Piano automatic tuner and tuning method thereof

Abstract

The invention relates to the technical field of musical instrument maintenance, and discloses an automatic tuner for a piano and a tuning method of the automatic tuner. A tuning peg pin sleeve in the tuning peg pin adjusting device is sleeved with a tuning peg pin and rotates by matching visual calibration of a positioning camera and angle compensation of a motor with an electric telescopic rod, so that the problems that manual tuning depends on experience and the efficiency is low are solved; the intelligent decision-making module carries out grading processing according to intonation deviation, ensures tuning precision, and prevents teenagers from forming a wrong pitch concept due to long-term contact with misaligned keys. The self-adaptive learning module predicts a maintenance period by analyzing historical tuning data and prolongs the service life of the piano; the mobile intelligent terminal provides a visual interaction interface, the operation process is simplified, and the use cost is reduced. The device can automatically complete tuning, significantly improve tuning stability and timeliness, provide accurate intonation guarantee for teenager music learning, reduce manual maintenance frequency, and have both educational value and economic value.

Description

Technical Field

[0001] The present invention relates to the technical field of musical instrument maintenance, and particularly to a piano automatic tuner and a tuning method thereof. Background Art

[0002] The piano is known as the king of musical instruments and has extremely high musical performance. It is also the first choice for many teenagers to learn music art. Among them, piano tuning plays an important role in protecting the sense of pitch of teenagers, improving playing performance, extending the service life of the piano, maintaining stable sound quality, and increasing the value of the piano. Especially for teenagers, piano tuning is particularly important. The hearing of teenagers is more sensitive than that of adults, and it is the best period to establish the concept of pitch. If teenagers often play a piano with inaccurate pitch, it may form a wrong pitch concept, which may affect their future music learning and performance. In addition, for teenagers with the ability of "fixed pitch sense", if timely tuning is not carried out, it may affect their ability to directly identify pitch.

[0003] The essence of piano tuning is to calibrate the pitch by adjusting the string tension. The piano strings (one end is fixed to the cast iron plate, and the other end is wound around the tuning pin. The tuning pin is inserted into the pin hole of the cast iron plate, and the string tension is changed by rotating the pin. Traditional manual tuning requires the tuner to use a tuning wrench to hold the head of the tuning pin and judge the pitch deviation by hearing or an electronic device, and manually rotate for fine adjustment. This process depends on the experience of the technician and requires repeated turning of the tuning pin to adjust to the accurate pitch.

[0004] However, piano tuning is a very professional job and requires an experienced master for manual processing. It is not only time-consuming and laborious but also has a relatively high cost, bringing certain inconvenience to teenagers learning the piano. At present, there is no mature piano automatic tuning device on the market, and manual tuning has low efficiency and relies too much on the experience of technicians; for this reason, a piano automatic tuner and a tuning method thereof are proposed. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a piano automatic tuner and a tuning method thereof to solve the problems in the background art.

[0006] In a first aspect, to achieve the above object, the present invention provides the following technical solution: A piano automatic tuner, comprising:

[0007] A driving module, which is composed of an x-axis driving slide rail, a y-axis driving slide rail and a driving seat. The x-axis driving slide rail drives the y-axis driving slide rail to move horizontally, and the y-axis driving slide rail drives the driving seat to move vertically.

[0008] A tuning pin adjusting device, comprising:

[0009] A motor and an electric telescopic rod are installed on the driving seat. A rectangular block is fixedly installed at the output end of the motor. A sliding sleeve is slidably sleeved on the outer wall of the rectangular block. One end of the sliding sleeve is provided with a string shaft pin sleeve. A positioning camera is embedded and installed on the inner wall of the string shaft pin sleeve. The output end of the electric telescopic rod is fixedly connected with an adjusting plate. The adjusting plate is sleeved on the outer wall of the sliding sleeve. The sliding sleeve is rotatably connected with the adjusting plate;

[0010] A mobile intelligent terminal, which includes:

[0011] An audio acquisition and analysis module, which analyzes the vibration spectrum of the keys through Fourier transform (FFT);

[0012] A pitch deviation calculation module, which generates adjustment parameters based on the beat frequency analysis method;

[0013] A human-computer interaction interface, which displays a three-dimensional tuning track and a safety confirmation instruction;

[0014] A controller is installed on the driving seat and specifically includes:

[0015] A machine vision processing unit, which is connected to the positioning camera;

[0016] A motion control unit, which drives the driving module and the string shaft pin adjustment device;

[0017] A wireless communication module, which establishes a data channel with the mobile intelligent terminal and the positioning camera, and receives the adjustment parameters generated by the mobile intelligent terminal and the data detected by the positioning camera.

