Dual-redundancy aircraft propeller wireless variable pitch system

Abstract

The utility model provides a dual-redundancy aircraft propeller wireless variable pitch system. The system comprises a driving integrated control board, a power supply distribution assembly box, a Lora communication system, a wireless data transmission radio station, a wireless power supply system, a transmitting double antenna, a receiving double antenna, a variable pitch motor and a propeller mechanical mechanism. Wherein the wireless power supply system comprises a transmitting coil group and a receiving coil group; the transmitting dual-antenna comprises an antenna I and an antenna II, and the receiving dual-antenna comprises an antenna III and an antenna IV; according to the system design provided by the utility model, an electric slip ring used in wired pitch change is replaced by a wireless pitch change mode, and wireless electric energy supply and wireless signal control of the pitch change motor are realized. And meanwhile, a dual-redundancy design of a Lora communication system and a wireless data transmission radio station is adopted to carry out wireless communication so as to control the variable-pitch motor.

Description

Technical Field

[0001] The utility model belongs to the technical field of wireless control of aviation flight, and in particular relates to a dual-redundant wireless pitch-changing system for aircraft propellers. Background Art

[0002] Research on variable-pitch propeller control systems aims to achieve a significant improvement in overall aircraft system efficiency compared to fixed-pitch propeller systems. Compared to fixed-pitch propeller systems, the use of variable propeller pitch improves propulsion system efficiency, significantly enhancing aircraft maneuverability, endurance, and overall system efficiency. Variable propeller pitch is achieved by generating a variable pitch drive force through the rotation of an electric motor, which drives a mechanical transmission mechanism to rotate the propeller blades, thereby changing the airflow's angle of attack on the blades and maintaining high propeller efficiency.

[0003] Typically, the pitch motor in a wired aircraft propeller pitch control system is contained within the propeller pitch mechanism and rotates at high speed. Electric propeller pitch control systems typically use conductive slip rings to connect the aircraft fuselage to the high-speed rotating propeller, providing power and transmitting signals to the pitch motor. Slip rings are required to control the high-speed rotating pitch motor. Compared to electrical slip rings for power and signal transmission, wireless power and signal transmission technology offers numerous advantages, including non-contact, wear-free operation, and flexibility. Wireless pitch control systems effectively avoid problems such as excessive surface temperatures of the slip rings, which can occur due to prolonged high-speed propeller rotation and lead to overheating of the slip rings and brushes. Furthermore, the complex electromagnetic field operating environment of aviation products, where large metal surfaces can hinder electromagnetic coupling, generate eddy current losses, and reduce transmission efficiency.

[0004] Therefore, in complex metal environments, it is very meaningful to reduce loss and increase coupling to achieve maximum efficiency transmission and improve wireless control stability. Utility Model Content

[0005] In view of this, an object of the present invention is to provide a dual-redundant aircraft propeller wireless pitch control system to improve the transmission efficiency of wireless communication control.

[0006] The technical solution of the utility model is: a dual-redundant aircraft propeller wireless pitch control system, comprising: a driving integrated control panel, a power distribution assembly box, a Lora communication system, a wireless data transmission radio, a wireless power supply system, a transmitting dual antenna, a receiving dual antenna, a pitch control motor, and a propeller mechanical mechanism; wherein the wireless power supply system includes a transmitting coil group and a receiving coil group; the transmitting dual antenna includes antenna 1 and antenna 2, and the receiving dual antenna includes antenna 3 and antenna 4;

[0007] Antenna 1 and antenna 3 are connected to the Lora communication system, and antenna 2 and antenna 4 are connected to the wireless data transmission radio;

[0008] The Lora communication system and the wireless data transmission radio are connected to the driving integrated control panel;

[0009] The Lora communication system and the wireless data transmission radio are connected to the pitch-variable motor for sending a rotation instruction to the pitch-variable motor; the pitch-variable motor drives the propeller mechanical mechanism to rotate;

[0010] The sensor in the variable pitch motor is used to monitor the actual rotation parameter information of the propeller mechanical mechanism. The variable pitch motor is connected to the Lora communication system and the wireless data transmission radio signal. The Lora communication system and the wireless data transmission radio feed back the received actual rotation parameter information of the propeller mechanical mechanism to the driving integrated control board;

[0011] The power distribution assembly box is connected to the transmitting coil group and the driving integrated control board respectively, and the receiving coil group is connected to the variable pitch motor.

