Optimized detection method for ultrasonic fixed-frequency and variable-frequency switching

Abstract

According to the ultrasonic fixed-frequency and variable-frequency switching optimized detection method, a traditional fixed-frequency wave sending mode is changed, a fixed-frequency and variable-frequency switching wave sending mode is adopted, then the detection range of the probes is expanded, cyclic detection is achieved through the multiple probes, and the detection period is shortened. According to the ultrasonic wave fixed frequency and variable frequency switching optimization detection method provided by the invention, through frequency increasing and decreasing operation, a traditional probe which sequentially sends waves can simultaneously send waves twice, the wave sending period is shortened, and due to the fact that the double probes do not interfere with each other, the detection distance can be effectively expanded, and rapidness and range enlargement of probe detection are realized.

Description

Technical Field

[0001] The invention relates to an optimized detection method for ultrasonic fixed-frequency and variable-frequency switching. Background Art

[0002] At present, ultrasonic detection is widely used, especially in vehicles. It not only improves the intelligence of vehicles, but also improves the sense of security and reliability of users during use. However, due to its increasingly widespread use, today's users are too dependent on the detection data of the probe. The vehicle's ultrasonic probe not only becomes the driver's eyes for detecting external information, but also hinders the effectiveness of external information transmission due to the probe's own limitations.

[0003] Because the current probes all explore the outside world by emitting ultrasonic waves with a fixed frequency of more than 40KHz, they themselves will be interfered by the residual vibration of the transmitting probe core, the influence of the wave intensity, and other objective factors, resulting in them being able to only detect a range of 30-180cm, and the cycle of a detection is generally more than 40ms. For intelligent vehicles with increasingly higher requirements, how to expand the detection range and shorten the detection cycle has become a major problem.

[0004] like Figure 1 As shown, due to the fixed detection cycle, traditional single-frequency detection requires a complete detection cycle to confirm the detection of an obstacle. Vehicles with multiple probes need to wait until all probes have completed their transmission before they can confirm the obstacle. The refresh speed is slow, especially for obstacles at a long distance that cannot be captured quickly. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an optimized detection method for ultrasonic fixed-frequency and variable-frequency switching, change the traditional fixed-frequency wave generation mode, adopt a fixed-frequency and variable-frequency switching wave generation mode, thereby expanding the detection range of the probe, and using multiple probes to achieve cyclic detection and reduce the detection cycle.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: An optimized detection method for switching between ultrasonic fixed frequency and variable frequency adopts a variable frequency ultrasonic probe. The probe has two working modes, one is a fixed frequency wave mode and the other is a variable frequency wave mode. The variable frequency wave mode is provided with an increasing frequency wave mode and a decreasing frequency wave mode. The fixed frequency wave mode is set to have a wave root number of 4 and a detection period of 20ms; the variable frequency wave mode is set to have a wave root number of 96 and a detection period of 40ms. The detection method of a single probe is: use the fixed frequency wave mode to detect whether there are obstacles within 15-200cm; if there are no obstacles, switch the working mode to the variable frequency wave mode and perform secondary wave detection. If there are no obstacles, the detection ends. Use the fixed frequency wave mode to detect whether there is an obstacle within 15-200cm; if there is an obstacle, perform a second wave detection in the same wave mode, and calculate the distance difference between the two obstacles through the echo; If the distance difference is within 10cm, the smaller obstacle distance is transmitted; If the obstacle distance is within 15-100cm, the probe is kept in fixed frequency wave mode for subsequent detection; If the obstacle distance is within 120-500cm, the working mode of the probe is changed to variable frequency wave mode for subsequent detection; If the obstacle distance is within 100-120cm, the current working mode of the probe will remain unchanged and subsequent detection will be carried out.

[0007] Furthermore, the detection method of the dual probes is as follows: of the two probes, the first probe transmits waves at an up-frequency in a variable frequency wave transmission mode, and the second probe transmits waves at a down-frequency in a variable frequency wave transmission mode for detection. If an obstacle is found, a second detection is performed in the same mode, and the distance difference between the two obstacles is calculated through echoes; If the distance difference of the first probe is within 10 cm, the smaller obstacle distance is transmitted; If the distance difference of the first probe is greater than 10cm, the working mode of the first probe is maintained for subsequent detection; If the distance difference of the second probe is within 10cm, the smaller obstacle distance is transmitted; If the distance difference of the second probe is greater than 10cm, the working mode of the second probe is maintained for subsequent detection; If there is no obstacle, the detection ends.

