Patent Application
20240337558
The embodiments of the present application relate to the technical field of lens loosening tests, in particular to a lens loosening test system and a lens loosening test method.
As one of the important components of automobiles, on-board lens has been continuously upgraded with the development of intelligent vehicles in recent years. In an auto drive system, a lens is the hardware foundation to realize environment recognition and obstacle warning, and the lens is applied to, or the lens serves as a solution more than 80% of the autopilot technology. Due to the special working environment and state of automobiles, the on-board lens needs to have more stable performance to avoid poor imaging performance under long-term vibration environments. Therefore, the on-board lens generally needs to undergo loosening testes before leaving the factory to detect the loosening characteristics of the lens.
In related technologies, there are two main loosening testing solutions for the on-board lens.
One solution is to listen to the sound by human ears after tapping the lens. There may be differences in the sound between a loose lens and a normal lens after tapping, but these differences are often relatively small and require experienced testers to distinguish. Therefore, this solution has high requirements for testers, and the test efficiency is also low, which makes it difficult to ensure the accuracy of test.
Another solution is to detect the imaging performance of the lens after knocking. In response to the imaging performance deteriorating, it indicates that the lens is loose. This solution can achieve automation and does not require manual operation, but the detection rate is actually very low in actual test. Some loose lenses do not cause changes in optical imaging under short-term knocking, and require a considerable period of vibration excitation to possibly cause changes in imaging performance. Therefore, the test effect of this solution is difficult to meet production requirements.
Therefore, it is necessary to provide a lens loosening test system and a lens loosening test method to improve the efficiency and accuracy in loosening test of lens.
The objective of the present application is to provide a lens loosening test system and a lens loosening test method to improve the efficiency and accuracy in loosening test of lens.
The technical solutions of the present application are as follows. A lens loosening test system configured to detect whether a lens to be tested is loose or not is provided, and the lens loosening test system includes a processing module, an acquisition module connected to the processing module, a speaker and a microphone connected to the acquisition module, and a fixing module installed on the speaker;
As an improvement, the lens loosening test system further includes a sound insulation module, where a sound insulation detection environment is formed inside the sound insulation module, and the speaker, the fixing module, and the microphone are arranged inside the sound insulation module.
As an improvement, the lens loosening test system further includes a power amplifier arranged between the acquisition module and the speaker, where the power amplifier is configured to amplify the excitation signal.
As an improvement, the lens loosening test system further includes a preamplifier arranged between the microphone and the acquisition module, where the preamplifier is configured to amplify the audio signal received by the microphone.
As an improvement, the fixing module includes a base fixed on a vibration plate of the speaker and a fixing member arranged on the base, and the fixing member is configured to fix the lens to be tested.
As an improvement, a side of the base away from the speaker inwardly recesses to form a groove for accommodating the lens to be tested, each of side walls of the groove is defined with multiple through holes, the fixing member is a fixing screw, and the fixing screw is threaded with each of the multiple through holes.
A lens loosening test method is provided according to the present application, a lens to be tested is tested using a lens loosening test system according to any one above, and the lens loosening test method includes:
As an improvement, determining, by the processing module, whether the lens to be tested is loose or not based on the audio signal includes:
As an improvement, the lens loosening test method further includes:
The advantageous effect of the present application is that the lens loosening test system provided according to the present application fixes the lens to be tested on the speaker, to drive the lens to be tested to vibrate by the speaker to generate an audio signal, and the audio signal is analyzed by the processing module to determine whether the lens to be tested is loose or not. The lens loosening test system provided according to the present application can effectively detect whether the lens is loose or not with high test efficiency and accuracy.
The present application will be further explained in conjunction with the accompanying drawings and embodiments.
As shown in
The lens loosening test system 100 includes a processing module 1, an acquisition module 2, a speaker 3, a microphone 4, and a fixing module 5. Among them, the processing module 1 is connected to the acquisition module 2, the acquisition module 2 is respectively connected to the speaker 3 and the microphone 4, and the fixing module 5 is fixed to the speaker 3. It should be noted that the connection between the processing module 1, the acquisition module 2, the speaker 3, and the microphone 4 is an electrical signal connection. The acquisition module 2 is an acquisition card, and the processing module 1 is an industrial computer.
Specifically, the fixing module 5 is configured to place and fix the fixing module 5. The processing module 1 is configured to send excitation signals with different excitation frequencies to the acquisition module 2. The excitation signals can be preset and modified according to actual needs, such as excitation signals with multiple frequencies within 300 Hz. After receiving the excitation signal, the speaker 3 is configured to generate vibration to drive the lens to be tested fixed on the fixing module 5 to vibrate and generate an audio signal. The microphone 4 is configured to receive the audio signal and transmit the audio signal to the acquisition module 2. The acquisition 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 to be tested is loose based on the audio signal.
Due to the looseness of the internal components of the lens, under the vibration of the speaker 3, the loosened components of the lens will collide with each other and emit sound different from the lens that is not loose. From a signal perspective, there is signal distortion. Therefore, by analyzing the audio signal collected by the microphone 4, it can be determined whether the lens to be tested is loose or not. The specific methods will be explained in detail hereinafter.
The lens loosening test system provided according to the present application fixes the lens to be tested on the speaker, to drive the lens to be tested to vibrate by the speaker to generate an audio signal, and the audio signal is analyzed by the processing module to determine whether the lens to be tested is loose or not. The lens loosening test system provided according to the present application can effectively detect whether the lens is loose or not with high test efficiency and accuracy.
