CN114527698B - A redundant flight controller - Google Patents

Abstract

The invention discloses a redundant flight controller, which solves the problem of safety redundancy of an unmanned aerial vehicle flight controller and improves the performance of stable operation of the flight controller in a complex environment. A redundant flight controller comprises a first central processing unit, a second central processing unit, a heartbeat monitoring module, a first IMU sensor, a second IMU sensor, a change-over switch and a power module; the first central processing unit continuously reads the data of the first IMU sensor, and when the data read by the first central processing unit is normal, the first central processing unit sends a first heartbeat signal to the heartbeat monitoring module, and otherwise, the first heartbeat signal is stopped being sent; the second CPU is the same as the first CPU; the heartbeat monitoring module selects the first central processor or the second central processor to output PWM signals through the change-over switch according to the heartbeat signals. The purpose that the central processing unit and the IMU sensor fail and the flight controller can continue to stably run is achieved.

Description

A redundant flight controller

Technical field

The invention relates to the field of multi-rotor aircraft, and in particular to a redundant flight controller.

Background technique

Rotary-wing aircraft have relatively efficient low-altitude flight capabilities and have been widely used in aerial photography, logistics, agriculture and other fields. The flight controller is the core control component of the aircraft. Its task is to receive data from internal sensors (gyroscope, accelerometer, magnetometer, barometer, etc.) and external sensors (GPS positioning, external magnetometer, etc.) through the central processor. The control algorithm is converted into the control signal of the electronic speed controller, thereby controlling the attitude, position and height of the aircraft. The above-mentioned flight controllers are usually used in small aircraft such as drones, while medium and large aircraft and manned aircraft require a higher level of safety and require flight controllers to have stable operation performance in complex environments. Existing flight controllers use an architecture based on a microcontroller plus multiple sensors, which has poor reliability and stability. When there is a problem with the microcontroller or a sensor fails, the aircraft will be at risk.

The patent number CN201621454735.2 provides a multi-rotor drone flight controller to improve the flight controller's computing processing capabilities, peripheral expansion capabilities, earthquake resistance and stability, including: flight control motherboard , flexible sensor board, interface board and shock absorption device. The flight control motherboard is provided with a master Cortex-M4 microcontroller and a slave Cortex-M3 microcontroller. The flexible sensor board is provided with two sets of gyroscopes and acceleration sensors. meter and geomagnetic sensor, the interface board includes a left interface and a right interface, and the shock absorbing device is a gel pad. This solution will only use the Cortex-M3 microcontroller as an interface extension and sensor margin. It does not have the ability to independently control the aircraft, so there is no safety margin for the flight controller.

Contents of the invention

The purpose of the present invention is to provide a redundant flight controller in view of the shortcomings of the existing technology.

The object of the present invention is achieved through the following technical solutions: a redundant flight controller, including a first central processor, a second central processor, a heartbeat monitoring module, a first IMU sensor, a second IMU sensor, a switching Switch and power module; the first central processor continuously reads the data of the first IMU sensor. When the data read by the first central processor is normal, it sends the first heartbeat signal to the heartbeat monitoring module, otherwise it stops sending. The first heartbeat signal; the second central processor continuously reads the data of the second IMU sensor. When the data read by the second central processor is normal, it sends the second heartbeat signal to the heartbeat monitoring module, otherwise it stops sending. a second heartbeat signal; the first central processor and the second central processor work independently and output PWM signals to the switch respectively;

The heartbeat monitoring module uses the following method to select the first central processor or the second central processor to output the PWM signal through the switch:

a) When the heartbeat monitoring module can receive the first heartbeat signal normally, the heartbeat monitoring module sends a command to the switch, and the switch selects to output the PWM signal of the first central processor;

b) When the heartbeat monitoring module cannot receive the first heartbeat signal but can receive the second heartbeat signal normally, the heartbeat monitoring module sends a command to the switch, and the switch selects to output the PWM signal of the second central processor;

c) When the heartbeat monitoring module cannot receive the first heartbeat signal and the second heartbeat signal, the heartbeat monitoring module can independently control the emergency landing of the aircraft;

The power module supplies power to all other devices.

Further, the power module includes a battery, a first step-down DCDC, a second step-down DCDC, a power management chip, a first LDO and a second LDO; the battery inputs the first step-down DCDC and the second step-down DCDC in parallel. , generate two 5V voltages and input them into the power management chip; the power management chip controls the stability of the power supply of the first LDO and the second LDO; the first LDO and the second LDO output voltages respectively to power all other devices.

Further, the first heartbeat signal and the second heartbeat signal may be a pulse or other forms of signals.

Further, the frequency of the first heartbeat signal and the second heartbeat signal is greater than 100 Hz.

