A resonant MEMS scanning mirror closed-loop control system and method

Abstract

The application discloses a resonant MEMS scanning mirror closed-loop control system and method, and the control system comprises a driving module, a collecting module and a driving module. The driving module is used for generating an original driving signal and driving a MEMS scanning mirror to receive and reflect laser emitted by a laser light source according to the original driving signal. The collecting module is used for receiving the light signal reflected by the MEMS scanning mirror and obtaining light path information. The driving module is further used for calculating an actual maximum deflection angle of the MEMS scanning mirror according to the light path information, updating the original driving signal according to an error value of the actual maximum deflection angle and a target maximum control deflection angle. The application is helpful to improve the stability of the MEMS scanning mirror and solve the problem that the scanning angle is greatly reduced due to the change of the resonant frequency caused by factors such as material aging and temperature drift of the resonant MEMS scanning mirror.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of resonant MEMS scanning mirrors, and particularly relates to a resonant MEMS scanning mirror closed-loop control system and method. BACKGROUND

[0002] A MEMS scanning mirror refers to a driveable mirror that is manufactured on a semiconductor silicon with a size of micro-nanometer by using a MEMS technology, and is usually composed of four parts, i.e., a micro-mirror surface, a micro-driver, an elastic structure and a support structure. The working principle is to drive the rotation of the micro-mirror surface by using the micro-driver, so as to control the direction of the reflected light. The MEMS scanning mirror has the advantages of small size, light weight, low power consumption, fast response speed, high scanning frequency and the like. The resonant MEMS scanning mirror is a key device of a laser radar, and is mainly used as a scanner in a MEMS laser radar to meet the working requirements of small size, low power consumption and high resolution of the laser radar.

[0003] In order to realize the low-power-consumption and large-angle working of the scanning mirror, the resonant MEMS scanning mirror must adopt a closed-loop driving mode. In order to improve the dynamic performance of the closed-loop control, the closed-loop circuit must adopt a digital driving scheme. The MEMS scanning mirror is affected by the ambient temperature, and the change of the ambient temperature will change the frequency characteristics, thereby causing the scanning angle to be small. The existing open-loop control has poor transient performance, long regulation time and poor anti-interference ability, and is not suitable for application occasions where the external temperature changes significantly.

[0004] There is also a closed-loop driving circuit based on a phase-locked loop for driving a resonant mode horizontal scanning mirror. The circuit can make the MEMS oscillate at its resonant frequency accurately, and maximize the scanning angle of the micro-mirror. However, in order to maximize the scanning angle of the micro-mirror, the driving voltage of the driving circuit is too large, and at least 60V is required. In 2015, Peng Zuo et al. used a PID algorithm to control the electromagnetic MEMS torsional micro-mirror, realized an angle tracking of 0.3 degrees at a minimum, and the regulation time of the system was only 15ms. However, the control scheme is mainly for the scanning mirror working in the quasi-static mode, and does not study the case that the micro-mirror produces resonance under the excitation of a sinusoidal signal. SUMMARY

[0005] The present application aims to at least solve one of the technical problems in the related art to some extent.

[0006] To this end, the present application aims at a closed-loop control system of a resonant MEMS scanning mirror, and a hardware implementation solves the problems of poor temperature adaptability and insufficient stability in the existing MEMS scanning mirror technology. Through closed-loop control, the frequency of the scanning mirror is automatically compensated during the change of the ambient temperature, the driving frequency is stabilized at the resonant frequency of the scanning mirror, so as to improve the stability of the scanning angle of the MEMS scanning mirror in the running state.

[0007] To achieve the above-mentioned purpose, the present application proposes a closed-loop control system of a resonant MEMS scanning mirror, comprising:

[0008] a driving module for generating an original driving signal and driving the MEMS scanning mirror to receive and reflect the laser emitted by the laser light source according to the original driving signal;

[0009] a collection module for receiving the light signal reflected by the MEMS scanning mirror and obtaining the optical path information;

[0010] The driving module is further configured to calculate the actual maximum deflection angle of the MEMS scanning mirror according to the optical path information, and update the original driving signal according to the error value of the actual maximum deflection angle and the target maximum control deflection angle.

