Controllable-pitch propeller pitch signaling module based on MCU and static calibration method

Abstract

The invention relates to the technical field of ship controllable-pitch propellers, provides an MCU-based controllable-pitch propeller pitch signaling module and a static calibration method, and aims to overcome the defects of traditional mechanical calibration and analog signal calibration methods. 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. Output signals of the potentiometers are read in real time through the MCU, and setting and fine tuning of high-precision screw pitch feedback signals are achieved in combination with a preset algorithm and calibration data. According to the method, through operation of the key and the dial switch, the calibration process is simplified, the calibration precision and efficiency are improved, and the method is suitable for the ship controllable-pitch propeller system and other fields needing high-precision feedback calibration.

Description

Technical Field

[0001] The present invention relates to the technical field of ship adjustable pitch propellers, and specifically to an adjustable pitch propeller pitch signaling module based on an MCU and a static calibration method. Background Art

[0002] The adjustable pitch propeller (APP) system is widely used in ships and aircraft. It can adjust the thrust by changing the angle of the propeller blades to achieve more efficient power transmission and control performance. In these systems, the pitch signal is a key technology for monitoring and controlling the propeller angle (pitch) of the ship. It is important to ensure that the feedback signal has sufficient accuracy and stability. However, these systems may have certain drift and errors during long-term use.

[0003] Therefore, the feedback calibration of the pitch signal of the controllable pitch propeller is a key link to ensure the accurate and reliable operation of the ship's controllable pitch propeller system. In the prior art, mechanical calibration methods and analog signal calibration methods are often used.

[0004] The mechanical calibration method is a traditional calibration method and is widely used in early adjustable pitch propeller systems. This method adjusts the mechanical components so that the system outputs corresponding signals at different pitch positions, thereby achieving the purpose of calibration. The specific scheme is: when the pitch is at -100%, 0%, and 100%, mechanical reference points are set respectively. These reference points are usually determined by mechanical limit switches or physical marks. The operator manually adjusts the adjustable pitch propeller to these reference points and records the corresponding signal output (such as voltage and current values). Subsequently, the length or position of the connecting rod is adjusted to ensure that the signal value at each reference point is consistent with the expected value. Repeated adjustments and tests are required until satisfactory accuracy is achieved. Although this method has a certain degree of simplicity and directness, it has obvious deficiencies in accuracy, stability and maintenance. The adjustment and calibration process is time-consuming and labor-intensive and requires frequent maintenance.

[0005] The analog signal calibration method uses a standard signal source (such as a precision voltage source or current source) to generate a known analog signal. For example, when the pitch position is -100%, 0%, and 100%, 4mA, 12mA, and 20mA current signals are generated respectively. The reference signal is then input into the system, and the output signal of the system at these reference points is measured. The system error is corrected by adjusting the gain and offset circuits inside the system, such as using a potentiometer for hardware adjustment to ensure that the error is within an acceptable range. The adjusted output is consistent with the reference signal.

[0006] Analog signal calibration is limited by the accuracy of the reference signal source. Any slight error in the reference signal source will affect the calibration result. Environmental changes such as temperature and humidity will also affect the stability of the analog signal, resulting in unstable calibration results. Precision signal sources and measuring equipment are required, and the operation is complicated and time-consuming. Repeated measurements and adjustments are required, which increases the workload and time cost. Hardware adjustment methods cannot respond to system changes in real time and there is a delay. Summary of the invention

[0007] In order to solve the problems existing in the background technology, the present invention provides a pitch control propeller pitch signaling module based on MCU, which includes an MCU control unit and a potentiometer sensor unit connected to the MCU control unit for communication, a setting and fine-tuning control unit, a signal output unit, a storage unit and an indication and display 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 buttons and DIP switch manual operation components, and is provided with setting mode and fine-tuning mode. The preliminary correspondence between the pitch position and the output value of the potentiometer is established through the setting mode operation; the pitch feedback signal is finely adjusted through the fine-tuning mode operation to make the output of the pitch transmission signal 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 pitch feedback currents in real time according to the control of the MCU; the communication interface sends communication traffic of the pitch feedback current or other calibration related information;

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

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

[0014] In the preferred solution, the MCU control unit is connected to the potentiometer sensor unit through a signal line, receives the voltage and current signals output by the potentiometer or receives the communication signal through the RS485 interface; the MCU control unit is connected to the buttons and dial switches of the setting and fine-tuning control unit through the GPIO interface, receives the operation instructions to enter the setting or fine-tuning mode, and reads the button input value to perform the calibration operation. The MCU control unit is connected to the signal output unit current output module through the control line to control it to output 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 to the indication and display unit through the GPIO interface or the I2C / SPI communication protocol to control the status of the LED indicator and the display content of the OLED screen.

