Composite aircraft with flight and water surface navigation functions and control method thereof

Abstract

The invention discloses a composite aircraft with flight and water surface navigation functions and a control method thereof. The composite aircraft comprises a fuselage, a power unit, a floating unit and a control unit, the floating unit is used for providing reliable and stable buoyancy and propulsive force for the composite aircraft on the water surface, and the navigation boosting module plays a key role in providing the thrust, so that the composite aircraft can flexibly move on the water surface; water surface translation and steering operation can be realized by virtue of four rotor modules; and the flight control module fuses attitude information, distance information, position information and remote control information to accurately control the composite aircraft, so that mode switching and stable control effects of flight, slow descent, floating and omnidirectional navigation can be realized. According to the scheme, the dual functions of flight and water surface navigation of the composite aircraft are achieved, and the application scene of the composite aircraft is greatly expanded.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aircraft technology, in particular to a composite aircraft with flight and water surface navigation functions and a control method thereof, and is especially suitable for water rescue, water area monitoring and the like. BACKGROUND

[0002] The existing aircraft (such as multi-rotor unmanned aerial vehicles) mainly rely on rotor power to realize aerial flight, but cannot land or navigate on the water surface. Some improved schemes realize floating by increasing floating blocks, but still have some problems.

[0003] Touching water attitude is uncontrollable: the traditional scheme lacks accurate height detection and attitude correction when landing on the water surface, and is easy to cause rollover due to waves or tilting;

[0004] Power switching is not continuous: the power system switching between flight mode and floating mode relies on manual operation, has slow response speed and low safety;

[0005] Water surface movement ability is poor: after floating, it is passively moved by water flow or wind force, and cannot actively navigate. SUMMARY

[0006] In view of the problems in the prior art, the present application provides a composite aircraft with flight and water surface navigation functions and a control method thereof.

[0007] In a first aspect, the present application provides a composite aircraft with flight and water surface navigation functions, comprising: a fuselage having a main body structure constructed of carbon fiber material, and four through channels on the upper surface of the main body structure; a power unit including four rotor modules and respectively arranged in the four channels of the fuselage, for forming a descending airflow in the corresponding channel by rotating to generate the flight lift of the composite aircraft; a floating unit including a buoyancy generating module and a navigation boosting module, the buoyancy generating module is arranged on the lower surface of the fuselage and is used to generate the buoyancy of the composite aircraft floating on the water surface, the navigation boosting module is arranged at the back of the fuselage and is used to generate the propelling force of the composite aircraft navigating on the water surface; the control unit includes a flight control module, a receiver module and a sensor module arranged inside the fuselage, the sensor module is used to obtain the attitude information, distance information and position information of the fuselage, the receiver module is used to obtain the wireless transmission of the remote control information from the remote controller, and the flight control module is used to control the power unit and the floating unit according to the attitude information, the distance information, the position information and the remote control information so that the composite aircraft takes off and lands, flies in the air and navigates on the water surface in the corresponding control mode.

[0008] Further, the sensing module comprises a laser radar, which is directed downward of the fuselage, used to emit laser beams with wavelength ranging from 905nm to 1550nm, receive echo signals and filter water wave noise under complex reflection conditions, and output distance information between the compound aircraft and water surface to the flight control module.

[0009] Further, the sensing module further comprises a GPS module, which is in signal connection with the flight control module, used to obtain GPS signals and calculate position information, speed and acceleration information of the compound aircraft, and transmit the obtained information to the flight control module, wherein the speed and acceleration information are used to generate attitude information of the compound aircraft.

[0010] Further, each of the four rotor modules comprises a first brushless motor and a rotor mounted on a rotating shaft of the first brushless motor; the first brushless motor is fixed in a corresponding channel of the fuselage through a support arm; and the four channels on the fuselage are distributed according to four corners of a rectangle.

[0011] Further, the power unit further comprises a battery module, a current meter and an electronic speed controller module; the battery module is used to provide direct current power; the current meter is connected with the battery module, used to read current values output by the battery module in real time and transmit to the flight control module; and the electronic speed controller module is connected with the battery module, comprising four electronic speed controllers, respectively obtaining PWM signals from the flight control module, and respectively outputting corresponding current to each rotor module, so as to independently adjust rotating speed of the first brushless motor in each rotor module.

