Sensor inspection and calibration method and system
By using a sensor inspection and calibration system, which utilizes automated processes and autonomous inspection of noise sensors, the problems of low efficiency and poor accuracy in noise sensor calibration in existing technologies are solved, and fully automatic and accurate multi-sensor calibration is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-12
- Publication Date
- 2026-04-07
AI Technical Summary
Existing technologies cannot automatically and efficiently perform comprehensive and accurate testing and calibration of multiple noise sensors, and existing solutions suffer from problems such as high cost, low accuracy, and reliance on manual operation.
A sensor testing and calibration system is adopted, including a controller, an anechoic chamber, a mobile device, a sound-generating device, and a sound analysis device. Through an automated process, multiple noise sensors are calibrated for multi-frequency and multi-amplitude sound waves. Combined with the autonomous testing of noise sensors and result reporting, fully automatic and efficient calibration is achieved.
It enables fully automated and accurate calibration of multiple noise sensors, reduces human error, improves calibration efficiency and accuracy, supports batch calibration, and reduces costs.
Smart Images
Figure CN121804646A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of sensor technology, and more specifically, to a sensor testing and calibration method and system. Background Technology
[0002] Noise sensors, as a key acoustic measurement device, are increasingly widely used in various fields, such as environmental noise monitoring and control, and monitoring and fault early warning of the operating status of important industrial equipment. With the continuous expansion and deepening of application scenarios, the market demands higher and higher quality, accuracy, measurement range, and production capacity for noise sensors.
[0003] To ensure the accuracy and reliability of noise sensors, calibration and inspection are required before shipment. Existing technologies include: some solutions incorporate a standard transmitter within the noise sensor for online self-calibration, but this often only allows calibration within specific frequency bands and intensities, failing to provide wide-range calibration and significantly increasing costs; others enhance the sensor's pickup capability through novel acoustic cavity structures, but this does not improve accuracy; some design integrated multi-band transmitters to calibrate a single noise sensor across multiple frequency bands, but cannot automate the calibration of multiple sensors; and still others use laser positioning devices for auxiliary reference positioning, but these rely on manual operation and cannot be automated.
[0004] Therefore, existing technologies cannot automatically and efficiently perform comprehensive and accurate testing and calibration of multiple noise sensors. Summary of the Invention
[0005] The purpose of this application is to provide a sensor inspection and calibration method and system to improve the above-mentioned problems.
[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a sensor testing and calibration method applied to a sensor testing and calibration system. The sensor testing and calibration system includes a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are disposed within the anechoic chamber. The moving device can drive the multiple noise sensors into or out of the anechoic chamber. The anechoic chamber provides a test environment isolated from external noise. The sensor testing and calibration method includes: The controller responds to the start test command and controls the mobile device to bring multiple noise sensors into the anechoic chamber. The controller controls the sound-generating device to sequentially emit multiple sound waves of different frequency bands and amplitudes; The acoustic analysis device acquires the reference acoustic characteristics of the current sound wave and uploads the reference acoustic characteristics to the controller; The controller sends the reference acoustic features to each of the noise sensors and simultaneously triggers each of the noise sensors to collect the measured acoustic features of the current sound wave. Each noise sensor checks its own compliance based on the multiple measured acoustic features it collects and the multiple reference acoustic features it receives, obtains the test results, and reports them to the controller.
[0007] Optionally, the measured acoustic features include measured frequency and measured amplitude, and the reference acoustic features include reference frequency and reference amplitude; Each noise sensor verifies its own compliance based on multiple measured acoustic features it has acquired and multiple received reference acoustic features, including the following steps: Calculate the frequency deviation between the measured frequency and the reference frequency for each group, and determine whether the frequency deviation is within a first preset range; Calculate the amplitude deviation between the measured amplitude and the reference amplitude for each group, and determine whether the amplitude deviation is within the second preset range; If any of the frequency deviations exceeds the first preset range or any of the amplitude deviations exceeds the second preset range, the noise sensor is deemed unqualified; otherwise, the noise sensor is deemed qualified.
[0008] Optionally, the measured acoustic feature includes the measured amplitude, and the reference acoustic feature includes the reference amplitude; the sensor testing and calibration method further includes: If the inspection result is qualified, each noise sensor generates an amplitude calibration curve based on multiple sets of corresponding measured amplitudes and reference amplitudes. The amplitude calibration curve is used to calibrate the measured amplitude of the noise sensor after it leaves the factory.
[0009] Optionally, the parameters of the amplitude calibration curve include calibration slope and drift compensation amplitude, wherein the calibration slope characterizes the degree of distortion of the noise sensor and the drift compensation amplitude characterizes the degree of drift of the noise sensor; The sensor testing and calibration method further includes: Each noise sensor estimates its expected lifespan while maintaining measurement accuracy based on the calibration slope, the drift compensation amplitude, and a pre-stored aging trend database; it sets an expected re-inspection time based on the expected lifespan and prompts for re-inspection when the expected re-inspection time is reached.
[0010] Optionally, the sensor testing and calibration system further includes a rangefinder, which is mounted on the sound-generating device; The sensor testing and calibration method further includes: The controller responds to the start inspection command and triggers the rangefinder to measure the real-time distance between each noise sensor and the sound-generating device; The controller receives the measurement results uploaded by the rangefinder and controls the mobile device to adjust its position according to the measurement results until the real-time distance between each noise sensor and the sound-generating device is equal to the distance between the sound analysis device and the sound-generating device.
