Modularized multi-rotor unmanned aerial vehicle flight control development teaching platform and method

Abstract

The invention belongs to the technical field of multi-rotor unmanned aerial vehicle control system design and development teaching equipment, and discloses a modularized multi-rotor unmanned aerial vehicle flight control development teaching platform and method. The platform comprises a hardware system, a flight control hardware system is disassembled into independent sub-modules, the independent flight control sub-modules are connected through a standardized signal connection interface and a pluggable interface to form a complete flight control hardware system, and unmanned aerial vehicle flight control system design is carried out. The method is used for visually contacting a flight control core assembly and clearing a flight control bottom layer circuit and signal transmission logic. According to the invention, the innovative development threshold is reduced: the pluggable sub-modules are in wired connection through a standardized interface, so that students can intuitively master hardware system composition and data transmission, the software adopts a modular architecture, and a driving function library written based on a standard library idea is provided, so that the students can conveniently apply a core algorithm to realize a corresponding control algorithm and application; and meanwhile, a common hardware driving library is expanded, so that function expansion is facilitated.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of multi-rotor unmanned aerial vehicle control system design and development teaching equipment, and particularly relates to a modular multi-rotor unmanned aerial vehicle flight control development teaching platform and method. BACKGROUND

[0002] With the large-scale landing application of unmanned aerial vehicle technology in the fields of industry, agriculture, security and the like, the unmanned aerial vehicle related majors (such as unmanned aerial vehicle system engineering, low-altitude technology and engineering, unmanned aerial vehicle application technology and the like) have experienced explosive growth. The flight control related equipment used in the current teaching scene has significant shortcomings and is difficult to match the core requirements of professional teaching.

[0003] Commercial unmanned aerial vehicle products mostly adopt integrated packaging design, and the core flight control system is highly integrated in a sealed module to form a typical black box structure. Students cannot access internal core components such as sensors, processors and drive units, and can only master basic flight functions through finished products, which makes it difficult to deeply understand the underlying logic and principles of flight control, directly leading to a serious disconnection between industry leading technology and college teaching.

[0004] There are two outstanding problems in the existing special unmanned aerial vehicle teaching equipment: one is a secondary development system based on an open source flight control, for example, most secondary development products based on Pixhawk. Since the Pixhawk flight control needs to consider multiple models, the function design is comprehensive but has high redundancy, and the underlying code and hardware architecture are too complex for beginners and classroom teaching scenarios, which is not conducive to teaching landing. The other type of equipment has a single function and can only complete basic theory demonstration, which belongs to a principle verification type tool and cannot support students to practice the whole process from hardware construction to software development, greatly limiting the space for students to independently design and innovate.

[0005] Through the above analysis, the existing problems and defects in the prior art are that the existing unmanned aerial vehicle professional teaching does not provide a modular, open and highly adaptive multi-rotor unmanned aerial vehicle flight control teaching platform for teaching scenarios, and cannot solve the problems of shortage of teaching resources, insufficient equipment adaptability and poor practical teaching effect. SUMMARY

[0006] To overcome the problems in the related art, the present application discloses a modular multi-rotor unmanned aerial vehicle flight control development teaching platform and method, and particularly relates to an open flight control assembly and development platform based on an stm32 embedded chip.

[0007] The technical solution is as follows: the modular multi-rotor unmanned aerial vehicle flight control development teaching platform comprises:

[0008] The hardware system is disassembled into independent sub-modules, connected through a standardized signal connection interface and a pluggable interface to form a complete hardware system of the flight control, and used for designing the flight control system of the unmanned aerial vehicle, intuitively contacting the core components of the flight control, clarifying the bottom line of the flight control and the signal transmission logic, measuring the running signals of the unmanned aerial vehicle through the test points reserved in the sub-modules, and completing the fault detection of the flight control.

[0009] The software system adopts a modular software layered architecture to design and develop the software of the multi-rotor unmanned aerial vehicle in stages.

[0010] The teaching system is used for the progressive design of experimental projects from the hardware driving layer to the data processing layer to the application layer, and the code from the bottom layer to the upper layer, and the theoretical difficulty is gradually increased.

[0011] The hardware system comprises:

[0012] The core control module is connected with the debugging module, the sensor module, the flight control output PWM module and the communication module through the reserved I2C, SPI and UART peripheral interfaces, and is used for issuing the multi-rotor unmanned aerial vehicle running state control instructions to the above modules.