[0012] Furthermore, the system also includes a display screen, and the driving integrated control panel is connected to the display screen; the power distribution assembly box is connected to the display screen.

[0013] Furthermore, the Lora communication chip model is E22-230T33E, the operating frequency is 233M, and it is used in conjunction with the transmitting antenna one and receiving antenna three of the fpc; the wireless data radio model is E95M-DTU-400SL22-485, the operating frequency is 433M, and it is used in conjunction with the transmitting antenna two and receiving antenna four of the ring.

[0014] Furthermore, a switching unit is provided in the assisted driving integrated control board, which is implemented by a single-chip microcomputer in conjunction with peripheral circuits. It communicates through the serial port, Lora communication and digital radio, and sends master and standby setting instructions to the Lora communication and digital radio according to the serial port communication status.

[0015] Furthermore, the 485 communication protocol is used between the brushless DC motor, the sensor and the driving integrated control board in the variable pitch motor.

[0016] Furthermore, the driving integrated control board selects an STM32 board as a controller, and its model is STM32F103ZET6.

[0017] This utility model provides a dual-redundant wireless aircraft propeller pitch control system. This system utilizes LoRa communication and a dual-redundant digital radio design to improve wireless communication control transmission efficiency. An STM32 board is used as the controller, and control signals are transmitted via dual antennas. The signals received by the dual antennas at the receiving end drive a motor for pitch adjustment. The system can also be integrated with a flight control system, leveraging sensors from the system to create an intelligent control system.

[0018] The dual-redundancy design of the aircraft propeller wireless pitch change system of the utility model enables more precise control of the pitch change angle of the pitch change system. At the same time, in order to solve the electromagnetic interference problem in wireless control, a dual-redundancy design communication control method is adopted to ensure a higher degree of safety and stability.

[0019] The system design proposed in this utility model replaces the slip rings used in wired pitch control with wireless pitch control, enabling wireless power supply and signal control for the pitch motor. To mitigate the impact of electromagnetic eddy current interference caused by complex electromagnetic devices on wireless signal transmission, a dual-redundancy design using a LoRa communication system and wireless data transmission radio is employed for wireless communication to control the pitch motor. The pitch motor provides power for the propeller's mechanical pitch mechanism to adjust the blade angle, thereby varying the propeller's flight torque. Information from the motor and sensors is fed back via a display screen to accurately display parameters such as the propeller pitch system's operating status, speed, and pitch. Based on this feedback from the motor and sensors, the integrated control panel precisely adjusts the output control signal, thereby reducing propeller pitch error and improving flight performance. This pitch system is suitable for drones and small and medium-sized aircraft with propellers, and can flexibly switch between multiple operating modes. This further enhances market competitiveness and generates significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present invention, and together with the description, serve to explain the principles of the present invention.

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0022] Figure 1 This is a schematic structural diagram of a dual-redundant aircraft propeller wireless pitch control system provided by the present invention;

[0023] Figure 2 This is a control analysis diagram of the dual-redundancy design of the aircraft propeller wireless pitch change system provided by the utility model;

[0024] Figure 3 An analysis diagram of the dual redundant communication system provided by the utility model;

[0025] Figure 4 This is the RS485 communication principle diagram provided by the utility model. DETAILED DESCRIPTION

[0026] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of systems consistent with certain aspects of the present invention, as detailed in the appended claims.

[0027] In the prior art, aircraft propeller electric pitch control systems typically use conductive slip rings to connect the aircraft fuselage and the high-speed rotating propeller to provide power and transmit signals to the pitch motor. However, due to the long-term high-speed rotation of the propeller, the surface temperature of the conductive slip ring may be too high. Therefore, this embodiment first provides a dual-redundant aircraft propeller wireless pitch control system, including: a driving integrated control panel 1, a power distribution assembly box 2, a Lora communication system 3, a wireless data transmission radio 4, a wireless power supply system, a transmitting dual antenna 7, a receiving dual antenna 9, a pitch motor 10, and a propeller mechanical mechanism 11; wherein the wireless power supply system includes a transmitting coil group 6 and a receiving coil group 8; the transmitting dual antenna 7 includes antenna 1 and antenna 2, and the receiving dual antenna 9 includes antenna 3 and antenna 4;

[0028] Antenna 1 and antenna 3 are connected to Lora communication system 3, and antenna 2 and antenna 4 are connected to wireless data transmission station 4;

