A frequency point temperature self-adaptive control system and method of a resonant scanning mirror

Abstract

The application discloses a kind of frequency point temperature self-adaptive control system and method of resonant scanning mirror, the method includes: step S1: setting the initial frequency and initial amplitude of the resonant scanning mirror;Step S2: sampling the PSD position feedback signal of resonant scanning mirror angle and filtering;Step S3: enter the initialization search module;Step S4: the amplitude of the resonant scanning mirror is adjusted to target value by the amplitude modulation module;Step S5: the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module, to realize the frequency point temperature self-adaptive control of the resonant scanning mirror.The application can control the scanning angle of resonant mirror to be stable around an angle, and through the adaptive adjustment of frequency and amplitude, the resonant scanning mirror can resist the influence brought by temperature change, to finally ensure that laser radar scanning mirror adapts to different temperature conditions, and realizes stable driving.

Description

Technical Field

[0001] This invention relates to the field of resonant mirror control methods, specifically to a frequency-temperature adaptive control system and method for a resonant scanning mirror. Background Technology

[0002] Resonant scanning mirror lidar is an important technological approach in lidar solutions. Resonant scanning mirrors offer advantages such as large scanning angle, low power consumption, low inertia, small size, light weight, and easy integration, making them widely used in lidar systems and micro-opto-electro-mechanical systems. Compared to traditional projection imaging, resonant scanning mirrors can be used not only to scan by emitting and reflecting laser pulses, but also to receive and reflect the echo signals of laser pulses.

[0003] The frequency of a resonant scanning mirror changes significantly with temperature. As the temperature rises or falls, the mirror becomes unstable to some extent, and it can no longer function normally at the current resonant frequency. The mirror then experiences misalignment and no longer operates at its current angle. Existing control methods for resonant scanning mirrors lack a technical solution to address the resonant frequency drift caused by temperature changes. Summary of the Invention

[0004] The purpose of this invention is to provide a frequency-temperature adaptive control system and method for a resonant scanning mirror. This aims to solve the problem in existing technologies where there is no temperature-based frequency control for resonant scanning mirrors, causing them to malfunction.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: On one hand, the present invention provides a frequency-temperature adaptive control system for a resonant scanning mirror, comprising: A resonant scanning mirror drive module, which is connected to the resonant scanning mirror and is used to drive the resonant scanning mirror; A position-sensitive detector is disposed on one side of the resonant scanning mirror to obtain the angle of the resonant scanning mirror; An initialization search module is established, which is connected to the position-sensitive detector and the resonant scanning mirror respectively, to search for the resonant frequency point of the resonant scanning mirror by means of a fixed frequency step size; An amplitude modulation module, connected to the initialization search module, is used to adjust the amplitude of the resonant scanning mirror to the target value; A frequency modulation module, which is connected to the amplitude modulation module, is used to adaptively adjust the frequency of the resonant scanning mirror.

[0006] Preferably, the position-sensitive detector acquires the angle of the resonant scanning mirror and converts it into a position feedback signal.

[0007] Preferably, after completing the search for the resonant frequency point, the initialization search module sets the search flag and the adaptive amplitude modulation enable flag.

[0008] Preferably, adjusting the amplitude of the resonant scanning mirror to the target value specifically involves adjusting the amplitude of the resonant scanning mirror to the target value of the position-sensitive detector based on the difference between the current position feedback signal of the position-sensitive detector and the target value of the position-sensitive detector.

[0009] On the other hand, the present invention also provides a frequency-temperature adaptive control method for a resonant scanning mirror, wherein the above-mentioned frequency-temperature adaptive control system for a resonant scanning mirror includes: Step S1: Set the initial frequency and initial amplitude of the resonant scanning mirror using the resonant scanning mirror driving module; Step S2: Use a position-sensitive detector to acquire a position feedback signal about the angle of the resonant scanning mirror, and filter the position feedback signal to obtain a filtered position feedback signal; Step S3: Obtain the resonant frequency point through the initialization search module; Step S4: Based on the resonant frequency point, the amplitude modulation module adjusts the amplitude of the resonant scanning mirror to the target value; Step S5: Based on the resonant frequency point, the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module to achieve adaptive frequency-temperature control of the resonant scanning mirror.