[0011] Secondly, this application provides a sensor testing and calibration system, which includes a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are disposed in the anechoic chamber, and the moving device can drive the multiple noise sensors into or out of the anechoic chamber. The anechoic chamber is used to provide a testing environment that isolates external noise; The controller is used to: respond to a start inspection command, control the mobile device to drive multiple noise sensors into the anechoic chamber; and control the sound-generating device to sequentially emit multiple sound waves of different frequency bands and amplitudes. The acoustic analysis device is used to collect reference acoustic features of the current sound wave and upload the reference acoustic features to the controller; The controller is also used to send the reference acoustic features to each of the noise sensors, and at the same time trigger each of the noise sensors to collect the measured acoustic features of the current sound wave; Each noise sensor is used to check whether it is qualified based on the multiple measured acoustic features it has collected and the multiple reference acoustic features it has received, and to obtain the test result and report it to the controller.
[0012] Optionally, the mobile device includes a support, a moving track, a moving control mechanism, and a sensor mounting base; The moving track is laid on the support and passes through the entrance of the anechoic chamber; The sensor mounting base is detachably mounted on the mobile control mechanism for simultaneously mounting multiple noise sensors to be calibrated. Different sensor mounting bases are adapted to different models of noise sensors.
[0013] Optionally, the mobile device further includes an adjustable switching power supply for powering the noise sensor on the sensor mounting base; The sensor testing and calibration system also includes a camera, which is located outside the anechoic chamber and faces the sensor mounting base, for capturing images of the installed noise sensor. The controller is also configured to: receive the image and identify the sensor model information in the image; query a pre-established Enterprise Resource Planning (ERP) system based on the model information to obtain the electrical information corresponding to the model information; and control the adjustable switching power supply to output a DC voltage that matches the electrical information.
[0014] Optionally, the moving track has a hollow structure with a power supply reel inside. The power supply reel is connected to an external power source, and the moving control mechanism is connected to the power supply reel via a first cable. The sensor mounting base is provided with multiple second cables, and each noise sensor mounted on the sensor mounting base is connected to the adjustable switching power supply through the corresponding second cable.
[0015] Optionally, the anechoic chamber is equipped with an automatic door, which is a double-leaf structure and has a flexible sealing material on the edge of the door. The controller is also configured to: respond to the start inspection command, open the automatic door, control the mobile device to drive multiple noise sensors into the anechoic chamber, and close the automatic door to isolate external noise after confirming that the mobile device has reached the preset inspection station.
[0016] Compared to existing technologies, this application provides a sensor testing and calibration method and system. The sensor testing and calibration system includes a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are located inside the anechoic chamber, which provides a test environment isolated from external noise. During the testing and calibration process, after the controller responds to the start testing command, it controls the moving device to drive multiple noise sensors into the anechoic chamber. Then, it controls the sound-generating device to sequentially emit multiple sound waves of different frequency bands and amplitudes, realizing dynamic calibration of the noise sensors over a wide range and under multiple operating conditions. After emitting sound waves, the acoustic analysis device collects reference acoustic features and uploads them to the controller, which then distributes the data to each noise sensor. Simultaneously, each noise sensor is triggered to collect measured acoustic features, ensuring consistency of sampling conditions, avoiding irregularities and errors caused by manual operation, and improving the accuracy of inspection and calibration. Each noise sensor, based on the received reference acoustic features and its own measured acoustic features, autonomously completes the conformity inspection and reports the results. This overcomes the shortcomings of existing technologies that rely on manual operation, are inefficient, and can only calibrate one sensor at a time. Thus, it can automatically and efficiently perform comprehensive and accurate inspection and calibration of multiple noise sensors. Attached Figure Description
[0017] Figure 1 A schematic diagram of a sensor inspection and calibration system provided in an embodiment of this application is shown.
[0018] Figure 2 for Figure 1 The diagram shows the structure of an automatic door in a sensor testing and calibration system.
[0019] Figure 3 for Figure 1 The diagram shows the structure of the mobile device in the sensor inspection and calibration system.
[0020] Figure 4 This application provides a schematic flowchart of a sensor testing and calibration method according to an embodiment. Figure 1 .
[0021] Figure 5 This application provides a schematic flowchart of a sensor testing and calibration method according to an embodiment. Figure 2 .
[0022] Figure 6 An example graph illustrating the aging trend of a sensor provided in an embodiment of this application is shown.
[0023] Icons: 100-Sensor testing and calibration system; 110-Controller; 120-Anechoic chamber; 121-Automatic door; 130-Moving device; 131-Bracket; 132-Moving track; 133-Moving control mechanism; 134-Sensor mounting base; 135-Adjustable switching power supply; 136-Power cable reel; 140-Sound generating device; 150-Sound analysis device; 160-Noise sensor; 170-Range meter; 180-Camera. Detailed Implementation
[0024] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0025] Please refer to Figure 1 This application provides a sensor testing and calibration system, including a controller 110, an anechoic chamber 120, a mobile device 130, a sound-generating device 140, a sound analysis device 150, and a plurality of noise sensors 160 to be calibrated. The controller 110 is connected to the mobile device 130, the sound-generating device 140, the sound analysis device 150, and each noise sensor 160, respectively, and the connection can be wired or wireless.
[0026] The anechoic chamber 120 is used to provide a test environment that isolates external noise. In other words, the anechoic chamber 120 can reduce the external ambient noise to below 20dB, so that the entire inspection and calibration process is free from the influence of external noise and improves the effect of inspection and calibration.