[0018] Preferably, the controller is provided with an angle calibration system, and its working process includes:

[0019] Obtain the end face image of the string shaft pin through the positioning camera and extract the edge feature points;

[0020] Calculate the axis deflection angle of the string shaft pin;

[0021] Obtain the axis deflection angle of the string shaft pin sleeve;

[0022] Calculate the difference between the axis deflection angle of the string shaft pin and the axis deflection angle of the string shaft pin sleeve, generate an angle compensation parameter, and drive the motor to perform axial alignment adjustment;

[0023] When θ ≤ θ1 (θ1 is the maximum vector included angle at which the string shaft pin sleeve can be sleeved on the string shaft pin), control the electric telescopic rod to push the string shaft pin sleeve to complete the sleeving;

[0024] When θ > θ1, drive the motor to finely adjust the rotation angle of the string shaft pin sleeve until θ ≤ θ1.

[0025] Preferably, the mobile intelligent terminal is provided with an intelligent decision-making module. When it detects that the pitch of the string is deviated, it automatically generates a decision tree including the following processing paths:

[0026] When the beat frequency difference < threshold, directly send a calibration instruction to the controller to perform automatic correction;

[0027] When the beat frequency difference ≥ threshold, trigger the human - machine interaction module to display a "Tuning Confirmation" interface;

[0028] When no confirmation instruction is received within the preset time, start the safety mode to automatically reset the string tension.

[0029] Preferably, the controller stores a database of the positions of the piano tuning pins. The mobile intelligent terminal reads the data in the database, and the database includes:

[0030] The two - dimensional coordinate mapping table of the tuning pins for each model of piano;

[0031] Historical tuning parameter records and an adaptive learning module.

[0032] Preferably, the electric telescopic rod is provided with a pressure feedback system, which includes:

[0033] A preset pressure threshold range [P min , P max ;

[0034] Real - time monitor the axial pressure value during the socketing process;

[0035] When P < P min , increase the propulsion speed. When P > P max , immediately stop and retract;

[0036] When P ∈ [P min , P max , maintain a constant - pressure propulsion mode.

[0037] Preferably, the adaptive learning module performs the following operations:

[0038] Record the amount of tension adjustment for each tuning;

[0039] Based on historical data, predict the trend of string tension attenuation and generate a recommended tuning period value;

[0040] When the actual tuning interval exceeds 1.2 times the recommended period, trigger the mobile intelligent terminal to send a maintenance reminder.

[0041] Preferably, the intelligent decision - making module is provided with a learning and optimization function and performs the following operations:

[0042] Dynamically adjust the threshold range according to the historical tuning success rate:

[0043] The initial threshold is set to 0.5 Hz;

[0044] When the success rate of tuning is ≥90% for 10 consecutive times, the threshold is relaxed to 0.6 Hz;

[0045] When the success rate of tuning is <80% for 5 consecutive times, the threshold is tightened to 0.4 Hz;

[0046] Automatically mark the strings with high-frequency deviation and generate a priority tuning queue.

[0047] In a second aspect, a tuning method for a piano automatic tuner, based on the piano automatic tuner described in the first aspect, the specific tuning method includes the following steps:

[0048] S1. Initialize positioning

[0049] Load the pre-stored coordinate data of the piano string axle pins;

[0050] Drive the module to move to the safe starting position.

[0051] As a further improvement of the above technical solution:

[0052] Move the smart terminal to collect audio signals;

[0053] Extract the fundamental frequency and calculate the deviation value Δf from the standard frequency.

[0054] Automatically generate a fine-tuning instruction;

[0055] If 0.5 Hz < |Δf| ≤ 1.5 Hz, the tuning needs to be confirmed by the user before execution;

[0056] If |Δf| > 1.5 Hz, lock the device and prompt for manual intervention.

[0057] Calibrate the angle of the string axle pin sleeve;

[0058] When the angle deviation ≤, trigger the socket operation.

[0059] Until the deviation ≤ 0.1 Hz.

[0060] S6. Data recording and maintenance reminder

[0061] Store the tuning parameters of this time;

[0062] Predict the next tuning time according to the historical data.

[0063] Preferably, step S3 adopts a progressive adjustment strategy:

[0064] The first adjustment amount is 100% of the theoretical value;

[0065] If not up to the standard, the subsequent adjustment amounts are halved successively;

[0066] The maximum number of adjustments does not exceed 3 times.