[0008] Furthermore, the detection method of the four probes is: the probes are arranged in order as a first probe, a second probe, a third probe and a fourth probe; Step 1: Perform detection in a fixed frequency wave mode in the order of the third probe, the first probe, the fourth probe, and the second probe to determine whether there is an obstacle. If there is an obstacle, proceed to step 2; if there is no obstacle, proceed to step 3. In the second step, if there is an obstacle in the first step, a second wave is sent to confirm the distance of the obstacle. If the distance is within 120cm, continuous detection is performed in a fixed-frequency wave mode according to the initial wave sequence; If the distance is more than 120cm, proceed to step 3; In the third step, the first probe is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, and the third probe is simultaneously operated to emit waves at the down-frequency in the variable frequency mode; then, the second probe is simultaneously operated to emit waves at the down-frequency in the variable frequency mode, and the fourth probe is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, to determine whether the four probes detect obstacles. If there are no obstacles, the process returns to the first step; if there are obstacles, the process proceeds to the fourth step. In the fourth step, if there is an obstacle, a second wave is sent to confirm the distance of the obstacle. If the distance is within 100cm, return to the first step; if the distance is beyond 100cm, return to the third step for continuous detection.

[0009] Furthermore, the fixed frequency wave mode of the probe adopts a frequency of 48KHz.

[0010] Furthermore, the variable frequency wave generation mode of the probe adopts upward frequency modulation of 4KHz and downward frequency modulation of 4KHz.

[0011] Compared with the prior art, the present invention provides an optimized detection method for ultrasonic fixed-frequency and variable-frequency switching. Through frequency up and down operations, a traditional probe that emits waves sequentially can emit waves twice simultaneously, shortening the wave emission cycle. Moreover, because the dual probes will not interfere with each other, the detection distance can be effectively expanded, realizing faster probe detection and expanded range. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 The detection flow chart of the traditional single probe is shown.

[0013] Attached Figure 2 The detection flow chart of the dual probe of the present invention is shown.

[0014] Attached Figure 3 A flow chart of switching detection of a single probe of the present invention is shown.

[0015] Attached Figure 4 The detection flow chart of four probes of the present invention is shown.

[0016] Wherein: in dual-probe detection, the first probe is probe A, and the second probe is probe B; Among the four probes, the first probe is S1, the second probe is S2, the third probe is S3, and the fourth probe is S4. DETAILED DESCRIPTION

[0017] In one embodiment, Figure 3As shown, an optimized detection method for switching between ultrasonic fixed frequency and variable frequency is adopted, and a variable frequency ultrasonic probe is used. The probe has two working modes, one is a fixed frequency wave mode, and the other is a variable frequency wave mode. The variable frequency wave mode is provided with an increasing frequency wave mode and a decreasing frequency wave mode; the fixed frequency wave mode is set to have a wave root number of 4 and a detection period of 20ms; the variable frequency wave mode is set to have a wave root number of 96 and a detection period of 40ms; like Figure 3 As shown, in one embodiment, the detection method of a single probe is: use a fixed frequency wave mode to detect whether there is an obstacle 15-200cm away; if there is no obstacle, switch the working mode to a variable frequency wave mode, perform secondary wave detection, and if there is no obstacle, the detection ends; Use the fixed frequency wave mode to detect whether there is an obstacle within 15-200cm; if there is an obstacle, perform a second wave detection in the same wave mode, and calculate the distance difference between the two obstacles through the echo; If the distance difference is within 10cm, the smaller obstacle distance is transmitted; If the obstacle distance is within 15-100cm, the probe is kept in fixed frequency wave mode for subsequent detection; If the obstacle distance is within 120-500cm, the working mode of the probe is changed to variable frequency wave mode for subsequent detection; If the obstacle distance is within 100-120cm, the current working mode of the probe will remain unchanged and subsequent detection will be carried out.

[0018] like Figure 2 As shown, in one embodiment, the detection method of the dual probes is: of the two probes, the first one transmits waves at an up-frequency in a variable frequency wave transmission mode, and the second one transmits waves at a down-frequency in a variable frequency wave transmission mode for detection. If an obstacle is found, a second detection is performed in the same mode, and the distance difference of the two obstacles is calculated through echoes; If the distance difference of the first probe is within 10 cm, the smaller obstacle distance is transmitted; If the distance difference of the first probe is greater than 10cm, the working mode of the first probe is maintained for subsequent detection; If the distance difference of the second probe is within 10cm, the smaller obstacle distance is transmitted; If the distance difference of the second probe is greater than 10cm, the working mode of the second probe is maintained for subsequent detection; If there is no obstacle, the detection ends.

[0019] like Figure 4 As shown, in one embodiment, the detection method of the four probes is: in order, the probes are arranged as a first probe S1, a second probe S2, a third probe S3 and a fourth probe S4; Step 1: Perform fixed frequency wave detection in the order of the third probe S3, the first probe S1, the fourth probe S4 and the second probe S2 to determine whether there is an obstacle. If there is an obstacle, proceed to step 2; if there is no obstacle, proceed to step 3. In the second step, if there is an obstacle in the first step, a second wave is sent to confirm the distance of the obstacle. If the distance is within 120cm, continuous detection is performed in a fixed-frequency wave mode according to the initial wave sequence; If the distance is more than 120cm, proceed to step 3; In the third step, the first probe S1 is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, and the third probe S3 is simultaneously operated to emit waves at the down-frequency in the variable frequency mode; then, the second probe S2 is simultaneously operated to emit waves at the down-frequency in the variable frequency mode, and the fourth probe S4 is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, and it is determined whether the four probes detect obstacles. If there are no obstacles, the process returns to the first step; if there are obstacles, the process proceeds to the fourth step. In the fourth step, if there is an obstacle, a second wave is sent to confirm the distance of the obstacle. If the distance is within 100cm, return to the first step; if the distance is beyond 100cm, return to the third step for continuous detection.

