CN105700540A - FPGA-based unmanned plane flight control circuit - Google Patents

Abstract

The invention provides an FPGA-based UAV flight control circuit, including: a controller module, a nine-axis measurement module, an attitude calculation module, a PID control module, and a remote control servo module, wherein the nine-axis measurement module, the attitude solution The calculation module, the PID control module and the remote control servo module are electrically connected in turn; the nine-axis measurement module is used to generate and output nine-axis data according to the measurement data transmitted by the accelerometer, gyroscope and the magnetometer; the attitude calculation module is used to generate and output nine-axis data according to the The nine-axis data generates and outputs flight attitude data; the PID control module is used to calculate and generate motor control data based on the nine-axis data and flight attitude data, and the remote control servo module is used to control the electronic governor based on remote control signals and motor control data. control signal. The FPGA-based UAV flight control circuit of the present invention realizes parallel control of each motor of the UAV by using the FPGA as a microcontroller, thereby improving the accuracy and real-time performance of motor control.

Description

FPGA-based UAV flight control circuit

technical field

The invention relates to the technical field of unmanned aerial vehicles, in particular to an FPGA-based flight control circuit for unmanned aerial vehicles.

Background technique

The flight control circuit of a general multi-rotor UAV includes a control chip, an inertial measurement circuit, an electronic compass, a barometer, a PWM input signal module, a PWM output signal module, a GPS module, and serial RS232 or I2C interfaces. Among them, the control chip mostly adopts MCU (Microcontroller Unit, micro-control circuit) or DSP (Digital Signal Processor, digital signal processor), even if some use FPGA, FPGA is only used to expand the IO interface. That is to say, the current flight control algorithms in multi-rotor UAVs are all in a serial manner, which cannot accurately and parallelly control the motors of multi-rotor UAVs, and the accuracy and real-time performance of motor control are poor.

Contents of the invention

In view of the status quo of the prior art, the purpose of the present invention is to provide an FPGA-based UAV flight control circuit, which can control the various motors of the UAV in parallel, thereby improving the accuracy and real-time performance of motor control.

To achieve the above object, the present invention adopts the following technical solutions:

An FPGA-based UAV flight control circuit, comprising: a controller module and a nine-axis measurement module electrically connected to the controller module, an attitude calculation module, a PID control module and a remote steering gear module, wherein the The nine-axis measurement module, the attitude calculation module, the PID control module and the remote control servo module are electrically connected in sequence;

The nine-axis measurement module is connected to an accelerometer, a gyroscope, and a magnetometer, and is used to generate and output nine-axis data according to measurement data transmitted by the accelerometer, the gyroscope, and the magnetometer;

The attitude calculation module is used to generate and output flight attitude data according to the nine-axis data;

The PID control module is connected to the nine-axis measurement module, and the PID control module includes at least three attitude angle control circuits arranged in parallel for transmitting the nine-axis data and the flight attitude data according to the nine-axis measurement module. Calculate and generate motor control data;

The remote control servo module is connected to the remote control receiver and the electronic governor connected to each motor of the drone, and the remote control servo module is used to control the The motor control data output by the module generates a control signal for controlling the electronic governor, and feeds back the control signal to the PID control module to control the operation of each motor of the drone in parallel.

In one embodiment of the present invention, the nine-axis measurement module includes an interrupt control circuit and a data buffer circuit, a data processing circuit, a data gating circuit, a data restoration circuit and a synchronous output circuit electrically connected in sequence;

Wherein, the data buffer circuit, the data processing circuit and the synchronous output module are connected to the controller module; the interrupt control circuit is connected to the data gating circuit and the data restoration circuit, and is used to control the Turn on or off of the data strobe circuit;

The data buffer circuit is connected to the accelerometer, the gyroscope and the magnetometer to obtain the measurement data of the accelerometer, the gyroscope and the magnetometer, and the data processing circuit is used for The measurement data is filtered, the data restoration circuit is used to perform digital conversion and normalization processing on the measurement data, the synchronization output module is connected to the attitude calculation module, and the synchronization output circuit is used for Synchronously generate the nine-axis data, and transmit the nine-axis data to the attitude calculation module.

In one embodiment of the present invention, the data processing circuit includes an accelerometer data processing unit, a gyroscope data processing unit and a magnetometer data processing unit;

The accelerometer data processing unit includes a first smoothing filter bank and a first data gate electrically connected in sequence, for smoothing and filtering the measurement data of the accelerometer;

The gyroscope data processing unit includes a second smoothing filter bank, a zero bias value calculation-elimination circuit and a second data gate, which are electrically connected in sequence, for smoothing and filtering the measured data of the gyroscope, eliminating zero Handling of partial values;

The magnetometer data processing circuit includes a third smoothing filter bank, a calibration-normalization circuit and a third data gate that are electrically connected in sequence, and are used to smooth filter and calibrate the measurement data of the magnetometer;

Wherein, the first data strobe, the second data strobe and the third data strobe are respectively connected to the controller module.

In one embodiment of the present invention, the attitude calculation module includes an accelerometer error measurement circuit, a magnetometer error measurement circuit, a gyroscope error measurement circuit, a quaternion update circuit, an attitude transformation matrix update circuit, and an attitude angle conversion circuit ;

Both the accelerometer error measurement circuit and the magnetometer error measurement circuit are connected to the gyroscope error measurement circuit, and the gyroscope error measurement circuit is electrically connected to the quaternion update circuit and the attitude conversion matrix update circuit in turn. circuit and the attitude angle conversion circuit;

The gyroscope error measurement circuit is used to generate the accelerometer error value generated by the accelerometer error measurement circuit, the magnetometer error value generated by the magnetometer error measurement circuit, and the measurement data of the gyroscope through a complementary filtering algorithm Gyroscope correction data;

The quaternion update circuit is used to generate a new quaternion value according to the gyroscope correction data and the last quaternion value; the attitude transformation matrix update circuit is used to generate an attitude matrix according to the new quaternion value , and feed back the new quaternion value to the accelerometer error measurement circuit and the magnetometer error measurement circuit; the attitude angle conversion circuit is used to generate an attitude angle according to the attitude matrix.