[0013] The debugging module integrates the OLED module and the wireless serial port module, and is used for monitoring the running state of the core control module, the sensor module, the flight control output PWM module and the communication module in real time.

[0014] The sensor module integrates the attitude sensor and the air pressure sensor, communicates with the core control module through the I2C / SPI interface, and measures the original signals of the attitude sensor and the air pressure sensor through the data test points.

[0015] The communication module comprises an SBUS receiver, realizes the remote controller instruction receiving, and completes the data transmission between the core control module and the ground station through the wireless serial port unit.

[0016] The flight control output PWM module is used for driving the multi-rotor unmanned aerial vehicle.

[0017] The hardware system further comprises:

[0018] The power module is configured with a power protection module and a main power supply interface, adopts a physical key plus color coding standardized wiring terminal, and supplies power to the above modules.

[0019] The hardware system further comprises an expansion module which is connected with the optical flow sensor, the ultrasonic sensor, the GPS / Beidou positioning sensor and the communication expansion module peripheral through the I2C, SPI and UART universal interfaces reserved in the core control module, and provides expansion content for different function experiments of the multi-rotor unmanned aerial vehicle.

[0020] The OLED module comprises an on-board OLED debugging window.

[0021] The software system comprises:

[0022] A hardware driver layer for providing standardized drivers of various hardware systems;

[0023] A data processing and control algorithm layer for realizing core data processing and control functions;

[0024] An application layer for realizing task management and data display in cooperation with a ground station.

[0025] The hardware driver layer is integrated with OLED display driver, attitude sensor data reading driver, remote control data reading driver, motor PWM control driver and wireless serial communication driver, and is provided with a supporting driver development document containing function and parameter description;

[0026] The data processing and control algorithm layer comprises a sensor data processing and solving module integrated with Kalman filter algorithm for noise suppression of original data of attitude sensors and air pressure sensors, a complementary fusion algorithm for fusion processing of accelerometer and gyroscope data, and a calibration program of attitude sensors and air pressure sensors;

[0027] A PID controller for providing attitude PID control algorithm of attitude angular velocity and angle, position loop PID control algorithm based on optical flow sensor and air pressure sensor, reserving a quick parameter adjustment interface and supporting real-time modification of PID parameters through a ground station;

[0028] A power solving module for converting control instructions of power distribution and redundancy control into PWM duty cycles of 4 or 6 motors;

[0029] The application layer comprises:

[0030] A flight data transmission and real-time display module for being responsible for encapsulation and transmission of different ground station protocols of flight data and for data storage;

[0031] A flight mode and automatic flight task management module for realizing flight mode switching and automatic task execution of constant height, constant point and straight line motion.

[0032] Another object of the present application is to provide a testing method of the modular multi-rotor unmanned aerial vehicle flight control teaching platform, which is implemented in the modular multi-rotor unmanned aerial vehicle flight control teaching platform, and comprises the following steps:

[0033] S1, preparing hardware systems and software systems;

[0034] S2, based on the prepared hardware system, software system, each module, multi-rotor unmanned aerial vehicle flight control phased control;

[0035] S3, through the above phased implementation, complete from hardware system building, software system software programming writing to test the whole process.

[0036] In step S2, the multi-rotor unmanned aerial vehicle flight control is divided into stages, including:

[0037] Stage 1, STM32-based control system development and debugging platform building;

[0038] Stage 2, unmanned aerial vehicle attitude sensor data acquisition and processing;

[0039] Stage 3, unmanned aerial vehicle communication system development;

[0040] Stage 4, unmanned aerial vehicle power drive system development;

[0041] Stage 5, unmanned aerial vehicle control algorithm design and development;

[0042] Stage 6, overall test of unmanned aerial vehicle control system.

[0043] Stage 1, STM32-based control system development and debugging platform building, including:

[0044] Step 1, hardware system building, using physical key position and color coding terminal, connecting the core control module with the OLED module of the debugging module, wireless serial port module, power supply end 5V power supply, communication module I2C / SPI interface, and installing attitude sensor, air pressure sensor, SBUS receiver, sensor module, flight control output PWM module, expansion module, complete hardware system circuit building;

[0045] Step 2, software system building, through calling IIC serial port driver and UART serial port driver of bottom layer driver, writing OLED driver program and serial port debugging driver of bottom layer driver, configuring project environment in Keil MDK, compiling and downloading basic program, realizing OLED display variable name and data, ground station can be connected with MCU serial port, can send and receive data;

[0046] Step 3, function verification, through the on-board OLED debugging window of the OLED module to view the displayed data name and value, the ground station can be connected with serial port and display the data;