[0010] Preferably, in step S3, the resonant frequency point is obtained through the initialization search module, which specifically includes: Step S3.1: Set the target value, amplitude step size, and frequency step size of the position-sensitive detector; Step S3.2: Set the initial values ​​of the frequency and amplitude of the resonant scanning mirror; Step S3.3: Sample the current position feedback signal of the position-sensitive detector; Step S3.4: At each frequency step, sample the current corresponding position feedback signal, repeat the above sampling several times, determine the maximum value among all the position feedback signals, and determine the frequency of the resonant scanning mirror corresponding to the maximum value among all the position feedback signals.

[0011] Preferably, in step S4, the amplitude modulation module adjusts the amplitude of the resonant scanning mirror to the target value, which specifically includes: Step S4.1: The amplitude modulation module performs a first time count. If the first time count is less than the amplitude period, the first time count is incremented by one. If the first time count is not less than the amplitude period, then proceed to step S4.2. The amplitude period is the amplitude change control period of the resonant scanning mirror. The specific setting value is determined based on different systems. Step S4.2: When the first time count reaches a preset threshold, the count is reset. When the position value of the resonant scanning mirror corresponding to the current position feedback signal is less than the target value of the position-sensitive detector, If the amplitude of the current resonant scanning mirror is less than the preset upper limit, then the amplitude of the current resonant scanning mirror is increased by one amplitude step, and the frequency modulation module enable flag is set. If the amplitude of the resonant scanning mirror is at the preset upper limit, then the frequency modulation module start flag is set. Step S4.3: The position value of the resonant scanning mirror corresponding to the current position feedback signal is greater than or equal to the target value of the position-sensitive detector. If the amplitude of the current resonant scanning mirror is greater than the preset lower limit, the amplitude of the current resonant scanning mirror is reduced by one amplitude step, and the frequency modulation module enable flag is set.

[0012] If the amplitude of the resonant scanning mirror is at a preset lower limit, then the frequency modulation module enable flag is set. Step S4.4: If the amplitude of the current resonant scanning mirror is equal to the preset upper limit or the preset lower limit, then set the adaptive frequency modulation enable flag and save the position value and amplitude value of the resonant scanning mirror corresponding to the current position feedback signal.

[0013] Preferably, in step S5, based on the resonant frequency point, the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module, which specifically includes: Step S5.1: The frequency modulation module performs a second time count. If the second time count is less than the frequency period, the value of the second time count is incremented by one. If the second time count is not less than the frequency period, proceed to step S5.2. Step S5.2: When the value of the second time counter reaches a preset threshold, the value of the second time counter is reset to zero. If the amplitude value of the current resonant scanning mirror is less than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror remains unchanged. If the amplitude value of the current resonant scanning mirror is greater than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror is changed. Step S5.3: If the amplitude value of the current resonant scanning mirror is equal to the amplitude value of the resonant scanning mirror in the previous cycle, then it is determined that the amplitude value of the current resonant scanning mirror is at the preset lower limit or at the preset upper limit.

[0014] Preferably, step S5 further includes: Step S5.4: If the amplitude value of the resonant scanning mirror is at the preset lower limit, then stop the operation of the amplitude modulation module and maintain the stability of the target value of the position sensitive detector through the frequency modulation module; Step S5.5: If the amplitude value of the resonant scanning mirror is at the preset upper limit, then stop the operation of the amplitude modulation module, and use the frequency modulation module to make the position value of the resonant scanning mirror corresponding to the position feedback signal reach the target value.

[0015] Preferred options also include: Step S6: Based on the filtered position feedback signal, calculate the frequency and amplitude of the resonant scanning mirror in the next cycle; Step S7: Determine whether the resonant scanning mirror has reached the desired position. If it has reached the desired position, end the control. If it has not reached the desired position, return to step S2.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention proposes a frequency-temperature adaptive control system and method for a resonant scanning mirror. This system can stabilize the scanning angle of the resonant mirror at a certain angle, and through adaptive adjustment of frequency and amplitude, enable the resonant scanning mirror to resist the effects of temperature changes. Ultimately, this ensures that the lidar scanning mirror can adapt to different temperature conditions and achieve stable driving. Attached Figure Description