In one embodiment of the present invention, the PID control module includes an output control circuit and three attitude angle control circuits arranged in parallel, and the three attitude angle control circuits are respectively a pitch angle control circuit and a roll angle control circuit and yaw angle control circuit;

The pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit are respectively connected to the attitude calculation module, the nine-axis measurement module and the output control circuit; the output control circuit outputs the The motor control data is fed back to the pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit.

In one embodiment of the present invention, the pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit all adopt a double-loop structure.

In one embodiment of the present invention, the remote control servo module includes a receiving circuit, a motor control circuit, and a channel encoding circuit; the receiving circuit is connected to the motor control circuit and the channel encoding circuit, and the motor control circuit, The channel encoding circuit is connected to the controller module;

The receiving circuit is connected to the remote controller receiver, and is used for receiving the remote control signal sent by the remote controller and including multiple channel data, and respectively processing the multiple channel data of the remote control signal; the channel encoding circuit is used for Generate a control signal for the UAV working mode according to the remote control signal, and transmit the UAV working mode signal to the controller module;

The motor control circuit is connected to the PID control module, and the motor control circuit generates the channel value of the motor according to the motor control data output by the PID control module and the UAV working mode signal, and sends the motor The numerical value of the channel is converted into a control signal for controlling the electronic governor.

In one embodiment of the present invention, it also includes a barometer reading-compensation module connected with the barometer;

The barometer reading-compensation module includes an initialization circuit, a data reading circuit, a fourth data strobe, a temperature compensation circuit, an AD coefficient normalization circuit and a digital conversion circuit electrically connected to the controller module respectively ;

The fourth data strobe is connected to the barometer, the initialization circuit and the data reading circuit are connected to the fourth data strobe, the data reading circuit, the temperature compensation circuit, The AD coefficient normalization circuit and the digital system conversion circuit are electrically connected in sequence, and the digital system conversion circuit is used to output air pressure value and temperature value.

In one embodiment of the present invention, it also includes a GPS module and a data fusion module;

The barometer reading-compensation module and the GPS module are all connected to the data fusion module, and the data fusion module is electrically connected to the remote steering gear module and the attitude calculation module;

The GPS module is used to obtain the positioning information of the drone, and the data fusion module is used to read the air pressure value, the temperature value output by the compensation module according to the barometer, the positioning information output by the GPS module, and The flight attitude data generated by the attitude calculation module generates the motor control data.

In one embodiment of the present invention, it also includes a timer module, a reset module and a button module electrically connected to the controller module;

The button module is connected with the control buttons and display lights of the peripherals, and the display lights are used to indicate the working status of the drone.

In one embodiment of the present invention, the FPGA-based flight control circuit of the UAV is connected with the upper computer in communication.

The beneficial effects of the present invention are:

The unmanned aerial vehicle flight control circuit based on FPGA of the present invention, by adopting FPGA as micro-controller, and is provided with the attitude solving module and obtains the flight attitude data of unmanned aerial vehicle in real time, and the PID control module is used for according to flight attitude data and nine axis The nine-axis data transmitted by the measurement module is calculated to generate motor control data, and the remote control servo module generates control signals according to the motor control data to realize parallel control of each motor of the drone. At the same time, because the parallel processing speed of FPGA is much higher than that of micro The serial processing speed of the controller, therefore, through the FPGA control platform, shortens the calculation time of the flight control circuit, thereby improving the accuracy and real-time performance of the motor control, and laying the foundation for the development of the UAV flight control chip.

Description of drawings

Fig. 1 is the functional block diagram of an embodiment of the unmanned aerial vehicle flight control circuit based on FPGA of the present invention;

Fig. 2 is the functional block diagram of an embodiment of the nine-axis measurement module in the flight control circuit of the present invention;

Fig. 3 is a schematic diagram of the operation of reading measurement data of an embodiment of the nine-axis measurement module in the flight control circuit of the present invention;

Fig. 4 is the functional block diagram of an embodiment of the attitude calculation module in the flight control circuit of the present invention;

Fig. 5 is the functional block diagram of an embodiment of the PID control module in the flight control circuit of the present invention;

Fig. 6 is a control process diagram of an embodiment of the PID control module in the flight control circuit of the present invention;

Fig. 7 is the functional block diagram of an embodiment of the remote steering gear module in the flight control circuit of the present invention;

Fig. 8 is a functional block diagram of an embodiment of the barometer reading-compensation module in the flight control circuit of the present invention;

FIG. 9 is a flow chart of the initialization of the barometer reading-compensation module and the operation of data reading in the flight control circuit of the present invention.

detailed description

In order to make the technical solution of the present invention clearer, the FPGA-based UAV flight control circuit of the present invention will be further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are only used to explain the present invention and not to limit the present invention. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

As shown in FIG. 1 , the present invention provides an FPGA-based UAV flight control circuit, which can be used for flight control of UAVs such as multi-rotor UAVs or fixed-wing UAVs. The FPGA-based UAV flight control circuit. The flight control circuit of the present invention adopts the FPGA chip as the main micro-control unit, including a controller module 100, a nine-axis measurement module 200, an attitude calculation module 300, a PID control module 400, a remote steering gear module 500, and a barometer reading-compensation Module 600 , GPS module 700 , data fusion module 800 , timer module 110 , reset module 120 and key module 900 .

Wherein, the timer module 110, the reset module 120 and the button module 900 are all connected to the controller module 100; in this embodiment, the beat frequency of the timer module 110 can be 5ms to provide a stable timing beat. The reset module 120 is used to provide a stable reset signal and a clock signal for each circuit module of the flight control circuit, wherein the frequency of the clock signal can reach 100 MHz. The GPS module 700 is used to obtain the real-time positioning information of the drone. The controller module 100 is used as the top-level module of the flight control circuit, and is used to regulate the input and output of all modules under the beat of the timer module 110 and control the initialization of each module.