[0047] Stage 2, unmanned aerial vehicle attitude sensor data acquisition and processing, including:

[0048] Step a, sensor data acquisition, MPU6050 attitude sensor, MS5611 barometric pressure sensor through I2C interface access to the core control module, through the call IIC serial driver, write attitude sensor data acquisition function, realize the original data acquisition through OLED and ground station detection output original angular velocity, acceleration, can be combined with improved algorithm or improved calculation formula to describe the implementation content;

[0049] Step b, attitude solution and filtering, write Kalman filter function and complementary fusion function, noise suppression to the original data, realize the attitude solution, through the improved algorithm or improved technical formula describes the specific implementation process, for example, Kalman filter function and complementary fusion function can be improved formula;

[0050] Phase 3 unmanned aerial vehicle communication system development includes:

[0051] Step (1), remote controller SBUS signal receiving and analysis, SBUS communication module access to the core control module UART interface, call UART driver, write remote receiver data and SBUS analysis function, analysis for throttle, pitch, roll, heading command;

[0052] Step, flight control and ground station data communication test, modify the NRF24L01 communication unit code, through data encapsulation, realize the flight parameter of core control module and ground station display driver data transmission, verify the communication stability within 50 meters;

[0053] Phase 4 unmanned aerial vehicle power drive system development includes:

[0054] Step (i), motor drive system development, PWM drive module access to the core control module, call the bottom layer of PWM timer driver, write motor drive code, drive the rotor motor rotation, use oscilloscope to measure PWM signal duty cycle;

[0055] Step (ii), power solution module development, write data processing and control algorithm layer of power solution program, convert attitude command to 4, 6 way motor PWM duty cycle, realize the mapping of instruction and power, verify the linear correspondence between motor speed and instruction;

[0056] Phase 5 unmanned aerial vehicle control algorithm design and development includes:

[0057] Step (I), angular velocity loop PID design, write PID controller, debug angular velocity loop PID parameters, write program to realize sensor data, angular velocity control, motor output closed loop logic, through the ground station real-time modification parameters, test angular velocity response time ≤100ms;

[0058] Step (II), angle ring PID design, superimposed angle ring PID control, build double ring PID control logic, test unmanned aerial vehicle attitude control precision, record control effect under different parameters;

[0059] Phase 6 unmanned aerial vehicle control system overall test includes:

[0060] Step one, PID parameter adjustment, the user adjusts the angle velocity ring, angle ring PID parameter through the parameter adjustment interface reserved by the ground station, completes the hovering test of the four-rotor unmanned aerial vehicle;

[0061] Step two, data analysis, the remote control expected attitude data and the actual control attitude angle detected by the attitude sensor are sent to the ground station data display and analysis page, the change curve is drawn by the curve drawing plug-in, the attitude control performance is analyzed in real time, the ground station data storage function is started, the flight data is exported, the stability of the attitude and height data is analyzed, and the experiment is completed.

[0062] In combination with all the technical solutions described above, the beneficial effects possessed by the present application are that the present application creates a modular and transparent teaching carrier, and solves the black box dilemma of commercial unmanned aerial vehicles. The core components of the flight control system are designed in a split manner, the internal components of the control system are integrated into a plug-in sub-module, the precise connection between the modules is realized through Dupont wire, students can directly observe the hardware structure, underlying signal transmission and power supply line connection principle, the problem of disconnection between industry technology and teaching is solved from the root, and the core gap of unmanned aerial vehicle professional teaching resources is effectively filled.

[0063] The present application constructs a full-process practice link and strengthens the core ability training of application-oriented talents. A complete practice system of hardware building-software programming-system debugging-flight test is built to support students to carry out independent design and innovative development, completely replace traditional principle verification type equipment, accurately meet the core needs of engineering practice ability and problem solving ability in application-oriented talent training, and finally realize the closed-loop teaching goal of teaching, learning and doing.

[0064] The modular multi-rotor unmanned aerial vehicle flight control teaching platform of the present application has the following remarkable beneficial effects compared with the prior art:

[0065] (1) Teaching adaptability: accurately solve professional teaching problems; break through the barriers between theory and practice: through modular transparent design, break the black box limitation of commercial unmanned aerial vehicle, let students directly contact the core components and underlying principles of flight control system, solve the problem of disconnection between industry technology and teaching, fill the gap of unmanned aerial vehicle professional teaching resources. Reduce the risk of teaching equipment loss: innovative use of physical key position and color coding error proof interface and power protection circuit, avoid wiring errors from the structure, at the same time, through the self-resetting fuse and TVS diode, realize the automatic protection of overcurrent and overvoltage, the equipment failure rate is reduced to ≤5%, which greatly reduces the maintenance cost of teaching equipment. Adapt to project-based teaching whole process: supporting 48 hours of course design (corresponding to table 1 project), realize the teaching closed loop of hardware building-software programming-system debugging-flight test, meet the needs of new engineering project-based teaching.