[0017] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the drawings described below are one embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort: Figure 1 A flowchart of the frequency-temperature adaptive control system for a resonant scanning mirror provided in an embodiment of the present invention; Figure 2 This is a flowchart of frequency point initialization search provided in an embodiment of the present invention. Detailed Implementation

[0018] The following is in conjunction with the appendix Figure 1 and Figure 2 The following detailed description further illustrates the frequency-temperature adaptive control system and method for the resonant scanning mirror proposed in this invention. The advantages and features of this invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, used only to facilitate and clearly illustrate the embodiments of this invention. Please refer to the accompanying drawings to make the objectives, features, and advantages of this invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0019] The lack of a technical solution for controlling the frequency of resonant scanning mirrors based on temperature changes in existing technologies has led to the problem of resonant scanning mirrors malfunctioning.

[0020] On one hand, this embodiment provides a frequency-temperature adaptive control system for a resonant scanning mirror, comprising: a resonant scanning mirror driving module connected to the resonant scanning mirror for driving the resonant scanning mirror; a position-sensitive detector disposed on one side of the resonant scanning mirror to obtain the angle of the resonant scanning mirror; an initialization search module connected to both the position-sensitive detector and the resonant scanning mirror to search for the resonant frequency point of the resonant scanning mirror using a fixed frequency step size; an amplitude modulation module connected to the initialization search module for adjusting the amplitude of the resonant scanning mirror to a target value; and a frequency modulation module connected to the amplitude modulation module for adaptively adjusting the frequency of the resonant scanning mirror.

[0021] The position-sensitive detector acquires the angle of the resonant scanning mirror and converts it into a position feedback signal.

[0022] After completing the search for the resonant frequency point, the initialization search module sets the search flag and the adaptive amplitude modulation enable flag.

[0023] The adjustment of the amplitude of the resonant scanning mirror to the target value specifically involves: adjusting the amplitude of the resonant scanning mirror to the target value of the position-sensitive detector based on the difference between the current position feedback signal of the position-sensitive detector and the target value of the position-sensitive detector.

[0024] On the other hand, this embodiment also provides a frequency-temperature adaptive control method for a resonant scanning mirror. Using the aforementioned frequency-temperature adaptive control system for a resonant scanning mirror, the method includes: Step S1: After the system is powered on, power on the resonant scanning mirror drive module, and set the initial frequency and initial amplitude of the resonant scanning mirror through the resonant scanning mirror drive module.

[0025] Step S2: Use a position-sensitive detector to acquire a position feedback signal about the angle of the resonant scanning mirror, and filter the position feedback signal to obtain a filtered position feedback signal.

[0026] Step S3: Obtain the resonant frequency point through the initialization search module, which specifically includes: Step S3.1: Set the target value, amplitude step size, and frequency step size of the position sensitive detector. Specifically, set the PSD target value T_target, amplitude step size step_a, and frequency step size step_f.

[0027] Step S3.2: Set the initial frequency value init_f and the initial amplitude value init_a of the resonant scanning mirror.

[0028] Step S3.3: Sample the current position feedback signal T_cur of the position sensitive detector.

[0029] Step S3.4: At every frequency step_f, sample the current corresponding position feedback signal T_cur, repeat the above sampling several times, determine the maximum value among all the position feedback signals, and determine the frequency of the resonant scanning mirror corresponding to the maximum value among all the position feedback signals.

[0030] Step S3.5: The search ends. Set the search flag search_flag=True and the adaptive amplitude modulation enable flag amp_flag=True.

[0031] Step S4: Based on the resonant frequency point, the amplitude modulation module adjusts the amplitude of the resonant scanning mirror to the target value, specifically including: Step S4.1: The amplitude modulation module performs a first time count. If the first time count is less than the amplitude period, the first time count is incremented by one. If the first time count is not less than the amplitude period, then proceed to step S4.2.

[0032] In this embodiment, the specific steps are as follows: when the first time count amp_cnt is less than the amplitude period A_period, the count is incremented by 1; otherwise, proceed to step S4.2 below.

[0033] Step S4.2: When the first time count reaches the preset threshold, the count is reset, that is, the count is cleared to zero.

[0034] When the position value T of the resonant scanning mirror corresponding to the current position feedback signal is less than the target value T_target of the position sensitive detector.

