MCU-based pitch signaling module for adjustable pitch propeller and static calibration method

Abstract

The present application relates to the technical field of ship controllable pitch propeller, and provides a pitch signaling module and static calibration method of controllable pitch propeller based on MCU, aiming at solving the deficiencies of traditional mechanical calibration and analog signal calibration method.The system comprises an MCU control unit, a potentiometer sensor unit, a setting and fine tuning control unit, a signal output unit, a storage unit and an indication and display unit.The MCU reads the potentiometer output signal in real time, combines the preset algorithm and calibration data, and realizes the setting and fine tuning of high-precision pitch feedback signal.The method is operated by buttons and dial switches, simplifies the calibration process, improves the calibration accuracy and efficiency, and is suitable for ship controllable pitch propeller system and other fields requiring high-precision feedback calibration.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ship controllable pitch propeller, and particularly relates to a controllable pitch propeller pitch signaling module based on an MCU and a static calibration method. BACKGROUND

[0002] Controllable pitch propeller systems are widely used in ships and aircrafts. By changing the angle of the propeller blades, the system can adjust the thrust to achieve more efficient power transmission and control performance. In these systems, pitch signaling is a key technology for monitoring and controlling the angle of the ship propeller (pitch). It is necessary to ensure that the feedback signal has sufficient accuracy and stability. However, due to the long-term use of these systems, certain drift and errors may occur.

[0003] Therefore, the feedback calibration of controllable pitch propeller pitch signaling is a key link to ensure the accurate and reliable operation of the ship controllable pitch propeller system. The existing technology often uses mechanical calibration methods and analog signal calibration methods.

[0004] The mechanical calibration method is a traditional calibration method widely used in early controllable pitch propeller systems. This method adjusts mechanical components to make the system output corresponding signals at different pitch positions, thereby achieving calibration. The specific scheme is as follows: when the pitch is at -100%, 0%, and 100% positions, mechanical reference points are set respectively. These reference points are usually determined by mechanical limit switches or physical markers. The operator manually adjusts the controllable pitch propeller to these reference points and records the corresponding signal output (such as voltage, current value). Then adjust the length or position of the connecting rod to ensure that the signal value at each reference point is consistent with the expected value. It needs to be adjusted and tested repeatedly until the desired accuracy is achieved. Although this method has certain simplicity and directness, it has obvious shortcomings in precision, stability, and maintenance. The adjustment and calibration process is time-consuming and labor-intensive and needs frequent maintenance.

[0005] The analog signal calibration method uses a standard signal source (such as a precision voltage source or current source) to generate known analog signals, for example, 4mA, 12mA, and 20mA current signals at pitch positions of -100%, 0%, and 100% respectively. Then input the reference signal into the system and measure the output signal of the system at these reference points. Adjust the gain and offset circuits inside the system, such as using a potentiometer to correct the system error, to ensure that the error is within an acceptable range. The output after adjustment is consistent with the reference signal.

[0006] The accuracy of the reference signal source limits the calibration of analog signals, and any slight error in the reference signal source will affect the calibration results. Environmental changes such as temperature and humidity will also affect the stability of analog signals, resulting in unstable calibration results. Precise signal sources and measurement equipment are required, and the operation is complex and time-consuming. Repeated measurements and adjustments are required, increasing workload and time costs. The hardware adjustment method cannot respond to system changes in real time and has a delay. SUMMARY

[0007] To solve the problems in the background art, the present application provides a pitch signaling module based on MCU for adjusting the pitch of a propeller, which includes an MCU control unit and a potentiometer sensor unit, a setting and fine-tuning control unit, a signal output unit, a storage unit, and an indication and display unit connected in communication with the MCU control unit, wherein:

[0008] The MCU control unit performs signal reading, processing, storage, and output control during the entire calibration process, reads the voltage or current signal output by the potentiometer in real time, or receives the feedback signal of the communication output type potentiometer through the RS485 interface, and calculates the pitch feedback signal and controls the output according to the preset algorithm and stored calibration data;