The nine-axis measurement module 200, the attitude calculation module 300, and the PID control module 400 are electrically connected to the controller module 100. The controller module 100 is used to control the initialization and other operations of the above-mentioned modules. The nine-axis measurement module 200 and the attitude calculation module 300 . The PID control module 400 can feed back the output measurement data to the controller module 100, so that the controller module 100 can control its flight attitude in real time according to the flight parameters of the drone. Specifically, the nine-axis measurement module 200, the attitude calculation module 300, the PID control module 400, and the remote control servo module 500 are electrically connected in sequence, and the nine-axis measurement module 200 is connected to an accelerometer, a gyroscope, and a magnetometer for use in accordance with the accelerometer. , gyroscope, and magnetometer transmit measurement data to generate and output nine-axis data.

In this embodiment, the accelerometer is a three-axis accelerometer, the gyroscope is a three-axis gyroscope, and the magnetometer is a three-axis magnetometer. Therefore, the nine-axis measurement module 200 outputs nine-axis data. Among them, the three-axis accelerometer is used to sense the acceleration of the UAV in the three-axis direction of the body coordinate system, and is mainly used to detect the three-axis movement of the UAV. The three-axis gyroscope is used to calculate the angular velocity of the drone in the three-axis direction of the body coordinate system according to the angle between the vertical axis of the internal gyro rotor and the drone, so as to distinguish the drone in the three-axis direction The motion state of the drone, the three-axis accelerometer and the three-axis gyroscope are mainly used to determine the pitch angle and roll angle of the drone. The three-axis magnetometer is used to correct the spin caused by the zero drift of the gyroscope. It is mainly used to correct the Z-axis measurement data of the gyroscope, that is, the measurement data of the yaw angle. Therefore, the three-axis magnetometer is mainly used to determine the machine's pointing direction. The nine-axis measurement module 200 is connected to the accelerometer, gyroscope and magnetometer through the I2C bus to read the measurement data of sensors such as the accelerometer, gyroscope and magnetometer.

In this embodiment, before collecting measurement data, it is necessary to initialize the configuration of sensors such as accelerometers, gyroscopes, and magnetometers, such as presetting the power parameters of the sensors, reset parameters, or the acquisition frequency of the sensors. Since the accelerometer, gyroscope and magnetometer in this embodiment are all connected on the I2C bus, therefore, the operation of the nine-axis measurement module 200 to read the measurement data shares an I2C interface with the initialization operation of the sensor, and the operation of reading the measurement data and sensor initialization operations need to be performed serially. As shown in FIG. 3 , the nine-axis measurement module 200 first writes corresponding initialization parameters into each sensor through the I2C bus to realize the initialization of each sensor, and then starts to read the measurement data of each sensor cyclically.

The attitude calculation module 300 is used to generate and output flight attitude data according to the nine-axis data transmitted by the nine-axis measurement module 200 using the navigation principle, and transmit the flight attitude data to the PID control module 400 . The flight attitude data here is used to record the state of the three-axis of the aircraft relative to a certain reference line, or a certain reference plane, or a certain fixed coordinate system in the air. The PID control module 400 is connected to the nine-axis measurement module 200 and the attitude calculation module 300, and includes at least three attitude angle control circuits arranged in parallel for the nine-axis data transmitted by the nine-axis measurement module 200 and the attitude calculation module 300. The flight attitude data is calculated to generate motor control data, and the motor control data is sent to the remote control servo module 500 . Wherein, each attitude angle control circuit controls an attitude angle correspondingly, and the attitude angle of the UAV includes a pitch angle, a roll angle, a yaw angle, and the like. At least three attitude angle control circuits work independently and in parallel to shorten the calculation time of the flight control circuit, and the accuracy of control data can be improved by adopting the parallel processing method of FPGA. The motor control data output by the PID control module 400 is used to control the operation of each motor, including throttle coefficient, pitch angle, roll angle, yaw angle and so on.

The remote control servo module 500 is used as the input and output execution equipment of the control signal of the drone, and is connected with the remote controller and the electronic governor connected with each motor of the drone, and the remote control servo module 500 controls each motor through the electronic governor running. Specifically, the remote control servo module 500 is connected to the receiver through an I/O interface, and the remote control is set correspondingly to the receiver. The operator encodes the control information through the remote controller and sends out the remote control signal in the form of electromagnetic waves. After the receiver demodulates the remote control signal, it transmits the demodulated remote control signal to the remote control servo module 500, and the remote control servo module 500 It is used to generate a control signal for controlling the electronic governor according to the received remote control signal and the motor control data output by the PID control module 400, and feed back the control signal to the PID control module 400 to control each motor of the drone in parallel running.

In one embodiment of the present invention, as shown in FIG. 2, the nine-axis measurement module 200 includes an interrupt control circuit 260 and a data buffer circuit 210, a data processing circuit 220, a data gating circuit 230, and a data restoration circuit 240 that are electrically connected in sequence. And the synchronous output circuit 250, the synchronous output module 250 is connected to the attitude calculation module 300, the synchronous output circuit 250 is used to synchronously generate nine-axis data, and the nine-axis data is sent to the attitude calculation module 300 for calculating the flight of the unmanned aerial vehicle pose data.

Wherein, the data buffer circuit 210 , the data processing circuit 220 and the synchronous output circuit 250 are connected to the controller module 100 , and the controller module 100 is used for gating the data processing circuit 220 and controlling the output of the synchronous output circuit 250 . The interrupt control circuit 260 is connected to the data gating circuit 230 and the data restoration circuit 240 , and the interrupt control circuit 260 is used to control the gating or closing of the data gating circuit 230 and the execution order of the data restoration circuit 240 through the output interrupt signal. In this embodiment, the data gating circuit 230 may be a data gating device.