[0035] If the amplitude of the current resonant scanning mirror is less than the preset upper limit value V_max, then the amplitude of the current resonant scanning mirror is increased by one amplitude step, i.e., amp = amp + step_a, and the frequency modulation module enable flag freq_flag is set to False.

[0036] If the amplitude of the resonant scanning mirror is at the preset upper limit, then set the frequency modulation module start flag freq_flag=True.

[0037] The preset upper and lower limits represent the upper and lower boundary values ​​of the resonant scanning mirror at different stable angles, and are preset values ​​for the system.

[0038] In this embodiment, specifically: when the time count reaches a critical value, the count is reset to 0. If the current PSD position T is less than the PSD target value T_target, and if the current amplitude is less than the upper limit value V_max, the amplitude is increased by one step amp = amp + step_a, and the frequency modulation module start flag freq_flag is set to False. If the current amplitude is at the upper limit value, the frequency modulation module start flag freq_flag is set to True.

[0039] Step S4.3: The position value T of the resonant scanning mirror corresponding to the current position feedback signal is greater than or equal to the target value T_target of the position sensitive detector.

[0040] If the amplitude of the current resonant scanning mirror is greater than the preset lower limit value V_min, then the amplitude of the current resonant scanning mirror is reduced by one amplitude step, i.e., amp = amp - step_a, and the frequency modulation module enable flag freq_flag is set to True.

[0041] If the amplitude of the resonant scanning mirror is at the preset lower limit, then set the frequency modulation module enable flag freq_flag=True.

[0042] Step S4.4: If the amplitude of the current resonant scanning mirror is equal to the preset upper limit or the preset lower limit, then set the adaptive amplitude modulation enable flag amp_flag=False and the adaptive frequency modulation enable flag freq_flag=True, and save the position value T_pre=T and amplitude value amp_pre=amp of the resonant scanning mirror corresponding to the current position feedback signal.

[0043] Step S5: Based on the resonant frequency, the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module to achieve adaptive frequency-temperature control of the resonant scanning mirror, specifically including: Step S5.1: The frequency modulation module performs a second time count freq_cnt. If the second time count freq_cnt is less than the frequency period F_period, the value of the second time count is incremented by one. If the value of the second time count is not less than the frequency period, proceed to step S5.2. In this embodiment, the specific steps are as follows: when the second time count freq_cnt is less than the frequency period F_period, the count is incremented by 1; otherwise, proceed to step S5.2.

[0044] Step S5.2: When the value of the second time count reaches a preset threshold, the value of the second time count is cleared to zero.

[0045] If the amplitude value of the current resonant scanning mirror is less than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror remains unchanged. If the amplitude value of the current resonant scanning mirror is greater than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror is changed.

[0046] That is, when the second time count reaches the critical value, the count is cleared to 0. If the current amplitude value amp is less than the previous amplitude value amp_pre, the frequency direction remains unchanged orient=orient. If the current amplitude is greater than the amplitude amp_pre of the previous cycle, the frequency direction is reversed orient=-1*orient. Finally, the frequency freq=freq+orient*step_f is set.

[0047] Step S5.3: If the amplitude value of the current resonant scanning mirror is equal to the amplitude value of the resonant scanning mirror in the previous cycle, then it is determined that the amplitude value of the current resonant scanning mirror is at the preset lower limit or at the preset upper limit.

[0048] Step S5.4: If the current amplitude value of the resonant scanning mirror is at the preset lower limit value, stop the operation of the amplitude modulation module, and maintain the stability of the target value of the position sensitive detector through the frequency modulation module.

[0049] When the amplitude remains constant and is at the lower limit value V_min, the operation of the amplitude modulation module is stopped. The preset lower limit value is determined according to the boundary value of the dynamic range of the amplitude. At this time, the frequency modulation module continues to operate, and the target of frequency modulation changes to maintaining the stability of the PSD target value, rather than the change of the front and rear amplitudes. If the current PSD value is greater than the PSD target value, compare the current PSD value T with the PSD value T_pre before frequency modulation. If T<T_pre, it is determined that the frequency modulation direction is correct, and the direction is maintained as orient=orient. If T>T_pre, it is determined that the frequency modulation direction is wrong, and the frequency modulation direction is changed to orient=-1*orient. If the current PSD value is less than the PSD target value, start amplitude modulation, set the enable flag of the amplitude modulation module as amp_flag=True, and set the enable flag of the frequency modulation module as freq_flag=False.