[0009] The potentiometer sensor unit includes one or more of a resistance type potentiometer, a current output type potentiometer, and a communication output type potentiometer;

[0010] The setting and fine-tuning control unit includes manual operation components such as keys and dial switches, and is provided with a setting mode and a fine-tuning mode. The preliminary correspondence between the pitch position and the potentiometer output value is established by operating the setting mode. The pitch feedback signal is finely adjusted by operating the fine-tuning mode, so that the output of the pitch signaling signal remains consistent with the actual pitch position;

[0011] The signal output unit includes a current output module and a communication interface. The current output module outputs two-way pitch feedback current in real time according to the control of the MCU. The communication interface sends the communication amount of the pitch feedback current or other calibration related information;

[0012] The storage unit is located inside the MCU and includes an on-chip Flash, which stores various data generated during the calibration process, including pitch curve reference points, voltage or current offset amounts;

[0013] The indication and display unit includes LED indicator lights and OLED screen display components, which indicate different states and key information during the calibration process.

[0014] In the preferred scheme, the MCU control unit is connected with the potentiometer sensor unit through a signal line, receives the voltage, current signal output by the potentiometer or receives the communication signal through the RS485 interface; the MCU control unit is connected with the buttons and the DIP switch of the setting and fine-tuning control unit through the GPIO interface, receives the operation instruction to enter the setting or fine-tuning mode, and reads the button input value for the calibration operation. The MCU control unit is connected with the signal output unit current output module through the control line, controls the output of two 4-20mA pitch feedback currents; at the same time, the pitch feedback current or other calibration related information is sent through the communication interface. The MCU control unit directly accesses the storage unit Flash, reads the stored calibration data, and updates the stored data during the calibration process. The MCU control unit is connected with the indication and display unit through the GPIO interface or the I2C / SPI communication protocol, controls the state of the LED indicator light and the display content of the OLED screen.

[0015] In the preferred scheme, the resistance type potentiometer provides a resistance value varying with the pitch position, and outputs a corresponding voltage signal after being powered by an external power supply; the current output type potentiometer directly outputs a 4-20mA current signal proportional to the pitch position; the communication output type potentiometer outputs the communication amount of the pitch feedback signal through the RS485 interface.

[0016] In the preferred scheme, in the setting mode of the setting and fine-tuning control unit, the operator adjusts the pitch propeller to the three reference positions of full astern, zero pitch and full ahead by the buttons, and triggers the setting operation; in the fine-tuning mode, the pitch feedback signal is fine-tuned by the buttons through the DIP switch switched to the fine-tuning mode.

[0017] The static calibration method of the pitch signaling module of the pitch propeller based on the MCU is performed according to the following steps:

[0018] S1, system preparation:

[0019] Ensure that the pitch propeller system is in a calibratable state, and all components of the pitch signaling module of the pitch propeller based on the MCU are correctly connected and normally work;

[0020] Start the calibration system, initialize the MCU and other related hardware, and prepare to enter the calibration process;

[0021] S2, setting process:

[0022] S21: adjust the pitch position

[0023] Adjust the mechanical pitch of the pitch propeller to the three key reference points of full astern, i.e. -100% pitch position, zero pitch, i.e. 0% pitch position, and full ahead, i.e. +100% pitch position;

[0024] S22: read the output value of the potentiometer

[0025] At each reference point, the MCU reads the output value of the potentiometer, which is a resistance type, a current output type or a communication output type;

[0026] For a resistance type potentiometer, the MCU reads its output voltage value; for a current output type potentiometer, the MCU directly reads the current value or converts it to a voltage value through a high-precision resistor; for a communication output type potentiometer, the MCU reads the communication amount through an RS485 interface;

[0027] S23: Store reference point data

[0028] Store the read potentiometer output value as the reference point data of the pitch curve in the storage unit Flash of the MCU;