The data buffer circuit 210 is connected with the three-axis accelerometer, the three-axis gyroscope and the three-axis magnetometer to read and store the measurement data of the three-axis accelerometer, the three-axis gyroscope and the three-axis magnetometer, and transfer the original data of the above-mentioned sensors to The measurement data is sent to the data processing circuit 220 . The data processing circuit 220 is used to perform operations such as filter processing and data calibration on the measurement data, and transmit the preprocessed measurement data to the data restoration circuit 240 through the data gating circuit 230 .

The data restoration circuit 240 is used to perform digital conversion and normalization processing on the measurement data, that is, to restore the actual value of the measurement data according to the AD conversion coefficient of each sensor, wherein the data restoration circuit 240 is a common circuit for nine-axis data, including The coefficient normalization unit 241 and the digital conversion unit 242 are electrically connected in sequence. In this embodiment, the serial execution sequence of the coefficient normalization unit 241 and the digital conversion unit 242 is controlled by the interrupt control circuit 260 . The coefficient normalization unit 241 can be used for normalization processing of measurement data, and the number system conversion unit 242 can be used for computer number system conversion.

Finally, the synchronous output circuit 250 waits for the nine-axis data (including the three-axis accelerometer measurement data, the three-axis gyroscope measurement data and the three-axis magnetometer measurement data) to be buffered once, according to the requirements of the attitude calculation module 300 for the nine-axis data. , pull up the indication signal, and output the nine-axis data to the attitude calculation module 300 .

Specifically, the data processing circuit 220 includes an accelerometer data processing unit, a gyroscope data processing unit and a magnetometer data processing unit arranged in parallel. Wherein, the accelerometer data processing unit includes a first smoothing filter bank 221 and a first data selector 222 electrically connected in sequence, for smoothing and filtering the measurement data of the accelerometer. The first data strobe 222 is connected to the controller module 100 and the data strobe circuit 300, and the controller module 100 is used to control the first data strobe to be turned on or off. When the controller module 100 sends a smoothness strobe signal to the first data strobe 222 according to the needs of the user, the three-axis measurement data output by the accelerometer is smoothed by the first smoothing filter bank 221, and then directly passed through the data strobe. The pass circuit 300 enters the data restoration circuit 240.

The gyroscope data processing unit includes a second smoothing filter bank 223, a zero bias calculation-elimination circuit and a second data gate 229 electrically connected in sequence, for smoothing and filtering the measured data of the gyroscope and eliminating the zero bias value processing. The second data gating unit 229 is connected to the controller module 100 and the data gating circuit 230 , and the controller module 100 is used to control the second data gating unit 229 to be turned on or off. Furthermore, in one embodiment, the zero bias value calculation-elimination circuit includes a zero bias value calculation unit 224 and a zero bias value elimination unit 225, and the second smoothing filter bank 223 is simultaneously connected to the zero bias value calculation unit 224 and the zero bias value calculation unit 224 Offset value elimination unit 225, and zero offset value calculation unit 224 is connected to zero offset value elimination unit 225, and the output of zero offset value elimination unit 225 is connected to the input of the second data gate 229 for eliminating the zero offset value of the gyroscope, Ensure the accuracy of flight control.

When the controller module 100 sends a smoothness gating signal to the second data gating device 229 according to the needs of the user, the three-axis measurement data of the gyroscope output by the gyroscope first passes through the smoothing filter of the second smoothing filter bank 223, and then enters The zero bias value calculation unit 224 calculates the zero bias value of the gyroscope, and then eliminates the zero bias value of the three-axis measurement data of the gyroscope through the zero bias value elimination unit 225 , and finally enters the data restoration circuit 240 through the data gating circuit 230 . Alternatively, the gyroscope three-axis measurement data output by the gyroscope is firstly smoothed by the second smoothing filter bank 223, and then the zero offset value of the gyroscope's three-axis measurement data is directly eliminated by the zero offset value elimination unit 225, and finally passed through the data The gating circuit 230 enters the data restoration circuit 240 .

The magnetometer data processing circuit includes a third smoothing filter bank 226 , a calibration-normalization circuit and a third data gate 201 electrically connected in sequence, for smoothing and calibrating the measurement data of the magnetometer. Wherein, the third data gating unit 201 is respectively connected to the controller module 100 and the data gating circuit 230 , and the controller module 100 is used for controlling the third data gating unit 201 to be turned on or off. Further, in one embodiment, the calibration-normalization circuit includes a data calibration unit 227 and a data normalization unit 228, and the third smoothing filter bank 226 is simultaneously connected to the data calibration unit 227 and the data normalization unit 228 , and the data calibration unit 227 is electrically connected to the data normalization unit 228, and the output of the data normalization unit 228 is connected to the input of the third data gate 201, which is used for the calibration of the three-axis measurement data of the magnetometer to ensure the flight control. precision.

That is, when the controller module 100 sends a smoothness gating signal to the third data gating device 201 according to the needs of the user, the three-axis measurement data of the magnetometer output by the magnetometer is firstly smoothed by the third smoothing filter bank 226, and then Enter the data calibration unit 227 for calibration, then normalize the coefficients of the three-axis measurement data of the magnetometer through the data normalization unit 228 , and finally enter the data restoration circuit 240 through the data gating circuit 230 . Or, after the three-axis measurement data of the magnetometer output by the magnetometer is smoothed and filtered by the third smoothing filter bank 226, the three-axis measurement data of the magnetometer is directly passed through the data normalization unit 228 for coefficient normalization, and finally passed Data gating circuit 230 enters data restoration circuit 240 .