[0050] Step S5.5: If the current amplitude value of the resonant scanning mirror is at the preset upper limit value, stop the operation of the amplitude modulation module, and make the position value of the resonant scanning mirror corresponding to the position feedback signal reach the target value through the frequency modulation module.

[0051] When the amplitude remains constant and is at the preset upper limit value V_max, amplitude modulation is stopped. The preset upper limit value is determined according to the boundary value of the dynamic range of the amplitude. At this time, frequency modulation continues, that is, the operation of the amplitude modulation module is stopped, and the frequency modulation module continues to operate. At this time, the target of frequency modulation changes to making the PSD reach the target value. If the current PSD value is greater than the PSD target value, compare the current PSD value with the PSD value before frequency modulation. If T>T_pre, it is determined that the frequency modulation direction is correct, and the direction is maintained as orient=orient. If T<T_pre, it is determined that the frequency modulation direction is wrong, and the frequency modulation direction is changed to orient=-1*orient. If the current PSD value is greater than the PSD target value, start amplitude modulation, set the enable flag of the amplitude modulation module as amp_flag=True, and set the enable flag of the frequency modulation module as freq_flag=False.

[0052] Step S6: Calculate the frequency and amplitude of the resonant scanning mirror in the next cycle according to the filtered position feedback signal.

[0053] Step S7: Determine whether the resonant scanning mirror reaches the expected position. If the expected position is reached, the control is ended; if the expected position is not reached, the process returns to step S2.

[0054] In summary, this embodiment proposes a frequency-temperature adaptive control method for a resonant scanning mirror. This method can stabilize the scanning angle of the resonant mirror at a certain angle, and through adaptive adjustment of frequency and amplitude, enable the resonant scanning mirror to resist the effects of temperature changes. Ultimately, this ensures that the lidar scanning mirror can adapt to different temperature conditions and achieve stable driving.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0056] It should be noted that the apparatus and methods disclosed in the embodiments herein can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments herein. In this regard, each block in a flowchart or block diagram may represent a module, program, or part of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system to perform the specified function or action, or can be implemented using a combination of dedicated hardware and computer instructions.

[0057] In addition, the functional modules in the various embodiments of this article can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0058] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A frequency-temperature adaptive control method for a resonant scanning mirror, comprising a frequency-temperature adaptive control system for the resonant scanning mirror, characterized in that, The system includes: A resonant scanning mirror drive module, which is connected to the resonant scanning mirror and is used to drive the resonant scanning mirror; A position-sensitive detector is disposed on one side of the resonant scanning mirror to obtain the angle of the resonant scanning mirror; An initialization search module is established, which is connected to the position-sensitive detector and the resonant scanning mirror respectively, to search for the resonant frequency point of the resonant scanning mirror by means of a fixed frequency step size; An amplitude modulation module, connected to the initialization search module, is used to adjust the amplitude of the resonant scanning mirror to the target value; A frequency modulation module, which is connected to the amplitude modulation module, is used to adaptively adjust the frequency of the resonant scanning mirror; The method includes: Step S1: Set the initial frequency and initial amplitude of the resonant scanning mirror using the resonant scanning mirror driving module; Step S2: Use a position-sensitive detector to acquire a position feedback signal about the angle of the resonant scanning mirror, and filter the position feedback signal to obtain a filtered position feedback signal; Step S3: Obtain the resonant frequency point through the initialization search module; Step S4: Based on the resonant frequency point, the amplitude modulation module adjusts the amplitude of the resonant scanning mirror to the target value; Step S5: Based on the resonant frequency point, the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module to achieve adaptive frequency-temperature control of the resonant scanning mirror. In step S3, the resonant frequency point is obtained through the initialization search module, which specifically includes: Step S3.1: Set the target value, amplitude step size, and frequency step size of the position-sensitive detector; Step S3.2: Set the initial values ​​of the frequency and amplitude of the resonant scanning mirror; Step S3.3: Sample the current position feedback signal of the position-sensitive detector; Step S3.4: At each frequency step, sample the current corresponding position feedback signal, repeat the above sampling several times, determine the maximum value among all the position feedback signals, and determine the frequency of the resonant scanning mirror corresponding to the maximum value among all the position feedback signals. In step S4, the amplitude modulation module adjusts the amplitude of the resonant scanning mirror to the target value, specifically including: Step S4.1: The amplitude modulation module performs a first time count. If the first time count is less than the amplitude period, the first time count is incremented by one. If the first time count is not less than the amplitude period, then proceed to step S4.