[0029] S24: Confirm that the setting is complete

[0030] Confirm that all reference point data has been correctly stored and check to ensure that there are no errors or abnormalities;

[0031] S3, fine tuning process:

[0032] S31: Enter fine tuning mode

[0033] Switch to fine tuning mode through the DIP switch, and prepare to finely adjust the pitch feedback signal;

[0034] S32: Select fine tuning pitch position

[0035] Select one or more of the +100%, 0%, -100% pitch positions that need to be fine tuned through the buttons on the control unit;

[0036] S33: Fine tuning operation

[0037] At the selected pitch position, fine tune the pitch feedback signal through the plus and minus buttons on the control unit;

[0038] During fine tuning, the MCU updates the reference point value on the pitch curve in real time and stores the new calibration data;

[0039] S34: Confirm fine tuning results

[0040] After fine tuning is complete, check whether the fine tuning results meet the requirements to ensure the accuracy and consistency between the output of the pitch signaling signal and the actual pitch position;

[0041] S4, calibration complete:

[0042] Confirm that the setting and fine tuning processes have been successfully completed, turn off the calibration system, and prepare to put the pitch adjusting system into normal use;

[0043] S5, monitoring and maintenance:

[0044] During normal operation of the system, the accuracy and stability of the pitch signaling signal are monitored regularly; if any abnormalities or drifts are found, the calibration process is started in real time for calibration.

[0045] The specific process of step S2 includes:

[0046] The setting and fine tuning control unit enters the pitch feedback signal setting mode by cyclically scanning the state of the dial switch. While the pitch feedback signal output function is still normally operating, the setting buttons for the +100%, 0%, and -100% pitch positions are detected for input. If the setting is confirmed, the current value of the potentiometer is sampled and assigned to the pitch curve reference point in the software, thereby realizing the feedback signal setting function. The value after assignment needs to be retained after power failure.

[0047] The MCU internal Flash stores values for deviation calibration based on external voltage and external current. Six input state registers are set in the Flash to store the following calibration data deviation amounts, including:

[0048] In the case of full reverse, i.e., 0V reference voltage input from the outside, the MCU control unit collects the corresponding voltage amount deviation;

[0049] In the case of zero pitch, i.e., 2.5V reference voltage input from the outside, the MCU control unit collects the corresponding voltage amount deviation;

[0050] In the case of full forward, i.e., 5V reference voltage input from the outside, the MCU control unit collects the corresponding voltage amount deviation;

[0051] In the case of full reverse, i.e., 4mA reference current input from the outside, the MCU control unit collects the corresponding current amount deviation;

[0052] In the case of zero pitch, i.e., 12mA reference current input from the outside, the MCU control unit collects the corresponding current amount deviation;

[0053] In the case of full forward, i.e., 20mA reference current input from the outside, the MCU control unit collects the corresponding current amount deviation.

[0054] The beneficial effects achieved by the present application are:

[0055] First, by adopting a system architecture including an MCU control unit, a potentiometer sensor unit, a setting and fine tuning control unit, a signal output unit, a storage unit, and an indication and display unit, the units are connected through signal lines or interfaces, realizing efficient data transmission and control.

[0056] Second, the MCU-based static calibration method of the application realizes a high-precision correspondence between the pitch position and the signaling signal. Compared with traditional mechanical calibration and analog signal calibration methods, this method can significantly improve calibration accuracy and reduce errors. The MCU control unit can read and process the voltage or current signal output by the potentiometer in real time, and calculate and control the feedback signal according to the preset algorithm and stored calibration data, thereby reducing the impact of environmental changes on system stability. This calibration method divides the calibration process into two steps: setting and fine-tuning, which can be completed manually through buttons and dial switches without the need for complex precision equipment and repeated adjustments, greatly simplifying the operation process.