[0067] Preferably, the abnormal handling process is included in step S6:

[0068] When the single string fails to be tuned three times continuously, it is marked as abnormal and locked;

[0069] Generate a tuning report, including deviation correction records and equipment status scores.

[0070] Compared with the prior art, the present invention has the following beneficial effects:

[0071] The present invention accurately locates the coordinates of the tuning pin through the driving module. The tuning pin sleeve in the tuning pin adjusting device uses positioning camera vision calibration and motor angle compensation to cooperate with the electric telescopic rod to complete the socket connection with the tuning pin and the rotation of the tuning pin, solving the problems of manual tuning relying on experience and low efficiency; the intelligent decision-making module processes according to the pitch deviation classification to ensure the tuning accuracy and avoid teenagers forming wrong pitch concepts due to long-term contact with out-of-tune keys; the adaptive learning module predicts the maintenance period by analyzing historical tuning data, extending the service life of the piano; the mobile intelligent terminal provides a visual interaction interface, simplifying the operation process and reducing the use cost. This device can automatically complete tuning, significantly improving the tuning stability and timeliness, providing accurate pitch guarantee for teenagers' music learning, reducing the manual maintenance frequency at the same time, and having both educational value and economic value.

[0072] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained by the structures pointed out in the specification, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0074] Figure 2 is a schematic diagram of the structure of the tuning pin adjusting device of the present invention;

[0075] Figure 3 is a cross-sectional structure diagram of the sliding sleeve and the tuning pin sleeve of the present invention;

[0076] Figure 4 is a flowchart of the tuning method of the piano automatic tuner of the present invention;

[0077] Figure 5 is a control block diagram of the piano automatic tuner of the present invention.

[0078] In the figure: 1. Driving module; 11. X-axis driving slide rail; 12. Y-axis driving slide rail; 13. Driving seat; 2. Tuning peg adjusting device; 21. Motor; 22. Electric telescopic rod; 23. Sliding sleeve; 24. Tuning peg sleeve; 25. Adjusting plate; 26. Positioning camera; 27. Rectangular block; 3. Controller; 4. Mobile intelligent terminal. Specific embodiments

[0079] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0080] Please refer to Figures 1-5 , a piano automatic tuner and its tuning method in the present invention include the following:

[0081] Embodiment 1: Conventional tuning

[0082] Device configuration:

[0083] The driving module 1 is composed of an x-axis driving slide rail 11, a y-axis driving slide rail 12, and a driving seat 13. The x-axis driving slide rail 11 drives the y-axis driving slide rail 12 to move horizontally, and the y-axis driving slide rail 12 drives the driving seat 13 to move vertically. The driving seat 13 carries the tuning peg adjusting device 2, and the driving module 1 drives the tuning peg adjusting device 2 to move.

[0084] The tuning peg adjusting device 2 includes:

[0085] A motor 21 and an electric telescopic rod 22 installed on the driving seat 13. A rectangular block 27 is fixedly installed at the output end of the motor 21. A sliding sleeve 23 is slidably sleeved on the outer wall of the rectangular block 27. A tuning peg sleeve 24 is installed at one end of the sliding sleeve 23. A positioning camera 26 is embedded and installed on the inner wall of the tuning peg sleeve 24. The output end of the electric telescopic rod 22 is fixedly connected to an adjusting plate 25. The adjusting plate 25 is sleeved on the outer wall of the sliding sleeve 23. The sliding sleeve 23 is rotatably connected to the adjusting plate 25. The driving module 1 adjusts the tuning peg sleeve 24 to the corresponding position of the tuning peg to be adjusted. The positioning camera 26 detects the angle of the tuning peg, and drives the rectangular block 27 through the motor 21, so that the sliding sleeve 23 drives the tuning peg sleeve 24 to rotate to the corresponding angle of the tuning peg. At this time, the electric telescopic rod 22 works, and then drives the sliding sleeve 23 to slide on the outer wall of the rectangular block 27 through the adjusting plate 25 until the tuning peg sleeve 24 is sleeved on the outer wall of the tuning peg. At this time, the motor 21 can be driven to rotate the tuning peg sleeve 24, thereby rotating the tuning peg and adjusting the tension of the string to make its pitch accurate.

[0086] Mobile intelligent terminal 4: Install a dedicated APP to display the tuning trajectory in real time.

[0087] Controller 3: Store the two-dimensional coordinate mapping table of "Steinway Model D".