2. The amplitude period is the amplitude change control period of the resonant scanning mirror. The specific setting value is determined based on different systems. Step S4.2: When the first time count reaches a preset threshold, the count is reset. When the position value of the resonant scanning mirror corresponding to the current position feedback signal is less than the target value of the position-sensitive detector, If the amplitude of the current resonant scanning mirror is less than the preset upper limit, then the amplitude of the current resonant scanning mirror is increased by one amplitude step, and the frequency modulation module enable flag is set. If the amplitude of the resonant scanning mirror is at the preset upper limit, then the frequency modulation module start flag is set. Step S4.3: The position value of the resonant scanning mirror corresponding to the current position feedback signal is greater than or equal to the target value of the position-sensitive detector. If the amplitude of the current resonant scanning mirror is greater than the preset lower limit, then the amplitude of the current resonant scanning mirror is reduced by one amplitude step, and the frequency modulation module enable flag is set. If the amplitude of the resonant scanning mirror is at a preset lower limit, then the frequency modulation module enable flag is set. Step S4.4: If the amplitude of the current resonant scanning mirror is equal to the preset upper limit or the preset lower limit, then set the adaptive frequency modulation enable flag and save the position value and amplitude value of the resonant scanning mirror corresponding to the current position feedback signal. In step S5, based on the resonant frequency point, the frequency of the resonant scanning mirror is adaptively adjusted by the frequency modulation module, which specifically includes: Step S5.1: The frequency modulation module performs a second time count. If the second time count is less than the frequency period, the value of the second time count is incremented by one. If the second time count is not less than the frequency period, proceed to step S5.

2. Step S5.2: When the value of the second time counter reaches a preset threshold, the value of the second time counter is reset to zero. If the amplitude value of the current resonant scanning mirror is less than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror remains unchanged. If the amplitude value of the current resonant scanning mirror is greater than the amplitude value of the resonant scanning mirror in the previous cycle, then the frequency direction of the resonant scanning mirror is changed. Step S5.3: If the amplitude value of the current resonant scanning mirror is equal to the amplitude value of the resonant scanning mirror in the previous cycle, then it is determined that the amplitude value of the current resonant scanning mirror is at the preset lower limit or at the preset upper limit. Step S5 further includes: Step S5.4: If the amplitude value of the resonant scanning mirror is at the preset lower limit, then stop the operation of the amplitude modulation module and maintain the stability of the target value of the position sensitive detector through the frequency modulation module; Step S5.5: If the amplitude value of the resonant scanning mirror is at the preset upper limit, then stop the operation of the amplitude modulation module, and use the frequency modulation module to make the position value of the resonant scanning mirror corresponding to the position feedback signal reach the target value.

2. The frequency-temperature adaptive control method for the resonant scanning mirror as described in claim 1, characterized in that, The position-sensitive detector acquires the angle of the resonant scanning mirror and converts it into a position feedback signal.

3. The frequency-temperature adaptive control method for the resonant scanning mirror as described in claim 2, characterized in that, After completing the search for the resonant frequency point, the initialization search module sets the search flag and the adaptive amplitude modulation enable flag.

4. The frequency-temperature adaptive control method for the resonant scanning mirror as described in claim 3, characterized in that, The adjustment of the amplitude of the resonant scanning mirror to the target value specifically involves: adjusting the amplitude of the resonant scanning mirror to the target value of the position-sensitive detector based on the difference between the current position feedback signal of the position-sensitive detector and the target value of the position-sensitive detector.

5. The frequency-temperature adaptive control method for the resonant scanning mirror as described in claim 1, characterized in that, Also includes: Step S6: Based on the filtered position feedback signal, calculate the frequency and amplitude of the resonant scanning mirror in the next cycle; Step S7: Determine whether the resonant scanning mirror has reached the desired position. If it has reached the desired position, end the control. If it has not reached the desired position, return to step S2.

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