Laser gyroscope longitudinal mode point scanning method

Abstract

The invention discloses a laser gyroscope longitudinal mode point scanning method, which relates to the technical field of laser inertial navigation, and comprises the following steps: setting a scanning range, a scanning step, a first threshold value and a second threshold value of a frequency stabilization driving voltage; outputting a frequency stabilization driving voltage according to the scanning step, and synchronously acquiring a corresponding direct current light intensity signal value; when the frequency stabilization driving voltage is greater than the lower boundary voltage, updating the current direct current light intensity minimum value and the corresponding first frequency stabilization driving voltage, and updating the current direct current light intensity maximum value and the corresponding second frequency stabilization driving voltage in real time; judging whether the currently output frequency stabilization driving voltage is greater than the sum of the first frequency stabilization driving voltage and a first threshold value or not; the voltage is greater than the sum of the second frequency stabilization driving voltage and a second threshold value; and when judging that the current direct-current light intensity minimum value and the first frequency stabilization driving voltage are simultaneously met, storing the current direct-current light intensity minimum value and the first frequency stabilization driving voltage as an effective longitudinal mode point, and adding 1 to the number of a longitudinal mode point counter.

Description

Technical Field

[0001] This invention relates to the field of laser inertial navigation technology, and more particularly to a laser gyroscope longitudinal mode point scanning method. Background Technology

[0002] As a core component of inertial navigation systems, the performance of laser gyroscopes directly determines navigation accuracy. Frequency stabilization technology is crucial for ensuring high-precision operation of laser gyroscopes; its core lies in accurately and quickly identifying the longitudinal mode point of the resonant cavity and locking the operating point at the optimal longitudinal mode center.

[0003] Currently, traditional laser gyroscope longitudinal mode identification methods mostly employ piezoelectric ceramic-based scanning frequency stabilization schemes. The typical process involves applying a sawtooth or triangular wave scanning voltage to the frequency stabilization driving voltage of the resonant cavity, causing periodic changes in the cavity length, while simultaneously detecting the transmitted or reflected DC light intensity signal. Within a complete scanning cycle, the light intensity exhibits a series of maxima and minima, with the minima typically corresponding to the longitudinal mode point of the resonant cavity. Existing technologies suffer from the following inherent drawbacks: their fixed scanning parameters lead to a trade-off between scanning efficiency and accuracy, making it difficult to achieve both; they exhibit poor anti-interference capabilities in complex noise environments, easily causing misidentification and missed identification of longitudinal mode points; furthermore, the methods lack intelligence and adaptability, failing to adapt to changes in individual gyroscopes and their operating states; and they lack effective verification of the risk of misidentification of the first longitudinal mode point at the start of the scan, potentially leading to errors in the entire frequency stabilization sequence. These problems collectively constrain the accuracy, reliability, and rapid start-up capability of laser gyroscope frequency stabilization systems.

[0004] Therefore, there is an urgent need in this field for a laser gyroscope longitudinal mode point scanning method that can balance high precision, high efficiency, and high reliability, and also has a certain degree of adaptability. Summary of the Invention

[0005] This application provides a laser gyroscope longitudinal mode point scanning method, which solves the problems in the prior art such as difficulty in balancing scanning efficiency and accuracy, poor anti-interference ability leading to misjudgment and missed judgment of longitudinal mode points, and lack of adaptive ability, and achieves high-precision, high-efficiency and high-reliability longitudinal mode point recognition.

[0006] This application provides a laser gyroscope longitudinal mode point scanning method, including:

[0007] S1: Set the scanning range, scanning step, first threshold value, and second threshold value of the frequency stabilization drive voltage; initialize the extreme value buffer variable and the longitudinal modulus counter;

[0008] S2: Within the scanning range, output the frequency-stabilized driving voltage according to the scanning step, and synchronously collect the corresponding DC light intensity signal value; when the frequency-stabilized driving voltage is greater than the lower boundary voltage, update the current DC light intensity minimum value and its corresponding first frequency-stabilized driving voltage, and the current DC light intensity maximum value and its corresponding second frequency-stabilized driving voltage in real time.