In one embodiment of the present invention, as shown in FIG. 4 , the attitude calculation module 300 includes an accelerometer error measurement circuit 310, a magnetometer error measurement circuit 320, a gyroscope error measurement circuit 330, a quaternion update circuit 340, an attitude Transformation matrix update circuit 350 and attitude angle conversion circuit 360 . Wherein, the accelerometer error measurement circuit 310 and the magnetometer error measurement circuit 320 are all connected to the gyroscope error measurement circuit 330, and the gyroscope error measurement circuit 330 is electrically connected to the quaternion update circuit 340, the attitude conversion matrix update circuit 350 and the attitude angle in turn. The conversion circuit 360 and the attitude angle conversion circuit 360 are connected to the PID control module 400 for transmitting the flight attitude data of the drone to the PID control module 400 .

In the actual environment, the data output by the MEMS sensor usually has certain errors, so in order to ensure the accuracy of subsequent calculations, the measurement data output by the MEMS sensor should be processed by denoising and filtering to ensure the calculation accuracy of the system. In this embodiment, a complementary filtering algorithm is used to perform processing such as denoising filtering on the measurement data of each sensor. Wherein, the accelerometer error measurement circuit 310 is connected to the nine-axis measurement module 200, and is used to calculate the relative error between the accelerometer and the preset reference ratio according to the measurement data of the accelerometer in the nine-axis data, and generate an accelerometer error value. The magnetometer error measurement circuit 320 is connected to the nine-axis measurement module 200, and is used to calculate the relative error between it and the preset reference magnetic force according to the measurement data of the magnetometer in the nine-axis data, and generate a magnetometer error value.

The gyroscope error measurement circuit 300 is also connected to the nine-axis measurement module 200 for accelerometer error values generated by the accelerometer error measurement circuit 310, the magnetometer error values generated by the magnetometer error measurement circuit 320, and the gyroscope in the nine-axis data. The measurement data of the gyroscope is used to generate gyroscope correction data through a complementary filtering algorithm. The gyroscope error measurement circuit in this embodiment can be realized by using a complementary filter or the like. Since the gyroscope has a certain drift, the measured data will become more and more inaccurate. In this embodiment, the complementary filtering algorithm is used to refer to more measurement data of the gyroscope in a short period of time, and as time increases , the measurement data of the gyroscope is compensated and corrected by the measurement data of the accelerometer and the magnetometer. That is to say, due to the slow dynamic response of the accelerometer, there is an error in the high frequency band, which can be suppressed by a low-pass filter, and the gyroscope has a large error in the low frequency band due to the constant zero drift. , so a high-frequency filter is needed to suppress its low-frequency error, through the complementary characteristics of the complementary filter in its frequency domain, to suppress the interference error, to improve the accuracy of the measurement data, to meet the use requirements of the subsequent circuit, thereby improving the flight The control accuracy of the control circuit.

The quaternion update circuit 340 is used to generate a new quaternion value according to the gyroscope correction data and the last quaternion value. In this embodiment, the quaternion update circuit 340 uses a first-order Runge-Kutta algorithm (i.e. Pull algorithm) to update the quaternion, and output the new quaternion value of this update. It should be clear that a quaternion is a simple hypercomplex number. A quaternion is composed of a real number plus three complex numbers. It can be understood as a combination of a real number and a vector, or as a four-dimensional vector. Quaternion representations work best when it comes to combining rotations. Of course, in other embodiments, the attitude calculation module 300 may also express the rotation by means of matrix representation, Euler angle representation, or axis angle representation.

Attitude conversion matrix update circuit 350 is used to generate an attitude matrix according to the new quaternion value output by quaternion update circuit 340, and feeds back the new quaternion value to accelerometer error measurement circuit 310 and magnetometer error measurement circuit 320; attitude The angle conversion circuit 360 is used to generate the attitude angle according to the attitude matrix, and transmit the flight state data such as the attitude angle to the PID control module 400 .

In one embodiment of the present invention, as shown in Figure 5, the PID control module 400 includes an output control circuit 440 and three attitude angle control circuits arranged in parallel, each attitude angle control circuit correspondingly controls an attitude angle, three attitude angles The angle control circuit is divided into a pitch angle control circuit 410 electrically connected to the output control circuit 440, a roll angle control circuit 420 and a yaw angle control circuit 430, so that the attitude angle data output by the attitude calculation module 300 can be processed in parallel, Thereby shortening the operation time of the system and improving the operation efficiency.

The pitch angle control circuit 410, the roll angle control circuit 420 and the yaw angle control circuit 430 are respectively connected to the attitude calculation module 300 and the nine-axis measurement module 200, for obtaining the flight attitude data (that is, unmanned) that the attitude calculation module 300 outputs. Attitude angle data of the machine), nine-axis measurement data output by the nine-axis measurement module 200, external data such as remote control signals transmitted by the remote controller, and status signals of various sensors. The output control circuit 440 generates and outputs motor control data according to the signals transmitted by the three attitude angle control circuits, so as to separately control the operation of each motor through the electronic speed controller, and realize the parallel control of each motor. At the same time, the output control circuit 440 feeds back the motor control data to the pitch angle control circuit 410 , the roll angle control circuit 420 and the yaw angle control circuit 430 .

Specifically, the pitch angle control circuit 410, the roll angle control circuit 420, and the yaw angle control circuit 430 of this embodiment all adopt a double-loop structure, wherein the outer loop is used to control the angle, and the inner loop is used to control the angular velocity. The following describes the specific process of the PID control algorithm by taking the roll angle as an example in combination with Figure 6:

Outer loop control: lock the acquired gyroscope measurement data and the remote control signal of the remote control to ensure data accuracy and control precision, and combine the acquired gyroscope and remote control status signals to control the gyroscope measurement data and The remote control signal is pre-processed such as data filtering to reduce the interference of noise to the system. After that, perform PID operation (or PI operation and PD operation) on the preprocessed gyroscope measurement data and remote control signal, and generate and output the expected value of the inner loop PID control.