[0057] Third, the application uses digital signal processing technology, and the MCU can process input signals and correct them in real time, quickly respond to system changes, reduce adjustment time and workload, and reduce operation difficulty and time cost. The application of MCU enables the system to read and process signals in real time, ensuring the real-time nature of calibration. Compared with hardware adjustment methods, there is no delay problem. The method of the application is not only suitable for ship controllable pitch propeller systems, but also can be extended to other fields that require high-precision feedback calibration, and has wide application prospects and potential market value. During normal operation of the system, the accuracy and stability of the pitch signaling signal can be monitored regularly, and once abnormalities or drifts are found, the calibration process can be started in real time for calibration, improving the maintainability and reliability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0058] Figure 1 is the overall system structure diagram of the application;

[0059] Figure 2 is a software offset calculation and storage process diagram in the setting mode;

[0060] Figure 3 is a corresponding curve diagram of the controllable pitch propeller pitch signaling module output and the potentiometer output based on MCU. DETAILED DESCRIPTION

[0061] The technical solutions in the application will be described clearly and completely below with reference to the drawings in the application. In addition, the forms of each structure described in the following embodiments are only examples, and the application is not limited to each structure described in the following embodiments. All other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the application.

[0062] REFERENCE Figures 1-2The application provides a pitch signaling module based on MCU, which comprises an MCU control unit and a potentiometer sensor unit, a setting and fine tuning control unit, a signal output unit, a storage unit and an indication and display unit connected with the MCU control unit.

[0063] The MCU control unit performs signal reading, processing, storage and output control in the whole calibration process, reads the voltage or current signal output by the potentiometer in real time, or receives the feedback signal of the communication output type potentiometer through the RS485 interface, and calculates the pitch feedback signal and controls the output according to the preset algorithm and the stored calibration data.

[0064] The potentiometer sensor unit comprises one or more of a resistance type potentiometer, a current output type potentiometer and a communication output type potentiometer.

[0065] The setting and fine tuning control unit comprises a key and a dial switch manual operation part, and is provided with a setting mode and a fine tuning mode, the preliminary corresponding relationship between the pitch position and the potentiometer output value is established through the setting mode operation, and the pitch feedback signal is finely adjusted through the fine tuning mode operation, so that the output of the pitch signaling signal is consistent with the actual pitch position.

[0066] The signal output unit comprises a current output module and a communication interface; the current output module outputs two pitch feedback currents in real time according to the control of the MCU; and the communication interface sends the communication amount of the pitch feedback current or other calibration related information.

[0067] The storage unit is located in the MCU and comprises an on-chip Flash, which stores various data generated in the calibration process, including the pitch curve reference point, the voltage amount or the current amount offset.

[0068] The indication and display unit comprises an LED indicator lamp and an OLED screen display part, which indicates different states and key information in the calibration process.

[0069] In the preferred scheme, the MCU control unit is connected with the potentiometer sensor unit through a signal line, receives the voltage, current signal output by the potentiometer or receives the communication signal through the RS485 interface; the MCU control unit is connected with the buttons and the DIP switch of the setting and fine-tuning control unit through the GPIO interface, receives the operation instruction to enter the setting or fine-tuning mode, and reads the button input value for the calibration operation. The MCU control unit is connected with the signal output unit current output module through the control line, controls the output of two 4-20mA pitch feedback currents; at the same time, the pitch feedback current or other calibration related information is sent through the communication interface. The MCU control unit directly accesses the storage unit Flash, reads the stored calibration data, and updates the stored data during the calibration process. The MCU control unit is connected with the indication and display unit through the GPIO interface or the I2C / SPI communication protocol, controls the state of the LED indicator light and the display content of the OLED screen.

[0070] In the preferred scheme, the resistance type potentiometer provides a resistance value varying with the pitch position, and outputs a corresponding voltage signal after being powered by an external power supply; the current output type potentiometer directly outputs a 4-20mA current signal proportional to the pitch position; the communication output type potentiometer outputs the communication amount of the pitch feedback signal through the RS485 interface.