[0009] S3: Determine whether the current output frequency-stabilized driving voltage simultaneously satisfies: greater than the sum of the first frequency-stabilized driving voltage and the first threshold value; greater than the sum of the second frequency-stabilized driving voltage and the second threshold value; when the judgment is satisfied simultaneously, save the current DC light intensity minimum value and the first frequency-stabilized driving voltage as an effective longitudinal mode point, reset the extreme value cache variable, and increment the longitudinal mode point counter by 1;

[0010] S4: When the frequency stabilization driving voltage is less than the upper boundary voltage, repeat steps S2 to S3 until the frequency stabilization driving voltage reaches the upper boundary voltage of the scanning range.

[0011] Furthermore, the scanning range includes the lower boundary voltage and the upper boundary voltage;

[0012] The lower boundary voltage is used as the threshold to determine whether to start updating the extreme value cache variable;

[0013] The upper boundary voltage is used as a condition to determine whether to terminate the scanning cycle.

[0014] Furthermore, the initialization includes: setting the number of longitudinal mode points to 0, resetting the DC light intensity minimum value cache value and the DC light intensity maximum value cache value, clearing the saved longitudinal mode point data, and setting the frequency stabilization drive voltage to the scan start value.

[0015] Further, after the longitudinal mode point is saved, the following steps are taken: when the number of longitudinal mode points is 1, it is determined whether the current DC light intensity minimum value cache value used for saving is less than the DC light intensity value of the first saved longitudinal mode point minus the third threshold value; if the condition is met, the first longitudinal mode point is determined to be invalid, the number of longitudinal mode points is reset to 0, and the extreme value cache variable is reset; so that the next identified valid longitudinal mode point will overwrite the first longitudinal mode point that was originally saved.

[0016] Furthermore, after incrementing the longitudinal modulus counter by 1, the method further includes: determining whether the current number of longitudinal modulus points exceeds a preset upper limit of 15; if it does, resetting the longitudinal modulus counter to 0 and clearing the saved longitudinal modulus data.

[0017] Furthermore, the specific values ​​of the first threshold, the second threshold, and the third threshold are determined based on a comprehensive analysis and optimization of measured data from different types of laser gyroscopes;

[0018] The first threshold value is used to ensure that the current frequency-stabilized drive voltage has moved far away from the recorded minimum value of DC light intensity, so as to avoid misjudgment caused by noise interference;

[0019] The second threshold value is used to ensure that the current frequency-stabilized drive voltage has moved away from the recorded maximum DC light intensity point, so as to ensure that there is a sufficient span of light intensity variation between the identified longitudinal mode points;

[0020] The third threshold value is used to determine whether the longitudinal modulus point is a valid starting longitudinal modulus point when it is first identified.

[0021] Furthermore, the initialization also includes: during the initialization phase, loading historical scanning data of the same model of laser gyroscope, including the voltage position distribution of historical longitudinal mode points, the corresponding light intensity characteristic mode and scanning environment parameters; establishing a probability distribution model of longitudinal mode point occurrence based on historical data, and dividing the scanning voltage range into high probability interval, medium probability interval and low probability interval;

[0022] During scanning, different scanning strategies are adopted according to different probability ranges: fine scanning with standard scanning steps is used in high probability ranges; fast scanning with larger scanning steps is used in medium probability ranges, and automatic switching back to standard steps is used when abnormal fluctuations in light intensity are detected; and fast scanning with the maximum scanning step is used in low probability ranges, with only basic signal acquisition performed.

[0023] Furthermore, the scanning process also includes: comparing the degree of conformity between the identified longitudinal modulus point positions and the prediction model in real time during the scanning process; automatically switching to full-range fine scanning mode when the deviation between the identification result and the prediction model exceeds a preset threshold; and updating the actual longitudinal modulus point distribution and scanning effect evaluation data of this scan to the historical database after the scan is completed, in order to optimize the prediction model for subsequent scans.