[0027] The mobile device 130 can drive multiple noise sensors 160 into or out of the anechoic chamber 120.
[0028] The controller 110 is the control core of the sensor inspection and calibration system 100. It is used to run a fully automatic inspection and calibration program to complete the inspection and calibration of multiple (e.g., 30) noise sensors 160 at one time.
[0029] Optionally, when the operator starts the inspection and calibration procedure, the controller 110 responds to the start inspection command and sends a forward command to the mobile device 130. Driven by the forward command, the mobile device 130 drives multiple noise sensors 160 into the anechoic chamber 120.
[0030] After confirming that the mobile device 130 has reached the preset detection station (e.g., the left limit), the controller 110 starts to control the sound-emitting device 140 to work, causing it to emit multiple sound waves of different frequency bands and amplitudes in sequence. That is, the sound-emitting device 140 sends multiple frequency bands in sequence, and each frequency band sends multiple sound waves of different amplitudes in sequence. Taking a single operation as an example, the controller 110 issues a sound-emitting command, the sound-emitting device 140 receives the sound-emitting command, and emits a sound wave of a specified frequency band (e.g., 20Hz~1000Hz), a specified amplitude (e.g., 80 dB), and a specified duration (e.g., 30s).
[0031] The acoustic analysis device 150 is used to collect the reference acoustic characteristics of the current sound wave and upload the reference acoustic characteristics to the controller. That is, after the sound generating device 140 emits a sound wave, the acoustic analysis device 150 measures the sound wave. The acoustic analysis device 150 is a high-precision, large-range professional acoustic instrument that can accurately capture the reference acoustic characteristics (including reference frequency and reference amplitude) of the current sound wave and upload these data to the controller 110.
[0032] The controller 110 is also used to send reference acoustic features to each noise sensor 160, and simultaneously trigger each noise sensor 160 to collect the measured acoustic features of the current sound wave. That is, the controller 110 sends the reference acoustic features measured by the acoustic analysis device 150 to each noise sensor 160 to be calibrated, and simultaneously sends sampling commands to them, triggering each noise sensor 160 to collect the measured acoustic features of the current sound wave, including the measured frequency and measured amplitude.
[0033] In this way, after each sound wave is emitted by the sound-emitting device 140, each noise sensor 160 will obtain a corresponding set of reference acoustic characteristics and its own measured acoustic characteristics. Throughout the entire testing and calibration process, this cycle of "sound-emitting device 140 emitting sound waves, sound analysis device 150 collecting reference acoustic characteristics, and each noise sensor 160 collecting measured acoustic characteristics" will be repeated many times, covering multiple frequency bands and multiple amplitude combinations, forming multiple sets of comparative data.
[0034] For example, after confirming that the mobile device 130 has reached the preset detection station (e.g., the left limit), the controller 110 issues a sound-emitting command for frequency band 1 and amplitude 1, the sound-emitting device 140 emits sound waves for frequency band 1 and amplitude 1, the sound analysis device 150 collects and analyzes the sound waves, and reports the reference frequency f1 and reference amplitude p11. The controller 110 issues a sampling command, and sends the reference frequency f1 and reference amplitude p11. Each noise sensor 160 collects and analyzes the sound waves, and records the measured frequency fz1, measured amplitude pz11, reference frequency f1, and reference amplitude p11. This process is repeated multiple times, covering multiple frequency bands and multiple amplitude combinations, to obtain multiple sets of corresponding reference acoustic features and measured acoustic features.
[0035] Each noise sensor 160 is used to verify its own compliance based on multiple measured acoustic features it has collected and multiple received reference acoustic features, obtain the verification result, and report it to the controller 110. That is, each noise sensor 160 autonomously determines whether its response is within the allowable error range based on multiple sets of corresponding reference acoustic features and measured acoustic features it has recorded, and then draws a conclusion on whether it is qualified, and sends the verification result back to the controller 110 for aggregation.
[0036] Please refer to this again. Figure 1 The mobile device 130 includes a support 131, a moving track 132, a moving control mechanism 133, and a replaceable sensor mounting base 134. The moving track 132 is laid on the support 131 and passes through the entrance of the anechoic chamber 120. The support 131 is fixed to the ground and supports the moving track 132. Its height is rationally designed so that the moving track 132 can smoothly pass through the automatic door 121 and extend to the predetermined detection position inside the anechoic chamber 120. The moving control mechanism 133 can move back and forth along the moving track 132 under the command of the controller 110, realizing fully automatic transfer of the noise sensor between the loading / unloading station and the detection station.
[0037] The sensor mounting base 134 is detachably mounted on the motion control mechanism 133 for simultaneously mounting multiple noise sensors 160 to be calibrated. Different sensor mounting bases are adapted to different models of noise sensors 160.
[0038] Optionally, the sensor mounting base 134 adopts a modular design, supporting quick disassembly and replacement. A single sensor mounting base 134 can simultaneously hold up to 30 noise sensors 160, enabling batch calibration in one go and significantly improving work efficiency. Furthermore, different types of sensor mounting bases 134 are compatible with sensor products of different shapes, sizes, and interface types. While the replacement of the sensor mounting base 134 is done manually, the subsequent identification and configuration processes are automated.