[0066] (2) Ability training: strengthen students' comprehensive practice and innovation ability; improve engineering practice ability: the platform supports students to complete the whole process operation such as wiring, programming and debugging independently, measures signals and troubleshoots faults through multimeter, oscilloscope and other tools, effectively improves students' hardware operation, software development and problem solving ability. Support multi-disciplinary knowledge integration application: organically integrate embedded development, automatic control, sensor technology, communication technology and other multi-disciplinary knowledge points, let students connect scattered course content in practice, cultivate system thinking and cross-disciplinary integration ability. Reduce the threshold of innovation and development: the software adopts modular architecture and high coverage rate annotation (≥80%), students can directly call driver function and modify PID parameter, without modifying the core logic to realize function extension (such as adding autonomous obstacle avoidance module), stimulate innovation potential, adapt to the needs of discipline competition and scientific research exploration.

[0067] (3) Application and promotion: consider economic efficiency and large-scale application; high scalability and compatibility: hardware selects general STM32F407 chip, MPU6050 and other standardized components, reserves multiple types of peripheral interface, supports the expansion of GPS, computer vision and other modules; software is developed based on STM32 standard library, compatible with Keil, IAR and other mainstream development environments, can adapt to the teaching needs of different majors (such as electronic information engineering, automation, unmanned aerial vehicle application technology). Easy to scale up: modular assembly and wiring operation is simple, complete teaching resource package is provided, which can be quickly configured in batches in university laboratory. BRIEF DESCRIPTION OF DRAWINGS

[0068] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the principles of the present disclosure;

[0069] Figure 1 is a schematic diagram of the hardware system of the modular multi-rotor unmanned aerial vehicle flight control development teaching platform provided by the embodiment of the present application;

[0070] Figure 2 is a posture sensor installation schematic diagram provided by the embodiment of the present application;

[0071] Figure 3 is an OLED module installation schematic diagram provided by the embodiment of the present application;

[0072] Figure 4 is an SBUS receiver installation schematic diagram provided by the embodiment of the present application;

[0073] Figure 5 is an air pressure sensor installation schematic diagram provided by the embodiment of the present application;

[0074] Figure 6 is a software system schematic diagram of a modular multi-rotor unmanned aerial vehicle flight control development teaching platform provided by the embodiment of the present application;

[0075] Figure 7 is a control method flow chart of a modular multi-rotor unmanned aerial vehicle flight control development teaching platform provided by the embodiment of the present application;

[0076] In the figure: 1, core control module; 2, OLED module; 3, wireless serial port module; 4, attitude sensor; 5, air pressure sensor; 6, SBUS receiver; 7, power module; 8, bottom drive layer; 9, data processing and control algorithm layer; 10, application layer. DETAILED DESCRIPTION

[0077] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below. In the following description, a lot of specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the scope of the present application, so the present application is not limited to the specific implementation disclosed below.

[0078] In view of the pain points of existing unmanned aerial vehicle flight control teaching equipment product flight control black box, open source system complex function, and single function of special equipment, the present application provides a modular multi-rotor unmanned aerial vehicle flight control development test platform. The platform adopts hardware modularization splitting and software layered architecture design, takes STM32F407 chip as the core, splits independent pluggable modules such as core control, sensor and communication, and connects through standardized interfaces; the software is based on STM32 standard library to build a three-layer architecture, and each layer is independently encapsulated. The platform can enable students to intuitively master the flight control bottom layer principle, complete the whole process practice from hardware construction to flight test, reduce the innovation threshold and equipment loss, consider the integration of multidisciplinary knowledge, adapt to the project teaching needs of colleges and universities, and is economical, good in expansibility, and convenient for large-scale popularization and application.

[0079] The application provides a modular multi-rotor unmanned aerial vehicle flight control development teaching platform, which comprises a developed hardware module and a software architecture, and is completed by students according to a teaching guidebook.

[0080] A hardware system, which connects the students by means of a standardized interface and a pluggable base, so that the students can intuitively view the hardware system and the connection.