[0020] Compared with traditional probe detection, the detection distance of the present invention can reach 15-500cm, and the detection period without obstacles is 20X4+40X2=160ms, while the detection distance of the traditional fixed-frequency probe is only 15-400cm and the detection period is 20X4+40X4=240ms. When there are obstacles, the secondary confirmation period of the present invention is fixed frequency: 20X4+20=100ms, variable frequency: 40X2+40=120ms, the traditional fixed-frequency detection short distance is 20X4+20=100ms, and the long distance is 40X4+40=200ms; in summary, the present invention can achieve the advantages of wide detection range, fast obstacle detection speed, fast refresh frequency and the like.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than a limiting technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. An optimized detection method for switching between ultrasonic fixed frequency and variable frequency, characterized in that: A variable frequency ultrasonic probe is used. The probe has two working modes, one is a fixed frequency wave mode and the other is a variable frequency wave mode. The variable frequency wave mode is set to increase the frequency and decrease the frequency. The fixed frequency wave mode is set to 4 wave roots and a detection period of 20ms; the variable frequency wave mode is set to 96 wave roots and a detection period of 40ms. The detection method of a single probe is: use a fixed frequency wave mode to detect whether there are obstacles within 15-200cm; If there is no obstacle, the working mode is switched to variable frequency wave mode, and secondary wave detection is performed. If there is no obstacle, the detection ends. Use fixed frequency wave mode for detection to detect whether there are obstacles within 15-200cm; If there is an obstacle, a second wave detection is performed in the same wave transmission mode, and the distance difference between the two obstacles is calculated through the echo; If the distance difference is within 10cm, the smaller obstacle distance is transmitted; If the obstacle distance is within 15-100cm, the probe is kept in fixed frequency wave mode for subsequent detection; If the obstacle distance is within 120-500cm, the working mode of the probe is changed to variable frequency wave mode for subsequent detection; If the obstacle distance is within 100-120cm, the current working mode of the probe will remain unchanged and subsequent detection will be carried out.

2. The method for optimizing detection of ultrasonic fixed frequency and variable frequency switching according to claim 1, characterized in that: The detection method of the dual probes is as follows: of the two probes, the first one transmits waves at the up-frequency in the variable frequency transmission mode, and the second one transmits waves at the down-frequency in the variable frequency transmission mode. If an obstacle is found, a second detection is performed in the same mode, and the distance difference between the two obstacles is calculated through the echo. If the distance difference of the first probe is within 10 cm, the smaller obstacle distance is transmitted; If the distance difference of the first probe is greater than 10cm, the working mode of the first probe is maintained for subsequent detection; If the distance difference of the second probe is within 10cm, the smaller obstacle distance is transmitted; If the distance difference of the second probe is greater than 10cm, the working mode of the second probe is maintained for subsequent detection; If there is no obstacle, the detection ends.

3. The method for optimizing detection of ultrasonic fixed frequency and variable frequency switching according to claim 1, characterized in that: The detection method of the four probes is: in order, the probes are arranged as a first probe, a second probe, a third probe and a fourth probe; Step 1: Perform detection in a fixed frequency wave mode in the order of the third probe, the first probe, the fourth probe, and the second probe to determine whether there is an obstacle. If there is an obstacle, proceed to step 2; if there is no obstacle, proceed to step 3. In the second step, if there is an obstacle in the first step, a second wave is sent to confirm the distance of the obstacle. If the distance is within 120cm, continuous detection is performed in a fixed-frequency wave mode according to the initial wave sequence; If the distance is more than 120cm, proceed to step 3; In the third step, the first probe is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, and the third probe is simultaneously operated to emit waves at the down-frequency in the variable frequency mode; then, the second probe is simultaneously operated to emit waves at the down-frequency in the variable frequency mode, and the fourth probe is simultaneously operated to emit waves at the up-frequency in the variable frequency mode, to determine whether the four probes detect obstacles. If there are no obstacles, the process returns to the first step; if there are obstacles, the process proceeds to the fourth step. In the fourth step, if there is an obstacle, a second wave is sent to confirm the distance of the obstacle. If the distance is within 100cm, return to the first step; if the distance is beyond 100cm, return to the third step for continuous detection.

4. The method for optimizing detection of ultrasonic fixed frequency and variable frequency switching according to claim 1, characterized in that: The fixed frequency wave mode of the probe adopts a frequency of 48KHz.

5. The method for optimizing detection of ultrasonic fixed frequency and variable frequency switching according to claim 1, characterized in that: The variable frequency wave mode of the probe adopts upward frequency modulation of 4KHz and downward frequency modulation of 4KHz.

Images