[0039] Please refer to Figure 2 The anechoic chamber 120 is equipped with an automatic door 121, which is a double-opening structure. The middle of the door body is reserved for the passage of the moving track, and is slightly wider than the track by 5mm to avoid interference during operation. At the same time, the edges of the door body are equipped with flexible sealing material (e.g., cotton blocks). When the automatic door 121 is closed, the edges of the door seam are tightly sealed by the flexible sealing material, further blocking the transmission of external noise and ensuring the consistency of the test environment.
[0040] The controller is also used to: respond to the start inspection command, open the automatic door 121, control the moving device 130 to drive multiple noise sensors 160 into the anechoic chamber 120, and close the automatic door 121 to isolate external noise after confirming that the moving device 130 has reached the preset inspection station.
[0041] That is, when the mobile device 130 carries the noise sensor 160 to be calibrated into the anechoic chamber 120, the automatic door 121 closes to form a closed testing environment. After the inspection and calibration task is completed, the automatic door 121 opens again and the mobile device 130 exits to the loading and unloading station, which facilitates manual replacement of the sensor or the next batch of work.
[0042] Optionally, the preset detection station can be the left limit of the moving track 132, or it can be a position where the distance between the preset detection station and the sound generating device 140 is equal to the distance between the sound analysis device 150 and the sound generating device 140. That is, the distance between the preset detection station and the sound generating device 140 is the same as the distance between the sound analysis device 150 and the sound generating device 140.
[0043] Please refer to this again. Figure 1 The sensor inspection and calibration system 100 also includes a rangefinder 170, which is mounted on the sound-generating device 140. The controller 110 is also used to: respond to the start inspection command, trigger the rangefinder 170 to measure the real-time distance between each noise sensor 160 and the sound-generating device 140; receive the measurement results uploaded by the rangefinder 170, and control the moving device 130 to adjust its position according to the measurement results until the real-time distance between each noise sensor and the sound-generating device is equal to the distance between the sound analysis device 150 and the sound-generating device 140.
[0044] That is, the rangefinder 170 can measure the distance information between each noise sensor 160 and the sound-generating device 140 and transmit it to the controller 110. The controller 110 controls the moving device 130 to move to the left until the distance between each noise sensor 160 and the sound-generating device 140 is consistent with the distance between the sound analysis device 150 and the sound-generating device 140. In this way, the noise sensors 160 of different sizes can be aligned with the position of the sound analysis device 150 during inspection and calibration, thereby ensuring calibration accuracy.
[0045] Please refer to Figure 3 The mobile device 130 also includes an adjustable switching power supply 135 for powering the noise sensor 160 on the sensor mounting base 134.
[0046] The sensor inspection and calibration system 100 also includes a camera 180, which is located outside the anechoic chamber 120 and faces the sensor mounting base 134, for capturing images of the installed noise sensor 160.
[0047] The controller 110 is also used to: receive images and identify the model information of the sensors in the images; query the pre-established Enterprise Resource Planning (ERP) system according to the model information to obtain the electrical information corresponding to the model information; and control the adjustable switching power supply 135 to output a DC voltage that matches the electrical information.
[0048] That is, the camera 180 captures images of the sensor array on the sensor mounting base 134 and transmits them to the controller 110. The controller 110 identifies the specific model of each sensor through a built-in image recognition algorithm and automatically retrieves the corresponding electrical parameters (such as the rated power supply voltage) from the ERP system. Subsequently, the controller 110 controls the adjustable switching power supply 135 on the mobile device 130 to provide matching power supply voltages (such as 5V or 24V) to different types of sensors, thereby achieving power supply self-adaptation.
[0049] Optionally, the moving track 132 has a hollow structure, and a power supply cable reel 136 is installed inside. The power supply cable reel 136 is connected to an external power source, and the moving control mechanism 133 is connected to the power supply cable reel 136 via a first cable. The sensor mounting base 134 is provided with multiple second cables, and each noise sensor 160 mounted on the sensor mounting base 134 is connected to the adjustable switching power supply 135 via a corresponding second cable.
[0050] The operation of the entire sensor inspection and calibration system 100 is uniformly scheduled by the controller 110. Users only need to click "Start Automatic Inspection and Calibration" on the human-machine interface, and the sensor inspection and calibration system 100 can automatically complete the entire inspection and calibration process according to the preset program without the need for manual intervention in specific operation steps.
[0051] Optionally, the controller 110 can be a hardware device with automation control and data processing capabilities, such as an industrial computer, a programmable logic controller, a host computer system, an embedded control system, or an industrial panel PC.
[0052] Optionally, the noise sensor 160 may include a processing unit, a communication module, a sampling module, an analysis module, and a storage module. The processing unit coordinates and manages the operation of each module; the sampling module collects raw audio data of the current sound wave; the analysis module analyzes the frequency band, amplitude, and other information of the raw audio data to obtain measured acoustic characteristics; the storage module stores historical acoustic characteristic data, calibration parameters, and other information; the communication module supports bidirectional communication with the controller 110, can receive control signals and reference acoustic characteristics from the controller 110, and report its own test results and operating status.
[0053] The following is a test and calibration method applied to the above-mentioned sensor test and calibration system 100.
[0054] Please refer to Figure 4 , Figure 4 The diagram illustrates a flow chart of a sensor testing and calibration method provided in an embodiment of this application. This sensor testing and calibration method may include the following steps: S101, the controller responds to the start test command and controls the moving device to drive multiple noise sensors into the anechoic chamber.
[0055] S102, the controller controls the sound-generating device to emit multiple sound waves of different frequencies and amplitudes in sequence.