[0015] In the preferred solution, the resistance type potentiometer provides a resistance value that varies 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; and the communication output type potentiometer outputs the communication volume 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 adjustable pitch propeller to the three reference positions of full reverse, zero pitch and full forward by pressing buttons, and triggers the setting operation; in the fine-tuning mode, the dial switch is used to switch to the fine-tuning mode, and the pitch feedback signal is fine-tuned by pressing buttons.

[0017] The static calibration method of the pitch signaling module of the adjustable pitch propeller based on MCU is carried out in the following steps:

[0018] S1. System preparation:

[0019] Ensure that the CPP system is in a calibrable state and that all components of the MCU-based CPP pitch transmitter module are correctly connected and functioning properly;

[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] The mechanical pitch of the adjustable pitch propeller is adjusted to three key reference points: full reverse, i.e. -100% pitch position, zero pitch, i.e. 0% pitch position, and full forward, i.e. +100% pitch position;

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

[0025] At each reference point, the output value of the potentiometer, i.e., resistance type, current output type, or communication output type, is read through the MCU;

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

[0027] S23: Storing reference point data

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

[0029] S24: Confirm that the setting is completed

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

[0031] S3, fine-tuning process:

[0032] S31: Enter fine-tuning mode

[0033] Switch to fine-tuning mode via the DIP switch and prepare to make fine adjustments to the pitch feedback signal;

[0034] S32: Select fine-tuning pitch position

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

[0036] S33: Perform fine-tuning operations

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

[0038] 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;

[0039] S34: Confirm fine-tuning results

[0040] After the fine-tuning is completed, check whether the fine-tuning result meets the requirements to ensure the accuracy and consistency between the output of the pitch signal and the actual pitch position;

[0041] S4, calibration completed:

[0042] Confirm that the setting and fine-tuning process has been successfully completed, close the calibration system, and prepare to put the CPP system into normal use;

[0043] S5. Monitoring and maintenance:

[0044] During normal system operation, the accuracy and stability of the pitch transmission signal are monitored regularly; if any abnormality or drift is found, the calibration process is initiated 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 operating normally, it detects whether the setting buttons at 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, thereby realizing the feedback signal setting function. The assigned value needs to be maintained after power off;

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

[0048] When the external input voltage is 0V, the car is in full reverse mode, and the MCU control unit collects the corresponding voltage offset.

[0049] When the external input voltage is 2.5V, that is, zero pitch, the MCU control unit collects the corresponding voltage offset;

[0050] When the external input voltage is 5V, the vehicle is completely normal, and the MCU control unit collects the corresponding voltage offset;

[0051] When the external input current is 4mA, the car is in full reverse mode, and the MCU control unit collects the corresponding current offset.

[0052] When the external input current is 12mA, that is, zero pitch, the MCU control unit collects the corresponding current offset;

[0053] When the external input reference current is 20mA, the vehicle is in good condition and the MCU control unit collects the corresponding current offset.

[0054] The beneficial effects achieved by the present invention 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, each unit is connected through a signal line or interface, thereby achieving efficient data transmission and control.

[0056] Second, the static calibration method based on MCU of the present invention realizes the high-precision correspondence between the pitch position and the transmission signal. Compared with the traditional mechanical calibration and analog signal calibration methods, this method can significantly improve the 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 the stored calibration data, thereby reducing the impact of environmental changes on the stability of the system. This calibration method divides the calibration process into two steps: setting and fine-tuning, which can be completed manually by pressing buttons and dial switches, without the need for complex precision equipment and repeated adjustments, greatly simplifying the operation process.