Further, the heartbeat monitoring module may be a dedicated chip or a programmable logic device that processes the information of the heartbeat signal in parallel.

Further, other sensors and other peripheral devices are also included, and the first central processor and the second central processor continuously read data of other sensors and other peripheral devices respectively.

Further, the first central processor, the first IMU sensor, the heartbeat monitoring module, the switch and the power module are respectively arranged on the front of the PCB board; the second central processor, the second IMU sensor, other sensors and other The peripherals are arranged on the back side of the PCB board.

The beneficial effects of the present invention are:

1. Adopt a redundant flight controller of the present invention and use the architecture of two central processors. The two central processors are equal to each other and serve as backups for each other, which maximizes the safety and stability of the flight controller;

2. Adopt a redundant flight controller of the present invention and use the heartbeat monitoring module to receive the status data of the central processor and each sensor in real time. When an abnormal state is detected, it can seamlessly switch to another central processor and sensor in real time. The sensor is very effective in improving the safety and stability of the flight controller;

3. Adopt a redundant flight controller of the present invention, using a configuration of two step-down DCDC chips and a power management chip. The two 5V voltages will back up each other and switch seamlessly; maximizing the efficiency of the power supply. safety and stability;

4. Using a redundant flight controller of the present invention, the first central processor and the second central processor and corresponding sensors are respectively arranged on the front and back sides of the hardware PCB, which maximizes the visibility of the aircraft status and The accuracy of flight attitude sampling is improved; at the same time, the safety and stability of the flight controller are improved in terms of hardware structure.

Description of the drawings

Figure 1 is a schematic diagram of the overall system architecture of a redundant flight controller according to Embodiment 1 of the present invention;

Figure 2 is a power schematic diagram of a redundant flight controller according to Embodiment 1 of the present invention;

Figure 3 is a schematic diagram of the overall system architecture of Embodiment 2 of a redundant flight controller of the present invention;

Figure 4 is a schematic PCB layout diagram of a redundant flight controller according to Embodiment 2 of the present invention;

Figure 5 is a system flow chart of Embodiment 2 of a redundant flight controller according to the present invention;

In the figure, 1-first central processor, 2-second central processor, 3-first IMU sensor, 4-second IMU sensor, 5-heartbeat monitoring module, 6-switch, 7-other sensors, 8 -Other peripherals, 9-electronic speed regulator, 10-battery, 11-first step-down DCDC, 12-second step-down DCDC, 13-power management chip, 14-first LDO, 15-second LDO, 16-Power module.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described here are only used to explain the present invention and are not exhaustive. Example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts are within the protection scope of the present invention.

Example 1

A redundant flight controller as shown in Figure 1 includes a first central processor 1, a second central processor 2, a heartbeat monitoring module 5, a first IMU sensor 3, a second IMU sensor 4, and a switch 6 and power module 16; the first central processor 1 communicates with the first IMU sensor 3, and the first central processor 1 constantly reads the data of the first IMU sensor 3, and the data of the first IMU sensor 3 includes The attitude data of the aircraft, when the data read by the first central processor 1 is normal, the first heartbeat signal is sent to the heartbeat monitoring module 5, and if the data read by the first central processor 1 is abnormal, it stops sending the first heartbeat signal to the heartbeat monitoring module 5. A heartbeat signal; the second central processor 2 communicates with the second IMU sensor 4, and the second central processor 2 continuously reads the data of the second IMU sensor 4, and the data of the second IMU sensor 4 includes the aircraft If the data read by the second central processor 3 is normal, it will send the second heartbeat signal to the heartbeat monitoring module 5. If the data read by the second central processor 2 is abnormal, it will stop sending the second heartbeat signal to the heartbeat monitoring module 5. Heartbeat signal; the first IMU sensor 3 and the second IMU sensor 4 are independent of each other and sense the attitude of the aircraft respectively; the first central processor 1 and the second central processor 2 work independently and output PWM signals to the switch 6 respectively;

The heartbeat monitoring module 5 uses the following method to select the first central processor 1 or the second central processor 2 to output the PWM signal through the switch 6:

a) When the heartbeat monitoring module 5 can receive the first heartbeat signal normally, the heartbeat monitoring module 5 sends a command to the switch 6, and the switch 6 selects to output the PWM signal of the first central processor 1;

b) When the heartbeat monitoring module 5 cannot receive the first heartbeat signal but can receive the second heartbeat signal normally, the heartbeat monitoring module 5 sends a command to the switch 6, and the switch 6 selects and outputs the signal of the second central processor 2. PWM signal;

c) When the heartbeat monitoring module 5 cannot receive the first heartbeat signal and the second heartbeat signal, the heartbeat monitoring module 5 can independently control the emergency landing of the aircraft;

The power module 16 supplies power to all other devices.

