RU2845342C1 - General purpose flight controller for a multi-rotor unmanned aerial vehicle - Google Patents

Abstract

FIELD: aviation.

SUBSTANCE: invention relates to the unmanned aerial vehicles information-measuring and control systems. Controller comprises: power supply module, computer module and connected to it screen menu module and video transmitter interface connected to it, servo drives control module, supply voltage monitoring module with protection against incorrect power-up and electronic speed controller interface, switches control module, sound radiator interface, optoelectronic equipment selection module , connected radio channel receiver interface and SBUS inverter, asynchronous interfaces module, navigation and orientation system module, memory module and USB connector.

EFFECT: broader functional capabilities of information-measurement and control systems due to controlled switches for connecting external peripheral devices.

5 cl, 2 dwg

Description

The invention relates to information-measuring and control systems of unmanned aerial vehicles (UAVs) and can be used for automatic control of small-sized UAVs with vertical takeoff and landing, primarily of the multi-rotor type.

The flight of any UAV consists of three stages: takeoff, cruising flight, landing. Cruising flight is performed under the control of a flight controller, which actually acts as an autopilot. The number of flight controller functions depends on the availability of appropriate peripherals and additional devices on board the UAV. The flight controller functions include:

- stabilization and orientation of UAVs in the air;

- maintaining altitude (using a barometer) and position (using GPS or optical-electronic means (OEM) using special confidence markers);

- automatic flight to pre-set points (optional);

- transmission of current flight parameters to the ground using a modem or Bluetooth (optional);

- ensuring flight safety (return to the take-off point in case of loss of control signal, automatic landing);

- connection of additional peripherals: OSD, LED indication, etc.

Navigation support for the flight controller is often provided by GPS/GLONASS satellite positioning systems. The typical accuracy of modern GPS/GLONASS receivers in the horizontal plane with good satellite visibility (clear field) and the use of correction algorithms is from 1 to 30 meters.

A typical example of a UAV flight controller is the ArduPilot Mega (ARM) 2.8 [https://chipster.ru/catalog/robotech/drones/flight-controllers/5170.html]. This is a compatible flight controller developed by the DIY Drones community. It is capable of controlling autonomous multi-rotor vehicles, traditional helicopters, and ground-based wheeled robots. This controller uses ArduРilot as its onboard software.

The disadvantage of this device is the lack of a clearly expressed modular architecture and process interaction scheme. As a result, the complexity of modifying the source code and customizing it to solve a new practical problem increases significantly.

Also known is the CC3D flight controller [https://multicopterwiki.ru/index.php/CopterControl3D], which has a 32-bit STM32F405RGT6 ARM Cortex M4 processor with a clock frequency of 168 MHz, 1 MB of flash memory and runs the FreeRTOS operating system and LibrePilot software. This software is an open source project based on OpenPilot and implements the functions of a flight controller for a quadcopter.

Also known are the MambaF405 MK2, MATEKSYS F405-miniTE devices – flight controllers with a 32-bit STM32F405RGT6 ARM Cortex M4 processor with a clock frequency of 168 MHz. These controllers use Betaflight, Inav and Ardupilot as onboard software.

The disadvantage of these systems is the impossibility of precise navigation and reconnaissance due to the lack of a magnetic field sensor and the ability to connect more than one OES. In addition, a backup system for managing the functions of the device using controlled switches is not implemented.

The closest analogue to the claimed invention is the flight control system described in the RU patent for utility model No. 164139. The system consists of a low-level control module containing a low-level control module controller based on a 32-bit microprocessor, a neural network chip, a COM port, interfaces for connecting motion control devices, interfaces for connecting external sensors, a GNSS receiver, a power supply connector, a power supply monitoring module, four baroaltimeters, four magnetometers, four accelerometers, four gyroscopes, four thermometers, and a high-level control module containing a high-level control module controller based on a multi-core 32-bit microprocessor combined with a graphics processor, a video input, two USB ports, a Wi-Fi module and a data storage device. The inputs of the neural network chip, COM port, motion control device connection interfaces, and external sensor connection interfaces are connected to the outputs of the low-level control module controller. The outputs of the power supply monitoring module, neural network chip, COM port, motion control device connection interfaces, external sensor connection interfaces, GNSS receiver, each baroaltimeter, each magnetometer, each accelerometer, each gyroscope, each thermometer are connected to the inputs of the low-level control module controller. The video input, the outputs of the graphics processor, each USB port, Wi-Fi module, and data storage device are connected to the inputs of the high-level control module controller. The inputs of the graphics processor, each USB port, Wi-Fi module, and data storage device are connected to the outputs of the high-level control module controller. The inputs of the low-level control module controller are connected to the outputs of the high-level control module controller. The outputs of the high-level control controller are connected to the inputs of the low-level control module controller. The high-level control module is powered from the low-level control module.