[0029] The Lora communication system 3 and the wireless data transmission radio 4 are connected to the driving integrated control panel 1;

[0030] The Lora communication system 3 and the wireless data transmission radio 4 are connected to the variable pitch motor 10 for sending a rotation instruction to the variable pitch motor 10; the variable pitch motor 10 drives the propeller mechanical mechanism 11 to rotate;

[0031] The sensor in the variable pitch motor is used to monitor the actual rotation parameter information of the propeller mechanical mechanism 11. The variable pitch motor is connected to the Lora communication system 3 and the wireless data transmission radio 4. The Lora communication system 3 and the wireless data transmission radio 4 feed back the received actual rotation parameter information of the propeller mechanical mechanism 11 to the driving integrated control board 1;

[0032] The power distribution assembly box 2 is connected to the wireless power supply system and the driving integrated control board 1 respectively, and the receiving coil group 8 in the wireless power supply system is connected to the brushless DC motor.

[0033] It also includes a display screen 5 , and the driving integrated control panel 1 is connected to the display screen 5 ; the power distribution assembly box 2 is connected to the display screen 5 .

[0034] The wireless power supply system in this embodiment is of magnetic induction type. The direct current input by the wireless power supply transmitter is converted into alternating current through a rectifier and inverter circuit. Then, according to the system's output frequency requirements, it is processed by a high-frequency inverter circuit to become a corresponding high-frequency alternating current, which excites the coupling coil and the compensation structure to produce resonance. One side of the coil generates a high-frequency alternating magnetic field, which transmits power to the other side of the coil through magnetic coupling and generates high-frequency alternating current again. Finally, after relevant rectification and filtering, the direct current is delivered to the power load.

[0035] The power distribution assembly box 2 has multiple power distribution circuits and is connected to the transmitting coil assembly 6, which contains a high-frequency oscillator, power amplifier, and other transmitting devices. The power distribution assembly box 2 is also connected to the driving integrated control panel 1 and the display screen 5.

[0036] Specifically, the power distribution assembly box is equipped with multiple voltage supplies. It is connected to the coupling coil and contains a conversion and adjustable circuit. The power supply can provide an adjustable voltage output from 12V to 48V. The power distribution assembly box is connected to the wireless power transmission coupling coil. It is also connected to the driving integrated control board to provide 5V and 3.3V power supplies, and to the display screen to provide 5V power.

[0037] This implementation scheme uses a switching unit to monitor / switch the working status of two sets of transmitting antennas and two sets of receiving antennas; the switching unit is implemented by a single-chip microcomputer in conjunction with peripheral circuits, and communicates with Lora communication and digital radio through the serial port, and sends master and standby setting instructions to Lora communication and digital radio according to the serial port communication status; the single-chip microcomputer I / O port controls the power-on contactor of the driving unit through an intermediate relay; when Lora communication works as the host, if the Lora communication system detects a fault or the communication with the switching unit is interrupted, the switching unit cuts off the drive of the Lora communication and sends a master-slave switching instruction to the digital radio system, and the digital radio immediately starts working as the host.

[0038] To ensure accurate transmission of pitch control commands, antennas 1 and 2 utilize a dual-redundant system. Antennas 3 and 4 within the dual receiving antennas 9 are connected to the signal input of the pitch motor 10. The receiving coil assembly 8 is connected to the power input of the pitch motor 10. The rotational output of the pitch motor 10 drives the propeller pitch mechanism 11, adjusting the propeller blade angle. Sensors monitor the actual rotational status of the pitch system, including speed and pitch data, and these parameters are fed back to the pilot integrated control board 1 via the dual-redundant communication system.

[0039] The LoRa communication chip is E22-230T33E, operating at 233 MHz. Antennas 1 and 3 are FPC antennas. The wireless data radio is E95M-DTU-400SL22-485, operating at 433 MHz. Antennas 2 and 4 are circular ring antennas. Since they operate at different frequencies, they won't be affected by interference.

[0040] Applying the above system, the following control process is adopted:

[0041] S1: After coupling occurs through the high-frequency oscillator and power amplifier in the transmitting coil assembly circuit, the receiving coil assembly rectifies, extracts, amplifies, and processes the resulting electrical energy. The receiving coil assembly's power output is connected to the variable-pitch motor, providing wireless power to the motor.