[0081] A software system, which is completed by the students trained according to an experimental guidebook in layers.

[0082] A teaching system, which mainly combines and experiments the modules.

[0083] In the embodiment, the modular multi-rotor unmanned aerial vehicle flight control development teaching platform adopts an overall design of hardware modularization and software layered architecture.

[0084] As shown in Figures 1-5 , the hardware system is modularized.

[0085] The modular multi-rotor unmanned aerial vehicle flight control development teaching platform takes an STM32F407 series chip as a core, constructs independent functional modules such as a core control module 1, a debugging module, a sensor module, a communication module and a driving module, and connects the modules through a standardized interface. Figure 1

[0086] The core control module 1 (MCU) takes an STM32F407 development board as a core, leads out external interfaces for the convenience of students to connect other sub-modules according to system construction requirements, reserves multiple types of peripheral interface such as I2C, SPI and UART, supports different communication protocol adaptation of the sensor module and the communication module and the like.

[0087] The debugging module mainly displays intermediate variable data through an OLED module 2 display and a ground station display, so as to facilitate students to monitor the hardware running state in real time and to perform debugging work in the flight control development process.

[0088] The sensor module is provided with various attitude (such as an MPU6050 module 4) and height (barometer 5) sensor modules for the flight control system. ​

[0089] Communication module, including SBUS receiver 6, realizing remote control instruction receiving; meanwhile including wireless serial port unit realizing more than 50 meters data transmission between core control module 1 and ground station.

[0090] Flight control output PWM module, by connecting the general-purpose timer multiplexing interface of the MCU selected by the student to the module, realizing centralized output of the electric control signal PWM, facilitating the unification of the output interface. The module supports at least 6-way PWM signal output.

[0091] Power module 7, configured with power protection module (including TVS transient suppression diode), main power supply interface (5V / 3.3V dual voltage output), the power module 7 adopts physical key position plus color coding standardized wiring terminal, uniformly adopts 2.54mm, the power supply end adopts red terminal, the communication end adopts blue terminal, preventing wrong connection.

[0092] Example 2, exemplary, the modular multi-rotor unmanned aerial vehicle flight control development teaching platform software system provided by the embodiment of the application has the following layered architecture design.

[0093] Develop three-layer software architecture based on STM32 standard library, each layer is independently packaged and called as needed, and the specific structure is as shown in Figure 5 , including:

[0094] Bottom driver layer 8, used for providing standardized drivers of each hardware system, including:

[0095] OLED display driver, attitude sensor data reading driver, remote control data reading driver, motor PWM control driver, wireless serial communication driver, etc. At the same time, the development document (including function, parameter description) is matched, which is convenient for users (students) to understand the operation logic of the hardware system.

[0096] For example:

[0097] void ADC_GpioInit(GPIO_TypeDef *GPIOx, uint32_t PINx)

[0098] Function: configure the specified pin as floating analog mode

[0099] Parameter: GPIO_TypeDef *GPIOx the port where the pin to be set is located

[0100] uint32 t PINx the pin number of the pin to be set

[0101] void ADC_InitConfig(ADC_TypeDef* ADCx.FunctionalState scanState,uint8t nbrConv)

[0102] Function: Set up ADC basic parameters, general parameters, enable clock

[0103] Parameter: ADC TypeDef* ADCx ADC to be set, can take values ADC1, ADC2, ADC3

[0104] Functional State scanState specifies whether to enable scan mode, take values ENABLE or DISABLE

[0105] uint8 t nbrConv conversion channel number of regular sequence, if scan mode is not enabled, set to 1

[0106] void ADC_ChannelConfig(ADC_TypeDef* ADCx.FunctionalState disDMA.DMA_Stream_TypeDef*DMAy_Streamx

[0107] Function: Configure the regular sequence to be converted, set whether to enable DMA

[0108] Parameter: ADC TypeDef* ADCx ADC to be set, can take values ADC1, ADC2, ADC3

[0109] Functional State disDMA specifies whether to enable DMA, can take values ENABLE or DISABLE

[0110] DMA_Stream TypeDef* DMAy_Streamx if enabled, specifies the data stream to be configured.

[0111] Data processing and control algorithm layer 9, used to realize core data processing and control functions, including:

[0112] Sensor data processing and solving module, provides Kalman filtering algorithm and basic principles of multi-sensor fusion method, etc. Students write data processing programs to process the raw data of MPU6050 attitude sensor 4 and MS5611 pressure sensor 5, write complementary fusion algorithm code to fuse accelerometer and gyroscope data, and write attitude sensor 4 and pressure sensor 5 calibration program, etc.

