Lens looseness testing system and method

Abstract

The present invention provides a lens loosening test system and method. 【Solution means】The lens loosening test system is configured to detect whether the structure of a lens to be detected is loose. The lens loosening test system includes a processing module, a collection module connected to the processing module, a speaker and a microphone respectively connected to the collection module, and a fixing module provided on the speaker. The fixing module is configured to place and fix the lens to be detected. The processing module is configured to send an excitation signal to the collection module. The collection module is configured to excite the speaker based on the excitation signal. The speaker is configured to generate vibrations to vibrate the lens to be detected fixed by the fixing module to generate an audio signal. The microphone is configured to receive the audio signal. The collection module is further configured to output the audio signal to the processing module. The processing module is further configured to determine whether the lens to be detected is loose based on the audio signal. The present invention can accurately detect whether the lens is loose.

Description

[Technical Field]

[0001] The present invention relates to the technical field of lens looseness testing, and more particularly to a lens looseness testing system and method. [Background technology]

[0002] As one of the key components of automobiles, in-vehicle cameras have been continuously upgraded in recent years with the development of smart cars. In autonomous driving systems, cameras are the hardware foundation for environment recognition and obstacle warning, and more than 80% of autonomous driving technologies use cameras or rely on cameras as a solution. Due to the special working environment and conditions of automobiles, in-vehicle lenses require more stable performance to prevent degradation of imaging performance in the automobile's long-term vibration environment. Therefore, in-vehicle lenses often undergo looseness testing to detect looseness characteristics before shipping.

[0003] Currently, there are two main technical proposals for testing the looseness of vehicle lenses: One such technical solution involves tapping the lens and then listening to the sound with a human ear, and there is a difference between the sound produced when a loosened lens is tapped and a normal lens. However, this difference is small and requires an experienced tester to distinguish between the two. Therefore, this technical solution places high demands on the tester, and the test efficiency is very low, making it difficult to guarantee the accuracy of the test.

[0004] Another technical solution is to test the lens's imaging performance after hammering, and if the imaging performance deteriorates, it indicates that the lens is loose. This solution can be automated and does not require manual intervention, but the detection rate is low in actual measurements. Some loose lenses may not show any changes in optical imaging after a short period of hammering, but may only show changes in imaging performance after a considerable period of vibration excitation. Therefore, the testing effect of this solution is difficult to meet production requirements.

[0005] Therefore, there is a need to provide a lens looseness testing system and method to improve the efficiency and accuracy of lens detection. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide a lens looseness testing system and method for improving the efficiency and accuracy of lens detection. [Means for solving the problem]

[0007] The technical solution of the present invention is as follows: a lens loosening test system, configured to detect whether a structure of a target lens is loose, the lens loosening test system comprising: a processing module; an acquisition module connected to the processing module; a speaker and a microphone respectively connected to the acquisition module; and a fixing module provided on the speaker; the fixing module is configured to mount and fix the lens to be detected; the processing module is configured to send an excitation signal to the acquisition module; the acquisition module is configured to excite the speaker based on the excitation signal; the speaker is configured to generate vibrations to vibrate the lens of the detection target fixed to the fixed module to generate an audio signal; the microphone is configured to receive and transmit the audio signal to the acquisition module; the acquisition module is further configured to output the audio signal to the processing module; The processing module is further configured to determine whether the target lens is loose based on the audio signal.

[0008] Illustratively, the device further includes a soundproof module having an interior that is a soundproof detection environment, and the speaker, the fixed module, and the microphone are provided inside the soundproof module.

[0009] Illustratively, the system further comprises a power amplifier disposed between the acquisition module and the speaker, the power amplifier being used to amplify the excitation signal.

[0010] Illustratively, the system further comprises a preamplifier provided between the microphone and the acquisition module, the preamplifier being used to amplify the audio signal received by the microphone.

[0011] Illustratively, the fixing module includes a base fixed to the diaphragm of the speaker and a fixing member provided on the base, and the fixing member is used to fix the lens of the detection target.

[0012] For example, a recessed groove is formed on the side of the base facing away from the speaker to accommodate the lens to be detected, and several through holes are opened in the side wall of the recessed groove. The fixing member is a fixing screw, which is screwed into the through hole.

[0013] The present invention further provides a lens looseness testing method for testing a target lens using the aforementioned lens looseness testing system, the method comprising: Fixing the lens to be detected to the fixing module; transmitting, by a processing module, an excitation signal to an acquisition module; exciting, by the acquisition module, a speaker based on the excitation signal; generating vibrations by the speaker to vibrate the lens of the detection target fixed to the fixed module to generate an audio signal; receiving the audio signal by a microphone and transmitting it to the acquisition module; outputting, by the acquisition module, the audio signal to the processing module; and determining, by the processing module, whether the lens to be detected is loose based on the audio signal.