[0024] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0025] By employing a dual-threshold criterion confirmation mechanism, dynamic verification of the first point, and an adaptive partitioning scanning strategy based on historical data, the shortcomings of traditional methods in terms of accuracy, efficiency, and anti-interference ability are addressed. This enables rapid, accurate, and reliable identification of longitudinal modulus points and provides self-learning optimization capabilities to adapt to different individuals and work conditions. Attached Figure Description

[0026] Figure 1 This is a flowchart of a laser gyroscope longitudinal mode point scanning method according to an embodiment of the present invention. Detailed Implementation

[0027] To facilitate understanding of the present invention, a more complete description of this application will be given below with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to enable a more thorough and complete understanding of the disclosure of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] Example 1: As Figure 1 As shown, a laser gyroscope longitudinal mode point scanning method is described.

[0030] S1: Set the scanning range, scanning step, first threshold value, and second threshold value of the frequency stabilization drive voltage; initialize the extreme value buffer variable and the longitudinal modulus counter;

[0031] The scanning range includes the lower boundary voltage and the upper boundary voltage;

[0032] The lower boundary voltage is used as the threshold to determine whether to start updating the extreme value cache variable;

[0033] The upper boundary voltage is used as a condition to determine whether to terminate the scanning cycle.

[0034] Specifically, the lower boundary voltage is set to a value slightly higher than the scan start voltage, serving as the logic threshold for initiating extreme value tracking to avoid interference from transient processes during system startup on longitudinal mode point identification. The upper boundary voltage is set as the target termination voltage for the scan process, serving as the condition for determining whether the scan cycle has ended. The scan step size is selected based on the system's overall requirements for scan accuracy and efficiency; the standard scan step size is typically set to 0.1V to ensure precise detection of longitudinal mode points. When performing differentiated scans based on historical probability models, this step size can be dynamically adjusted according to the probability levels of different intervals.

[0035] The first threshold value is used to ensure that the current frequency-stabilized drive voltage has moved far away from the recorded minimum value of DC light intensity, so as to avoid misjudgment caused by noise interference;

[0036] Specifically, the first threshold value is determined based on statistical analysis of a large amount of experimental data. Its value must ensure that after identifying a minimum light intensity value, the scanning voltage must exceed the difference between the voltage corresponding to that longitudinal mode point and at least the first threshold value before the system allows the confirmation of the next potential longitudinal mode point. This mechanism can effectively prevent duplicate recording or misjudgment caused by signal fluctuations or noise near the same longitudinal mode point.

[0037] The second threshold value is used to ensure that the current frequency-stabilized drive voltage has moved away from the recorded maximum DC light intensity point, so as to ensure that there is a sufficient span of light intensity variation between the identified longitudinal mode points;

[0038] Specifically, the second threshold value is optimized and determined based on experimental data. Its value must ensure that after the scanning voltage exceeds a maximum light intensity value, it must exceed the difference between the voltage corresponding to that maximum value and at least the second threshold value before the system can make final confirmation of the longitudinal mode point. This ensures that there is a complete and significant light intensity change cycle between adjacent identified longitudinal mode points, thereby effectively distinguishing different longitudinal modes physically.

[0039] The initialization includes: setting the number of longitudinal mode points to 0, resetting the DC light intensity minimum value cache value and the DC light intensity maximum value cache value, clearing the saved longitudinal mode point data, and setting the frequency stabilization drive voltage to the scan start value.

[0040] Specifically, the longitudinal mode point counter is cleared to zero, and the DC light intensity minimum value cache variable is initialized to a theoretical maximum value much larger than the expected light intensity signal to ensure that the first light intensity value encountered during the scanning process can update this cache normally. The DC light intensity maximum value cache variable is initialized to a theoretical minimum value much smaller than the expected light intensity signal to ensure that the first light intensity value can update this cache normally. The first and second frequency-stabilized drive voltage cache variables that record the extreme point voltages are reset. The data list or array used to store the identified longitudinal mode point information is cleared; the frequency-stabilized drive voltage output by the system is set to the starting voltage value of this scan.

[0041] S2: Within the scanning range, output the frequency-stabilized driving voltage according to the scanning step, and synchronously collect the corresponding DC light intensity signal value; when the frequency-stabilized driving voltage is greater than the lower boundary voltage, update the current DC light intensity minimum value and its corresponding first frequency-stabilized driving voltage, and the current DC light intensity maximum value and its corresponding second frequency-stabilized driving voltage in real time.

