Unmanned aerial vehicle flight control system based on domestic MCU

Abstract

An unmanned aerial vehicle flight control system based on a domestic MCU comprises a navigation resolving chip and a control resolving chip which communicate through a serial port, a first external clock circuit electrically connected with the navigation resolving chip, a second external clock circuit electrically connected with the control resolving chip, and a third external clock circuit electrically connected with the second external clock circuit. The system comprises a navigation resolving chip, a control resolving chip connected with the navigation resolving chip, a first simulation interface circuit connected with the navigation resolving chip through an SW interface, a first simulator connected with the first simulation interface circuit, a second simulation interface circuit connected with the control resolving chip through an SW interface, and a second simulator connected with the second simulation interface circuit, the system comprises a navigation resolving chip, a control resolving chip, a first data communication interface circuit connected with the navigation resolving chip, a second data communication interface circuit connected with the control resolving chip, a power supply module for supplying power to each chip, a first sensor module connected with the navigation resolving chip, and a second sensor module connected with the control resolving chip.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and in particular to a flight control system for unmanned aerial vehicles based on a domestically produced MCU. Background Art

[0002] Unmanned aerial vehicles (UAVs), an aircraft mainly controlled by radio remote control or its own program, are widely used for tracking, positioning, communication, telemetry, information collection and other tasks due to their small size, low cost, ease of use and accuracy. The flight control system of a UAV is the core system for the entire flight process of the UAV, including take-off, air flight, mission execution and return recovery.

[0003] The most common flight control system for rotary-wing UAVs on the market is the Pixhawk series flight control system, which uses an ARM chip from a foreign semiconductor company. Domestic chip supply cannot be independently controlled. In addition, the common flight control systems in technology, including the Pixhawk series flight control, use a main control MCU, which is required to perform both navigation and control calculations. Both are programs that take up a lot of computing resources. Therefore, there are high requirements for the scheduling of flight control system program software, and the program design and development are complex, and there is a problem of navigation and control competing for computing resources. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the technical problem to be solved by the present invention is how to provide a UAV flight control system based on a domestic MCU, and solve the problem of competition for computing resources between the UAV flight control navigation solution and the control solution, thereby greatly reducing the difficulty of developing the flight control program.

[0005] In order to solve the above technical problems, the UAV flight control system based on the domestic MCU provided by the present invention includes a navigation solution chip and a control solution chip communicating through a serial port, a first external clock circuit electrically connected to the navigation solution chip, a second external clock circuit electrically connected to the control solution chip, a first simulation interface circuit connected to the navigation solution chip through a SW interface, a first simulator connected to the first simulation interface circuit, a second simulation interface circuit connected to the control solution chip through a SW interface, a second simulator connected to the second simulation interface circuit, a first data communication interface circuit connected to the navigation solution chip, a second data communication interface circuit connected to the control solution chip, and a circuit for providing power to each chip. A source module, a first sensor module connected to a navigation solution chip, and a second sensor module connected to a control solution chip; the navigation solution chip is connected to sensors including an inertial measurement unit, a barometric altimeter and a satellite navigation module, receives sensor data and performs navigation solution, and the obtained navigation information including attitude, position and speed information is sent to the control solution chip through a serial port for flight control solution. When the control solution chip is started, the navigation initial binding parameters are transmitted to the navigation solution chip, and the control solution chip solves the control instructions and transmits them to the response execution mechanism. The two chips cooperate with each other, operate independently, and exchange data through the serial port. The navigation solution chip and the control solution chip are used to separate the navigation solution program from the control solution program.

[0006] As a further improved technical solution, the present invention provides a UAV flight control system based on a domestic MCU, wherein the first external clock circuit and the second external clock circuit both include a passive crystal oscillator clock circuit connected to a navigation solver chip or a control solver chip.

[0007] As a further improved technical solution, the present invention provides a UAV flight control system based on a domestic MCU, wherein the first data communication interface circuit and the second data communication interface circuit both include a USB communication interface circuit, an RS422 interface circuit, an RS232 interface circuit, a CAN interface circuit and an SPI interface.