[0088] Operation process:

[0089] 1. Initialization and positioning:

[0090] The user selects the piano model, and the controller 3 loads the two-dimensional coordinates of the tuning pins.

[0091] The drive module 1 is reset to the safe coordinates (X = 0, Y = 0).

[0092] 2. Audio acquisition and analysis:

[0093] For example: When the user triggers the A4 key, the mobile intelligent terminal 4 acquires the audio signal.

[0094] The intelligent decision-making module determines that: After FFT analysis, the fundamental frequency is 440.5 Hz, calculates the beat frequency difference Δf = |440.5 - 440| = 0.5 Hz, and automatically sends an instruction to the controller 3.

[0095] 3. Deviation classification and instruction generation:

[0096] Δf = 0.5 Hz triggers automatic fine-tuning:

[0097] Generate instruction: X A4 , Y A4 (the coordinates corresponding to the A4 key's tuning pin), rotate counterclockwise by 10°.

[0098] 4. Positioning and calibration:

[0099] The drive module 1 controls the movement of the tuning pin sleeve 24 to X A4 , Y A4 .

[0100] The positioning camera 26 detects the image of the end face of the tuning pin, calculates the deflection angle of the tuning pin axis and the deflection angle of the tuning pin sleeve 24 axis θ = θ n °, and the controller 3 controls the motor 21 to work to adjust the angle of the tuning pin sleeve 24 so that the deflection angle of the tuning pin axis and the deflection angle of the tuning pin sleeve 24 axis θ ≤ θ1 (θ1 is the maximum vector angle at which the tuning pin sleeve 24 can be sleeved outside the tuning pin).

[0101] Trigger the electric telescopic rod 22 to push forward, and the pressure value stabilizes at P n (preset interval [P min ≤ P n

[0102] ≤ P max]), so that the string axis pin sleeve 24 is sleeved on the outer wall of the string axis pin to be adjusted.

[0103] 5. Tension adjustment and verification:

[0104] The motor 21 rotates counterclockwise by 10°, and the string axis pin sleeve 24 drives the string axis pin to rotate. After tuning, Δf=0.1 Hz is re-measured.

[0105] Data recording and maintenance reminder:

[0106] Storage parameters: The tuning tension adjustment value for this time is Δf = 0.5 → 0.1 Hz, which takes 2 minutes.

[0107] 6. Analysis of adaptive learning modules:

[0108] For decay prediction, consider the following:

[0109] The string tension will decay over time due to factors such as material fatigue, temperature and humidity changes;

[0110] Long-term data shows that the stability of the strings gradually decreases with use, and the tuning interval needs to be gradually extended; verification data example (based on historical tuning records):

[0111]

[0112] Implementation Logic

[0113] Data collection:

[0114] Record the final deviation (Δf), ambient temperature and humidity, and frequency of use for each tuning.

[0115] Parameter correction:

[0116] If the actual tuning period deviates from the predicted value by more than 10%, the coefficient is adjusted in proportion to the error (eg, 0.05→0.048 or 0.052).

[0117] Non-linear expansion:

[0118] When the data accumulation exceeds 100 times, it automatically switches to the exponential model:

[0119] T next =T last ·e kΔt (k=0.04~0.06)

[0120] Among them, T last is the last tuning cycle, and Δt is the time change factor.

[0121] Laboratory test: Under constant temperature and humidity conditions, it was measured that the tension of a typical piano string decays by about 3%-7% per month, and the middle value of 5% is taken as the benchmark.

[0122] Actual data fitting: Analysis of the tuning records of 100 pianos revealed that the tuning interval needed to be extended by 4.5%-5.5% per month on average.

[0123] Therefore, based on the formula T next =T last ×(1+0.05Δt) is calculated, and the next tuning time is predicted to be xx days later. After xx days, a message is pushed to the mobile smart terminal 4 to remind maintenance;

[0124] Maintenance reminder: When the user fails to tune the guitar for more than 42 days (more than 35×1.2), a message is pushed to the mobile smart terminal 4: "Risk of string tension attenuation, it is recommended to tune the guitar immediately."

[0125] Example 2: Dynamic Threshold Adjustment and Exception Handling

[0126] Scenario: Fluctuations in the historical tuning success rate trigger threshold adjustments.

[0127] Operation process:

[0128] Initial threshold setting:

[0129] The initial threshold is 0.5Hz. After 10 consecutive tunings with a success rate of 95%, the threshold is automatically relaxed to 0.6Hz.