[0042] Specifically, the frequency-stabilized driving voltage is cyclically increased using a preset scanning step as the increment. After each new frequency-stabilized driving voltage is output, the system synchronously acquires the DC light intensity signal value output by the laser gyroscope at that time. This process continues, causing the frequency-stabilized driving voltage to increase linearly from the starting voltage until it reaches the upper boundary voltage.

[0043] After each voltage output and light intensity acquisition, the system checks whether the precondition for extreme value update is met: whether the current frequency-stabilized drive voltage is greater than the lower boundary voltage. If the current voltage is less than or equal to the lower boundary voltage, only voltage output and light intensity acquisition are performed, and the extreme value update operation is not executed. If the current voltage is greater than the lower boundary voltage, it is determined that the valid scanning range has been entered, and the extreme value detection and update logic is activated.

[0044] The currently acquired light intensity value is compared with the current minimum DC light intensity value in the cache. If the current light intensity value is less than the cached minimum light intensity value, it indicates that a smaller light intensity value has been encountered. The cached minimum light intensity value is updated to the current light intensity value, and the variable recording the voltage corresponding to this minimum value, the first frequency-stabilized driving voltage, is updated to the current voltage value. Otherwise, the cached minimum light intensity value and its corresponding voltage remain unchanged.

[0045] The currently acquired light intensity value is compared with the current maximum DC light intensity value in the cache. If the current light intensity value is greater than the cached maximum light intensity value, it indicates that a larger light intensity value has been encountered. The cached maximum light intensity value is updated to the current light intensity value, and the variable corresponding to the voltage of this maximum value, the second frequency-stabilized driving voltage, is updated to the current voltage value. Otherwise, the cached maximum light intensity value and its corresponding voltage remain unchanged.

[0046] S3: Determine whether the current output frequency-stabilized driving voltage simultaneously satisfies: greater than the sum of the first frequency-stabilized driving voltage and the first threshold value; greater than the sum of the second frequency-stabilized driving voltage and the second threshold value; when the judgment is satisfied simultaneously, save the current DC light intensity minimum value and the first frequency-stabilized driving voltage as an effective longitudinal mode point, reset the extreme value cache variable, and increment the longitudinal mode point counter by 1;

[0047] Specifically, after each voltage step, light intensity acquisition, and extreme value cache update, the system immediately enters the longitudinal mode point confirmation and judgment stage. This judgment is based on a dual-threshold criterion, and the following two conditions must be met simultaneously to recognize the currently cached light intensity minimum as a valid longitudinal mode point. Condition 1: The current frequency-stabilized driving voltage is greater than the sum of the first frequency-stabilized driving voltage and the first threshold value; ensuring that the system has moved far enough away from the previously recorded light intensity minimum. This condition effectively prevents the system from making repeated judgments and making erroneous records near the same longitudinal mode point due to signal noise or local fluctuations, thus ensuring the uniqueness of each longitudinal mode point being identified and recorded. Condition 2: The current frequency-stabilized driving voltage is greater than the sum of the second frequency-stabilized driving voltage and the second threshold value; ensuring that after identifying a light intensity minimum, the system has not only moved far away from that minimum point but has also crossed and moved far away from the immediately following light intensity maximum point. This condition ensures that before confirming the longitudinal mode point, the light intensity signal has experienced a complete decreasing-increasing-decreasing trend, exhibiting significant light intensity change periodic characteristics. This physically verifies that the minimum point is a real resonant cavity longitudinal mode, rather than a non-periodic random noise interference, thus ensuring the accuracy of the identification.

[0048] If and only if both conditions are met simultaneously, the minimum DC light intensity value in the current extreme value cache (i.e., the longitudinal mode point light intensity value that has been verified by the criterion) and its corresponding first stable frequency driving voltage (i.e., the precise voltage position of the longitudinal mode point) are written as a data pair into the list of identified longitudinal mode points for permanent storage.