[0071] In the preferred scheme, in the setting mode of the setting and fine-tuning control unit, the operator adjusts the pitch propeller to the three reference positions of full astern, zero pitch and full ahead by the buttons, and triggers the setting operation; in the fine-tuning mode, the pitch feedback signal is fine-tuned by the buttons through the DIP switch switched to the fine-tuning mode.

[0072] The static calibration method of the pitch signaling module of the pitch propeller based on the MCU is performed according to the following steps:

[0073] S1, system preparation:

[0074] Ensure that the pitch propeller system is in a calibratable state, and all components of the pitch signaling module of the pitch propeller based on the MCU are correctly connected and normally work;

[0075] Start the calibration system, initialize the MCU and other related hardware, and prepare to enter the calibration process;

[0076] S2, setting process:

[0077] S21: adjust the pitch position

[0078] Adjust the mechanical pitch of the pitch propeller to the three key reference points of full astern, i.e. -100% pitch position, zero pitch, i.e. 0% pitch position, and full ahead, i.e. +100% pitch position;

[0079] S22: read the output value of the potentiometer

[0080] At each reference point, the MCU reads the output value of the potentiometer, which is a resistance type, a current output type or a communication output type;

[0081] For a resistance type potentiometer, the MCU reads its output voltage value; for a current output type potentiometer, the MCU directly reads the current value or converts it to a voltage value through a high-precision resistor; for a communication output type potentiometer, the MCU reads the communication amount through an RS485 interface;

[0082] S23: Store reference point data

[0083] Store the read potentiometer output value as the reference point data of the pitch curve in the storage unit Flash of the MCU;

[0084] S24: Confirm that the setting is complete

[0085] Confirm that all reference point data has been correctly stored, and check to ensure that there are no errors or abnormalities;

[0086] S3, fine tuning process:

[0087] S31: Enter fine tuning mode

[0088] Switch to fine tuning mode through the DIP switch, and prepare to finely adjust the pitch feedback signal;

[0089] S32: Select fine tuning pitch position

[0090] Select one or more of the +100%, 0%, -100% pitch positions that need to be fine tuned through the buttons on the control unit;

[0091] S33: Fine tuning operation

[0092] At the selected pitch position, fine tune the pitch feedback signal through the plus and minus buttons on the control unit;

[0093] During fine tuning, the MCU updates the reference point value on the pitch curve in real time and stores the new calibration data;

[0094] S34: Confirm fine tuning results

[0095] After fine tuning is complete, check whether the fine tuning results meet the requirements to ensure the accuracy and consistency between the output of the pitch signaling signal and the actual pitch position;

[0096] S4, calibration complete:

[0097] Confirm that the setting and fine tuning processes have been successfully completed, turn off the calibration system, and prepare to put the pitch control system into normal use;

[0098] S5, monitoring and maintenance:

[0099] During normal operation of the system, the accuracy and stability of the pitch signaling is monitored periodically; if any abnormalities or drifts are found, a calibration process is initiated in real time to calibrate.

[0100] The specific process of step S2 includes:

[0101] The setting and fine tuning control unit enters the pitch feedback signal setting mode by cyclically scanning the state of the dial switch. While the pitch feedback signal output function is still in normal operation, the setting buttons for the +100%, 0%, and -100% pitch positions are detected for input. If the setting is confirmed, the current value of the potentiometer is sampled and assigned to the pitch curve reference point in the software, thereby realizing the feedback signal setting function. The value after assignment needs to be retained after power failure.