[0113] PID controller, the experimental guide book provides the PID control method and the structure principle of double ring PID, and the students compile the double ring PID control algorithm of attitude angular velocity and angle and the height ring PID control algorithm code based on the air pressure sensor 5 according to the theoretical knowledge;

[0114] Power solving module, the students compile the power distribution code according to the multi-rotor power solving equation, and the attitude expectation of three axes is solved into the PWM duty ratio control signal of 4, 6 motor.

[0115] Application layer 10, for coordinating the ground station, realizing task management and data display, including:

[0116] Flight data transmission and real-time display module, for being responsible for the encapsulation and transmission of different ground station protocols of flight data, and carrying out data storage;

[0117] Flight mode and automatic flight task management module, for realizing flight mode switching, and automatic task execution such as height keeping, point keeping and straight line motion.

[0118] Embodiment 3, the operability design of the hardware system: each module reserves key test points (such as sensor output end, PWM signal end), supports users (students) to directly measure signals using a multimeter, oscilloscope, and auxiliary fault troubleshooting; the module wiring uniformly adopts a line interface, which is convenient for students to master the connection relationship between hardware, and the time is less than or equal to 30 minutes, which is suitable for the teaching rhythm of the classroom.

[0119] Open design of software system: the software code annotation coverage is greater than or equal to 80%, the modular programming idea is adopted, the user (student) can directly call the bottom driver function of the bottom driver layer 8, and the function extension can be realized without modifying the core logic.

[0120] As shown in Figure 7 The test method of the modular multi-rotor unmanned aerial vehicle flight control teaching platform of the application comprises:

[0121] S1, the preparation of hardware system and software system is prepared;

[0122] Hardware system preparation: prepare the core control module 1, the debugging module, the sensor module, the communication module, the flight control output PWM module, the power module 7, the expansion module and the ground station, the supporting transmission line, the multimeter, the oscilloscope and other tools, and the power system equipment such as unmanned aerial vehicle motor and speed controller;

[0123] Software system preparation, install Keil MDK development environment, STM32 standard library, ground station monitoring software, build bottom driver layer 8, data processing and control algorithm layer 9, application layer 10 STM32 engineering file. In addition, prepare teaching resources: matching "module wiring manual", "driver development document", "experimental guide book".

[0124] S2, based on the prepared hardware system, software system, each module, multi-rotor unmanned aerial vehicle flight control phased hardware connection and software development work; see table 1;

[0125] Table 1 project design content distribution table

[0126] Stage 1, STM32-based control system development and debugging platform, including:

[0127] Step 1, hardware system building, students use physical key position plus color coding terminal, STM32F407 core control module 1 and debugging module OLED module 2 (I2C interface), wireless serial module 3 (USB serial module) connection, power supply end (5.0mm red terminal) 5V power supply, communication module (2.54mm blue terminal) I2C and USART interface, complete hardware system circuit building.

[0128] Step 2, software system building, through the call underlying driver layer 8 IIC serial driver and UART serial driver, write OLED display driver program, NRF24L01 serial transmission driver program, configure project environment in Keil MDK, compile and download the basic program, realize OLED display variable name and data, ground station can be connected with MCU serial port, can receive and send data.

[0129] Step 3, function verification, through the debugging OLED module 2 on-board OLED debugging window to view the displayed data name and value, ground station can be connected with serial port and display the data.

[0130] Stage 2, unmanned aerial vehicle attitude sensor data acquisition and processing;

[0131] Step a, sensor data acquisition, MPU6050 attitude sensor 4, MS5611 barometric pressure sensor 5 through I2C interface access core control module 1, through the call IIC serial driver, write attitude sensor data acquisition function, realize the original data acquisition through OLED and ground station detection output original angular velocity, acceleration, can be combined with improved algorithm or improved calculation formula to describe the implementation content;

[0132] Step b, attitude solution and filtering, write Kalman filter function and complementary fusion function, noise suppression to the original data, realize attitude solution (convert to pitch, roll, heading angle), through the improved algorithm or improved technical formula to describe the specific implementation process, for example, Kalman filter function and complementary fusion function can be supplemented by improved formula;

[0133] Phase 3, UAV communication system development;

[0134] Step (1), remote controller SBUS signal receiving and analysis, connect SBUS communication module to the UART interface of the core control module 1, call UART driver, write remote receiver data and SBUS analysis function, and analyze throttle, pitch, roll, and heading instructions.