[0056] S103, the acoustic analysis device collects the reference acoustic characteristics of the current sound wave and uploads the reference acoustic characteristics to the controller.
[0057] S104, the controller sends the reference acoustic characteristics to each noise sensor, and at the same time triggers each noise sensor to collect the measured acoustic characteristics of the current sound wave.
[0058] S105, each noise sensor checks its own qualification based on multiple measured acoustic features collected by itself and multiple reference acoustic features received, obtains the test results and reports them to the controller.
[0059] In this embodiment, when the operator initiates the inspection and calibration procedure, the controller responds to the start inspection command, initiates the calibration process, and sends a control command to the mobile device, driving it to carry all the noise sensors to be calibrated from the loading and unloading station into the anechoic chamber. Optionally, the loading and unloading station is a non-working position used for installing and removing the noise sensors.
[0060] Once all the noise sensors to be calibrated are sent into the anechoic chamber and arrive at the preset testing station, the controller instructs the sound-generating device to sequentially emit multiple sound waves with different frequency bands and amplitudes. Optionally, the sound waves emitted by the sound-generating device can cover the typical frequency range (such as low frequency, mid frequency, and high frequency) that the noise sensors may respond to in practical applications, as well as different intensity levels (i.e., sound volume), to comprehensively test the sensitivity and accuracy of each noise sensor throughout its operating range.
[0061] After the sound-generating device emits a sound wave, the sound analysis device simultaneously acquires the reference acoustic characteristics of the current sound wave. The reference acoustic characteristics may include a reference frequency and a reference amplitude. Since the sound analysis device itself is calibrated regularly, its measurement results have high reliability and can therefore be used as a reference standard for the testing and calibration of noise sensors.
[0062] After obtaining the reference acoustic characteristics, the acoustic analysis device uploads them to the controller, which then distributes them to each noise sensor. At the same time, the controller also sends a sampling signal to each noise sensor, instructing the noise sensor to sample the current sound wave to obtain the measured acoustic characteristics, which may include the measured frequency and measured amplitude.
[0063] Thus, after repeating the process of "sound generating device 140 emitting sound waves, sound analysis device 150 collecting reference acoustic features, and each noise sensor 160 collecting measured acoustic features" multiple times, each noise sensor can obtain multiple sets of corresponding measured acoustic features and reference acoustic features.
[0064] Subsequently, the noise sensor runs a preset verification algorithm to compare and analyze each set of corresponding measured acoustic features with reference acoustic features, assessing whether the deviation between the two is within the allowable tolerance range. If the deviation between any set of measured acoustic features and the reference acoustic features exceeds the allowable tolerance range, the sensor is deemed unqualified; otherwise, it is deemed qualified, and the verification result is obtained and reported to the controller. In this way, by verifying the qualification of each noise sensor locally, the data processing burden on the controller is reduced, and the overall system response speed and reliability are improved.
[0065] In one possible implementation, taking any noise sensor as an example, step S105, which involves verifying the sensor's own compliance based on multiple measured acoustic features acquired and multiple received reference acoustic features, may include: Calculate the frequency deviation between the measured frequency and the reference frequency for each group, and determine whether the frequency deviation is within the first preset range. Calculate the amplitude deviation between the measured amplitude and the reference amplitude for each group, and determine whether the amplitude deviation is within the second preset range; If any frequency deviation exceeds the first preset range or any amplitude deviation exceeds the second preset range, the noise sensor is deemed unqualified; otherwise, the noise sensor is deemed qualified.
[0066] In this embodiment, for each set of corresponding measured and reference frequencies, the noise sensor calculates the ratio between them, i.e., fzn / fn, where fzi and fi represent the measured and reference frequencies of the sound wave in the specified frequency band n, respectively, to obtain the frequency deviation. The frequency deviation reflects the accuracy of the noise sensor in sensing sound frequencies. Then, the noise sensor further determines whether each frequency deviation is within a first preset range (e.g., 0.9~1.1), i.e., whether 0.9≤fzn / fn≤1.1 holds true. If any frequency deviation exceeds the first preset range, it is determined to be unqualified; otherwise, an amplitude judgment is performed.
[0067] In amplitude determination, for each set of corresponding measured amplitude and reference amplitude, the noise sensor calculates the ratio between them, i.e., pznm / pnm, where pznm and pnm represent the measured amplitude and reference amplitude of a sound wave with a specified frequency band of n and a specified amplitude of m, respectively, to obtain the amplitude deviation. Then, the noise sensor further determines whether each amplitude deviation is within a second preset range (e.g., 0.9~1.1), i.e., whether 0.9≤pznm / pnm≤1.1 holds true. If any amplitude deviation exceeds the second preset range, it is determined to be unqualified; otherwise, it is determined to be qualified.
[0068] In other words, a noise sensor is considered qualified only if all frequency deviations and all amplitude deviations meet their respective preset ranges.
[0069] Optionally, the first and second preset ranges are derived from empirical values. Exceeding these ranges is often due to quality issues and is not worth further calibration; the affected parts should be scrapped. Otherwise, further calibration should be performed to achieve higher accuracy.
[0070] After each noise sensor completes its own pass / fail inspection, it uploads the generated inspection results to the controller. Optionally, the inspection results may include at least the measured acoustic characteristics collected each time and the inspection result (pass / fail). After receiving the inspection results reported from all noise sensors, the controller can further summarize them to form a quality inspection report, which can be viewed by operators or imported into the quality management system.