[0014] Illustratively, the step of determining whether the lens to be detected is loose based on the audio signal by the processing module includes: processing the audio signal by the processing module to obtain a harmonic ratio; obtaining an excitation frequency of the excitation signal; drawing an audio signal curve based on the harmonic proportions and the excitation frequency; determining, based on the audio signal curve, whether a proportion of some harmonics in a predetermined excitation frequency interval is greater than a predetermined threshold; If present, determining that the detected lens is loose.

[0015] Illustratively, the method comprises: testing several loose lenses with the lens looseness testing system; constructing a standard curve based on the harmonic percentages and excitation frequencies obtained from the non-loose lens test; and obtaining the preset excitation frequency interval and the preset threshold value based on the standard curve. [Effects of the Invention]

[0016] The present invention has the following beneficial effects: the lens looseness testing system of the present invention fixes the lens to be detected to a speaker, and vibrates the lens to be detected by the vibration of the speaker to generate an audio signal, and then a processing module analyzes the generated audio signal to determine whether the lens to be detected is loose. The lens looseness testing system of the present invention can effectively detect whether the lens is loose, with high detection efficiency and high accuracy. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram showing the structure of a lens loosening test system of the present invention. [Figure 2] FIG. 2 is a diagram showing the structure of the speaker and fixing module of the lens loosening test system of the present invention. [Figure 3] FIG. 3 is a diagram showing the structure of the fixing module of the lens loosening test system of the present invention. [Figure 4] FIG. 4 is a flow chart of the lens looseness testing method of the present invention. [Figure 5] FIG. 5 is a flowchart showing the process of determining whether or not the lens to be detected is loose in the lens loosening test method of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be further described below in conjunction with the drawings and embodiments.

[0019] As shown in FIGS. 1 and 2, FIG. 1 is a diagram showing the structure of a lens looseness test system of the present invention, and FIG. 2 is a diagram showing the structures of a speaker 3 and a fixing module 5 of the lens looseness test system of the present invention. The lens looseness test system 100 of the present invention is configured to detect whether the structure of the lens to be detected is loose, and more specifically, to detect whether there is looseness in the internal parts of the lens to be detected. In this embodiment, the lens to be detected is an in-vehicle lens, but in other embodiments, tests may be performed on other lenses and are not limited thereto.

[0020] The lens looseness test system 100 includes a processing module 1, an acquisition module 2, a speaker 3, a microphone 4, and a fixing module 5. Here, the processing module 1 is connected to the acquisition module 2, which is connected to the speaker 3 and the microphone 4, respectively, and the fixing module 5 is fixed to the speaker 3. Note that the connections between the processing module 1, acquisition module 2, speaker 3, and microphone 4 are electrical signal connections. The acquisition module 2 is an acquisition card, and the processing module 1 is an industrial personal computer.

[0021] Specifically, the fixing module 5 is configured to mount and fix the lens of the object to be detected. The processing module 1 is configured to send an excitation signal to the collection module 2, the excitation signal being an excitation signal with a different excitation frequency, which can be preset and modified according to actual needs. For example, the excitation signal is an excitation signal with multiple frequencies within 300 Hz. After receiving the excitation signal, the speaker 3 is configured to generate vibrations to vibrate the lens of the object to be detected fixed to the fixing module 5 and generate an audio signal. The microphone 4 is configured to receive the audio signal and transmit it to the collection module 2. The collection module 2 is further configured to output the audio signal to the processing module 1. The processing module 1 is further configured to determine whether the lens of the object to be detected is loose based on the audio signal.

[0022] If there is looseness in the internal structure of a loose lens, the loose lens structures will collide with each other under the vibration of the speaker 3, emitting a sound different from that of a lens that is not loose, and analyzing the signal angle will reveal that there is signal distortion. Therefore, by analyzing the audio signal collected by the microphone 4, it can be determined whether the lens to be detected is loose. The specific method will be described in detail later.

[0023] The lens looseness test system 100 of the present invention fixes the lens to be detected to a speaker 3, and generates an audio signal by vibrating the lens to be detected using the vibration of the speaker 3. The generated audio signal is then analyzed by the processing module 1 to determine whether the lens to be detected is loose. The lens looseness test system 100 of the present invention can effectively detect whether a lens is loose, with high detection efficiency and high accuracy.

[0024] 1, the lens loosening test system 100 of the present invention further includes a soundproof module 6. The soundproof module 6 may be a soundproof box, the interior of which is a soundproof detection environment, and the speaker 3, the fixing module 5, and the microphone 4 are installed inside the soundproof module 6. The soundproof box allows the microphone 4 to better receive the audio signal and blocks the influence of the external environment, thereby avoiding inaccuracies in testing caused by external noise.