[0012] Further, the buoyancy generating module adopts a lightweight waterproof material, one end of the buoyancy generating module is conical and extends from the lower surface of the fuselage to the head side of the fuselage, and the other end is cylindrical and extends from the lower surface of the fuselage to the tail side of the fuselage; the buoyancy generating module can reduce the resistance received by the compound aircraft when sailing on water surface; and the buoyancy generating module is internally provided with a cavity structure for accommodating the battery module, and is further used to provide assembly space and waterproof protection for the battery module.

[0013] Further, the navigation boost module comprises a second brushless motor and a rotor mounted on a rotating shaft of the second brushless motor; the second brushless motor is arranged at the tail of the fuselage, and is connected with the flight control module through a driver, used to drive the rotor to rotate under the control of the flight control module, so as to drive the compound aircraft to sail on water surface.

[0014] Further, the flight control module is capable of parsing a control mode from the remote control information, the control mode being a flight mode, a water slow descent mode or a floating mode; in the flight mode, the flight control module is capable of enabling each rotor module in the power unit based on the attitude information and the position information through a PID algorithm to automatically stabilize the yaw angle, the roll angle, the pitch angle, the ground speed, the lifting speed and the attitude of the fuselage, and to enable the compound aircraft to take off and fly in the air under the control of the remote controller; in the water slow descent mode, the flight control module is capable of obtaining geographic height data of the compound aircraft in the air according to the position information, and obtaining relative distance data between the compound aircraft and the water surface according to the distance information, the flight control module is further capable of real-time regulating and controlling the power unit based on the geographic height data and the relative distance data, and enabling the compound aircraft to approach the water surface at a preset descending speed, and gradually reducing the output power of each rotor module in the power unit through a PID algorithm and real-time correcting the pitch angle and the roll angle of the fuselage until the compound aircraft touches the water with a horizontal attitude and completely floats on the water surface; in the floating mode, the flight control module is capable of enabling the navigation boost module in the floating unit to enable the compound aircraft to navigate on the water surface under the control of the remote controller; the flight control module is further capable of enabling each rotor module in the power unit to enable the compound aircraft to translate and turn on the water surface under the control of the remote controller.

[0015] According to a second aspect, the application provides a control method for a composite aircraft, the composite aircraft being the composite aircraft mentioned in the first aspect, the control method comprising: the flight control module obtaining remote control information from a remote controller and parsing to obtain a control mode of the composite aircraft, the control mode being a flight mode, a water landing mode or a floating mode; the flight control module obtaining attitude information, distance information and position information of the fuselage; when the control mode is switched to the flight mode, the flight control module parses the remote control information to obtain flight control instructions, so that the composite aircraft is controlled by the remote controller to take off and land and fly in the air, and the flight control module enables each rotor module in the power unit based on the attitude information and the position information through a PID algorithm to automatically stabilize the yaw angle, roll angle, pitch angle, ground speed, lifting speed and attitude of the fuselage; when the control mode is switched to the water landing mode, the flight control module obtains geographic height data of the composite aircraft in the air according to the position information, and obtains relative distance data between the composite aircraft and the water surface according to the distance information, the flight control module further controls the power unit in real time based on the geographic height data and the relative distance data, and enables the composite aircraft to approach the water surface at a preset descending speed, and gradually reduces the output power of each rotor module in the power unit through a PID algorithm and real-time corrects the pitch angle and roll angle of the fuselage until the composite aircraft touches the water with a horizontal attitude and completely floats on the water surface; when the control mode is switched to the floating mode, the flight control module parses the remote control information to obtain navigation control instructions, so that the composite aircraft enables the navigation propulsion module in the floating unit to drive the composite aircraft to navigate on the water surface under the control of the remote controller, and the flight control module enables each rotor module in the power unit to drive the composite aircraft to translate and turn on the water surface.

[0016] Further, in the floating mode, the flight control module further obtains throttle control data and horizontal control data from the navigation control instructions and distributes corresponding control channels, adjusts the power output by the navigation propulsion module in the floating unit through the control channel corresponding to the throttle control data, and adjusts the differential speed between each rotor module in the power unit through the control channel corresponding to the horizontal control data.