[0130] Tuning execution:

[0131] Detect Δf=0.6Hz (≤ new threshold 0.6Hz) and automatically generate adjustment instructions.

[0132] According to the progressive strategy: the first adjustment is 100% (rotation 12°), and the re-measurement is Δf=0.3Hz.

[0133] Exception handling:

[0134] If a string fails to be tuned three times in a row (Δf=1.2Hz→1.0Hz→1.1Hz), the system will lock the string.

[0135] Generate a report: Annotate "Abnormal String B2" and give the device a score of 70 (out of 100).

[0136] Example 3: Adaptive learning and maintenance prediction

[0137] Long-term data:

[0138] History Records: The last five tuning intervals were 30 days, 35 days, 40 days, 38 days, and 42 days.

[0139] After analysis, the adaptive learning module recommends a tuning cycle of 40 days.

[0140] Operation process:

[0141] Overdue maintenance trigger:

[0142] When the actual tuning interval reaches 50 days (more than 1.25 times the recommended period), the mobile intelligent terminal 4 pops up a maintenance reminder.

[0143] Full-piano tuning execution:

[0144] After completing the tuning of 88 keys, the average Δf drops from 0.8 Hz to 0.2 Hz.

[0145] Data update:

[0146] Update the two-dimensional coordinate mapping table to compensate for the environmental deformation error of 0.2 mm.

[0147] Predict that the next tuning period is 45 days and push it to the user.

[0148] Summary of the embodiment:

[0149] This embodiment fully implements the technical solution of the claim book. By driving the module 1 to accurately locate the coordinates of the tuning pin, the tuning pin sleeve 24 in the tuning pin adjusting device 2 uses the visual calibration of the positioning camera 26 and the angle compensation of the motor 21 to cooperate with the electric telescopic rod 22 to complete the socket connection with the tuning pin. The mobile intelligent terminal 4 makes hierarchical decisions based on the beat frequency difference. The controller 3 calls the two-dimensional coordinate database and drives the electric telescopic rod 22 to safely advance within the pressure feedback interval. At the same time, the adaptive learning module analyzes the historical tuning data (such as the tension adjustment amount, environmental temperature), predicts the tuning period through the linear attenuation model, triggers a maintenance reminder when it exceeds 1.2 times, locks the strings and generates a diagnostic report if the continuous tuning fails. The whole process covers the links of initialization, analysis, adjustment, verification and data optimization, realizing automatic tuning and tuning reminder.

Claims

1. An automatic piano tuner, characterized in that: include: The driving module (1) is composed of an x-axis driving rail (11), a y-axis driving rail (12) and a driving seat (13); the x-axis driving rail (11) drives the y-axis driving rail (12) to move horizontally, and the y-axis driving rail (12) drives the driving seat (13) to move vertically. The string axis pin adjusting device (2) comprises: A motor (21) and an electric telescopic rod (22) are mounted on a driving seat (13); a rectangular block (27) is fixedly mounted on the output end of the motor (21); a sliding sleeve (23) is provided on the outer wall of the rectangular block (27); a string axis pin sleeve (24) is mounted on one end of the sliding sleeve (23); a positioning camera (26) is embedded in the inner wall of the string axis pin sleeve (24); an adjusting plate (25) is fixedly connected to the output end of the electric telescopic rod (22); the adjusting plate (25) is sleeved on the outer wall of the sliding sleeve (23); and the sliding sleeve (23) is rotatably connected to the adjusting plate (25); A mobile intelligent terminal (4), comprising: Audio acquisition and analysis module, which analyzes the vibration spectrum of the piano keys through Fourier transform (FFT); The pitch deviation calculation module generates adjustment parameters based on the beat frequency analysis method; Human-computer interaction interface, showing three-dimensional tuning trajectory and safety confirmation instructions; The controller (3) is mounted on the driving seat (13), and specifically comprises: A machine vision processing unit connected to a positioning camera (26); A motion control unit drives the driving module (1) and the string axis pin adjustment device (2); The wireless communication module establishes a data channel with the mobile intelligent terminal (4) and the positioning camera (26), and receives adjustment parameters generated by the mobile intelligent terminal (4) and data detected by the positioning camera (26).