[0025] 1, the lens looseness test system 100 of the present invention further includes a power amplifier 7 disposed between the acquisition module 2 and the speaker 3, and the power amplifier 7 is configured to amplify the excitation signal. Specifically, one end of the power amplifier 7 is connected to the acquisition module 2, and the other end of the power amplifier 7 is connected to the speaker 3. The arrangement of the power amplifier 7 makes it possible to amplify the excitation signal transmitted by the acquisition module 2 and generate a driving force sufficient to drive the speaker 3.

[0026] 1, the lens looseness test system 100 of the present invention further includes a preamplifier 8 disposed between the microphone 4 and the collection module 2, and the preamplifier 8 is configured to amplify the audio signal received by the microphone 4. Specifically, one end of the preamplifier 8 is connected to the microphone 4, and the other end of the preamplifier 8 is connected to the collection module 2. The arrangement of the preamplifier 8 allows the audio signal collected by the microphone 4 to be amplified.

[0027] 2 and 3, the fixing module 5 includes a base fixed to the diaphragm of the speaker 3 and a fixing member provided on the base, the fixing member being used to fix the lens to be detected. In this embodiment, a recessed groove is formed on the side of the base away from the speaker 3, recessed inward to accommodate the lens to be detected, several through holes are formed in the side wall of the recessed groove, and the fixing member is a fixing screw that is screwed into the through hole. In other embodiments, the fixing module 5 may adopt other implementations to fix the lens to be detected, for example, a clamping structure may be adopted.

[0028] The present invention further provides a lens looseness test method in which the above-mentioned lens looseness test system 100 performs a test on a lens to be detected, the method including steps S10 to S70: In step S10, the lens to be detected is fixed to the fixing module.

[0029] In step S10, the lens to be detected is placed in the groove of the base, and the lens to be detected is fixed by the fixing screw.

[0030] In step S20, the processing module sends an excitation signal to the acquisition module.

[0031] In step S20, the excitation signal is an excitation signal with different excitation frequencies, which can be preset and modified according to actual needs, for example, the excitation signal is an excitation signal with multiple frequencies within 300 Hz, for example, the frequency of the excitation signal takes one value every 10 Hz within the range of 50-300 Hz, so that the excitation signal is a signal with multiple excitation frequencies.

[0032] In step S30, the collecting module excites a speaker based on the excitation signal.

[0033] In step S30, the power amplifier 7 can amplify the excitation signal transmitted by the acquisition module 2.

[0034] In step S40, the speaker generates vibrations to vibrate the lens of the detection target fixed to the fixed module to generate an audio signal.

[0035] In step S50, the audio signal is received by a microphone and transmitted to the collection module.

[0036] In step S50, the preamplifier 8 can amplify the audio signal received by the microphone 4.

[0037] In step S60, the acquisition module outputs the audio signal to the processing module.

[0038] In step S70, the processing module determines whether the lens to be detected is loose based on the audio signal.

[0039] Specifically, the audio signal is analyzed in step S70, and as shown in FIG. 5, step S70 includes the following steps: In step S701, the processing module processes the audio signal to obtain the proportion of harmonics.

[0040] In step S701, for any complex periodic oscillation function, when expressed by Fourier series decomposition, the first term is called the average value or DC component, the second term is the fundamental wave or fundamental oscillation, and the third term is called the second harmonic. By analogy, the second harmonic and subsequent terms are collectively called harmonics. In the present invention, the processing module 1 processes the audio signal and converts it into a complex periodic oscillation function, and the proportion of harmonics is the proportion of harmonics that harmonics occupy in the complex periodic oscillation function.

[0041] In step S702, the excitation frequency of the excitation signal is obtained.

[0042] In step S702, the excitation signal is an excitation signal with different excitation frequencies, for example, the frequency of the excitation signal is taken as one value at every 10 Hz interval within the range of 50-300 Hz.

[0043] In step S703, an audio signal curve is drawn based on the harmonic proportion and the excitation frequency.

[0044] In step S703, an audio signal curve is plotted with the excitation frequency on the horizontal axis and the percentage of harmonics on the vertical axis.

[0045] In step S704, it is determined based on the audio signal curve whether the proportion of some harmonics in the preset excitation frequency interval is greater than a preset threshold.

[0046] In step S704, the preset excitation frequency range and the preset threshold value can be set according to actual needs. In the present invention, the preset excitation frequency range and the preset threshold value are: The lens loosening test system 100 performs tests on several non-loose lenses, draws a standard curve based on the harmonic ratio and excitation frequency obtained from the non-loose lens tests, and obtains the preset excitation frequency interval and the preset threshold value based on the standard curve.