The disadvantage of the closest analogue is the failure to realize the full potential of the Raspberry Pi single-board computer processor, which has the interfaces required for UAVs and unused components, and also requires additional connection of the main sensors of the stabilization system, orientation, navigation and the memory module. This fact determines the non-compact dimensions of the device, as well as its significant cost price.

The objective of the claimed invention is to ensure autonomous flight of a multi-rotor UAV without connecting a global satellite navigation module, including in harsh climatic conditions, with an increase in visibility for the operator with the possibility of expanding the functionality of information-measuring and control systems, including using artificial intelligence technologies.

The essence of the claimed technical solution is that the general-purpose flight controller for a multirotor UAV is made on the basis of a printed circuit board containing the following located on it: a power supply module with the ability to convert the input voltage into a voltage of 5V, 3.3V and 9V, a computing module and connected to it - an on-screen menu module and a video transmitter interface connected to it, a servo drive control module, a supply voltage monitoring module with protection against incorrect power supply and an electronic speed controller interface, a switch control module, an audio emitter interface, an OES selection module, a connected radio channel receiver interface and an SBUS inverter, an asynchronous interface module, a navigation and orientation system module, a memory module and a USB connector, wherein two OES interfaces are organized for working with the OES selection module, connected to the on-screen menu module via the video transmitter interface, the electronic speed controller interface module is connected directly to the computing module.

An invention is also claimed in which, along with the above-described features, the navigation and orientation system module includes a barometric altimeter, a three-axis angular velocity sensor, a three-axis linear acceleration sensor, and a three-axis magnetic field sensor.

In addition, in the claimed technical solution, the interface for connecting video transmitters is designed with the ability to connect digital and analog video transmitters.

A flight controller is also declared, in which, along with the above-described features, the radio channel receiver interface and SBUS inverter are connected in series or in parallel.

The technical result of the claimed invention is as follows.

The flight controller combines a number of solutions that allow to significantly increase the performance of the control system due to the design of the product based on a modular form with a connection between the components via an asynchronous interface. The proposed design of the flight controller allows to connect up to six expansion modules of various purposes for unification in the control system via an asynchronous interface with the provision of the function of autonomous and automatic flights. In the claimed device, a full-fledged inertial navigation system is formed without connecting external periphery due to the presence of the necessary sensors in the flight controller, which ensures an increase in the reliability of the UAV control system.

A distinctive feature of the flight controller is the presence of controlled switches for turning on external peripheral devices.

In addition, the claimed technical solution implements the possibility of increasing the visibility of the UAV by organizing the connection of two OES, using a gimbal suspension, or without using it, which is especially important for UAVs that do not have a variable field of view in flight, which allows increasing the reliability and safety of the flight, takeoff and landing.

The claimed invention is explained with the help of Fig. 1-2, which show:

Fig. 1 - structural diagram of a general-purpose flight controller for a multi-rotor unmanned aerial vehicle;

Fig. 2 - general view of an example of the invention, under the letter a) - top view, under the letter b) - bottom view.

The general-purpose flight controller for a multirotor unmanned aerial vehicle is based on a printed circuit board. The latter contains a power supply module, a computer module, an on-screen menu module, a video transmitter interface, a servo drive control module, a supply voltage monitoring module, a switch control module, an audio emitter interface, a controller operation indicator LED module, a UES selection module, two UES interfaces, a radio channel receiver interface, an SBUS inverter, an asynchronous interface module, a navigation and orientation system module, a memory module, and a USB connector. The UES interfaces are designed to work with the UES selection module and are connected to the on-screen menu module. One of the UES interfaces is additionally connected to the computer. The power supply module is configured to convert the input voltage to 5V, 3.3V, and 9V. The on-screen menu module is connected to the video transmitter interface and the computer module. The supply voltage monitoring module implements protection against incorrect power supply and an electronic speed controller interface. The radio channel receiver interface and the SBUS inverter are connected to each other. The navigation and orientation system module includes a barometric altimeter, a three-axis angular velocity sensor, a three-axis linear acceleration sensor, a three-axis magnetic field sensor and a computer connected to them via communication channels. The interface for connecting video transmitters is designed with the ability to connect digital and analog video transmitters. The radio channel receiver interface and the SBUS inverter are connected in series or in parallel.