[0049] The system resets and initializes the cached variables used for tracking extreme values. The current DC light intensity minimum variable is reset to a theoretical maximum value (e.g., 5V) much larger than the expected light intensity signal, while the current DC light intensity maximum variable is reset to a theoretical minimum value (e.g., 0V) much smaller than the expected light intensity signal. The corresponding first and second frequency-stabilized drive voltage recording variables are cleared to zero. The longitudinal mode counter is incremented by 1, and the total number of valid longitudinal mode points successfully identified in this scan is counted.

[0050] After the longitudinal modulus point is saved, the following steps are taken: when the number of longitudinal modulus points is 1, it is determined whether the current DC light intensity minimum value cache value used for saving is less than the DC light intensity value of the first saved longitudinal modulus point minus the third threshold value; if the condition is met, the first longitudinal modulus point is determined to be invalid, the number of longitudinal modulus points is reset to 0, and the extreme value cache variable is reset; so that the next identified valid longitudinal modulus point will overwrite the first longitudinal modulus point that was originally saved.

[0051] Specifically, to avoid misidentification during the initial scanning phase due to incomplete laser output stabilization, signal transients, or local noise interference, a dynamic verification mechanism is incorporated. A true and valid longitudinal mode point should have a significantly lower intensity and noise level than its surrounding background. If the first identified longitudinal mode point is genuine, then in subsequent scans, the minimum intensity of newly emerging candidate longitudinal mode points should not be significantly lower than the intensity of the first point. Conversely, if the intensity of a new point is much lower than that of the first point, it strongly suggests that the first point may not be a true resonance valley value, but rather located in an unstable region or a spurious minimum value generated by noise.

[0052] The third threshold value is used to determine whether the longitudinal modulus point is a valid starting longitudinal modulus point when it is first identified.

[0053] Specifically, the third threshold is a light intensity difference threshold. Its specific value is determined through statistical analysis and optimization of a large amount of historical measured data from the same model of laser gyroscope. Under stable operating conditions, the effective longitudinal mode point light intensity data of this model of gyroscope is collected multiple times, and the light intensity difference between the first truly effective longitudinal mode point and the subsequent second and third longitudinal mode points is recorded. The distribution of these effective light intensity differences is calculated, and the normal fluctuation range is observed. The third threshold is set to a value slightly larger than the normal fluctuation range. This value needs to be large enough to reliably distinguish between abnormally large light intensity differences caused by an invalid starting point and small light intensity fluctuations between normal longitudinal mode points.

[0054] Determine if the current DC intensity minimum cache value used for storage is less than the DC intensity value of the first saved longitudinal mode point minus the third threshold value. If the condition is met, i.e., the intensity value of the new candidate longitudinal mode point is much lower than the intensity value of the first point (the difference exceeds the third threshold value), then the first longitudinal mode point is determined to be invalid. Reset the number of longitudinal mode points to 0, and restore the current DC intensity minimum, maximum, and corresponding voltage cache variables to their initial state.

[0055] After incrementing the longitudinal modulus counter by 1, the method further includes: determining whether the current number of longitudinal modulus points exceeds a preset upper limit of 15. If it does, the longitudinal modulus counter is reset to 0, and the saved longitudinal modulus data is cleared.

[0056] Specifically, the upper limit of 15 is determined based on statistical analysis of the maximum possible number of longitudinal modes for various laser gyroscope products within the maximum permissible scanning voltage range. This value is set to be much larger than the number of longitudinal mode points that may occur under any normal operating conditions, thus ensuring that the counter will never trigger this upper limit in the vast majority of normal scans. It is both large enough to avoid false alarms caused by individual noise points or special operating conditions, and small enough to be quickly triggered when a real anomaly or system malfunction occurs, preventing the impact of the anomaly from escalating. Setting a reasonable upper limit of 15 is mainly used to detect and handle logical disorder or infinite loops caused by severe interference to the system. The purpose is to promptly interrupt the erroneous scanning process when such anomalies are detected, restoring the system to a known clean initial state.