[0008] As a further improved technical solution, the present invention provides a UAV flight control system based on a domestic MCU, wherein the power module includes an external 12V power supply, a first voltage conversion circuit that converts the 12V power supply into 5V, and a second voltage conversion circuit that converts the 12V power supply into 3.3V.

[0009] The technical solution provided by the present invention designs a UAV flight control system based on the domestic MCU independently developed and produced. The present invention adopts two chips for navigation solution and control solution respectively. The chip used for navigation solution receives data from sensors such as IMU, barometric altimeter and satellite navigation for solution, and then transmits the UAV attitude, position, speed, angular velocity and other information to another chip through the serial port for control solution, thereby solving the problem of UAV flight control navigation solution and control solution competing for computing resources, and greatly reducing the difficulty of flight control program development. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the present application, but do not constitute an improper limitation of the present invention. In the accompanying drawings: Figure 1 This is a schematic diagram of the control solution chip circuit of the embodiment; Figure 2 The circuit schematic diagram of the chip for example navigation solution; Figure 3 is a schematic diagram of an external clock circuit in an embodiment; Figure 4 Schematic diagram of the connection relationship between the navigation solution chip and the control solution chip in the embodiment; Figure 5 is a schematic diagram of a simulation interface circuit diagram in an embodiment; Figure 6 is a schematic diagram of a USB communication interface circuit in an embodiment; Figure 7 It is the RS422 interface circuit schematic diagram in the embodiment; Figure 8 It is the RS232 interface circuit schematic diagram in the embodiment; Fig. 9 It is a schematic diagram of the CAN interface circuit in the embodiment; Fig.10 It is a schematic diagram of a 12V to 5V circuit diagram in an embodiment; Fig.11 It is a schematic diagram of a 5V to 3.3V circuit diagram in an embodiment; Fig.12 1 is a schematic diagram of a barometric altimeter circuit in an embodiment. Implementation

[0011] The present invention will be further described below in conjunction with the accompanying drawings.

[0012] The UAV flight control system based on the domestic MCU provided by the present invention includes a navigation solution chip QJ32F405RGT6 and a control solution chip QJ32F407VGT6, which communicate through a serial port, thereby solving the problem of competing for computing resources and reducing the difficulty of developing a flight control program. In addition to the navigation solution chip QJ32F405RGT6 and the control solution chip QJ32F407VGT6, the UAV flight control system based on the domestic MCU also includes a first external clock circuit electrically connected to the navigation solution chip QJ32F405RGT6, a second external clock circuit electrically connected to the control solution chip QJ32F407VGT6, a first simulation interface circuit connected to the navigation solution chip QJ32F405RGT6 via a SW interface, and a first simulator (ST-LINK) connected to the first simulation interface circuit. , a second simulation interface circuit connected to the control solver chip QJ32F407VGT6 through a SW interface, a second simulator (ST-LINK) connected to the second simulation interface circuit, a first data communication interface circuit connected to the navigation solver chip, a second data communication interface circuit connected to the control solver chip, a power module for providing power to each chip, a first sensor module connected to the navigation solver chip, and a second sensor module connected to the control solver chip; using the navigation solver chip and the control solver chip, the navigation solver program is separated from the control solver program.

[0013] The navigation solver chip QJ32F405RGT6 and the control solver chip QJ32F407VGT6 are used for navigation and control respectively. The navigation solver chip receives data from sensors such as IMU, barometric altimeter and satellite navigation, and obtains the required navigation data, including the attitude, position, speed, angular velocity, acceleration, etc. of the UAV, which are transmitted to the control solver chip through the serial port. The control solver chip obtains the control command according to the designed control algorithm program and transmits it to the response actuator. The response actuator (including servo, motor, etc.) executes the action according to the command, thereby realizing the control of the UAV by the flight control system.

[0014] As one embodiment, the present invention provides a UAV flight control system based on a domestic MCU, wherein the first external clock circuit and the second external clock circuit both include a passive crystal oscillator clock circuit connected to a navigation solution chip or a control solution chip.