Inner loop control: Lock the acquired expected value of the inner loop PID control with the flight attitude data output by the attitude calculation module to ensure the accuracy of the data and control precision, and combine the status signal output by the outer loop control module and the attitude calculation The state signal output by the module performs preprocessing such as filtering on the expected value of the inner loop PID control and the flight attitude data to reduce the interference of noise on the system. Afterwards, perform PID operation (PI operation, PD operation) on the preprocessed flight attitude data and the expected value of the inner loop PID control, generate and output motor control data to control the roll angle of each motor. In addition, the PID control of the pitch angle and the yaw angle is basically the same as the control process of the roll angle, and will not be repeated here.

In one embodiment of the present invention, as shown in Figure 7, the remote control servo module 500 includes a receiving circuit 510, a motor control circuit 530, and a channel encoding circuit 520; the receiving circuit 510 is connected to the motor control circuit 530 and the channel encoding circuit 520, and the motor The control circuit 530 and the channel encoding circuit 520 are connected to the controller module 100, and the controller module 100 is used to control the initialization and running status of each module circuit.

Wherein, the receiving circuit 510 includes a receiving verification unit 511 and a preprocessing unit 512 that are electrically connected in sequence, wherein the receiving verification unit 511 is connected to the remote controller through an external receiver, and is used to receive the information sent by the remote controller that contains multiple channels. For the remote control signal of the data, the receiving verification unit 511 performs filter processing on the data of each channel of the received remote control signal, and then transmits the processed remote control signal to the preprocessing unit 512 . The preprocessing unit 512 is connected to the PID control module 400, and is used to perform operations such as linear constraint and format conversion on the filtered remote control signal according to the requirements of the PID algorithm for channel data, and then feed back the preprocessed remote control signal and other data to The PID control module 400 , that is, the preprocessing unit 512 is connected to the input end of the PID control module 400 .

In this embodiment, the remote controller inputs remote control signals with 7 channel data to the receiving circuit through the receiver, and correspondingly, the receiving verification unit is also provided with 7 verification channels, and filtering processing is performed on the data of the 7 channels respectively, so as to Improve the efficiency of data processing. Afterwards, the filtered remote control signal is sent to the general preprocessing unit 512 to complete the preliminary processing of the remote control signal. Finally, according to the function of each channel, adopt the corresponding processing mechanism. Among them, the data of the 7 channels of the remote control signal can be flight altitude, pitch angle, yaw angle, roll angle, flight speed, throttle coefficient, flight status and so on. For example:

One of the channel data of the remote control signal is used to control the pitch angle of the unmanned aerial vehicle, then filter processing is performed through the corresponding pitch angle verification channel in the receiving verification unit 511, and then the filtered pitch angle channel data is preprocessed After the unit is output to the input end of the pitch angle control circuit 410 of the PID control module 400, the pitch angle control circuit 410 performs the PID operation (PI/PD/PID calculation) according to the pitch angle channel data, the measurement data of the gyroscope and the measurement data of the accelerometer. ), output the motor control data used to control the pitch angle of the UAV.

The channel encoding circuit 520 is used as an encoding circuit for data such as remote control signals, and is used to generate control signals for UAV operating modes according to the remote control signals, and transmit the UAV operating mode signals to the controller module 100 to control the UAV to operate in different working mode. In this embodiment, the working modes of the drone include a debugging mode, a locking mode and a PID control mode.

In this embodiment, before the UAV starts to fly, it generally needs to perform operations such as throttle calibration or electrical programming on the remote control. When the system is powered on and started, the remote control must be locked to prevent accidental touch operations. When flying in the air, if you encounter an emergency, you must immediately lock the body and suspend the work of the UAV system to ensure the flight safety of the UAV. The channel coding circuit 520 is used to perform channel coding processing according to the received remote control signal according to the above different working modes, and send a corresponding working mode signal to the controller module, so that the UAV can fly or debug safely.

The motor control circuit 530 is connected to the PID control module 400, and the motor control circuit 530 generates the channel value of the motor according to the motor control data output by the PID control module 400 and the UAV operation mode signal output by the controller module 100, and converts the channel value of the motor It is the PWM control signal used to control the electronic governor. Specifically, the motor control circuit 530 includes a conversion unit 531 , a fifth data gate 532 and an electric regulation control unit 533 electrically connected in sequence. Wherein, the conversion unit 531 is connected to the PID control module 400, specifically, the conversion unit 531 is connected to the output terminal of the PID control module 400 (that is, the output control circuit 440), and is used to read the motor control data from the PID control module and convert the motor The control data is converted to the channel signal of the steering gear.

The input end of the fifth data strobe 532 is respectively connected to the conversion unit 531, the receiving verification unit 511 of the receiving circuit 510, and the controller module 100, and the output end of the fifth data strobe 532 is connected to the ESC control unit 533, The ESC control unit 533 is connected to the controller module 100 and the external ESC. The ESC control unit 533 is used to generate the channel value of the motor according to the channel signal of the steering gear and the UAV working mode signal transmitted by the controller module 100 and convert it into a PWM signal and output it to the electronic speed controller to control each motor running.

The following takes the quadrotor UAV as an example to illustrate the control principle of the motor control circuit:

The quadrotor UAV is a UAV driven by four motors fixed on the rigid cross structure. The movement of the UAV is controlled by controlling the speed difference of the four motors. According to the arrangement of the rotors, it can be divided into " X" mode and "+" mode.

If the quadrotor UAV is in "X" mode, the conversion relationship between the motor control data output by the PID control module 400 and the channel values of the four motors is:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\end{array}\right.$

Among them, M ₁ ~ M ₄ are used to represent the channel values of the four motors, Thr is used to represent the throttle coefficient, Ptich is used to represent the pitch angle, Roll is used to represent the roll angle, and Yaw is used to represent the yaw angle.

If the quadrotor UAV is in the "+" mode, the conversion relationship between the motor control data output by the PID control module 400 and the channel values of the four motors is:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\\ {\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; r</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Y</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; w</span>}\end{array}\right.$

Among them, M ₁ ~ M ₄ are used to represent the channel values of the four motors, Thr is used to represent the throttle coefficient, Ptich is used to represent the pitch angle, Roll is used to represent the roll angle, and Yaw is used to represent the yaw angle.