[0017] The application has the following beneficial effects:

[0018] The composite aircraft with the flight and water surface navigation functions and the control method thereof according to the above embodiment provide the floating unit to provide the buoyancy and power for the water surface navigation of the composite aircraft, so that the composite aircraft has the capability of stopping and moving on the water surface, and thus the composite aircraft can realize the flight operation and the water surface operation, and widens the working field and the use scene of the aircraft while retaining the advantage of the flexibility of the aircraft.

[0019] In addition, the composite aircraft is configured with the navigation boost module to provide the thrust in the floating mode, and the differential adjustment of the rotor modules is implemented to realize the translation and steering on the water surface, so that the composite aircraft is more flexible in the water surface movement, and the independent navigation boost module enables the thrust to be better utilized, thereby reducing the power consumption of the composite aircraft. The flight control module of the present application fuses the attitude information, the distance information, the position information and the remote control information to accurately control the composite aircraft, which is beneficial to realize the mode switching and stable control of the flight, the slow descent, the floating and the omnidirectional navigation. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The whole structure three-dimensional schematic diagram of the composite aircraft in an embodiment of the present application is shown in the figure.

[0021] Figure 2 The front view of the composite aircraft in an embodiment of the present application is shown in the figure.

[0022] Figure 3 The hardware connection block diagram of the control unit in an embodiment of the present application is shown in the figure.

[0023] Figure 4 The mode switching flowchart in an embodiment of the present application is shown in the figure.

[0024] Figure 5 The water surface navigation function control algorithm block diagram in an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0025] The specific embodiments of the present application are further described in detail below with reference to the accompanying drawings. It should be noted that the following embodiments are only used to explain the technical solutions of the present application, and are not used to limit the protection scope of the present application.

[0026] REFERENCE Figures 1-2 The physical structure and the core components of the composite aircraft are described in detail in the embodiment, that is, the fuselage 1 (refer to Figure 1 , Figure 2 ) has a main body structure made of carbon fiber material, and the upper surface of the main body structure has four through channels, which are manufactured by an integral molding process to reduce the weight of the aircraft body and facilitate flight and floating. The fuselage 1 integrates the floating unit 2, the power unit 3 and the control unit 4.

[0027] The floating unit 2 (refer to Figure 1, Figure 2 ) includes a buoyancy generating module 21 and a navigation boosting module 22, wherein the buoyancy generating module 21 is arranged on the lower surface of the fuselage 1 and used to generate the buoyancy of the compound aircraft floating on the water surface, and the navigation boosting module 22 is arranged on the rear of the fuselage 1 and used to generate the propelling force of the compound aircraft navigating on the water surface.

[0028] The power unit 3 (refer to Figure 1 , Figure 2 ) includes four rotor modules 31 and is arranged in four channels of the fuselage 1 respectively, and the four channels are distributed according to the four corners of a rectangle. The power unit 3 is used to generate the flight lift of the compound aircraft by rotating the downwash in the corresponding channel.

[0029] The control unit 4 includes a flight control module 41, a receiver module 42 and a sensor module 43 arranged inside the fuselage 1, which are used to obtain the attitude and motion state of the compound aircraft in real time and control the action of the compound aircraft. Among them, the sensor module 43 is used to obtain the attitude information, distance information and position information of the fuselage 1, the receiver module 42 is used to obtain the wireless transmission of the remote control information from the remote controller; the flight control module 41 is used to control the power unit 3 and the floating unit 2 according to the attitude information, distance information, position information and remote control information so that the compound aircraft takes off and lands, flies in the air and navigates on the water surface in the corresponding control mode.

[0030] In one specific embodiment, the buoyancy generating module 21 is composed of light foam material, the surface is treated with hydrophobic treatment, one end is tapered and extends to the head side of the fuselage 1 on the lower surface of the fuselage 1, the other end is cylindrical and extends to the tail side of the fuselage 1 on the lower surface of the fuselage 1, and is symmetrically distributed on both sides of the bottom of the fuselage 1, providing the required buoyancy for floating on the water surface (required buoyancy ≥ 1.5 times the gravity of the fuselage), and the navigation boosting module 22 is installed on the rear of the fuselage 1 and includes a second brushless motor 221 and a rotor 222 arranged on the rotating shaft of the second brushless motor 221, the rotor 222 is connected with the rotating shaft of the motor through a waterproof bearing, and is used to provide the main propelling force when navigating on the water surface. The buoyancy generating module 21 can reduce the resistance received by the compound aircraft when navigating on the water surface.