[0011] The closed-loop control system of the resonant MEMS scanning mirror of the embodiment of the present application can further have the following additional technical features:

[0012] Further, the collection module comprises a PSD sensor and an AD conversion chip, wherein the PSD sensor is configured to receive the reflected laser of the MEMS scanning mirror and convert the displacement amount of the reflected laser on the PSD sensor into a voltage signal of the PSD sensor; and the AD conversion chip is configured to receive and convert the voltage signal of the PSD sensor to obtain a displacement signal and transmit the displacement signal to the master control chip.

[0013] Further, the driving module comprises a signal generation unit, a power amplifier unit and a master control chip, wherein the signal generation unit is configured to generate the original driving signal of the MEMS scanning mirror; the power amplifier unit is configured to amplify the original driving signal to the voltage required by the MEMS scanning mirror; and the master control chip is configured to calculate the actual maximum deflection angle of the MEMS scanning mirror within a preset time according to an optical path conversion formula.

[0014] Further, the master control chip is further configured to calculate the error value of the actual maximum deflection angle and the target maximum deflection angle by using a PI algorithm to obtain a frequency control word, and feed back the frequency control word to the signal generation module; and the signal generation module is further configured to update the original driving signal according to the frequency control word.

[0015] Further, the system further comprises a power module, configured to provide power for the MEMS scanning mirror, the acquisition module and the driving module.

[0016] To achieve the above object, another aspect of the present application provides a resonant MEMS scanning mirror closed-loop control method, comprising:

[0017] An original driving signal is acquired, and the MEMS scanning mirror is driven according to the original driving signal to receive and reflect laser emitted by a laser light source;

[0018] The light path information of the light signal reflected by the MEMS scanning mirror is acquired;

[0019] The actual maximum deflection angle of the MEMS scanning mirror is calculated according to the light path information, and the original driving signal is updated according to the error value of the actual maximum deflection angle and a target maximum control deflection angle.

[0020] The resonant MEMS scanning mirror closed-loop control system and method of the embodiment of the present application solve the problems of poor temperature adaptability and insufficient stability in the existing MEMS scanning mirror technology. Through closed-loop control, the scanning mirror frequency is automatically compensated during the change of the environmental temperature, the driving frequency is stabilized at the resonant frequency of the scanning mirror, so as to improve the stability of the scanning angle of the MEMS scanning mirror in the running state.

[0021] The present application also provides a computer device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the resonant MEMS scanning mirror closed-loop control method according to any one of the above embodiments when executing the program.

[0022] Additional aspects and advantages of the present application will be given in part in the following description, will become apparent from the following description, or will be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0024] Figure 1 is a structural schematic diagram of the resonant MEMS scanning mirror closed-loop control system according to the embodiment of the present application;

[0025] Figure 2 is a closed-loop control schematic diagram according to the embodiment of the present application;

[0026] Figure 3 is a whole schematic diagram of the driving circuit according to the embodiment of the present application;

[0027] Figure 4 is a drive circuit diagram according to an embodiment of the present application;

[0028] Figure 5 is a flow chart of a closed-loop control method of a resonant MEMS scanning mirror according to an embodiment of the present application;

[0029] Figure 6 is a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should belong to the protection scope of the present application.

[0032] The closed-loop control system, method and device of a resonant MEMS scanning mirror according to an embodiment of the present application will be described below with reference to the accompanying drawings.

[0033] Figure 1 is a structural schematic diagram of a closed-loop control system of a resonant MEMS scanning mirror according to an embodiment of the present application.

[0034] As shown in Figure 1 , the system comprises:

[0035] a driving module 100, configured to generate an original driving signal and drive the MEMS scanning mirror to receive and reflect the laser emitted by a laser light source according to the original driving signal;

[0036] a collecting module 200, configured to receive the light signal reflected by the MEMS scanning mirror and obtain light path information;

[0037] The driving module 100 is further configured to calculate an actual maximum deflection angle of the MEMS scanning mirror according to the light path information, and update the original driving signal according to an error value between the actual maximum deflection angle and a target maximum control deflection angle.

[0038] Further, the collecting module 200 comprises a PSD sensor and an AD conversion chip, wherein,

[0039] a PSD sensor configured to receive the reflected laser light from the MEMS scanning mirror and convert a displacement of the reflected laser light on the PSD sensor into a voltage signal of the PSD sensor;

[0040] an AD conversion chip configured to receive and convert the voltage signal of the PSD sensor into a displacement signal and transmit the displacement signal to the control chip.