[0057] After each successful saving of a longitudinal modulus point, the longitudinal modulus point counter increments by 1. The system then checks if the current number of longitudinal modulus points exceeds a preset upper limit of 15. If it does not exceed 15, the current scan is considered normal, and subsequent scan cycles continue. If it exceeds 15, a serious anomaly is detected in the scan process, and a valid longitudinal modulus point sequence cannot be obtained. The longitudinal modulus point counter is then reset to 0, and the saved longitudinal modulus point data is cleared.

[0058] S4: When the frequency stabilization driving voltage is less than the upper boundary voltage, repeat steps S2 to S3 until the frequency stabilization driving voltage reaches the upper boundary voltage of the scanning range.

[0059] Specifically, after successfully executing step S3, the system does not terminate immediately but instead performs a loop condition check. It checks whether the currently output stable frequency drive voltage value is less than a preset upper boundary voltage value. As long as the condition is met, steps S2 to S3 are repeated, and the loop continues, with the stable frequency drive voltage gradually increasing. When the system detects that the current stable frequency drive voltage value has reached or exceeded the upper boundary voltage value, the scanning loop terminates immediately. At this point, the system has typically identified and saved a series of valid longitudinal mode points.

[0060] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0061] This application effectively overcomes the shortcomings of traditional methods, which are susceptible to interference and prone to misjudgment and omission in complex noise environments, by introducing a longitudinal mode point confirmation mechanism based on dual threshold criteria. Utilizing dual verification of voltage distance and light intensity variation span, the uniqueness and physical authenticity of each identified longitudinal mode point are ensured, thus significantly improving the accuracy of identification. By designing a dynamic first-point verification mechanism, the first longitudinal mode point identified in the initial scanning phase is verified with a delay, effectively filtering out invalid starting points caused by transient or local noise during system startup, fundamentally avoiding systematic deviations in the entire frequency stabilization sequence and enhancing the reliability of the method. By integrating an adaptive partitioned scanning strategy based on historical data, the scanning step is dynamically adjusted according to the probability of longitudinal mode points appearing in different voltage ranges, achieving fine scanning in critical areas and rapid passage through non-critical areas, successfully resolving the contradiction between scanning efficiency and accuracy. Through a built-in longitudinal mode point quantity limit check and automatic reset mechanism, the system is provided with effective self-fault tolerance and recovery capabilities under extreme abnormal conditions, further improving overall robustness.

[0062] Example 2: Example 1 achieved highly reliable identification, but it still has shortcomings such as a fixed scanning strategy and inability to adapt to individual differences. This example further supplements Example 1.

[0063] The initialization also includes: during the initialization phase, loading historical scanning data of the same model of laser gyroscope, including the voltage position distribution of historical longitudinal mode points, the corresponding light intensity characteristic mode and scanning environment parameters; establishing a probability distribution model of longitudinal mode point occurrence based on historical data, and dividing the scanning voltage range into high probability interval, medium probability interval and low probability interval;

[0064] Specifically, the scanning data accumulated from multiple normal operations of the same model of laser gyroscope is loaded, including: recording the frequency-stabilized drive voltage value corresponding to each effective longitudinal mode point in each scan, forming a database of voltage positions of longitudinal mode points for this model of gyroscope; recording the minimum light intensity, adjacent maximum light intensity, and characteristic parameters of the light intensity variation curve at each longitudinal mode point; and recording key parameters that may affect the longitudinal mode position, such as ambient temperature and laser operating current during scanning.

[0065] Based on historical data, a statistical analysis method (Gaussian mixture model) was used to fit the voltage locations where longitudinal modulus points (LM points) appeared, establishing a probability distribution model for LM point occurrence. According to this probability distribution model, the entire voltage range to be scanned was dynamically divided into three intervals: The high-probability interval consists of one or more consecutive voltage segments with the highest probability values ​​in the probability distribution model; this interval represents the core area where historical data indicates the highest probability of finding LM points. The medium-probability interval consists of voltage segments with significantly lower probability values ​​than those in the high-probability interval; LM points are possible in this interval, but the probability is relatively low. The low-probability interval consists of voltage segments with probability values ​​close to zero or significantly lower than those in the medium-probability interval; historical data shows that effective LM points have rarely or never appeared in this region.