[0057] Third, the present invention adopts digital signal processing technology, and the MCU can process the input signal in real time and make corrections, 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 calibration. Compared with the hardware adjustment method, there is no delay problem. The method of the present invention is not only suitable for ship adjustable pitch propeller systems, but can also be extended to other fields that require high-precision feedback calibration. It has broad application prospects and potential market value. During the normal operation of the system, the accuracy and stability of the pitch transmission signal can be monitored regularly. Once an abnormality or drift is found, the calibration process can be started in real time for calibration, which improves the maintainability and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is the overall system structure diagram of the present invention;

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

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

[0061] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the various structures recorded in the following embodiments are merely illustrative, and the present invention is not limited to the various structures recorded in the following embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0062] Reference Figure 1-Figure 2The present invention provides a pitch signaling module for a pitch control propeller based on an MCU, which includes 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 that are communicatively connected to the MCU control unit, wherein:

[0063] 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;

[0064] The potentiometer sensor unit includes 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 includes buttons and DIP switch manual operation components, and is provided with setting mode and fine-tuning mode. The preliminary correspondence between the pitch position and the output value of the potentiometer is established through the setting mode operation; the pitch feedback signal is finely adjusted through the fine-tuning mode operation to make the output of the pitch transmission signal consistent with the actual pitch position;

[0066] 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 traffic of the pitch feedback current or other calibration related information;

[0067] The storage unit is located inside the MCU, including the on-chip Flash, which stores various data generated during the calibration process, including the pitch curve reference point, voltage or current offset;

[0068] The indication and display unit includes LED indicator lights and OLED screen display components to indicate different states and key information during the calibration process.

[0069] In the preferred solution, the MCU control unit is connected to the potentiometer sensor unit through a signal line, receives the voltage and current signals output by the potentiometer or receives the communication signal through the RS485 interface; the MCU control unit is connected to the buttons and dial switches of the setting and fine-tuning control unit through the GPIO interface, receives the operation instructions to enter the setting or fine-tuning mode, and reads the button input value to perform the calibration operation. The MCU control unit is connected to the signal output unit current output module through the control line to control it to output 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 to the indication and display unit through the GPIO interface or the I2C / SPI communication protocol to control the status of the LED indicator and the display content of the OLED screen.

[0070] In the preferred solution, the resistance type potentiometer provides a resistance value that varies 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; and the communication output type potentiometer outputs the communication volume 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 adjustable pitch propeller to the three reference positions of full reverse, zero pitch and full forward by pressing buttons, and triggers the setting operation; in the fine-tuning mode, the dial switch is used to switch to the fine-tuning mode, and the pitch feedback signal is fine-tuned by pressing buttons.

[0072] The static calibration method of the pitch signaling module of the adjustable pitch propeller based on MCU is carried out in the following steps:

[0073] S1. System preparation:

[0074] Ensure that the CPP system is in a calibrable state and that all components of the MCU-based CPP pitch transmitter module are correctly connected and functioning properly;

[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] The mechanical pitch of the adjustable pitch propeller is adjusted to three key reference points: full reverse, i.e. -100% pitch position, zero pitch, i.e. 0% pitch position, and full forward, i.e. +100% pitch position;

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

[0080] At each reference point, the output value of the potentiometer, i.e., resistance type, current output type, or communication output type, is read through the MCU;

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

[0082] S23: Storing reference point data

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

[0084] S24: Confirm that the setting is completed

[0085] Confirm that all benchmark data has been stored correctly and check to ensure there are no errors or anomalies;

[0086] S3, fine-tuning process:

[0087] S31: Enter fine-tuning mode

[0088] Switch to fine-tuning mode via the DIP switch and prepare to make fine adjustments to the pitch feedback signal;

[0089] S32: Select fine-tuning pitch position

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

[0091] S33: Perform fine-tuning operations

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

[0093] 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;

[0094] S34: Confirm fine-tuning results

[0095] After the fine-tuning is completed, check whether the fine-tuning result meets the requirements to ensure the accuracy and consistency between the output of the pitch signal and the actual pitch position;

[0096] S4, calibration completed:

[0097] Confirm that the setting and fine-tuning process has been successfully completed, close the calibration system, and prepare to put the CPP system into normal use;

[0098] S5. Monitoring and maintenance:

[0099] During normal system operation, the accuracy and stability of the pitch transmission signal are monitored regularly; if any abnormality or drift is found, the calibration process is initiated in real time for calibration.

[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 operating normally, it detects whether the setting buttons at 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, thereby realizing the feedback signal setting function. The assigned value needs to be maintained after power off;

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

[0103] When the external input voltage is 0V, the car is in full reverse mode, and the MCU control unit collects the corresponding voltage offset.

[0104] When the external input voltage is 2.5V, that is, zero pitch, the MCU control unit collects the corresponding voltage offset;

[0105] When the external input voltage is 5V, the vehicle is completely normal, and the MCU control unit collects the corresponding voltage offset;

[0106] When the external input current is 4mA, the car is in full reverse mode, and the MCU control unit collects the corresponding current offset.