[0041] Specifically, the two-dimensional PSD sensor, the AD conversion chip, and the laser source of the acquisition module 200 are configured to emit laser light to the MEMS scanning mirror, reflect the laser light, receive the reflected laser light, convert a displacement of the reflected laser light on the PSD sensor into a voltage signal, collect the voltage signal from the PSD sensor, save and transmit the voltage signal to the control chip, and calculate an actual maximum deflection angle of the MEMS scanning mirror within a predetermined time according to an optical path conversion formula.

[0042] Further, the driving module 100 includes a signal generation unit, a power amplifier unit, and a control chip, wherein,

[0043] The signal generation unit is configured to generate an original driving signal of the MEMS scanning mirror.

[0044] The power amplifier unit is configured to amplify the original driving signal to a voltage required by the MEMS scanning mirror; and

[0045] The control chip is configured to calculate an actual maximum deflection angle of the MEMS scanning mirror within a predetermined time according to an optical path conversion formula.

[0046] Specifically, the signal generation unit generates an original signal, the original signal includes two sinusoidal signals for representing torsional and bending motions of the MEMS scanning mirror in a resonant state, the power amplifier unit is configured to amplify the signal to a voltage required by the MEMS scanning mirror for operation, and improve an output power of the signal, and the control chip is configured to implement closed-loop control of the MEMS scanning mirror, and the MEMS scanning mirror receives the driving signal from the signal generation module to perform resonant motion.

[0047] Further, the control chip receives the displacement signal from the AD conversion chip, converts the displacement signal into an actual deflection angle and calculates an actual maximum deflection angle according to the optical path conversion formula, calculates an error value between the target maximum deflection angle and the actual maximum deflection angle, and adjusts a frequency of the driving signal through a PI algorithm according to the error value.

[0048] It can be understood that the error value is obtained by comparing with the target resonant maximum deflection angle, the compensation frequency is obtained through PI (proportional-integral) control of the error value, the compensation frequency is fed back to the driving signal of the MEMS scanning mirror to make the MEMS scanning mirror work in a resonant state, and closed-loop control of the MEMS scanning mirror is achieved.

[0049] Further, the power module is further included to generate positive and negative voltages required by the power amplifier unit and provide required low ripple voltages for each module to ensure normal and stable operation of the control circuit.

[0050] The resonant MEMS scanning mirror closed-loop control system according to the embodiment of the application will be described in detail below with reference to the accompanying drawings.

[0051] As an example, the resonant MEMS scanning mirror closed-loop control system according to the embodiment of the application is shown in the architecture diagram as shown in Figure 1 .

[0052] The laser, the power module, the MEMS scanning mirror, the PSD sensor, the AD conversion chip, the main control chip, the signal generation module and the power amplifier module are included.

[0053] The natural frequencies of the MEMS scanning mirror y-axis torsion shaft and the x-axis bending shaft according to the embodiment are 798.5 Hz and 1102.6 Hz, the main control chip is a floating-point processor TMS320F28335 with a high-speed processing capacity of 150 MHz and a 32-bit floating-point processing unit, the signal generation module is a DDS chip with a signal frequency accuracy of 0.004 Hz, which contains 10-bit DA conversion, the power amplifier module amplifies the driving signal by 10 times and provides DC bias for the signal, the PSD sensor has a maximum receivable area of 4.5 cm x 4.5 cm, an output range of ±10 V and a proportional coefficient of distance and voltage of 400 mV / mm, the AD conversion chip is 12-bit with a sampling frequency of 1 MHz and an input range of ±10 V, and the power module generates ±15 V, 5 V and 3.3 V low ripple voltages.

[0054] In the embodiment of the application, the maximum deflection angle of the MEMS scanning mirror under resonance is:

[0055]

[0056]

[0057]

[0058]

[0059] wherein θ y-max is the maximum deflection angle of the torsion shaft under resonance, θ x，max is the maximum deflection angle of the bending shaft under resonance, z1 and z2 are excitation amplitudes corresponding to two resonance frequencies, l x is the length of the torsion beam, and l ywhere y is the distance from the center of the lens to the y-axis, ζ1, ζ2 are damping ratios, m is the mass of the lens, K1 is the elastic coefficient of the torsional beam structure, K2 is the elastic coefficient of the cantilever beam structure. C1 is the damping coefficient of the torsional beam structure, C2 is the damping coefficient of the cantilever beam structure, and ω1 and ω2 represent the natural circular frequencies of the torsional motion of the lens around the y-axis and the bending motion of the lens around the x-axis.