2. The automatic piano tuner according to claim 1, characterized in that: The controller (3) is provided with an angle calibration system, the working process of which includes: Acquire the end surface image of the chord pin by positioning the camera (26) and extract edge feature points; Calculate the axis deflection angle of the chord pin; Obtaining the axis deflection angle of the string axis pin sleeve (24); Calculating the difference between the axis deflection angle of the chord pin and the axis deflection angle of the chord pin sleeve (24), generating an angle compensation parameter, and driving the motor (21) to perform axial alignment adjustment; When θ≤θ1 (θ1 is the maximum vector angle at which the chord axis pin sleeve (24) can be sleeved outside the chord axis pin), the electric telescopic rod (22) is controlled to push the chord axis pin sleeve (24) to complete the sleeve connection; When θ>θ1, the driving motor (21) fine-tunes the rotation angle of the string axis pin sleeve (24) until θ≤θ1.

3. The automatic piano tuner according to claim 1, characterized in that: The mobile intelligent terminal (4) is provided with an intelligent decision-making module, which automatically generates a decision tree including the following processing paths when a string pitch deviation is detected: When the beat frequency difference is less than the threshold value, a calibration instruction is directly sent to the controller (3) to perform automatic correction; When the beat frequency difference is ≥ the threshold, the human-computer interaction module is triggered to display the "Do you want to tune" confirmation interface; If no confirmation command is received within the preset time, the safety mode is activated to automatically reset the string tension.

4. The automatic piano tuner according to claim 1, characterized in that: The controller (3) stores a piano string axis pin position database, and the mobile intelligent terminal (4) reads the database data, and the database includes: Two-dimensional coordinate mapping table of the string pins of various piano models; Historical tuning parameter recording and adaptive learning module.

5. The automatic piano tuner according to claim 1, characterized in that: The electric telescopic rod (22) is provided with a pressure feedback system, which comprises: Preset pressure threshold interval [P min ,P max ]; Real-time monitoring of the axial pressure value during the sleeve connection process; When P<P min When P>P max Stop immediately and retreat; In P∈[P min ,P max ] interval to maintain constant pressure propulsion mode.

6. The automatic piano tuner according to claim 4, characterized in that: The adaptive learning module performs the following operations: Record the tension adjustment for each tuning; Predict the string tension attenuation trend based on historical data and generate tuning cycle recommendations; When the actual tuning interval exceeds 1.2 times the recommended period, the mobile intelligent terminal (4) is triggered to send a maintenance reminder.

7. The automatic piano tuner according to claim 3, characterized in that: The intelligent decision-making module is provided with a learning optimization function, and performs the following operations: Dynamically adjust the threshold range based on the historical tuning success rate: The initial threshold was set at 0.5 Hz; When the tuning success rate is ≥90% for 10 consecutive times, the threshold is relaxed to 0.6Hz; When the tuning success rate is less than 80% for 5 consecutive times, the threshold is tightened to 0.4Hz; Automatically mark high frequency deviation strings and generate a priority tuning queue.

8. A tuning method for an automatic piano tuner, characterized in that: A piano automatic tuner according to any one of claims 1 to 7, wherein the specific tuning method comprises the following steps: S1. Initialization positioning Load the pre-stored piano string axis pin coordinate data; The drive module (1) moves to a safe starting position. S2. Audio Collection and Analysis After the user triggers the piano key, the mobile intelligent terminal (4) collects the audio signal; Extract the fundamental frequency and calculate the deviation Δf from the standard frequency. S3. Deviation classification and instruction generation If |Δf|≤0.5Hz, fine-tuning instructions are automatically generated; If 0.5Hz<|Δf|≤1.5Hz, the tuning will be performed after user confirmation; If |Δf|>1.5Hz, the device will be locked and prompt for manual intervention. S4. Positioning and calibration The driving module (1) moves to a target chord pin position; A positioning camera (26) detects an end surface image of a chord pin and calibrates an angle of a chord pin sleeve (24); When the angle deviation is ≤θ1, the socketing operation is triggered. S5. Tension adjustment and verification Controlling the motor (21) to rotate and adjust the string tension; After tuning, recheck Δf until the deviation is ≤ 0.1Hz. S6.Data recording and maintenance reminder Store the tuning parameters for this time; Predict the next tuning time based on historical data.

9. The tuning method of an automatic piano tuner according to claim 8, characterized in that: Step S3 adopts a progressive adjustment strategy: The first adjustment amount is 100% of the theoretical value; If the target is not met, the subsequent adjustment amount will be halved; The maximum number of adjustments is no more than 3 times.

10. The tuning method of an automatic piano tuner according to claim 8, characterized in that: Step S6 includes the exception handling process: When a single string fails to tune three times in a row, it is marked as abnormal and locked; Generate tuning report including deviation correction record and equipment status score.

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