured to collect the amplified echo signal, detect the amplified echo signal, and output a signal after detection; the echo signal detection module 800 is electrically connected to the detection module 300, and configured to compare the signal after the detection processing with a reference level and output an effective echo signal; the MCU module 400 is also electrically connected to the detection module 300, and is configured to continuously adjust the gain value of the self-adjusting amplification module 200 until the effective echo signal can continuously reach the effective echo intensity, and use the gain value of the self-adjusting amplification module 200 as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be measured; the communication module 600 is electrically connected to the MCU module 400, and is configured to send the calibration gain value of the ultrasonic unit 500 to be calibrated to an external receiving end; the ultrasonic wave emitting unit 700 includes an ultrasonic wave emitting circuit for connecting the ultrasonic wave unit 500 to be calibrated for emitting an ultrasonic wave.

The self-adjusting amplification module 200 includes: an echo signal amplifying unit 201 and a gain adjusting unit 202; the echo signal amplifying unit 201 is electrically connected to the ultrasonic receiving module 100, and is configured to amplify the echo signal by a certain gain value; a gain adjusting unit 202 electrically connected to the echo signal amplifying unit 201, for adjusting an amplification gain value of the echo signal amplifying unit 201; the gain adjusting unit 202 is electrically connected to the MCU module 400, and is configured to adjust an amplification gain value of the echo signal amplifying unit 201 according to an instruction of the MCU module 400.

Preferably, as shown in fig. 2 to 4, the echo signal amplifying unit is composed of a two-stage amplifying circuit, and includes: a first operational amplifier circuit and a second operational amplifier circuit; the first operational amplification circuit is electrically connected with the ultrasonic receiving module and is used for carrying out primary amplification on the echo signal; the second operational amplification circuit is electrically connected with the first operational amplification circuit and is used for carrying out secondary amplification on the echo signal; the gain adjusting unit 202 is disposed between the first operational amplifier circuit and the second operational amplifier circuit, and is configured to adjust an amplification factor of the second operational amplifier circuit according to an instruction of the MCU module 400, so as to generate a gain adjusting effect; further, the gain adjustment unit 202 is preferably a digital potentiometer; the control end of the digital potentiometer is electrically connected with the MCU module 400; the digital potentiometer is connected in parallel between the first operational amplifier circuit and the second operational amplifier circuit.

The working principle of the present embodiment is explained with reference to fig. 2 to 4:

the embodiment inputs the echo signal received by the ultrasonic receiving module 100 into the echo signal amplifying unit 201 for amplification; the echo signal amplifying unit 201 and the gain adjusting unit 202 perform a combined action, and the gain of the second operational amplifying circuit in the echo signal amplifying unit 201 is adjusted, so that the gain is adjustable; the echo signal amplifying unit 201 is mainly composed of a fourteenth resistor R14, a sixteenth resistor R16, an eighteenth resistor R18, a nineteenth resistor R19, a first operational amplifier and a second operational amplifier; the first operational amplifier is electrically connected with a fourteenth resistor R14 and an eighteenth resistor R18 to form the first operational amplifier circuit; the second operational amplifier is electrically connected with a sixteenth resistor R16 to form the second operational amplifier circuit; the nineteenth resistor R19 is arranged between the first operational amplification circuit and the second operational amplification circuit and connected with the digital potentiometer U3 in parallel, and is used for adjusting the resistance RU3 of the digital potentiometer U3 so as to change the amplification factor of the second operational amplification circuit; the gain of the first operational amplifier circuit is a1= -R14/R18, and the gain of the second operational amplifier circuit is a2= -R16 = (R19 + RU 3)/(R19 = -RU 3); the amplification factor of the second operational amplification circuit is changed by changing the resistance RU3 of the digital potentiometer U3 connected in parallel with the nineteenth resistor R19, so that a gain adjustment effect is generated. The amplified echo signal is subjected to detection processing by a detection module 300 consisting of a detection diode D1, a twenty-fourth resistor R24, a twenty-fourth capacitor C24 and a twenty-sixth capacitor C26, and then is respectively output to ADC channels of the echo signal detection module 800 and the MCU module 400; the echo signal detection module 800 mainly comprises a comparator U4, a twenty-third resistor R23, a seventeenth resistor R17, a thirteenth resistor R13 and a twenty-fifth resistor R25, and can compare the echo signal with a reference voltage Vref (Vref = +5VR × R25/(R13+ R25)) to generate a level pulse, and input the level pulse to the MCU module 400 to trigger an effective echo intensity detection process; finally, when the effective echo signal can continuously reach the effective echo intensity, taking the gain value of the self-adjusting amplification module 200 as the calibration gain value of the ultrasonic unit to be calibrated at the distance to be measured; the calibration gain value may be transmitted to an external receiver, such as a PC terminal or a portable device terminal, through the communication module 600; the PC end or the portable equipment end is provided with a display device, such as a display or a display screen, so that related information can be visually displayed and is convenient to check.