The heartbeat monitoring module 5 may be a dedicated chip or a programmable logic device, and processes the information of the heartbeat signal in parallel.

The working process of a redundant flight controller is as follows:

The first central processor 1 communicates with the first IMU sensor 3. When the first central processor 1 can receive the data of the first IMU sensor 3 normally, the first central processor 1 sends a message to the heartbeat monitoring module every once in a while (millisecond level). 5. Send the first heartbeat signal, otherwise stop sending the first heartbeat signal; similarly, the second central processor 2 communicates with the second IMU sensor 4. When the second central processor 2 can normally receive the second IMU sensor 4 data, the second central processor 2 sends the second heartbeat signal to the heartbeat monitoring module 5 at intervals (millisecond level), and otherwise stops sending the second heartbeat signal; the first central processor 1 and the second central processor 2 The two work independently and output PWM signals to switch 6 respectively;

The heartbeat signal may be a pulse or other form of signal;

When both the first central processor 1 and the second central processor 2 send heartbeat signals to the heartbeat monitoring module 5 normally, the heartbeat monitoring module 5 sends a switching command to the switch 6, and the switch 6 defaults to the output of the first central processor 1. PWM signal;

When the first central processor 1 stops sending the first heartbeat signal to the heartbeat monitoring module 5 and the second central processor 2 normally sends the second heartbeat signal to the heartbeat monitoring module 5, the heartbeat monitoring module 5 sends a switching command to the switch 6, The switch 6 selects the PWM signal output by the second central processor 2;

When the second central processor 2 stops sending the second heartbeat signal to the heartbeat monitoring module 5 and the first central processor 1 normally sends the first heartbeat signal to the heartbeat monitoring module 5, the heartbeat monitoring module 5 sends a switching command to the switch 6, The switch 6 selects the PWM signal output by the first central processor 1;

The output PWM signal is input to the electronic speed controller in the aircraft to control the operation of the aircraft's motor so that the aircraft can fly normally;

When both the first central processor 1 and the second central processor 2 stop sending heartbeat signals to the heartbeat monitoring module 5, the heartbeat monitoring module 5 can independently control the emergency landing of the aircraft.

The frequency of the heartbeat signal sent by the first central processor 1 or the second central processor 2 to the heartbeat monitoring module 5 is greater than 100 Hz, which means that the heartbeat monitoring module 5 can process the first central processor 1 or the second central processor within 10 milliseconds. 2; when the heartbeat monitoring module 5 detects an abnormality in the heartbeat signal, the aircraft is out of control within 10 milliseconds. At this time, the heartbeat monitoring module 5 in the redundant flight controller outputs a switching command or performs an emergency landing. can control the aircraft back to normal state.

Figure 2 is a schematic structural diagram of the power module 16 in a redundant flight controller. The power module 16 includes a battery 10, a first step-down DCDC 11, a second step-down DCDC 12, a power management chip 13, a first LDO 14 and The second LDO 15; the battery 10 inputs the first step-down DCDC 11 and the second step-down DCDC 12 in parallel to generate two 5V voltages and input them into the power management chip 13; the power management chip 13 is responsible for managing the two 5V voltages. When one of the 5V voltages fails, it can quickly and seamlessly switch to the other 5V voltage to ensure the stability of the power supply to the first LDO 14 and the second LDO 15; the first LDO 14 and the second LDO 15 output 3.3V and 1.8V respectively. voltage to power all other devices; the two 5V voltages will back up each other and switch seamlessly; maximizing the safety and stability of the power supply.

Example 2

As shown in Figure 3, the present invention also provides a schematic structural diagram of a redundant flight controller. The redundant flight controller also includes other sensors 7 and other peripherals 8. The other sensors 7 and other peripherals 8 are respectively Communicates with the first central processor 1 and the second central processor 2; the first central processor 1 and the second central processor 2 continuously read data from other sensors 7 and other peripherals (8) respectively.

The other sensors 7 include a barometer, electronic compass, GPS, etc., and the other peripherals 8 include a data transmission module, a remote control receiver, etc.

As shown in Figure 4, a redundant flight controller PCB layout diagram, the first central processor 1, the first IMU sensor 3, the heartbeat monitoring module 5, the switch 6 and the power module 16 are respectively laid out on the front of the PCB board. (TOP side); the second central processor 2, the second IMU sensor 4, other sensors 7 and other peripherals 8 are respectively arranged on the back side of the PCB board (BOTTOM side); connect the first central processor 1 and the second The central processor 2 and other components are arranged on the front and back sides of the hardware PCB, which maximizes the accuracy of sampling the aircraft status and flight attitude; at the same time, the safety and stability of the flight controller are improved in terms of hardware structure.