[0107] When the external input current is 12mA, that is, zero pitch, the MCU control unit collects the corresponding current offset;

[0108] When the external input reference current is 20mA, the vehicle is in good condition and the MCU control unit collects the corresponding current offset.

[0109] Embodiment 1. This embodiment divides the static calibration process into two steps: setting and fine-tuning. During the setting process, the mechanical pitch is adjusted to three positions: full reverse, zero pitch, and full forward. The software reads the potentiometer output values ​​of these three positions. In any mode, the -100% initial value should not be between 0% and +100%, the +100% initial value should not be between -100% and 0%, and the 0% initial value should not be outside -100% and +100%. Two or more of the three values ​​cannot be the same. Finally, press the buttons on the MCU-based adjustable pitch propeller pitch transmission module to complete the setting of the pitch feedback signals at the three positions of +100%, 0%, and -100%.

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

[0111] The resistance range of the resistor potentiometer is 0-5KΩ. The MCU-based adjustable pitch propeller pitch signaling module provides it with a 0-5V (DC) power supply, and the voltage value of the collected resistor is used as the initial pitch feedback signal, which is read into the MCU-based adjustable pitch propeller pitch signaling module for subsequent adjustment.

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

[0113] The communication output potentiometer outputs the pitch feedback signal communication volume through RS485, and the MCU-based adjustable pitch propeller pitch signal transmission module reads the pitch feedback communication volume with the help of RS485 protocol.

[0114] After the MCU-based adjustable pitch propeller pitch transmission module software enters the pitch feedback signal setting function by cyclically scanning the DIP switch status, the pitch feedback signal output function is still operating normally. At the same time, the software detects whether there is any input to the setting buttons of the three pitch positions of +100%, 0%, and -100%. 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 assigned value needs to be maintained after power-off.

[0115] The MCU on-chip Flash stores the values ​​for deviation calibration based on external voltage and external current. The calibration value types include:

[0116] When the external reference voltage is 0V (full reverse), the MCU microcontroller collects the corresponding voltage offset; when the external reference voltage is 2.5V (zero pitch), the MCU microcontroller collects the corresponding voltage offset; when the external reference voltage is 5V (full forward), the MCU microcontroller collects the corresponding voltage offset; when the external reference current is 4mA (full reverse), the MCU microcontroller collects the corresponding current offset; when the external reference current is 12mA (zero pitch), the MCU microcontroller collects the corresponding current offset; when the external reference current is 20mA (full forward), the MCU microcontroller collects the corresponding current offset; the software sets 6 input status registers in Flash to store the above calibration data offsets respectively.

[0117] According to actual usage needs, the MCU-based adjustable pitch propeller pitch signal transmission module also needs to be designed with an output pitch feedback signal fine-tuning function, that is, switching to the pitch feedback signal fine-tuning mode through the dip switch, using the first button to switch the three fine-tuned pitch positions of +100%, 0%, and -100%, and then using the second and third buttons to add and subtract respectively to fine-tune the three reference points on the corresponding relationship curve between the output of the MCU-based adjustable pitch propeller pitch signal transmission module and the potentiometer output, thereby realizing the feedback current fine-tuning function.

[0118] The feedback current fine-tuning function program scans the dial switch. When the feedback current fine-tuning function is entered, the MCU-based adjustable pitch propeller pitch signaling module sets the IO corresponding register, collects the three button input values ​​in real time, and the OLED screen displays the current latest reference values ​​of full positive pitch, full negative pitch and pitch zero.

[0119] Finally, before the MCU-based adjustable pitch propeller pitch signaling module outputs the pitch feedback current, the main program reads the collected potentiometer voltage / current signal, and uses the input-output correspondence determined by the three points of full forward, full reverse, and pitch zero position to calculate the pitch feedback current output value corresponding to the current potentiometer voltage / current value. The MCU-based adjustable pitch propeller pitch signaling module CPU then controls the current output module to output two 4-20mA pitch feedback currents in real time. At the same time, the pitch feedback current is sent via RS485 communication.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The MCU-based controllable pitch propeller pitch signaling module is characterized by: It includes 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 which are communicatively connected to the MCU control unit, wherein: 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; The potentiometer sensor unit includes one or more of a resistance type potentiometer, a current output type potentiometer and a communication output type potentiometer; The setting and fine-tuning control unit includes buttons and DIP switch manual operation components, and is provided with setting mode and fine-tuning mode. The preliminary correspondence between the pitch position and the output value of the potentiometer is established through the setting mode operation; the pitch feedback signal is finely adjusted through the fine-tuning mode operation to make the output of the pitch transmission signal 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 traffic of the pitch feedback current or other calibration related information; The storage unit is located inside the MCU, including the on-chip Flash, which stores various data generated during the calibration process, including the pitch curve reference point, voltage or current offset; The indication and display unit includes LED indicator lights and OLED screen display components to indicate different states and key information during the calibration process.