In one embodiment of the present invention, as shown in Figure 8, the barometer reading-compensation module 600 is connected through the barometer of the SPI interface peripheral, and the barometer is used to measure the atmospheric pressure of the environment altitude where the drone is located in real time, The atmospheric pressure measured by the barometer can be used to calculate the relative flight altitude of the UAV, so that the navigation data of the UAV can be corrected and the control accuracy of the UAV can be improved.

The barometer reading-compensation module 600 includes an initialization circuit 610, a data reading circuit 630, a fourth data strobe 620, a temperature compensation circuit 640, an AD coefficient normalization circuit 650, and a data reading circuit 610 electrically connected to the controller module 100, respectively. System conversion circuit 660. The fourth data strobe 620 is connected to the barometer, the initialization circuit 610 and the data reading circuit 630 are connected to the fourth data strobe 620, the data reading circuit 630, the temperature compensation circuit 640, the AD coefficient normalization circuit 650 and The digital conversion circuit 660 is electrically connected in turn, and the digital conversion circuit 660 is used to output the air pressure value and the temperature value.

After the system is reset, the controller module 100 first starts the initialization circuit 610, and the initialization circuit 610 sends a reset command and a barometer parameter reading command to the barometer through the SPI interface. When the initialization circuit 610 returns a completion signal to the controller module 100 , the controller module 100 controls the data reading circuit 630 to repeatedly read the pressure value and the temperature value of the barometer. The pressure value and temperature value read each time pass through the temperature compensation circuit 640 , the AD coefficient normalization circuit 650 and the digital system conversion circuit 660 in sequence, and then output.

The initialization and data reading process of the barometer reading-compensation module are described below in conjunction with Figure 9:

The initialization circuit 610 first sends a reset command (Reset command) to the barometer through the SPI interface, and after waiting for the first preset time (which can be 2.8ms), the initialization circuit 610 sends a barometer parameter reading command to the barometer through the SPI interface, Read the main parameters of the barometer. In this embodiment, the barometer mainly includes six parameters: pressure sensitivity, pressure offset, temperature and pressure sensitivity coefficient, pressure offset of temperature coefficient, reference temperature, sensitivity of temperature coefficient and so on. When the initialization circuit 610 completes the above operations, it returns a completion signal to the controller module 100 .

Then, the controller module 100 first sends the AD1 conversion command to the barometer, waits for a second preset time (may be 8.22ms), and then sends the ADC read command to control the data reading module 630 to read the barometric pressure value. The reading process of the temperature value is similar to the reading process of the air pressure value. The controller module 100 sends the AD2 conversion command to the barometer, waits for the second preset time (can be 8.22ms) and then sends the ADC reading command to control the data reading. Module 630 reads the temperature value. In this embodiment, the reading operation of the air pressure value and the reading operation of the temperature value are repeated alternately, so as to continuously read new air pressure values and temperature values to realize real-time control of the flying state of the drone.

Further, the barometer reading-compensation module 600 and the GPS module 700 are both connected to the data fusion module 800 , and the data fusion module 800 is electrically connected to the remote control servo module 500 and the attitude calculation module 300 . The GPS module 700 is used to obtain the positioning information of the drone, and the data fusion module 800 is used to read the air pressure value and the temperature value output by the compensation module 600 according to the barometer, the positioning information output by the GPS module 700 and the attitude calculation module 300 to generate Generate motor control data from the flight attitude data, and transmit the generated motor control data to the remote control servo module 500, so as to better control the operation of each motor and adjust the flight state of the drone.

The button module 900 is connected with the control button and the display lamp of the peripheral device, and is used for receiving the button signal input from the outside. The control button can be used to set the working mode of the flight control circuit, and the flight control circuit can also be reset by setting the reset button. The display light can be an LED display light, etc., used to indicate the working status of the drone. For example, a red light indicates that the drone is working in debugging mode, a yellow light indicates that the drone is working in lock mode, and a green light indicates that the drone is working in PID mode and so on.

In one embodiment of the present invention, the FPGA-based UAV flight control circuit communicates with the host computer 130 through the UART interface, and is used to transmit the control information and configuration information of the flight control circuit to the host computer.

The unmanned aerial vehicle flight control circuit based on FPGA of the present invention, by adopting FPGA as micro-controller, and is provided with the attitude solving module and obtains the flight attitude data of unmanned aerial vehicle in real time, and the PID control module is used for according to flight attitude data and nine axis The nine-axis data transmitted by the measurement module is calculated to generate motor control data, and the remote control servo module generates control signals according to the motor control data to realize parallel control of each motor of the drone. At the same time, because the parallel processing speed of FPGA is much higher than that of micro The serial processing speed of the controller, therefore, shortens the calculation time of the flight control circuit through the FPGA control platform, thereby improving the accuracy and real-time performance of the motor control, and laying the foundation for the generation of the UAV flight control chip.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (11)