[0135] Step (2), flight control and ground station data communication test, modify NRF24L01 communication unit code, realize flight parameter and ground station display driving data transmission of core control module 1 (flight control) through data encapsulation, and verify stable communication within 50 meters (data packet loss rate ≤1%).

[0136] Phase 4, UAV power drive system development;

[0137] Step (i), motor drive system development, connect PWM drive module (maximum support 6 output) to core control module 1, call bottom layer 8 PWM timer driver, write motor drive code, drive rotor motor rotation, use oscilloscope to measure PWM signal duty cycle (accuracy ≤1%).

[0138] Step (ii), power solution module development, write data processing and control algorithm layer 9 power solution program, convert attitude command to 4, 6 way motor PWM duty cycle, realize instruction and power mapping, verify linear correspondence between motor speed and instruction.

[0139] Phase 5, UAV control algorithm design and development;

[0140] Step (I), angular velocity loop PID design, write PID controller, debug angular velocity loop PID parameters, write program to realize sensor data, angular velocity control, and closed loop logic of motor output, modify parameters in real time through ground station, test angular velocity response time ≤100ms.

[0141] Step (II), angle loop PID design, superimpose angle loop PID control, build double loop PID control logic, test UAV attitude control accuracy (angle error ≤0.5°), record control effect under different parameters.

[0142] Phase 6, overall test of UAV control system;

[0143] Step one, PID parameter tuning, users (students) adjust angular velocity loop and angle loop PID parameters through parameter adjustment interface reserved by ground station, complete hovering test of quadrotor UAV (fixed point hovering error ≤1 meter).

[0144] Step two, data analysis, the remote control desired attitude data and the actual control attitude angle detected by the attitude sensor 4 are sent to the ground station data display and analysis page, the change curve is drawn by the curve drawing plug-in, and the attitude control performance is analyzed in real time; at the same time, the ground station data storage function is started, the flight data (CSV format) is exported, the stability of the attitude and height data is analyzed, and the experiment is completed.

[0145] S3, through the above phased implementation, the user (student) completes the whole process from hardware system building, software system software programming to testing;

[0146] For example, the user can master the underlying principles and development skills of the flight control system; the error-proof design and open architecture of the platform effectively reduce the operation and development threshold, and adapt to the needs of large-scale teaching.

[0147] To further illustrate the effects of the embodiments of the application, the following experiments are performed.

[0148] Compared with the existing unmanned aerial vehicle product flight control teaching equipment, the modular multi-rotor unmanned aerial vehicle flight control teaching platform breaks through the inherent limitation of the existing commercial unmanned aerial vehicle black box, and through modularization and plug-in design, students can directly contact the flight control core components, clarify the underlying circuit and signal transmission logic, effectively solve the pain point of the disconnection between industry technology and teaching, fill the gap of unmanned aerial vehicle professional teaching resources, and the supporting whole process practice system enables students to independently complete hardware building, programming debugging and other operations, and truly realizes the integration of teaching, learning, doing and creating.

[0149] In terms of convenience and safety, the effect is also particularly outstanding: during the research and development stage, general standardized components and STM32 standard library are used, which reduces the research and development difficulty and cost, compared with the complex Pixhawk open source secondary development system, the teaching threshold is greatly reduced, which is suitable for beginners and classroom teaching scenes, and avoids the disadvantages of single function of traditional principle verification type equipment.

[0150] In terms of adaptability and expansibility, its advantages are far superior to existing technologies: hardware reserves multiple types of peripheral interfaces, and software uses a layered independent packaging architecture, which can adapt to the teaching needs of different universities and multiple majors, support student innovation and development, and realize one research and development, multiple scene reuse; at the same time, the economic advantage is obvious, the use of general components controls the cost of a single device, and the modular assembly method is convenient for batch configuration in university laboratories, which is more suitable for large-scale promotion than existing special teaching equipment, and truly takes into account the practicality, economy and innovation of teaching.

[0151] The above merely describes the preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any modification, equivalent replacement and improvement within the technical range disclosed by the present application and within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A modular multi-rotor UAV flight control development and teaching platform, characterized in that, The platform includes: The hardware system breaks down the flight control hardware system into independent sub-modules. These sub-modules are connected through standardized signal connection interfaces and pluggable interfaces to form a complete flight control hardware system. This system is used for the design of UAV flight control systems, allowing for direct contact with core flight control components, clarification of underlying flight control circuitry and signal transmission logic, measurement of multi-rotor UAV operating signals at test points reserved in the sub-modules, and detection of flight control faults. The software system adopts a modular, layered software architecture for phased design and development of flight control software for multi-rotor UAVs. The teaching system, through the progressive design of experimental projects, is used to progress from the hardware driver layer to the data processing layer to the application layer (10), with the code progressing from the bottom layer to the top layer, and the theoretical difficulty increasing step by step.