[0015] As one embodiment, the present invention provides a UAV flight control system based on a domestic MCU, wherein the first data communication interface circuit and the second data communication interface circuit both include a USB communication interface circuit, an RS422 interface circuit, an RS232 interface circuit, a CAN interface circuit and an SPI interface.

[0016] As one embodiment, the present invention provides a UAV flight control system based on a domestic MCU, wherein the power module includes an external 12V power supply, a first voltage conversion circuit that converts the 12V power supply into 5V, and a second voltage conversion circuit that converts the 12V power supply into 3.3V.

[0017] Specifically, Figure 1 As shown, the control solution chip uses QJ32F407VGT6 chip, such as Figure 2 As shown in the figure, the navigation solution microcontroller adopts QJ32F405RGT6 chip, and the two communicate through RS422 serial port, which solves the problem of competing for computing resources and reduces the difficulty of developing flight control program.

[0018] like Figure 3 As shown in the figure, the navigation solution chip is connected to sensors such as the inertial measurement unit (IMU), barometric altimeter, and satellite navigation module, receives sensor data and performs navigation solution. The navigation information obtained, including attitude, position, speed, etc., is sent to the control solution chip through the serial port for flight control solution. The control solution chip needs to transmit the navigation initial binding parameters to the navigation solution chip when it starts. The two chips work together, operate independently, and exchange data through the serial port.

[0019] The reference clocks of QJ32F407VGT6 and QJ32F405RGT6 chips include internal reference clock and external reference clock. The internal reference clock is HIS, which is an RC oscillator with a frequency of 16MHz integrated in the chip. Figure 4 As shown, the external reference clock HSE is input through the pins OSC_IN and OSC_OUT. In the embodiment, both MCUs use an external clock as the system clock, and an external 24MHz passive crystal oscillator is used as the clock source. When arranged, it is as close to the MCU as possible to avoid external interference.

[0020] Simulation debugging is a necessary condition for flight control software development. When debugging the program, the simulator simulates and debugs the microcontroller (MCU) through the SW interface. SW has functions such as program test burning, memory reading and writing, system task monitoring, and FLASH content reading. A compatible simulator must be equipped to link the compilation environment through the simulator. The SW interface pins are SWDIO and SWCLK. The simulators used by the two MCUs of the present invention are both ST-LINK. The interface circuit is as follows: Figure 5 shown.

[0021] Data communication interface: The communication interfaces used by the control solution chip include serial port (RS422 and RS232), SPI, and USB interface. The communication interfaces used by the navigation solution chip include serial port, CAN, and SPI. The external circuits used by the same type of interface are consistent. The USB data communication interface circuit used in the embodiment is as follows: Figure 6 As shown; the USB interface pins are VBus, DM, DP and GND. When the USB interface is connected to the PC, the VBus pin can generate a stable 5V power supply. DM and DP are two differential signal lines for data transmission. NUF2042XV6T1 is used in the circuit for USB interface electrostatic discharge, which plays a certain protective role. The serial ports used in the embodiment include RS422 and RS232. The RS422 data communication interface circuit used is as shown in FIG. Figure 7 As shown, the RS232 data communication interface circuit used is as follows Figure 8 As shown. RS422 uses ISO1432DW chip, which has isolation function and can convert TTL level signal from processor into RS422 level signal A, B, Z, Y through TxD and RxD input; RS232 uses MAX3232EUE+ chip, which does not have isolation function and needs to be used with ISO7721D, powered by 5V power supply, and the charge pump needs four 0.1uF energy storage capacitors. T1IN receives TTL level signal from MCU and converts it into RS232 level signal, which is output to external device through T1OUT, and R1IN receives RS232 level of external device and converts it into TTL level signal, which is transmitted to MCU through R1OUT.

[0022] The navigation solution QJ32F405RGT6 chip itself has a CAN controller, and only needs an external CAN transceiver to realize the CAN interface communication function, such as Fig. 9 As shown, the CAN transceiver selected in the embodiment is ISO1050, and a 120Ω terminal resistor is connected between the CANH and CANL pins to improve the anti-interference capability and enhance the signal quality.