As shown in Figure 5, it is an application case of Embodiment 2, further describing the functions of the first central processor 1, the second central processor 2 and the heartbeat monitoring module 5; after the system is powered on and runs, the first central processor 1 and the second central processor 2 continuously read the data of the first IMU sensor 3 or the second IMU sensor 4 as well as other sensors 7 and other peripherals 8 respectively; if the data is normal, the first central processor 1 will time (millisecond level) to send the first heartbeat signal to the heartbeat monitoring module 5. If the data is abnormal, the first central processor 1 stops sending the first heartbeat signal to the heartbeat monitoring module 5; similarly, if the data is normal, the second central processor 1 2. Send the first heartbeat signal to the heartbeat monitoring module 5 at regular intervals (millisecond level). If the data is abnormal, the second central processor 2 stops sending the second heartbeat signal to the heartbeat monitoring module 5; when the heartbeat monitoring module 5 can After receiving the second heartbeat signal normally, the heartbeat monitoring module 5 sends a command to the switch 6, and the switch 6 selects to output the PWM signal of the first central processor 1; when the heartbeat monitoring module 5 cannot receive the first heartbeat signal, it If the second heartbeat signal can be received normally, the heartbeat monitoring module 5 sends a command to the switch 6, and the switch 6 selects to output the PWM signal of the second central processor 2; when the heartbeat monitoring module 5 cannot receive the first heartbeat signal and If there is a second heartbeat signal, an emergency landing will be performed; when the system is powered on and running, the heartbeat monitoring module 5 will continuously detect the heartbeat signal.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (7)

1. The redundant flight controller is characterized by comprising a first central processing unit (1), a second central processing unit (2), a heartbeat monitoring module (5), a first IMU sensor (3), a second IMU sensor (4), a change-over switch (6) and a power supply module (16); the first central processing unit (1) continuously reads the data of the first IMU sensor (3), and when the data read by the first central processing unit (1) are normal, the first central processing unit sends a first heartbeat signal to the heartbeat monitoring module (5), and otherwise, the first heartbeat signal is stopped from being sent; the second central processing unit (2) continuously reads the data of the second IMU sensor (4), and when the data read by the second central processing unit (2) are normal, the second central processing unit sends a second heartbeat signal to the heartbeat monitoring module (5), and otherwise, the second central processing unit stops sending the second heartbeat signal; the first central processing unit (1) and the second central processing unit (2) work independently and respectively output PWM signals to the change-over switch (6);

the heartbeat monitoring module (5) selects the first central processing unit (1) or the second central processing unit (2) to output PWM signals through the change-over switch (6) in the following way:

a) When the heartbeat monitoring module (5) can normally receive the first heartbeat signal, the heartbeat monitoring module (5) sends a command to the change-over switch (6), and the change-over switch (6) selects and outputs the PWM signal of the first central processing unit (1);

b) When the heartbeat monitoring module (5) cannot receive the first heartbeat signal but can normally receive the second heartbeat signal, the heartbeat monitoring module (5) sends a command to the change-over switch (6), and the change-over switch (6) selects and outputs the PWM signal of the second central processing unit (2);

c) When the heartbeat monitoring module (5) cannot receive the first heartbeat signal and the second heartbeat signal, the heartbeat monitoring module (5) can independently control the aircraft to fall in an emergency;

the power module (16) provides power to all other devices.

2. The redundant flight controller of claim 1, wherein the power module (16) comprises a battery (10), a first buck DCDC (11), a second buck DCDC (12), a power management chip (13), a first LDO (14), and a second LDO (15); the battery (10) is input into a first step-down DCDC (11) and a second step-down DCDC (12) in parallel, generates two paths of 5V voltages and inputs the two paths of 5V voltages into the power management chip (13); the power management chip (13) controls the stability of power supply of the first LDO (14) and the second LDO (15); the first LDO (14) and the second LDO (15) respectively output voltages to supply power for all other devices.

3. A redundant flight controller according to claim 1 wherein the first and second heartbeat signals are pulses or other forms of signals.

4. The redundant flight controller of claim 1, wherein the first and second heartbeat signals have a frequency greater than 100 hertz.

5. A redundant flight controller according to claim 1, characterized in that the heartbeat monitoring module (5) may be a dedicated chip or a programmable logic device, processing the information of the heartbeat signal in parallel.

6. A redundant flight controller according to claim 2, further comprising other sensors (7) and other peripherals (8), the first central processor (1) and the second central processor (2) constantly reading data from the other sensors (7) and other peripherals (8), respectively.

7. The redundant flight controller of claim 6, wherein the first central processing unit (1), the first IMU sensor (3), the heartbeat monitoring module (5), the change-over switch (6) and the power supply module (16) are respectively arranged on the front surface of the PCB board; the second central processing unit (2), the second IMU sensor (4), other sensors (7) and other peripherals (8) are respectively distributed on the back surface of the PCB.