[0102] The MCU on-chip Flash stores the values for deviation calibration based on external voltage and external current. Six input state registers are set in the Flash to store the following calibration data deviation, including:

[0103] In the case of full reverse, i.e. 0V reference voltage input externally, the MCU control unit collects the corresponding voltage deviation;

[0104] In the case of zero pitch, i.e. 2.5V reference voltage input externally, the MCU control unit collects the corresponding voltage deviation;

[0105] In the case of full forward, i.e. 5V reference voltage input externally, the MCU control unit collects the corresponding voltage deviation;

[0106] In the case of full reverse, i.e. 4mA reference current input externally, the MCU control unit collects the corresponding current deviation;

[0107] In the case of zero pitch, i.e. 12mA reference current input externally, the MCU control unit collects the corresponding current deviation;

[0108] In the case of full forward, i.e. 20mA reference current input externally, the MCU control unit collects the corresponding current deviation.

[0109] The embodiment 1 divides the static calibration process into two steps of setting and fine tuning. In the setting process, the mechanical pitch is adjusted to three positions of full reverse, zero pitch and full forward respectively. The software reads the potentiometer output values of the three positions. In any mode, the initial value of-100% should not be between 0% and +100%, the initial value of +100% should not be between-100% and 0%, and the initial value of 0% should not be outside-100% and +100%. The three values should not have two or more same values. Finally, the setting of the pitch feedback signals of the three positions of +100%, 0% and-100% is completed by pressing the buttons on the MCU-based pitch signaling module of the adjustable pitch propeller respectively.

[0110] In the initial pitch feedback signal reading process of the MCU-based pitch signaling module of the adjustable pitch propeller, the initial pitch feedback signals of three potentiometers are mainly collected, and the type of the actually collected pitch feedback signal is determined according to the actual potentiometer selection.

[0111] The resistance range of the resistance type potentiometer is 0-5KΩ. The MCU-based pitch signaling module of the adjustable pitch propeller provides 0-5V (DC) power source for the resistance type potentiometer, and the voltage value of the collected resistance is taken as the initial pitch feedback signal and read into the MCU-based pitch signaling module of the adjustable pitch propeller for subsequent setting.

[0112] The output range of the current output type potentiometer is 4-20mA. The MCU-based pitch signaling module of the adjustable pitch propeller directly reads the 4-20mA pitch feedback current, or indirectly reads the 4-20mA pitch feedback current signal after converting the current into a voltage signal through a high-precision resistor.

[0113] The communication output type potentiometer outputs the pitch feedback signal communication through RS485. The MCU-based pitch signaling module of the adjustable pitch propeller reads the pitch feedback communication by means of RS485 protocol.

[0114] After the MCU-based pitch signaling module software of the adjustable pitch propeller enters the pitch feedback signal setting function by cyclically scanning the state of the DIP switch, the pitch feedback signal output function is still normally running, while the software detects whether the setting buttons of the three pitch positions of +100%, 0% and-100% have input. If the setting is confirmed, the current value of the potentiometer is sampled and assigned to the pitch curve reference point in the software, so as to realize the feedback signal setting function. The value after assignment needs to be kept after power failure.

[0115] The MCU chip Flash stores the values deviated from the external voltage and external current for calibration. The types of calibration values include:

[0116] The MCU single-chip microcomputer collects the corresponding voltage offset under the condition of external input 0V reference voltage (full reverse); the MCU single-chip microcomputer collects the corresponding voltage offset under the condition of external input 2.5V reference voltage (zero pitch); the MCU single-chip microcomputer collects the corresponding voltage offset under the condition of external input 5V reference voltage (full forward); the MCU single-chip microcomputer collects the corresponding current offset under the condition of external input 4mA reference current (full reverse); the MCU single-chip microcomputer collects the corresponding current offset under the condition of external input 12mA reference current (zero pitch); the MCU single-chip microcomputer collects the corresponding current offset under the condition of external input 20mA reference current (full forward); and 6 input state registers are set in the Flash in the software to store the above calibration data offsets.

[0117] The pitch signaling module based on the MCU further needs to design an output pitch feedback signal fine-tuning function according to actual use needs, that is, the pitch signaling module based on the MCU is switched to the pitch feedback signal fine-tuning mode through a code switch, the first button is used to switch +100%, 0%, and -100% three fine-tuned pitch positions, and the second and third buttons are used to fine-tune three reference points on a curve corresponding the potentiometer output and the pitch signaling module based on the MCU in the form of addition and subtraction, so as to realize the feedback current fine-tuning function.