The claimed device operates as follows.

The flight controller is located on the UAV, sending commands to the electronic speed controller, the controller controls the flight dynamics of the device, controlling all electric motors.

After power is supplied from the electronic speed controller or USB connector to the controller, the input voltage is converted to a supply voltage of 3.3V, 5V and 9V, the calculator and all sensors connected to it are initialized. This is signaled by the LED module and the sound emitter, if the latter is connected to the controller.

The flight controller allows connecting external expansion modules of various purposes for unification in the information-measuring and control system via an asynchronous interface, each of which is launched and initialized simultaneously with the computer module, and which can be switched off via controlled switches. The orientation and navigation system module produces an orientation vector, on the basis of which control signals are formed in the control system located in the computer, which are transmitted to the apparatus engines via the speed controller. The sensors are initially logically connected: based on the totality of readings from all sensors included in the controller, the position of the control object in various coordinate systems is calculated. Since the sensors are located on one board, their mechanical connection is maximally rigid compared to if they were located on different boards.

The signal from the OES is superimposed with telemetry data, which is fed to the video transmitter module and from the video transmitter to the operator. The video transmitter is controlled using a computer. The use of receiver interfaces, the OES selection module and video transmitter interfaces together with the on-screen menu module, two OES interfaces, which must be located on the device in a way that ensures the maximum viewing radius, allows the device to be controlled and control signals to be fed to it at a distance and to receive an image directly from several OES with telemetry data, which increases the viewing radius of the device, improves the reliability of the system as a whole and allows for a wider range of tasks to be solved and the device to be used in autonomous, automatic, semi-automatic and manual control modes.

Control signals to the motors and telemetry data are transmitted from the computer to the computer using the electronic speed controller interface. Control signals to the servo drives are sent by the computer.

For storing, using, refining, updating, accumulating, collecting, systematizing, and analyzing sensor data, control signals from the computer and the device operator, coming from the radio channel receiver, and the device state vector, a memory module is used, connected via a communication channel to the computer.

Programming, software updating, debugging, route recording, and loading telemetry data into the controller is done via the USB connector.

Example.

A general-purpose flight controller for a multirotor unmanned aerial vehicle was implemented as a prototype at the Applicant enterprise (Fig. 2). The claimed device successfully passed testing and confirmed the achievement of the technical result as a result of flight tests, especially in terms of increasing the operator's viewing angle in open terrain.

The developed flight controller is easily reproducible, including in small-scale production, since standard industrial equipment can be used to implement the claimed device, and the proposed invention can be implemented in existing information-measuring and control systems of unmanned vehicles: ground, surface, and aircraft.

Claims (5)

1. A general-purpose flight controller for a multirotor unmanned aerial vehicle, characterized in that it is made on the basis of a printed circuit board containing the following located thereon: a power supply module with the ability to convert the input voltage into a voltage of 5V, 3.3V and 9V, a computer module and connected to it - an on-screen menu module and a video transmitter interface connected to it, a servo drive control module, a supply voltage monitoring module with protection against incorrect power-up and an electronic speed controller interface, a switch control module, an audio emitter interface, an optical-electronic means (OEM) selection module, a connected radio channel receiver interface and an SBUS inverter, an asynchronous interface module, a navigation and orientation system module, a memory module and a USB connector, wherein two OEM interfaces are organized for working with the OEM selection module, connected to the on-screen menu module via the video transmitter interface, the electronic speed controller interface module is connected directly to the computer module. 2. The controller according to item 1, characterized in that the navigation and orientation system module includes a barometric altimeter, a three-axis angular velocity sensor, a three-axis linear acceleration sensor, and a three-axis magnetic field sensor. 3. The controller according to item 1, characterized in that the interface for connecting video transmitters is designed with the possibility of connecting digital and analog video transmitters. 4. The controller according to item 1, characterized in that the radio channel receiver interface and the SBUS inverter are connected in series. 5. The controller according to item 1, characterized in that the radio channel receiver interface and the SBUS inverter are connected in parallel.