[0042] S2: The LoRa communication system and wireless data transmission radio are connected to the driving integrated control board, which is an STM32F103ZET6. The driving integrated control board simultaneously sends and receives signal instructions to the LoRa communication system and the wireless data transmission radio. The LoRa communication system and the wireless data transmission radio are data synchronized.

[0043] S3: Antennas 1 and 2 in the transmitting coil assembly and dual antenna assembly are connected to the LoRa communication system, while Antenna 2 is connected to the wireless data transmission station. To ensure accurate transmission of variable-range control commands, Antennas 1 and 2 utilize a dual-redundant design. Antennas 3 and 4 in the receiving coil assembly and dual antenna assembly function as dual antennas to receive variable-range control commands, preventing signal transmission obstruction caused by electromagnetic eddy current interference caused by the complex environment of electromagnetic devices.

[0044] S4: The pitch motor receives the pitch command from the antenna and drives the propeller mechanical transmission mechanism to change the propeller blade angle.

[0045] S5: Sensors monitor the actual working status, speed, pitch data and other information parameters of the variable pitch system, which are then fed back to the driving integrated control board by the dual redundant communication system and displayed on the display screen.

[0046] The composition of the dual redundant communication system is as follows: Figure 3 As shown in the figure, the LoRa communication system and data radio are the core control system. The LoRa communication system's SMA antenna interface is connected to the IPXE interface of antenna one. The data radio's antenna interface is connected to the antenna interface of antenna two. The LoRa communication system and data radio transmit rotation commands to antennas three and four, which then receive these commands. The logic circuit control components in the variable pitch motor drive the MS4005v3 series brushless DC motor, which in turn drives the propeller mechanical structure through a speed reducer. The variable pitch motor's integrated circuit includes a limit switch that stops the motor if a limit switch is encountered.

[0047] The variable pitch motor integrates a brushless DC motor, an angle sensor, and a limit switch. The brushless DC motor is the driving component, while the angle sensor and limit switch are the measuring components. All three are integrated into the variable pitch motor. The LoRa communication, data radio, and antenna contain numerous electronic components, making electromagnetic interference failures much more likely than the motor, limit switch, and sensor. Therefore, the dual-redundant communication system primarily addresses the coordination of the LoRa communication, antenna 1, data radio, antenna 2, and the dual antennas 3 and 4.

[0048] In a dual-redundant communication system, the switching unit monitors and switches the operating status of the two transmitting and receiving antennas. Implemented by a highly reliable single-chip microcontroller (MCU) with sophisticated peripheral circuitry, the switching unit communicates with the LoRa communication system and digital radio via a serial port, sending master / slave configuration commands to the system and radio based on the serial communication status. The MCU's I / O port controls the driver unit's power-on contactor via an intermediate relay. When the LoRa communication system is operating as the master, if it detects a fault or communication with the switching unit is interrupted, the switching unit disconnects the driver and sends a master / slave switch command to the digital radio. The radio immediately begins operating as the master, ensuring uninterrupted communication.

[0049] Specifically, the wireless data transmission radio 4 is internally provided with an antenna interface, an indicator light, a reset button (embedded), a power interface, a motor control signal input port, and a data communication serial port; the Lora communication system 3 is provided with a data communication serial port, a motor control signal input port, an antenna interface, and a status indicator light.

[0050] Specifically, the driving integrated control board 1 is provided with interfaces such as a controller connection power supply port, a motor control signal output port, a propeller speed signal input port, a data communication serial port, an intelligent voice broadcast, and a buzzer alarm; the display screen 5 is 4.7 inches in size, on which the operating status of each major component can be seen, and a manual adjustment operating mode option is provided on the display screen; the DC brushless motor and sensor in the variable pitch motor 10 and the driving integrated control board 1 all use the 485 communication protocol.

[0051] In the RS485 communication network, a 485 transceiver is usually used to convert TTL levels into RS485 differential signals. The serial port TxD of the autonomous driving integrated control board sends data, which is converted into a differential signal by the 485 transceiver and transmitted to the bus. When receiving data, the 485 transceiver converts the differential signal on the bus into a TTL signal and transmits it from RxD to the serial port of the autonomous driving integrated control board. Figure 4 U16 is a 3.3V low-power half-duplex transceiver, powered by 3.3V and meeting RS-485 and RS-422 standards. The RX (PA3) and TX (PA2) pins of the USART controller chip are connected to the RO and DI pins of U16, respectively. The A and B pins of U16 are connected to the terminal block.