1. A kind of FPGA-based unmanned aerial vehicle flight control circuit, it is characterized in that, comprises: controller module and nine-axis measurement module, attitude solving module, PID control module and remote control rudder electrically connected with said controller module respectively A machine module, wherein the nine-axis measurement module, the attitude calculation module, the PID control module and the remote control steering module are electrically connected in sequence; The nine-axis measurement module is connected to an accelerometer, a gyroscope, and a magnetometer, and is used to generate and output nine-axis data according to measurement data transmitted by the accelerometer, the gyroscope, and the magnetometer; The attitude calculation module is used to generate and output flight attitude data according to the nine-axis data; The PID control module is connected to the nine-axis measurement module, and the PID control module includes at least three attitude angle control circuits arranged in parallel for transmitting the nine-axis data and the flight attitude data according to the nine-axis measurement module. Calculate and generate motor control data; The remote control servo module is connected to the remote control receiver and the electronic governor connected to each motor of the drone, and the remote control servo module is used to control the The motor control data output by the module generates a control signal for controlling the electronic governor, and feeds back the control signal to the PID control module to control the operation of each motor of the drone in parallel. 2. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 1, is characterized in that, described nine-axis measurement module comprises interruption control circuit and data buffer circuit, data processing circuit, data gating circuit that are electrically connected in sequence , data restoration circuit and synchronous output circuit; Wherein, the data buffer circuit, the data processing circuit and the synchronous output module are connected to the controller module; the interrupt control circuit is connected to the data gating circuit and the data restoration circuit, and is used to control the Turn on or off of the data strobe circuit; The data buffer circuit is connected to the accelerometer, the gyroscope and the magnetometer to obtain the measurement data of the accelerometer, the gyroscope and the magnetometer, and the data processing circuit is used for The measurement data is filtered, the data restoration circuit is used to perform digital conversion and normalization processing on the measurement data, the synchronization output module is connected to the attitude calculation module, and the synchronization output circuit is used for Synchronously generate the nine-axis data, and transmit the nine-axis data to the attitude calculation module. 3. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 2, is characterized in that, described data processing circuit comprises accelerometer data processing unit, gyroscope data processing unit and magnetometer data processing unit; The accelerometer data processing unit includes a first smoothing filter bank and a first data gate electrically connected in sequence, for smoothing and filtering the measurement data of the accelerometer; The gyroscope data processing unit includes a second smoothing filter bank, a zero bias value calculation-elimination circuit and a second data gate, which are electrically connected in sequence, for smoothing and filtering the measured data of the gyroscope, eliminating zero Handling of partial values; The magnetometer data processing circuit includes a third smoothing filter bank, a calibration-normalization circuit and a third data gate that are electrically connected in sequence, and are used to smooth filter and calibrate the measurement data of the magnetometer; Wherein, the first data strobe, the second data strobe and the third data strobe are respectively connected to the controller module. 4. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 1, is characterized in that, described attitude calculation module comprises accelerometer error measurement circuit, magnetometer error measurement circuit, gyroscope error measurement circuit, quadruple Number update circuit, attitude conversion matrix update circuit and attitude angle conversion circuit; Both the accelerometer error measurement circuit and the magnetometer error measurement circuit are connected to the gyroscope error measurement circuit, and the gyroscope error measurement circuit is electrically connected to the quaternion update circuit and the attitude conversion matrix update circuit in turn. circuit and the attitude angle conversion circuit; The gyroscope error measurement circuit is used to generate the accelerometer error value generated by the accelerometer error measurement circuit, the magnetometer error value generated by the magnetometer error measurement circuit, and the measurement data of the gyroscope through a complementary filtering algorithm Gyroscope correction data; The quaternion update circuit is used to generate a new quaternion value according to the gyroscope correction data and the last quaternion value; the attitude transformation matrix update circuit is used to generate an attitude matrix according to the new quaternion value , and feed back the new quaternion value to the accelerometer error measurement circuit and the magnetometer error measurement circuit; the attitude angle conversion circuit is used to generate an attitude angle according to the attitude matrix. 5. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 1, is characterized in that, described PID control module comprises output control circuit and three described attitude angle control circuits that are arranged in parallel, three described attitudes The angle control circuits are respectively a pitch angle control circuit, a roll angle control circuit and a yaw angle control circuit; The pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit are respectively connected to the attitude calculation module, the nine-axis measurement module and the output control circuit; the output control circuit outputs the The motor control data is fed back to the pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit. 6. The FPGA-based UAV flight control circuit according to claim 5, wherein the pitch angle control circuit, the roll angle control circuit and the yaw angle control circuit all adopt a double-loop structure. 7. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 1, is characterized in that, described remote steering gear module comprises receiving circuit, motor control circuit and channel encoding circuit; Described receiving circuit connects described motor control circuit and the channel encoding circuit, the motor control circuit and the channel encoding circuit are connected to the controller module; The receiving circuit is connected to the remote controller receiver, and is used for receiving the remote control signal sent by the remote controller and including multiple channel data, and respectively processing the multiple channel data of the remote control signal; the channel encoding circuit is used for Generate a control signal for the UAV working mode according to the remote control signal, and transmit the UAV working mode signal to the controller module; The motor control circuit is connected to the PID control module, and the motor control circuit generates the channel value of the motor according to the motor control data output by the PID control module and the UAV working mode signal, and sends the motor The numerical value of the channel is converted into a control signal for controlling the electronic governor. 8. The FPGA-based UAV flight control circuit according to any one of claims 1-7, further comprising a barometer reading-compensation module connected with the barometer; The barometer reading-compensation module includes an initialization circuit, a data reading circuit, a fourth data strobe, a temperature compensation circuit, an AD coefficient normalization circuit and a digital conversion circuit electrically connected to the controller module respectively ; The fourth data strobe is connected to the barometer, the initialization circuit and the data reading circuit are connected to the fourth data strobe, the data reading circuit, the temperature compensation circuit, The AD coefficient normalization circuit and the digital system conversion circuit are electrically connected in sequence, and the digital system conversion circuit is used to output air pressure value and temperature value. 9. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 8, is characterized in that, also comprises GPS module and data fusion module; The barometer reading-compensation module and the GPS module are all connected to the data fusion module, and the data fusion module is electrically connected to the remote steering gear module and the attitude calculation module; The GPS module is used to obtain the positioning information of the drone, and the data fusion module is used to read the air pressure value, the temperature value output by the compensation module according to the barometer, the positioning information output by the GPS module, and The flight attitude data generated by the attitude calculation module generates the motor control data. 10. the unmanned aerial vehicle flight control circuit based on FPGA according to claim 8, is characterized in that, also comprises the timer module that is electrically connected with described controller module, reset module and button module; The button module is connected with the control buttons and display lights of the peripherals, and the display lights are used to indicate the working status of the drone. 11. FPGA-based UAV flight control circuit according to claim 8, is characterized in that, described FPGA-based UAV flight control circuit is connected with host computer communication.