[0060] Based on the above characteristics of the MEMS scanning mirror in the application, in one specific embodiment of the application, an angle signal is obtained based on detection of reflected laser by a PSD sensor, PI operation is directly performed on the maximum deflection angle of the scanning mirror to obtain a frequency control word, and stable operation of the scanning mirror is realized by modifying the frequency of the driving signal in the signal generation module.

[0061] Further, the closed-loop control combines Figure 2 and Figure 3 , and specifically includes the following steps:

[0062] 1-1) The driving circuit generates a driving signal

[0063] 1-2) The scanning mirror receives the driving signal from the driving circuit to generate vibration in the torsional and bending axis directions;

[0064] 1-3) The PSD sensor converts the amplitude signal of the scanning mirror into a voltage signal u o (t), and reads out the voltage signal through AD sampling;

[0065] 1-4) The master control chip performs digital filtering on the voltage signal u o (t) representing the amplitude, and specifically uses an FIR digital filter, and the filtering mode is:

[0066]

[0067] where h(k) represents the impulse response of the filter, and the order of the filter is N-1;

[0068] 1-5) The deflection angle of the scanning mirror is calculated according to the PSD calibration value and the related optical path calculation method based on the filtered voltage signal y(t);

[0069] 1-6) The maximum deflection angle is subjected to proportional integral (PI) operation to obtain a compensation angular frequency w 1i , w 2i , and output to the signal generation module, so that the scanning mirror operates at the resonant frequency and ensures the stability of the scanning angle.

[0070] The closed-loop control system of the resonant MEMS scanning mirror designed based on the application, in one specific implementation of the application, builds a closed-loop control system for the temperature drift characteristics of the MEMS scanning mirror to test and compensate the scanning mirror for temperature, so that the scanning mirror can still maintain the stability of the scanning angle during the temperature change. Figure 4 The driving circuit of the embodiment of the application is shown in the figure.

[0071] Further, the temperature compensation method comprises the following steps:

[0072] 2-1) First, place the MEMS scanning mirror system in a temperature chamber, and prepare for power supply and signal transmission;

[0073] 2-2) Change the temperature of the temperature chamber from 40 to 60 degrees Celsius in steps of 5 degrees Celsius, and maintain each temperature test point for more than 20 minutes;

[0074] 2-3) According to the aforementioned steps 1-1) to 1-6), establish an angle detection and closed-loop control loop, and record the scanning angle change and closed-loop output data at each temperature test point;

[0075] 2-4) According to the above data, establish a relationship between the driving signal and the closed-loop output feedback control frequency, and obtain the temperature-compensated closed-loop output The scanning mirror after frequency compensation maintains resonant motion.

[0076] In summary, the application generates a driving signal with an initial frequency from the driving module to make the MEMS scanning mirror vibrate, and the laser emission is on the MEMS scanning mirror. The angle information about the MEMS scanning mirror is obtained through the PSD (position sensor) on the acquisition module, and the information is collected and converted to obtain the actual maximum deflection angle. Then, by comparing with the target resonant maximum deflection angle, the error value is obtained, and the error value is obtained through PI (proportional-integral) control to obtain the compensation frequency. The compensation frequency is fed back to the driving signal of the MEMS scanning mirror to make the MEMS scanning mirror work in the resonant state, and the closed-loop control of the MEMS scanning mirror is realized. The system helps to improve the stability of the MEMS scanning mirror, and solves the problem of large reduction of the scanning angle caused by the change of the resonant frequency of the resonant MEMS scanning mirror due to factors such as material aging and temperature drift.

[0077] In order to realize the above-mentioned embodiment, as Figure 5 shown, the embodiment further provides a resonant MEMS scanning mirror closed-loop control method, which comprises:

[0078] S1, obtaining an original driving signal, and driving the MEMS scanning mirror to receive and reflect the laser emitted by a laser light source according to the original driving signal;

[0079] S2, acquiring optical path information of the light signal reflected by the MEMS scanning mirror;

[0080] S3, calculating the actual maximum deflection angle of the MEMS scanning mirror according to the optical path information, and updating the original driving signal according to an error value between the actual maximum deflection angle and a target maximum control deflection angle.