[0066] During scanning, different scanning strategies are adopted according to different probability ranges: fine scanning with standard scanning steps is used in high probability ranges; fast scanning with larger scanning steps is used in medium probability ranges, and automatic switching back to standard steps is used when abnormal fluctuations in light intensity are detected; and fast scanning with the maximum scanning step is used in low probability ranges, with only basic signal acquisition performed.

[0067] Specifically, in the high-probability range, a smaller standard scanning step (e.g., voltage increment = 0.1V) is used for scanning. This ensures that no potential longitudinal mode points are missed due to excessively fast scanning in the high-probability area, guaranteeing the highest recognition accuracy and detection rate. In the medium-probability range, to balance scanning efficiency, a larger scanning step (e.g., voltage increment = 0.3V) is used for rapid scanning to shorten the time spent traversing this area. Simultaneously, the system incorporates a light intensity anomaly fluctuation monitoring mechanism, calculating the rate of change or variance of the light intensity signal in real time. If a sudden increase in the rate of change of light intensity or a drastic fluctuation inconsistent with noise is detected, the system automatically determines that a longitudinal mode point or an anomaly may exist at that location that was not accurately predicted by the probability model. Once fluctuation monitoring is triggered, the system immediately switches the scanning step from a large step back to a standard step and performs a fine scan within a small range near the current voltage point to confirm or rule out the presence of longitudinal mode points. Within the low-probability range, the voltage is rapidly increased using a preset maximum scanning step (e.g., voltage increment = 0.5V) to traverse the region in the shortest time, saving overall scanning time. Only the most basic voltage output and light intensity signal acquisition and recording are performed, and the extreme value cache update logic and longitudinal mode point judgment logic are paused.

[0068] The scanning process also includes: comparing the degree of conformity between the identified longitudinal modulus point positions and the prediction model in real time during the scanning process; automatically switching to full-range fine scanning mode when the deviation between the identification result and the prediction model exceeds a preset threshold; and updating the actual longitudinal modulus point distribution and scanning effect evaluation data of this scan to the historical database after the scan is completed, so as to optimize the prediction model for subsequent scans.

[0069] Specifically, during the scanning process, whenever a longitudinal modulus point is successfully identified, the system calculates in real time the deviation between its key parameters, such as voltage position and light intensity characteristics, and the prediction model built based on historical data. Once the overall deviation exceeds a preset safety threshold based on the historical fluctuation range, the system determines that the reliability of the current optimized scanning strategy is insufficient. The system will then immediately and automatically terminate the differentiated scanning and switch to a full-range fine scanning mode using the minimum standard step size across the entire remaining voltage range. This is a safeguard to ensure the final success rate of the scan. After the scan is completely completed, the system will update the historical database with the actual distribution of identified longitudinal modulus points and the scanning effect evaluation data as new samples, and recalculate and optimize the probability distribution model based on the expanded data.

[0070] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0071] This application achieves intelligent partitioning of the scanning voltage range by loading historical scanning data from gyroscopes of the same model and establishing a probability distribution model of longitudinal mode point occurrence, thereby optimizing uniform scanning into targeted differentiated scanning. By employing fine scanning in the high-probability range to ensure recognition accuracy, combining rapid scanning with an automatic switching mechanism for abnormal fluctuations in the medium-probability range to balance efficiency and reliability, and using a fast-pass mode in the low-probability range to save time, the application successfully improves scanning efficiency while maintaining a high detection rate. By comparing the consistency between the recognition results and the prediction model in real time, and automatically switching to a full-range fine scanning mode when the deviation exceeds the limit, reliable fault tolerance is provided for the scanning process, ensuring the robustness of the method. By feeding the current scanning data back to the historical database and continuously optimizing the prediction model, the long-term applicability and intelligence level of the method are improved.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A laser gyroscope longitudinal mode point scanning method, characterized in that, include: S1: Set the scanning range, scanning step, first threshold value, and second threshold value of the frequency stabilization drive voltage; initialize the extreme value buffer variable and the longitudinal modulus counter; S2: Within the scanning range, output the frequency-stabilized driving voltage according to the scanning step, and synchronously collect the corresponding DC light intensity signal value; when the frequency-stabilized driving voltage is greater than the lower boundary voltage, update the current DC light intensity minimum value and its corresponding first frequency-stabilized driving voltage, and the current DC light intensity maximum value and its corresponding second frequency-stabilized driving voltage in real time. S3: Determine whether the current output frequency-stabilized driving voltage simultaneously satisfies: greater than the sum of the first frequency-stabilized driving voltage and the first threshold value; greater than the sum of the second frequency-stabilized driving voltage and the second threshold value; when the judgment is satisfied simultaneously, save the current DC light intensity minimum value and the first frequency-stabilized driving voltage as an effective longitudinal mode point, reset the extreme value cache variable, and increment the longitudinal mode point counter by 1; S4: When the frequency stabilization driving voltage is less than the upper boundary voltage, repeat steps S2 to S3 until the frequency stabilization driving voltage reaches the upper boundary voltage of the scanning range.

2. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, The scanning range includes the lower boundary voltage and the upper boundary voltage; The lower boundary voltage is used as the threshold to determine whether to start updating the extreme value cache variable; The upper boundary voltage is used as a condition to determine whether to terminate the scanning cycle.

3. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, The initialization includes: setting the number of longitudinal mode points to 0, resetting the DC light intensity minimum value cache value and the DC light intensity maximum value cache value, clearing the saved longitudinal mode point data, and setting the frequency stabilization drive voltage to the scan start value.

4. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, After the longitudinal modulus point is saved, the following steps are taken: when the number of longitudinal modulus points is 1, it is determined whether the current DC light intensity minimum value cache value used for saving is less than the DC light intensity value of the first saved longitudinal modulus point minus the third threshold value; if the condition is met, the first longitudinal modulus point is determined to be invalid, the number of longitudinal modulus points is reset to 0, and the extreme value cache variable is reset; so that the next identified valid longitudinal modulus point will overwrite the first longitudinal modulus point that was originally saved.

5. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, After incrementing the longitudinal modulus counter by 1, the method further includes: determining whether the current number of longitudinal modulus points exceeds a preset upper limit of 15. If it does, the longitudinal modulus counter is reset to 0, and the saved longitudinal modulus data is cleared.

6. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, The specific values ​​of the first threshold, the second threshold, and the third threshold are determined based on a comprehensive analysis and optimization of measured data from different types of laser gyroscopes. The first threshold value is used to ensure that the current frequency-stabilized drive voltage has moved far away from the recorded minimum value of DC light intensity, so as to avoid misjudgment caused by noise interference; The second threshold value is used to ensure that the current frequency-stabilized drive voltage has moved away from the recorded maximum DC light intensity point, so as to ensure that there is a sufficient span of light intensity variation between the identified longitudinal mode points; The third threshold value is used to determine whether the longitudinal modulus point is a valid starting longitudinal modulus point when it is first identified.

7. The laser gyroscope longitudinal mode point scanning method as described in claim 1, characterized in that, The initialization also includes: during the initialization phase, loading historical scanning data of the same model of laser gyroscope, including the voltage position distribution of historical longitudinal mode points, the corresponding light intensity characteristic mode and scanning environment parameters; establishing a probability distribution model of longitudinal mode point occurrence based on historical data, and dividing the scanning voltage range into high probability interval, medium probability interval and low probability interval; During scanning, different scanning strategies are adopted according to different probability ranges: fine scanning with standard scanning steps is used in high probability ranges; fast scanning with larger scanning steps is used in medium probability ranges, and automatic switching back to standard steps is used when abnormal fluctuations in light intensity are detected; and fast scanning with the maximum scanning step is used in low probability ranges, with only basic signal acquisition performed.

8. The laser gyroscope longitudinal mode point scanning method as described in claim 7, characterized in that, The scanning process also includes: comparing the degree of conformity between the identified longitudinal modulus point positions and the prediction model in real time during the scanning process; automatically switching to full-range fine scanning mode when the deviation between the identification result and the prediction model exceeds a preset threshold; and updating the actual longitudinal modulus point distribution and scanning effect evaluation data of this scan to the historical database after the scan is completed, so as to optimize the prediction model for subsequent scans.

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