[0071] In practical applications of noise sensors, their measurement accuracy depends not only on the pre-shipment inspection and calibration process, but also on their ability to dynamically correct the measured amplitude during subsequent use. Therefore, even noise sensors that have passed inspection require further calibration to improve their measurement accuracy after leaving the factory.
[0072] Therefore, in Figure 4 Based on this, please refer to Figure 5 After step S105, the sensor inspection and calibration method provided in this application embodiment further includes step S106.
[0073] S106, if the inspection result of each noise sensor is qualified, an amplitude calibration curve is generated based on multiple sets of corresponding measured amplitudes and reference amplitudes. The amplitude calibration curve is used to calibrate the measured amplitude of the noise sensor after it leaves the factory.
[0074] In this embodiment, taking any noise sensor with a qualified test result as an example, during the calibration process, the measured amplitude and reference amplitude of each group are first obtained, and then the amplitude calibration curve is calculated using the least squares method.
[0075] Optionally, the expression for the amplitude calibration curve is: Pz = k×Pre + h Where Pz is the calibrated amplitude and Pre is the measured amplitude; k and h are the parameters of the amplitude calibration curve, k is the calibration slope, which characterizes the degree of distortion of the noise sensor, and h is the drift compensation amplitude, which characterizes the degree of drift of the noise sensor; generally, the larger k is, the more serious the distortion problem of the response curve, and the larger h is, the more serious the drift problem.
[0076] In practical applications of noise sensors, in addition to calibrating their measured amplitude, noise sensors can also predict their performance degradation trend, assess the time span during future use to maintain measurement accuracy, and set reasonable subsequent detection reminder nodes accordingly.
[0077] Therefore, please refer to again Figure 5 After step S106, the sensor inspection and calibration method provided in this application embodiment further includes step S107.
[0078] S107: Each noise sensor estimates its expected lifespan while maintaining accurate measurement based on the calibration slope, drift compensation amplitude, and a pre-stored aging trend database; it sets the expected re-inspection time based on the expected lifespan and prompts for re-inspection when the expected re-inspection time is reached.
[0079] In this embodiment, the aging trend database can be statistically summarized based on long-term operating data of similar sensors, including multiple expected lifespans and the calibration slope range and drift compensation amplitude range corresponding to each expected lifespan.
[0080] For example, such as Figure 6As shown, if k≤k1 and h≤h1, the accuracy guarantee lifespan is determined to be 2 years, and the expected lifespan is 2 years; if k1<k≤k2 and h1<h≤h2, the accuracy guarantee lifespan is determined to be 1 year, and the expected lifespan is 1 year; if k2<k≤k3 and h2<h≤h3, the accuracy guarantee lifespan is determined to be 6 months, and the expected lifespan is 6 months; if k>k3 and h>h3, then it is determined to be scrapped.
[0081] Subsequently, the noise sensor sets the expected re-inspection time based on the estimated expected lifespan and a preset safety margin rule (e.g., 5 days). Optionally, a certain percentage of time window (e.g., 10% to 20%) can be reserved as a warning period before the expected lifespan is reached to ensure that the re-inspection is completed before significant performance degradation. Once the noise sensor's built-in timing module detects that the current time has reached the expected re-inspection time, it triggers a prompt signal, sends a re-inspection notification to an external system via the communication interface, or reminds the user to perform the re-inspection operation locally by activating indicator lights, buzzers, etc.
[0082] To ensure accuracy, the spatial positioning of multiple noise sensors needs to be precisely adjusted during the inspection and calibration process to ensure that the relative position between each noise sensor and the sound-generating device meets the test consistency requirements.
[0083] Therefore, please refer to again Figure 5 Before step S101, the sensor inspection and calibration method provided in this application embodiment further includes steps S10A to S10B.
[0084] S10A, the controller responds to the start test command and triggers the rangefinder to measure the real-time distance between each noise sensor and the sound-generating device.
[0085] S10B, the controller receives the measurement results uploaded by the rangefinder and controls the moving device to adjust its position according to the measurement results until the real-time distance between each noise sensor and the sound-generating device is equal to the distance between the sound analysis device and the sound-generating device.
[0086] In this embodiment, after the controller receives the start inspection command, in addition to driving multiple noise sensors into the anechoic chamber, it also simultaneously triggers the rangefinder to perform distance measurement tasks. For example, the rangefinder measures the real-time distance between each noise sensor and the sound-generating device individually or simultaneously, and uploads the measurement results to the controller. Optionally, the rangefinder is a sensing device capable of non-contactly measuring the straight-line distance between two points, which can be achieved using laser ranging, ultrasonic ranging, or infrared ranging techniques.
[0087] The controller receives all distance data from the rangefinder and compares it with a preset target distance, which is the distance between the sound analysis device and the sound-generating device. This target distance is a fixed standard reference value representing the ideal sound field test position. Since the amplitude of sound waves attenuates with distance when propagating in air, the acoustic environments are only comparable when the distance between each noise sensor and the sound-generating device is equal to the distance between the sound analysis device and the sound-generating device.
[0088] Based on the measurement results uploaded by the rangefinder, the controller generates corresponding adjustment commands and sends them to the mobile device. The mobile device then drives each noise sensor to make fine adjustments to its displacement within the anechoic chamber, such as moving back and forth along the guide rail, until the real-time distance fed back by the rangefinder approaches and eventually equals the target distance.