[0081] Further, in the step S2, the MEMS scanning mirror is reflected by laser, and the displacement of the reflected laser is converted into a voltage signal; and the voltage signal is converted into a displacement signal.

[0082] Further, in the step S3, the original driving signal of the MEMS scanning mirror is acquired; the original driving signal is amplified to a voltage required by the MEMS scanning mirror; and the actual maximum deflection angle of the MEMS scanning mirror within a preset time is calculated according to an optical path conversion formula.

[0083] Further, in the step S3, the error value between the actual maximum deflection angle and a target maximum deflection angle is calculated by using a PI algorithm to obtain a frequency control word, and the original driving signal is updated according to the frequency control word.

[0084] Specifically, the present application provides a resonant MEMS scanning mirror closed-loop control method, which is realized by the following algorithm and includes the following steps:

[0085] The signal generation unit generates an initial driving signal

[0086] The driving signal is outputted by the power unit i (t);

[0087] The PSD receives the reflected laser light and outputs a displacement signal u o (t);

[0088] The PSD is calibrated, and the fixed laser light at different displacements is recorded on the PSD to obtain a corresponding relationship between the displacement and the output voltage of the PSD;

[0089] The AD conversion chip collects the displacement signal, and the master control chip calculates the actual deflection angle according to an optical path conversion formula, and the calculation method of the optical path conversion formula is as follows:

[0090]

[0091] Wherein a is the vertical distance between the mirror surface of the scanning mirror and the PSD sensor, and l is the moving distance of the light spot on the PSD sensor;

[0092] The master control chip calculates the error values θ1 and θ2 of the actual maximum deflection angles of the two axes and the target maximum deflection angles, and calculates the compensation angular frequency w by using a PI control algorithm 1i, w 2i ;

[0093] The PI control algorithm is:

[0094]

[0095] Wherein u(t) is the control signal of the PI controller output, e(t) is the angle error value, K P is the proportional coefficient, T I is the integral time constant.

[0096] The signal generation unit receives the frequency control word from the main control chip, generates the driving signal To drive the scanning mirror to work in the resonant state.

[0097] The present application has the functions of driving signal modulation, angle detection and temperature drift compensation. The present application creatively represents the amplitude change caused by the resonant frequency change as the maximum deflection angle change in the scanning mirror amplitude detection, which can directly obtain the working condition of the scanning mirror without calculating the resonant frequency change of the scanning mirror, avoids the defect that the frequency characteristics of the MEMS scanning mirror are easily affected by temperature, and can realize more accurate control. In addition, the present application directly obtains the feedback control frequency through PI operation of the deflection angle, establishes a closed loop control loop, and provides a more simple method.

[0098] In order to realize the method of the above-mentioned embodiments, the present application further provides a computer device, as shown in Figure 6 The computer device 600 comprises a memory 601 and a processor 602; wherein the processor 602 runs the program corresponding to the executable program code stored in the memory 601 by reading the executable program code, so as to realize each step of the resonant MEMS scanning mirror closed loop control method described above.