[0047] Specifically, a number of non-loose lenses are first obtained, and corresponding audio signals are obtained from the non-loose lenses through steps S10 to S60. Next, the processing module 1 performs steps S701 to S703 on the obtained audio signals, plotting corresponding audio signal curves based on the harmonic ratios and excitation frequencies obtained from the non-loose lens tests, which are used as standard curves. The standard curves are analyzed to set the preset excitation frequency ranges and the preset thresholds. Specifically, several loose lenses are tested to obtain corresponding audio signal curves, and the difference between the audio signal curves of the loose lenses and the standard curves is analyzed to find the excitation frequency ranges corresponding to the harmonic ratios that can distinguish between non-loose lenses and loose lenses, and then the thresholds for distinction are set. For example, if the standard curve shows only small changes in the proportion of harmonics within 50-300 Hz, none of which exceed 0.15, but the audio signal curve of a loose lens shows very large fluctuations in the proportion of harmonics within this range, with some points exceeding 0.15, the preset excitation frequency range can be set to 50-300 Hz and the preset threshold value can be set to 0.15. When testing the lens to be detected, it is only necessary to determine based on the audio signal curve whether the proportion of some harmonics in the preset excitation frequency range is greater than the preset threshold value.

[0048] In step S705, if present, it is determined that the lens to be detected is loose.

[0049] Specifically, in step S705, if the proportions of all harmonics within the preset excitation frequency range are smaller than the preset threshold, it is determined that the lens to be detected is not loose, and if the proportion of at least one harmonics within the preset excitation frequency range is greater than the preset threshold, it is determined that the lens to be detected is loose.

[0050] The above-described method can effectively detect whether the lens is loose, with high detection efficiency and high accuracy.

[0051] The above is merely an embodiment of the present application, and as should be pointed out here, those skilled in the art may make improvements without departing from the creative concept of the present invention, all of which fall within the scope of protection of the present application.

Claims

1. A lens looseness test system for detecting whether a structure of a lens to be detected is loose, comprising: a single processing module; a collection module connected to the processing module; a speaker and a microphone respectively connected to the collection module; and a fixing module provided on the speaker; the fixing module is configured to mount and fix the lens to be detected; the processing module is configured to send an excitation signal to the acquisition module; the acquisition module is configured to excite the speaker based on the excitation signal; the speaker is configured to generate vibrations to vibrate the lens of the detection target fixed to the fixed module to generate an audio signal; the microphone is configured to receive and transmit the audio signal to the acquisition module; the acquisition module is further configured to output the audio signal to the processing module; the processing module is further configured to determine whether the target lens is loose based on the audio signal; The processing module includes: processing the audio signal to obtain a proportion of harmonics; obtaining an excitation frequency of the excitation signal; drawing an audio signal curve based on the harmonic proportions and the excitation frequency; determining whether a proportion of certain harmonics in a predetermined excitation frequency interval is greater than a predetermined threshold based on the audio signal curve; If present, determining that the detected lens is loose. A lens loosening test system.

2. The lens loosening test system comprises: The device further includes a soundproof module, the inside of the soundproof module being a soundproof detection environment, and the speaker, the fixing module, and the microphone being provided inside the soundproof module.

2. The lens loosening test system according to claim 1.

3. The lens loosening test system comprises: Further comprising a power amplifier disposed between the acquisition module and the speaker, the power amplifier being used to amplify the excitation signal; 2. The lens loosening test system according to claim 1.

4. The lens loosening test system comprises: Further comprising a preamplifier disposed between the microphone and the acquisition module, the preamplifier being used to amplify the audio signal received by the microphone.

2. The lens loosening test system according to claim 1.

5. the fixing module includes a base fixed to a diaphragm of the speaker and a fixing member provided on the base, the fixing member being used to fix the lens to be detected; 2. The lens loosening test system according to claim 1.

6. A recessed groove is formed on the side of the base away from the speaker, the recessed groove being recessed inward to accommodate the lens to be detected, and several through holes are formed in the side wall of the recessed groove. The fixing members are fixing screws, and the fixing screws are screwed into the through holes.

6. The lens loosening test system according to claim 5.

7. A method for testing lens looseness, the method comprising: testing a lens to be detected using a lens looseness testing system according to any one of claims 1 to 6; The method comprises: Fixing the lens to be detected to the fixing module; transmitting, by a processing module, an excitation signal to an acquisition module; exciting, by the acquisition module, a speaker based on the excitation signal; generating vibrations by the speaker to vibrate the lens of the detection target fixed to the fixed module to generate an audio signal; receiving the audio signal by a microphone and transmitting it to the acquisition module; outputting, by the acquisition module, the audio signal to the processing module; determining, by the processing module, whether the lens to be detected is loose based on the audio signal; Including, A method for testing lens looseness.

8. The method comprises: testing several loose lenses with the lens looseness testing system; constructing a standard curve based on the harmonic percentages and excitation frequencies obtained from the non-loose lens test; obtaining the preset excitation frequency interval and the preset threshold value based on the standard curve; further comprising:

8. The method for testing lens looseness according to claim 7.

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