[0052] At the receiver output, if AB ≥ -0.05V, RO is high. When AB ≤ -0.2V, RO is low; if A and B are floating or shorted, RO is also high. U16's pin 2, RE, is the receive enable. The overline indicates active low, meaning that when pin 2 is low, U16 receives data. U16's pin 3, DE, is the output enable. Active high, meaning that when pin 3 is high, U16 transmits data. R10 is the termination resistor, with a value of 120Ω.

[0053] In summary, the present invention adopts a dual-redundancy design, connecting the Lora communication system and the wireless data transmission radio to the variable pitch motor via the driving integrated control panel. The variable pitch system uses wireless power supply technology and wireless signal transmission technology to control the variable pitch motor during high-speed rotation. The DC brushless motor is used to provide variable pitch power for the propeller pitch mechanism. The display screen displays feedback from the sensors in the variable pitch motor, reflecting the actual rotational working status, speed, pitch data, and other information parameters of the propeller pitch system. The precise pitch value is calculated by combining the set propeller characteristic parameters, allowing the pitch, airspeed, and engine power output of the variable pitch propeller to be precisely matched.

[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These changes and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A dual-redundant aircraft propeller wireless pitch control system, characterized in that: include: Driving integrated control panel (1), power distribution assembly box (2), Lora communication system (3), wireless data transmission radio (4), wireless power supply system, transmitting dual antenna (7), receiving dual antenna (9), pitch-changing motor (10), propeller mechanical mechanism (11); wherein the wireless power supply system includes a transmitting coil group (6) and a receiving coil group (8); the transmitting dual antenna (7) includes antenna 1 and antenna 2, and the receiving dual antenna (9) includes antenna 3 and antenna 4; the pitch-changing motor is an integrated structure, including a DC brushless motor, an angle sensor and a limit switch; Antenna 1 and antenna 3 are connected to the Lora communication system (3), and antenna 2 and antenna 4 are connected to the wireless data transmission station (4); The Lora communication system (3) and the wireless data transmission radio (4) are connected to the driving integrated control panel (1); The Lora communication system (3) and the wireless data transmission radio (4) are connected to the pitch-variable motor (10) and are used to send a rotation instruction to the pitch-variable motor (10); the pitch-variable motor (10) drives the propeller mechanical mechanism (11) to rotate; The angle sensor in the pitch-changing motor (10) is used to monitor actual rotation parameter information of the propeller mechanical mechanism (11). The pitch-changing motor (10) is connected to the Lora communication system (3) and the wireless data transmission radio (4) for signal transmission. The Lora communication system (3) and the wireless data transmission radio (4) feed back the received actual rotation parameter information of the propeller mechanical mechanism (11) to the driving integrated control board (1). The power distribution assembly box (2) is respectively connected to the transmitting coil group (6) and the driving integrated control panel (1), and the receiving coil group (8) is connected to the variable pitch motor (10).

2. A dual-redundant aircraft propeller wireless pitch control system according to claim 1, characterized in that: It comprises a display screen (5), wherein the driving integrated control panel (1) is connected to the display screen (5); and the power distribution assembly box (2) is connected to the display screen (5).

3. The dual-redundant aircraft propeller wireless pitch control system according to claim 1, characterized in that: The Lora communication chip model is E22-230T33E, the operating frequency is 233M, and it is used in conjunction with the transmitting antenna one and receiving antenna three of the fpc; the wireless data radio model is E95M-DTU-400SL22-485, the operating frequency is 433M, and it is used in conjunction with the transmitting antenna two and receiving antenna four of the ring.

4. The dual-redundant aircraft propeller wireless pitch control system according to claim 1, characterized in that: The driving integrated control panel (1) is provided with a switching unit, which is implemented by a single chip microcomputer in conjunction with a peripheral circuit, and communicates with the Lora communication and data transmission radio via a serial port, and sends a master / slave setting instruction to the Lora communication and data transmission radio according to the serial port communication status.

5. The dual-redundant aircraft propeller wireless pitch control system according to claim 1, characterized in that: The 485 communication protocol is used between the DC brushless motor, the sensor and the driving integrated control board (1) in the variable pitch motor (10).

6. The dual-redundant aircraft propeller wireless pitch control system according to claim 1, characterized in that: The driving integrated control board (1) selects an STM32 board as a controller, and its model is STM32F103ZET6.

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