[0099] In addition, the terms "first", "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0100] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0101] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and the person skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A resonant MEMS scanning mirror closed-loop control system, characterized in that, The control system includes: The driving module is used to generate a raw driving signal and drive the MEMS scanning mirror to receive and reflect the laser emitted by the laser source according to the raw driving signal; The acquisition module is used to receive the optical signal reflected by the MEMS scanning mirror and obtain optical path information; The driving module is also used to calculate the actual maximum deflection angle of the MEMS scanning mirror based on the optical path information, and update the original driving signal based on the error value between the actual maximum deflection angle and the target maximum control deflection angle. Also includes: With a constant driving voltage, the maximum deflection angle of the MEMS scanning mirror in the resonant state is: in This represents the maximum deflection angle of the torsional shaft under resonance. The maximum deflection angle of the bending axis under resonance. and These are the excitation amplitudes corresponding to the two resonant frequencies. For the length of the torsion beam, This refers to the distance from the center of mass of the lens to the y-axis. Where m is the damping ratio and m is the lens mass. The elastic modulus of the torsion beam structure, The elastic modulus of the cantilever beam structure; The damping coefficient of the torsion beam structure is... The damping coefficient of the cantilever beam structure is... and The natural circumferential frequency representing the torsional motion of the lens about the y-axis and the bending motion about the x-axis; The acquisition module includes a PSD sensor and an AD conversion chip, wherein, The PSD sensor is used to receive the laser reflected by the MEMS scanning mirror and convert the displacement of the reflected laser on the PSD sensor into a voltage signal of the PSD sensor. The AD conversion chip is used to receive and convert the voltage signal from the PSD sensor to obtain the displacement signal, and then transmit it to the main control chip. The driving module includes a signal generation unit, a power amplifier unit, and a main control chip, wherein, The signal generation unit is used to generate the raw drive signal for the MEMS scanning mirror; The power amplifier unit is used to amplify the original drive signal to the voltage required by the MEMS scanning mirror; and, The main control chip is used to calculate the actual maximum deflection angle of the MEMS scanning mirror within a preset time according to the optical path conversion formula. The signal generation unit generates the initial drive signal. ; The drive signal is output as a drive signal after passing through the power amplifier unit. ; The PSD sensor receives the reflected laser output and outputs a displacement signal. ; The PSD sensor was calibrated by recording the displacement of a fixed laser beam hitting the PSD sensor at different displacements, and the relationship between the displacement and the output voltage of the PSD sensor was obtained. The AD conversion chip acquires the displacement signal, and the main control chip calculates the actual deflection angle according to the optical path conversion formula. The calculation method of the optical path conversion formula is as follows: in The vertical distance between the scanning mirror surface and the PSD sensor. This represents the distance the light spot moves on the PSD sensor. The main control chip calculates the error between the actual maximum deflection angle of the two axes and the target maximum deflection angle. , The compensation angular frequency is calculated using a PI control algorithm. , ; The PI control algorithm is as follows: Where u(t) is the control signal output by the PI controller. It is the angle error value. It is a proportionality coefficient. It is the integration time constant; The signal generation unit receives the frequency control word from the main control chip and generates the drive signal. This drives the scanning mirror to operate normally in a resonant state.

2. The system according to claim 1, characterized in that, The main control chip is also used for, The error between the actual maximum deflection angle and the target maximum deflection angle is calculated using the PI algorithm to obtain a frequency control word, and the frequency control word is fed back to the signal generation unit. The signal generation unit is also used to update the original driving signal according to the frequency control word.

3. The system according to claim 1, characterized in that, The system also includes a power module. The power module is used to provide power to the MEMS scanning mirror, the acquisition module and the drive module.

4. A closed-loop control method for a resonant MEMS scanning mirror applied to the system described in claim 1, characterized in that, include: The original driving signal is acquired, and the MEMS scanning mirror is driven to receive and reflect the laser emitted by the laser source according to the original driving signal; Obtain the optical path information of the optical signal reflected by the MEMS scanning mirror; The actual maximum deflection angle of the MEMS scanning mirror is calculated based on the optical path information, and the original driving signal is updated based on the error value between the actual maximum deflection angle and the target maximum control deflection angle.

5. The method according to claim 4, characterized in that, The process of acquiring the optical path information of the optical signal reflected by the MEMS scanning mirror includes: The MEMS scanning mirror is reflected using a laser, and the displacement of the reflected laser light is converted into a voltage signal; and, The voltage signal is converted into a displacement signal.

6. The method according to claim 4, characterized in that, The calculation of the actual maximum deflection angle of the MEMS scanning mirror based on the optical path information includes: Acquire the raw drive signal of the MEMS scanning mirror; Amplify the original driving signal to the voltage required by the MEMS scanning mirror; and, The actual maximum deflection angle of the MEMS scanning mirror within a preset time is calculated based on the optical path conversion formula.

7. The method according to claim 4, characterized in that, The update of the original drive signal includes: The error value between the actual maximum deflection angle and the target maximum deflection angle is calculated using the PI algorithm to obtain the frequency control word, and the original drive signal is updated according to the frequency control word.

8. A computer device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the resonant MEMS scanning mirror closed-loop control method as described in any one of claims 4-7.

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