Specific example II:

the invention also provides an embodiment:

as shown in fig. 5, an ultrasonic ranging automatic gain calibration system includes: the ultrasonic ranging automatic gain calibration device disclosed in embodiment I, and the connecting member 1, the reflecting member 2, and the PC terminal 3 for setting the ultrasonic ranging automatic gain calibration device and the ultrasonic unit 500 to be calibrated; wherein the reflector 2 is arranged on the opposite side of the ultrasonic unit 500 to be calibrated and is movable in the direction of the ultrasonic waves emitted by the ultrasonic unit 500 to be calibrated; the PC terminal 3 performs data interaction with the ultrasonic ranging automatic gain calibration device, and is used for acquiring a calibration gain value sent by the ultrasonic ranging automatic gain calibration device, sending the calibration gain value to the PC terminal 3 through the communication module 600, and displaying the calibration gain value on the PC terminal 3.

Preferably, in order to ensure the detection effect, the connecting piece 1 is preferably a table-type fixed body; the ultrasonic unit 500 to be calibrated is arranged at the center of the connecting piece 1; the reflecting member 2 is preferably a plate-shaped object, and is arranged on the opposite side of the table-type fixing body in a translation manner, and is used for reflecting the ultrasonic wave emitted by the ultrasonic unit 500 to be calibrated; the connecting piece 1 can adjust the distance as required, and the calibration of multiple distances is guaranteed.

A basic calibration flow: when the calibration of the ultrasonic unit 500 to be calibrated starts, the PC terminal 3 needs to send a calibration start command, and then the ultrasonic ranging automatic gain calibration apparatus in embodiment I of the present invention automatically starts calibration, and realizes gain control by adjusting the resistance of the digital potentiometer U3; when the calibration gain value is adjusted, the gain amplification factor is continuously changed from small to large until an effective echo signal can be stably triggered and generated and the effective echo intensity is reached, and then the calibration gain value of the current measurement distance section is determined.

If the ultrasonic unit 500 to be calibrated needs to perform multi-distance gain value detection, the calibration is performed by segments from near to far, the reflecting part 2 is sequentially translated by segments, if the ultrasonic unit is sequentially moved by 0.5 meter, 1.5 meter and 3 meter … 10 meter, each segment of calibration is completed, corresponding gain and distance values are fed back to the PC end 3, after the calibration operator confirms that the measured distance is correct, the next segment of distance calibration is automatically started, once the module performs all the segment calibrations, the calibration is automatically finished, and the whole calibration process is completed.

Specific example III:

the invention also provides an embodiment:

as shown in fig. 6, an automatic gain calibration method for ultrasonic ranging includes: collecting echo signals sent by the ultrasonic unit 500 to be calibrated at a distance to be measured; performing gain amplification on the echo signal by using a continuously adjustable gain value to obtain the amplified echo signal; acquiring the amplified echo signal, and performing detection processing on the amplified echo signal to obtain a signal after detection processing; comparing the signal after the detection processing with a reference level to obtain an effective echo signal; continuously adjusting the gain value until the effective echo signal can continuously reach the effective echo intensity, and taking the gain value at the moment as a calibration gain value of the ultrasonic unit to be calibrated at the distance to be measured; preferably, when effective echo intensity detection is carried out, the acquisition time t is related to the emission pulse number of the emission end, the number of the emission pulses is generally 8, the emission time of 200us is needed under the frequency of 40KHz, and the emission time t is generally 2-3 times more appropriate.

Specifically, during calibration: the PC end 3 needs to send a calibration starting command, the ultrasonic ranging automatic gain calibration device automatically starts calibration, gain control is achieved by adjusting the resistance value of a digital potentiometer in the gain adjusting unit 202, preferably, the gain amplification factor is changed from small to large until the effective echo signal can continuously reach the effective echo intensity, and the gain value at the moment is used as the calibration gain value of the ultrasonic unit to be calibrated in the distance to be measured; if the gain values of multiple distances need to be detected, the calibration is performed in a segmented mode from near to far, the reflecting piece 2 is sequentially translated in segments, corresponding gain and distance values are fed back to the PC end 3 after the calibration of each segment is completed, and after the calibration operator confirms that the measured distance is correct, the calibration of the next segment is automatically started until all the calibration of the segments is completed.

The above disclosure is only a few specific implementation scenarios of the present invention, however, the present invention is not limited thereto, and any variations that can be made by those skilled in the art are intended to fall within the scope of the present invention. The above-mentioned invention numbers are merely for description and do not represent the merits of the implementation scenarios.