[0023] The navigation solver chip QJ32F405RGT6 and the control solver chip QJ32F407VGT6 both integrate SPI interfaces, do not require a transceiver, and only require direct connection of external devices.

[0024] The stable and effective supply of power voltage is the premise for the normal operation of the entire flight control system. The power supply voltages required by the embodiment include 12V, 5V, and 3.3V, of which 12V is powered by an external power supply and is the power input of the entire flight control system. 5V and 3.3V are the power supplies for each chip of the flight control system. Therefore, the external input 12V voltage needs to be converted into the required 5V and 3.3V power supplies. The 12V to 5V circuit schematic diagram is shown in FIG. Fig.10 As shown in the figure, the DC-DC chip selected is TPS54360B. The capacitors at the input and output are mainly set to reduce ripples to improve power supply performance. The schematic diagram of the 5V to 3.3V circuit is as follows Fig.11As shown, the LTI963AES8-3.3#PBE chip is selected. This chip has fast transient response and low output voltage noise, and is very suitable for use in flight control systems as a 3.3V power supply. In addition, a power isolation chip DCP020505U needs to be added to the 5V power supply to protect other chips.

[0025] In addition to a microcontroller (MCU) and a power module, a complete drone flight control system also requires some sensors for measurement, including an inertial measurement unit (IMU), a satellite navigation module, a barometric altimeter, etc. In the embodiment, the inertial measurement unit (IMU) uses the MSI310F of Mattel Technology, and the satellite navigation module uses the UM982 of Unicore Starlink. They can be used by connecting to the corresponding interface of the flight control system. The barometric altimeter uses the WXP380 chip of Wuxin Hi-Tech, and its circuit schematic diagram is shown below. Fig.12 WXP380 is a capacitive MEMS pressure chip with low power consumption, low offset, and low noise performance. The resolution can reach 2cm. The chip operating voltage is 1.7-3.6V, and the actual power supply is 3.3V to work normally.

[0026] The technical solution provided by the present invention is based on the UAV flight control system designed with domestic MCU (QJ32F407VGT6 and QJ32F405RGT6), which reduces the risk of using foreign chips. The navigation solution and control solution are divided into two microcontrollers (MCU) for independent calculation, which reduces the difficulty of flight control program development.

[0027] For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the claims of the present invention shall be included in the protection scope of the present invention.

Claims

1. A UAV flight control system based on domestic MCU, characterized in that: It includes a navigation solution chip and a control solution chip communicating through a serial port, a first external clock circuit electrically connected to the navigation solution chip, a second external clock circuit electrically connected to the control solution chip, a first simulation interface circuit connected to the navigation solution chip through a SW interface, a first simulator connected to the first simulation interface circuit, a second simulation interface circuit connected to the control solution chip through a SW interface, a second simulator connected to the second simulation interface circuit, a first data communication interface circuit connected to the navigation solution chip, a second data communication interface circuit connected to the control solution chip, a power supply module for providing power to each chip, and a first sensor connected to the navigation solution chip. A sensor module, a second sensor module connected to the control solution chip; the navigation solution chip is connected to sensors including an inertial measurement unit, a barometric altimeter and a satellite navigation module, receives sensor data and performs navigation solution, and the obtained navigation information including attitude, position and speed information is sent to the control solution chip through the serial port for flight control solution. When the control solution chip is started, the initial binding parameters of the navigation are transmitted to the navigation solution chip. The control solution chip solves the control command and transmits it to the response execution mechanism. The two chips cooperate with each other, operate independently, and exchange data through the serial port. The navigation solution chip and the control solution chip are used to separate the navigation solution program from the control solution program.

2. The UAV flight control system based on domestic MCU according to claim 1 is characterized in that: The first external clock circuit and the second external clock circuit both include a passive crystal oscillator clock circuit connected to the navigation solution chip or the control solution chip.

3. The UAV flight control system based on domestic MCU according to claim 1 is characterized in that: The first data communication interface circuit and the second data communication interface circuit both include a USB communication interface circuit, an RS422 interface circuit, an RS232 interface circuit, a CAN interface circuit and an SPI interface.

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