[0118] The feedback current fine-tuning function program scans the code switch, when the feedback current fine-tuning function is entered, the pitch signaling module based on the MCU sets the IO corresponding register, collects the input values of the three buttons in real time, and the OLED screen displays the current latest reference values of the full forward pitch, the full reverse pitch, and the pitch zero position.

[0119] Finally, before the pitch signaling module based on the MCU outputs the pitch feedback current, the main program reads the collected potentiometer voltage / current signals, calculates the pitch feedback current output value corresponding to the current potentiometer voltage / current value by means of the input / output corresponding relationship determined by the three points of full forward, full reverse, and pitch zero, and controls the current output module by the CPU of the pitch signaling module based on the MCU to output two paths of 4-20mA pitch feedback current in real time. Meanwhile, the pitch feedback current is sent in the form of RS485 communication.

[0120] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A MCU-based pitch control propeller pitch signaling module, characterized in that, It includes an MCU control unit and a potentiometer sensor unit, a setting and fine-tuning control unit, a signal output unit, a storage unit, and an indication and display unit that are communicatively connected to the MCU control unit, wherein: The MCU control unit performs signal reading, processing, storage, and output control throughout the calibration process. It reads the voltage or current signal output by the potentiometer in real time, or receives feedback signals from the communication output potentiometer via the RS485 interface. Based on the preset algorithm and stored calibration data, it calculates the pitch feedback signal and controls the output. The potentiometer sensor unit includes one or more of the following: resistive potentiometer, current output potentiometer, and communication output potentiometer; The setting and fine-tuning control unit includes manual operation components such as buttons and DIP switches. It is equipped with a setting mode and a fine-tuning mode. The setting mode operation establishes a preliminary correspondence between the pitch position and the potentiometer output value. The fine-tuning mode operation makes fine adjustments to the pitch feedback signal to ensure that the output of the pitch signal is consistent with the actual pitch position. The signal output unit includes a current output module and a communication interface; the current output module outputs two pitch feedback currents in real time according to the control of the MCU; the communication interface sends communication data such as pitch feedback current or other calibration-related information. The storage unit is located inside the MCU, including on-chip Flash, which stores various data generated during the calibration process, including pitch curve reference points, voltage or current offsets. The indicator and display unit includes LED indicator lights and an OLED screen display component, which indicate different states and key information during the calibration process; The MCU control unit is connected to the potentiometer sensor unit via signal lines, receiving voltage and current signals output by the potentiometer or communication signals via an RS485 interface. The MCU control unit connects to the buttons and DIP switches of the tuning and fine-tuning control unit via a GPIO interface, receiving operation commands to enter tuning or fine-tuning mode and reading button input values ​​for calibration. The MCU control unit connects to the current output module of the signal output unit via control lines, controlling its output of two 4-20mA pitch feedback currents. Simultaneously, it sends pitch feedback current or other calibration-related information via a communication interface. The MCU control unit directly accesses the Flash memory unit, reading stored calibration data and updating the stored data during calibration. The MCU control unit connects to the indicator and display unit via a GPIO interface or I2C / SPI communication protocol, controlling the status of LED indicators and the content displayed on the OLED screen.

2. The MCU-based pitch control propeller pitch transmission module according to claim 1, characterized in that: Resistive potentiometers provide a resistance value that varies with the pitch position and output a corresponding voltage signal after being powered by an external power supply; current output potentiometers directly output a 4-20mA current signal proportional to the pitch position; communication output potentiometers output the pitch feedback signal via an RS485 interface.