[0089] It should be noted that, in addition to controlling the position of the moving device to automatically adjust the distance between each noise sensor and the sound-generating device to be equal to the distance between the sound analysis device and the sound-generating device, a specially designed moving track can also be used to ensure that when the moving device reaches the left limit, all the noise sensors under test are naturally in the same sound field position as the sound analysis device. In this way, without the need for real-time ranging and feedback adjustment, the distance between each noise sensor and the sound-generating device can be ensured to be consistent, thereby guaranteeing the uniformity of acoustic conditions and calibration accuracy during the calibration process.
[0090] To better understand, the embodiments of this application will be further described below through examples.
[0091] In this embodiment, the overall process of the sensor inspection and calibration method may include: The operator completes the installation of each noise sensor to be standardized at the loading and unloading station, and then clicks "start" on the human-machine interface of the controller. At this time, the sensor mounting base is in the loading and unloading station (such as the right limit switch). After receiving the manual click signal, the controller issues an opening command and the automatic door opens. The controller issues a forward command, and the mobile device enters the anechoic chamber and moves to the preset detection station (such as the left limit). The controller issues a closing command, and the automatic door closes. The controller issues a sound-emitting command for frequency band 1 and amplitude 1. The sound-emitting device sends a sound wave for frequency band 1 and amplitude 1. The sound analysis device collects and analyzes the sound wave and reports f1 and p11. The controller issues a sampling command and sends f1 and p11. Each noise sensor collects and analyzes the sound wave and records fz1, pz11, f1, and p11. The controller issues a sound-emitting command for frequency band 1 and amplitude 2. The sound-emitting device sends sound waves for frequency band 1 and amplitude 2. The sound analysis device collects and analyzes the sound waves and reports f1 and p12. The controller issues a sampling command and sends f1 and p12. Each noise sensor collects and analyzes the sound waves and records fz1, pz12, f1, and p12. The controller issues a sound-emitting command for frequency band 1 and amplitude 3. The sound-emitting device sends sound waves for frequency band 1 and amplitude 3. The sound analysis device collects and analyzes the sound waves and reports f1 and p13. The controller issues a sampling command and sends f1 and p13. Each noise sensor collects and analyzes the sound waves and records fz1, pz13, f1, and p13. ... The controller issues a sound-emitting command for frequency band 3 and amplitude 3. The sound-emitting device sends a sound wave for frequency band 3 and amplitude 3. The sound analysis device collects and analyzes the sound wave and reports f3 and p33. The controller issues a sampling command and sends f3 and p33. Each noise sensor collects and analyzes the sound wave and records fz3, pz33, f3, and p33. The controller issues a test command, each noise sensor runs a test calibration program to obtain test results (pass / fail) and reports them. At the same time, when the test result is pass, an amplitude calibration curve is generated. The controller issues an opening command, and the automatic door opens. The controller issues a forward command, and the mobile device exits the anechoic chamber and retreats to the loading and unloading station (such as the right limit switch). The controller issues a closing command, and the automatic door closes. The controller displays the test results for each noise sensor; Operators sort good and bad products according to the inspection results. Unqualified noise sensors are collected and re-inspected. Those that pass the re-inspection are put into the good product warehouse, and those that still fail are put into the bad product warehouse.
[0092] Compared with the prior art, the embodiments of this application have the following beneficial effects: First, the sensor mounting base can install multiple noise sensors at the same time, enabling simultaneous testing and improving work efficiency. In addition, the base supports quick replacement and is compatible with noise sensors of different structures and appearances, making it highly versatile.
[0093] Secondly, it supports combined testing of multiple frequency bands and multiple amplitudes, covering a large range, and meeting the calibration needs under different acoustic environments.
[0094] Third, the entire process is automated, requiring no manual intervention, thus avoiding discrepancies caused by human operation and improving calibration accuracy and consistency.
[0095] In summary, the sensor testing and calibration method and system provided in this application include a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are located in the anechoic chamber, which provides a test environment isolated from external noise. After the controller responds to the start testing command, it controls the moving device to drive multiple noise sensors into the anechoic chamber and drives the sound-generating device to emit sound waves of different frequency bands and amplitudes in sequence, realizing dynamic calibration of the sensors over a wide range and under multiple operating conditions. After each sound wave is emitted, the sound analysis device collects reference acoustic features and uploads them to the controller, which then sends them to each noise sensor. At the same time, each noise sensor is triggered to collect measured acoustic features to ensure that the sampling is synchronized and consistent with the conditions. Each noise sensor autonomously judges whether it is qualified based on the reference features and the measured acoustic features and reports the results. The entire process is completed automatically without manual intervention, solving the problems of existing technologies that rely on manual operation, are inefficient, and can only calibrate one sensor at a time. This achieves efficient and accurate batch calibration of multiple sensors.
[0096] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A sensor testing and calibration method, characterized in that, This invention is applied to a sensor testing and calibration system, which includes a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are located in the anechoic chamber. The moving device can drive multiple noise sensors into or out of the anechoic chamber. The anechoic chamber is used to provide a test environment that isolates external noise. The sensor testing and calibration method includes: The controller responds to the start test command and controls the mobile device to bring multiple noise sensors into the anechoic chamber. The controller controls the sound-generating device to sequentially emit multiple sound waves of different frequency bands and amplitudes; The acoustic analysis device acquires the reference acoustic characteristics of the current sound wave and uploads the reference acoustic characteristics to the controller; The controller sends the reference acoustic features to each of the noise sensors and simultaneously triggers each of the noise sensors to collect the measured acoustic features of the current sound wave. Each noise sensor checks its own compliance based on the multiple measured acoustic features it collects and the multiple reference acoustic features it receives, obtains the test results, and reports them to the controller.