2. The MCU-based controllable pitch propeller pitch signaling module according to claim 1, characterized in that: The MCU control unit is connected to the potentiometer sensor unit through a signal line, receives the voltage and current signals output by the potentiometer or receives the communication signal through the RS485 interface; the MCU control unit is connected to the buttons and the dial 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 to perform the calibration operation; the MCU control unit is connected to the current output module of the signal output unit through the control line, controls it to output two 4-20mA pitch feedback currents; at the same time, sends the pitch feedback current or other calibration related information 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 to 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.

3. The MCU-based controllable pitch propeller pitch signaling module according to claim 1, characterized in that: The resistance type potentiometer provides a resistance value that changes 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 volume of the pitch feedback signal through the RS485 interface.

4. The MCU-based controllable pitch propeller pitch signaling 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 propeller to the three reference positions of full reverse, zero pitch and full forward by pressing buttons, and triggers the setting operation; in the fine-tuning mode, switch to the fine-tuning mode through the dip switch, and fine-tune the pitch feedback signal by pressing buttons.

5. The static calibration method of the pitch signaling module of the controllable pitch propeller based on MCU according to any one of claims 1 to 4, characterized in that: Proceed as follows: S1. System preparation: Ensure that the CPP system is in a calibrable state and that all components of the MCU-based CPP pitch transmitter 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. Setting process: S21: Adjust the pitch position The mechanical pitch of the adjustable pitch propeller is adjusted to three key reference points: full reverse, i.e. -100% pitch position, zero pitch, i.e. 0% pitch position, and full forward, i.e. +100% pitch position; S22: Read the output value of the potentiometer At each reference point, the output value of the potentiometer, i.e., resistance type, current output type, or communication output type, is read through the MCU; For the resistance type potentiometer, the MCU reads its output voltage value; for the current output type potentiometer, the MCU directly reads the current value or converts it into a voltage value through a high-precision resistor; for the communication output type potentiometer, the MCU reads the communication volume through the RS485 interface; S23: Storing reference point data The read output value of the potentiometer is stored in the storage unit Flash of the MCU as the reference point data of the pitch curve; S24: Confirm that the setting is completed 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 via the DIP switch and prepare to make fine adjustments to the pitch feedback signal; S32: Select fine-tuning pitch position Select one or more of the pitch positions that need to be fine-tuned, i.e., +100%, 0%, and -100%, by using the buttons on the control unit; S33: Perform fine-tuning operations At the selected pitch position, fine-tune the pitch feedback signal through 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 fine-tuning results After the fine-tuning is completed, check whether the fine-tuning result meets the requirements to ensure the accuracy and consistency between the output of the pitch signal and the actual pitch position; S4, calibration completed: Confirm that the setting and fine-tuning process has been successfully completed, close the calibration system, and prepare to put the CPP system into normal use; S5. Monitoring and maintenance: During normal system operation, the accuracy and stability of the pitch signal are monitored regularly; if any anomaly or drift is found, the calibration process is initiated in real time for calibration.

6. The method according to claim 5, 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 state of the dial switch. While the pitch feedback signal output function is still operating normally, it detects whether the setting buttons at 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, thereby realizing the feedback signal setting function. The assigned value needs to be maintained after power off; The MCU on-chip Flash stores the values ​​for deviation calibration based on external voltage and external current. Six input status registers are set in the Flash to store the following calibration data offsets, including: When the external input voltage is 0V, the car is in full reverse mode, and the MCU control unit collects the corresponding voltage offset. When the external input voltage is 2.5V, that is, zero pitch, the MCU control unit collects the corresponding voltage offset; When the external input voltage is 5V, the vehicle is completely normal, and the MCU control unit collects the corresponding voltage offset; When the external input current is 4mA, the car is in full reverse mode, and the MCU control unit collects the corresponding current offset. When the external input current is 12mA, that is, zero pitch, the MCU control unit collects the corresponding current offset; When the external input reference current is 20mA, the vehicle is in good condition and the MCU control unit collects the corresponding current offset.

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