3. The MCU-based pitch control propeller pitch transmission module according to claim 1, characterized in that: In the setting mode of the setting and fine-tuning control unit, the operator adjusts the pitch control propeller to three reference positions—full reverse, zero pitch, and full forward—using buttons, and triggers the setting operation. In the fine-tuning mode, the operator switches to the fine-tuning mode via a DIP switch and fine-tunes the pitch feedback signal using buttons.

4. The static calibration method for the MCU-based pitch control propeller pitch transmitter module as described in any one of claims 1-3, characterized in that, Follow these steps: S1. System Preparation: Ensure that the controllable pitch propeller system is in a calibrable state and that all components of the MCU-based controllable pitch propeller pitch signaling module are correctly connected and functioning properly; Start the calibration system, initialize the MCU and other related hardware, and prepare to enter the calibration process; S2, Tuning process: S21: Adjust the pitch position The mechanical pitch of the controllable pitch propeller is adjusted to three key reference points: full reverse (-100% pitch), zero pitch (0% pitch), and full forward (+100% pitch). S22: Read potentiometer output value At each reference point, the MCU reads the output value of the potentiometer, which can be resistive, current-output, or communication-output type. For resistive potentiometers, the MCU reads their output voltage value; for current output potentiometers, the MCU directly reads the current value or converts it to a voltage value through a high-precision resistor; for communication output potentiometers, the MCU reads the communication signal through an RS485 interface. S23: Store reference point data The potentiometer output value read is used as the reference point data of the pitch curve and stored in the MCU's Flash memory. S24: Confirm tuning complete Confirm that all benchmark data has been stored correctly and check to ensure there are no errors or anomalies; S3, Fine-tuning process: S31: Enter fine-tuning mode Switch to fine-tuning mode using the DIP switch to prepare for precise adjustment of the pitch feedback signal; S32: Select the fine-tuning pitch position Select the pitch position to be fine-tuned, i.e., one or more of +100%, 0%, and -100%, using the buttons on the control unit; S33: Perform fine-tuning operations At the selected pitch position, the pitch feedback signal can be finely adjusted using the plus and minus buttons on the control unit; During the fine-tuning process, the MCU updates the reference point value on the pitch curve in real time and stores the new calibration data; S34: Confirm the fine-tuning results After fine-tuning, check whether the fine-tuning results meet the requirements to ensure the accuracy and consistency between the output of the pitch signal and the actual pitch position; S4. Calibration complete: After confirming that the setting and fine-tuning processes have been successfully completed, shut down the calibration system and prepare to put the controllable pitch propeller system into normal use. S5. Monitoring and Maintenance: During normal system operation, the accuracy and stability of the pitch signal should be monitored regularly; if any abnormality or drift is detected, the calibration process should be initiated in real time for calibration.

5. The method according to claim 4, characterized in that, The specific process of step S2 includes: The setting and fine-tuning control unit enters the pitch feedback signal setting mode by cyclically scanning the DIP switch status. While the pitch feedback signal output function is still operating normally, it detects whether there is input to the setting buttons at the three pitch positions of +100%, 0%, and -100%. If the setting is confirmed, the current value of the sampling potentiometer is assigned to the pitch curve reference point in the software, thereby realizing the feedback signal setting function. The assigned value needs to be retained after power failure. The MCU's on-chip Flash stores the offset calibration values ​​based on external voltage and current; six input status registers are set in the Flash to store the following calibration data offsets, including: When the external input reference voltage is 0V, the vehicle is in full reverse mode, and the MCU control unit collects the corresponding voltage offset. With an external input reference voltage of 2.5V (zero pitch), the MCU control unit acquires the corresponding voltage offset. When the external input reference voltage is 5V, the vehicle is fully oriented, and the MCU control unit collects the corresponding voltage offset. When an external reference current of 4mA is input, the vehicle is in full reverse mode, and the MCU control unit collects the corresponding current offset. With an external input of 12mA reference current (i.e., zero pitch), the MCU control unit acquires the corresponding current offset. When the external input reference current is 20mA, the vehicle is in full forward position, and the MCU control unit collects the corresponding current offset.

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