Furthermore, as shown in
Furthermore, as shown in
Furthermore, as shown in
Furthermore, as shown in
A lens loosening test method is further provided according to the present application, a lens to be tested is tested using a lens loosening test system according to any one above, and the lens loosening test method includes the following operations S10 to S70.
In operation S10, the lens to be tested is fixed on a fixing module.
Specifically, the lens to be tested is arranged in a groove of the base and the lens to be tested is fixed by fixing screws.
In operation S20, an excitation signal is sent by a processing module to an acquisition module.
Specifically, the excitation signals are excitation signals with different excitation frequencies, which can be preset and modified according to actual needs, such as excitation signals with multiple frequencies within 300 Hz. For example, in a range of 50 Hz to 300 Hz, a value is taken every 10 Hz interval as the frequency of the excitation signal, so the excitation signals have with multiple excitation frequencies.
In operation S30, a speaker is excited by the acquisition module based on the excitation signal.
Specifically, the excitation signals sent by the acquisition module 2 can be amplified by the power amplifier 7.
In operation S40, vibration is generated by the speaker to drive the lens to be tested fixed on the fixing module to vibrate and generate an audio signal.
In operation S50, the audio signal is received by the microphone, and the audio signal is transmitted by the microphone to the acquisition module.
Specifically, the audio signal received by the microphone 4 can be amplified by the preamplifier 8.
In operation S60, the audio signal is outputted by the acquisition module to the processing module.
In operation S70, whether the lens to be tested is loose or not is determined by the processing module based on the audio signal.
Specifically, the audio signal is analyzed in the operation S70, as shown in
In sub operation S701, the audio signal is processed by the processing module to obtain a proportion of higher-order harmonics.
Specifically, for any composite periodic vibration function, the Fourier series decomposition is represented as: the first term is called the mean or direct current component, the second term is the fundamental or fundamental vibration, the third term is the second harmonic, and so on. Alternatively, after the second harmonic, they are collectively referred to as higher-order harmonics. In the present application, the processing module 1 is configured to process the audio signal into a composite periodic vibration function, a proportion of higher-order harmonics is a ratio of higher-order harmonics to the composite periodic vibration function.
In sub operation S702, an excitation frequency of the excitation signal is obtained.
Specifically, the excitation signal includes multiple excitation signals with different excitation frequencies, for example, in a range of 50 Hz to 300 Hz, a value is taken every 10 Hz interval as the frequency of the multiple excitation signals.
In sub operation S703, an audio signal curve is drawn based on the proportion of higher-order harmonics and the excitation frequency.
Specifically, the audio signal curve is drawn with the horizontal axis as the excitation frequency and the vertical axis as the proportion of higher-order harmonics.
In sub operation S704, whether a proportion of a part of higher-order harmonics within a preset excitation frequency range is greater than a preset threshold or not is determined based on the audio signal curve.
Specifically, the preset excitation frequency range and the preset threshold can be set according to actual needs. In the present application, the preset excitation frequency range and the preset threshold are obtained through the following operations:
Specifically, multiple lenses that are not loose are obtained first, and the multiple lenses that are not loose are used to obtain the corresponding audio signal through operations S10 to S60. After that, the processing module 1 perform operations S701 to S703 on the obtained audio signal, and a corresponding audio signal curve is drawn based on the proportion of higher-order harmonics obtained from the multiple lens that are not loose and the excitation frequency, the corresponding audio signal curve is taken as a standard curve. The standard curve is analyzed to obtain the preset excitation frequency range and the preset threshold. Specifically, several loose lenses can be tested to obtain audio signal curves. The difference between the audio signal curve of the loose lens and the standard curve can be analyzed, and the excitation frequency range corresponding to the proportion of higher-order harmonics that can distinguish between lenses that are not loose and loose lenses can be identified, and a distinguishing threshold can be defined. For example, in a range of 50 Hz to 300 Hz, the proportion of higher-order harmonics in the standard curve varies very little, not exceeding 0.15. However, in this range, the variation of the proportion of higher-order harmonics in the audio signal curve of the loose lens is very large, and there are several positions exceeding 0.15, so that the preset excitation frequency range can be set to 50 Hz to 300 Hz, and the preset threshold value can be set to 0.15. In response to the lens to be tested being tested, it is only necessary to determine whether the proportion of several higher-order harmonics within the preset excitation frequency range is greater than the preset threshold or not based on the audio signal curve.
In sub operation S705, in response to the proportion of the part of higher-order harmonics within the preset excitation frequency range is greater than the preset threshold, the lens to be tested is determined to be loose.
Specifically, in sub operation S705, in response to the proportion of higher-order harmonics within the preset excitation frequency range being less than the preset threshold, it is determined that the lens to be tested is not loose. In response to there being at least one proportion of higher-order harmonics within the preset excitation frequency range greater than the preset threshold, it is determined that the lens to be tested is loose.
By using the above method, it is possible to effectively detect whether the lens is loose with high test efficiency and accuracy.
The above are only the embodiments of the present application. It should be pointed out that for those of ordinary skill in the art, improvements may be made without departing from the inventive concept of the present application, and the improvements shall fall with the scope of protection of the present application.
The present disclosure is a continuation of PCT Patent Application No. PCT/CN2023/087405, entitled “LENS LOOSENING TEST SYSTEM AND LENS LOOSENING TEST METHOD,” filed Apr. 10, 2023, which is incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2023/087405 | Apr 2023 | WO |
| Child | 18404796 | US |