2. The sensor testing and calibration method as described in claim 1, characterized in that, The measured acoustic features include measured frequency and measured amplitude, and the reference acoustic features include reference frequency and reference amplitude; Each noise sensor verifies its own compliance based on multiple measured acoustic features it has acquired and multiple received reference acoustic features, including the following steps: Calculate the frequency deviation between the measured frequency and the reference frequency for each group, and determine whether the frequency deviation is within a first preset range; Calculate the amplitude deviation between the measured amplitude and the reference amplitude for each group, and determine whether the amplitude deviation is within the second preset range; If any of the frequency deviations exceeds the first preset range or any of the amplitude deviations exceeds the second preset range, the noise sensor is deemed unqualified; otherwise, the noise sensor is deemed qualified.
3. The sensor testing and calibration method as described in claim 1, characterized in that, The measured acoustic features include measured amplitudes, and the reference acoustic features include reference amplitudes; The sensor testing and calibration method further includes: If the inspection result is qualified, each noise sensor generates an amplitude calibration curve based on multiple sets of corresponding measured amplitudes and reference amplitudes. The amplitude calibration curve is used to calibrate the measured amplitude of the noise sensor after it leaves the factory.
4. The sensor testing and calibration method as described in claim 3, characterized in that, The parameters of the amplitude calibration curve include the calibration slope and the drift compensation amplitude. The calibration slope characterizes the degree of distortion of the noise sensor, and the drift compensation amplitude characterizes the degree of drift of the noise sensor. The sensor testing and calibration method further includes: Each noise sensor estimates its expected lifespan while maintaining measurement accuracy based on the calibration slope, the drift compensation amplitude, and a pre-stored aging trend database; it sets an expected re-inspection time based on the expected lifespan and prompts for re-inspection when the expected re-inspection time is reached.
5. The sensor testing and calibration method as described in claim 1, characterized in that, The sensor testing and calibration system also includes a rangefinder, which is mounted on the sound-generating device; The sensor testing and calibration method further includes: The controller responds to the start inspection command and triggers the rangefinder to measure the real-time distance between each noise sensor and the sound-generating device; The controller receives the measurement results uploaded by the rangefinder and controls the mobile device to adjust its position according to the measurement results until the real-time distance between each noise sensor and the sound-generating device is equal to the distance between the sound analysis device and the sound-generating device.
6. A sensor testing and calibration system, characterized in that, The sensor testing and calibration system includes a controller, an anechoic chamber, a moving device, a sound-generating device, a sound analysis device, and multiple noise sensors to be calibrated. The sound-generating device and the sound analysis device are located in the anechoic chamber, and the moving device can drive the multiple noise sensors into or out of the anechoic chamber. The anechoic chamber is used to provide a testing environment that isolates external noise; The controller is used to: respond to a start inspection command, control the mobile device to drive multiple noise sensors into the anechoic chamber; and control the sound-generating device to sequentially emit multiple sound waves of different frequency bands and amplitudes. The acoustic analysis device is used to collect reference acoustic features of the current sound wave and upload the reference acoustic features to the controller; The controller is also used to send the reference acoustic features to each of the noise sensors, and at the same time trigger each of the noise sensors to collect the measured acoustic features of the current sound wave; Each noise sensor is used to check whether it is qualified based on the multiple measured acoustic features it has collected and the multiple reference acoustic features it has received, and to obtain the test result and report it to the controller.
7. The sensor testing and calibration system as described in claim 6, characterized in that, The mobile device includes a support frame, a moving track, a moving control mechanism, and a sensor mounting base; The moving track is laid on the support and passes through the entrance of the anechoic chamber; The sensor mounting base is detachably mounted on the mobile control mechanism for simultaneously mounting multiple noise sensors to be calibrated. Different sensor mounting bases are adapted to different models of noise sensors.
8. The sensor testing and calibration system as described in claim 7, characterized in that, The mobile device also includes an adjustable switching power supply for powering the noise sensor on the sensor mounting base; The sensor testing and calibration system also includes a camera, which is located outside the anechoic chamber and faces the sensor mounting base, for capturing images of the installed noise sensor. The controller is also configured to: receive the image and identify the sensor model information in the image; query a pre-established Enterprise Resource Planning (ERP) system based on the model information to obtain the electrical information corresponding to the model information; and control the adjustable switching power supply to output a DC voltage that matches the electrical information.
9. The sensor testing and calibration system as described in claim 8, characterized in that, The moving track has a hollow structure and a power supply reel is installed inside. The power supply reel is connected to an external power source. The moving control mechanism is connected to the power supply reel via a first cable. The sensor mounting base is provided with multiple second cables, and each noise sensor mounted on the sensor mounting base is connected to the adjustable switching power supply through the corresponding second cable.
10. The sensor testing and calibration system as described in claim 6, characterized in that, The anechoic chamber is equipped with an automatic door, which is a double-leaf structure and has a flexible sealing material on the edge of the door. The controller is also configured to: respond to the start inspection command, open the automatic door, control the mobile device to drive multiple noise sensors into the anechoic chamber, and close the automatic door to isolate external noise after confirming that the mobile device has reached the preset inspection station.