2. The modular multi-rotor UAV flight control development and teaching platform according to claim 1, characterized in that, The hardware system includes: The core control module (1) is connected to the debugging module, sensor module, flight control output PWM module and communication module through the reserved I2C, SPI and UART peripheral interfaces, and is used to issue multi-rotor UAV operation status control commands to the above modules; The debugging module integrates an OLED module (2) and a wireless serial port module (3) for users to monitor the operating status of the core control module (1), sensor module, flight control output PWM module and communication module in real time. The sensor module integrates an attitude sensor (4) and a barometric pressure sensor (5), and communicates with the core control module (1) through an I2C / SPI interface; the original signals of the attitude sensor (4) and the barometric pressure sensor (5) are measured using an oscilloscope device through the data test points. The communication module includes an SBUS receiver (6) to receive remote control commands and to transmit data between the core control module (1) and the ground station via a wireless serial port unit (3). The flight controller outputs a PWM module to drive the multi-rotor drone.

3. The modular multi-rotor UAV flight control development and teaching platform according to claim 2, characterized in that, The hardware system also includes: The power module (7) is equipped with a power protection module and a main power supply interface. It uses physical key positions and color-coded standardized wiring terminals to supply power to the above modules.

4. The modular multi-rotor UAV flight control development and teaching platform according to claim 3, characterized in that, The hardware system also includes an expansion module, which connects to optical flow sensor, ultrasonic sensor, GPS / BeiDou positioning sensor and communication expansion module peripherals through the I2C, SPI and UART universal interfaces reserved in the core control module (1), providing extended content for different functional experiments of multi-rotor UAV.

5. The modular multi-rotor UAV flight control development and teaching platform according to claim 2, characterized in that, The OLED module (2) includes an on-board OLED debugging window.

6. The modular multi-rotor UAV flight control development and teaching platform according to claim 1, characterized in that, The software system includes: The hardware driver layer (8) is used to provide standardized drivers for various hardware systems; The data processing and control algorithm layer (9) is used to implement the core data processing and control functions; The application layer (10) is used in conjunction with the ground station to realize task management and data display.

7. The modular multi-rotor UAV flight control development and teaching platform according to claim 6, characterized in that, The hardware driver layer (8) integrates OLED display driver, attitude sensor (4) data reading driver, remote control data reading driver, motor PWM control driver, and wireless serial communication driver. It also comes with driver development documentation, including function functions and parameter descriptions.

8. The modular multi-rotor UAV flight control development and teaching platform according to claim 6, characterized in that, The data processing and control algorithm layer (9) includes: a sensor data processing and calculation module, which integrates a Kalman filter algorithm to suppress noise in the raw data of the attitude sensor (4) and the barometer (5), integrates a complementary fusion algorithm to perform fusion processing of accelerometer and gyroscope data, and a calibration procedure for the attitude sensor (4) and the barometer (5). The PID controller provides attitude PID control algorithms for attitude angular velocity and angle, and position loop PID control algorithms based on optical flow sensor and barometric pressure sensor (5). It also provides a quick parameter adjustment interface and supports real-time modification of PID parameters through the ground station. The power calculation module is used to convert the control commands for power distribution and redundant control into the PWM duty cycles of 4 and 6 motors.

9. The modular multi-rotor UAV flight control development and teaching platform according to claim 6, characterized in that, The application layer (10) includes: The flight data transmission and real-time display module is responsible for encapsulating and transmitting flight data according to different ground station protocols, as well as storing the data. The flight mode and automatic flight mission management module is used to switch flight modes and execute automatic missions such as altitude hold, point hold, and linear motion.

10. A testing method for a modular multi-rotor UAV flight control teaching platform, characterized in that, The method implemented in the modular multi-rotor UAV flight control teaching platform according to any one of claims 1-9 includes the following steps: S1, prepare the hardware and software systems; S2, based on the prepared hardware and software system modules, performs phased control of multi-rotor UAV flight control. S3, through the above phased implementation, completes the entire process from hardware system construction, software programming, and testing.

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