[0031] In one specific embodiment, each of the four rotor modules 31 includes a first brushless motor 311 and a rotor arranged on the rotating shaft of the first brushless motor 311, and the first brushless motor 311 is fixed in the corresponding channel of the fuselage 1 through a support arm made of light alloy material. The four channels are distributed according to the four corners of a rectangle to ensure that the rotor rotates to form uniform downwash.

[0032] In one specific embodiment, referring to Figure 3, the power unit 3 further comprises a battery module 34, a current meter 33 and an electronic speed controller module 32; the battery module 34 is used to provide direct current power; the current meter 33 is connected with the battery module 34, used to read the current value output by the battery module 34 in real time and transmit to the flight control module 41; the electronic speed controller module 32 is connected with the battery module 34, comprising four electronic speed controllers and respectively acquiring PWM signals from the flight control module 41, and respectively outputting corresponding current to each rotor module 31, so as to independently adjust the rotating speed of the first brushless motor 311 in each rotor module 31. It can be understood that each first brushless motor 311 drives a rotor 312, and the rotating speed is controlled by receiving the PWM signal of the flight control module 41 through the electronic speed controller module 32, so as to realize the flight attitude adjustment. In a specific embodiment, the four electronic speed controllers of the electronic speed controller module 32 are respectively connected with the flight control module 41 through independent PWM signals, the flight control module 41 receives the control signal of the remote controller, combines the current attitude and motion information of the compound aircraft, and generates the PWM control signal according to the current mode of the compound aircraft, and the electronic speed controller module 32 drives the four first brushless motors 311 to control the action of the compound aircraft according to the PWM signal. Of course, the current meter 33 in the power unit 3 is used to shunt the current output by the battery module 34 to the four first brushless motors 311, and is also used to detect the voltage and current in real time and feed back to the flight control module 41; the battery module 34 is located below the fuselage 1, and provides energy for the motion of the compound aircraft.

[0033] In a specific embodiment, the current meter 33 reads the current value output by the battery module 34 in real time and transmits to the flight control module 41, and the flight control module 41 can judge the remaining battery capacity according to the current data; the four electronic speed controllers of the electronic speed controller module 32 independently adjust the rotating speed of each first brushless motor 311, and the response speed is not more than 10ms.

[0034] In a specific embodiment, the sensing module 43 comprises a laser radar 44 and a GPS module 45; the laser radar 44 is directed downward of the fuselage 1, used to emit laser beams with wavelength range of 905nm to 1550nm, receive the echo signal and filter the water wave noise under complex reflection conditions, and output the distance information between the compound aircraft and the water surface to the flight control module 41; the GPS module 45 is signal connected with the flight control module 41, used to acquire the GPS signal and solve the position information, speed and acceleration information of the compound aircraft, the speed and acceleration information is used to generate the attitude information of the compound aircraft, and the position information is acquired and transmitted to the flight control module 41 through IIC protocol.

[0035] In a specific embodiment, the receiver module 42 is used to acquire the remote control signal of the remote controller through radio, and communicate with the flight control module 41 through SBUS protocol, so that the flight control module 41 can switch the flight mode according to the remote controller command, or further control the rotor module 31 through the PWM signal, so as to realize the action control of the compound aircraft through the remote controller.

[0036] In one embodiment, the buoyancy generating module 21 is made of light and waterproof material, with one end tapered and extending from the lower surface of the fuselage 1 to the head side of the fuselage 1, and the other end cylindrical and extending from the lower surface of the fuselage 1 to the tail side of the fuselage 1. The interior of the buoyancy generating module 21 is provided with a cavity structure for accommodating the battery module 34, which also provides assembly space and waterproof protection for the battery module 34, preventing direct contact between the battery module 34 and water.

[0037] In one embodiment, the navigation boost module 22 includes a second brushless motor 221 and a rotor 222 provided on the rotating shaft of the second brushless motor 221. The second brushless motor 221 is provided at the tail of the fuselage 1 and connected to the flight control module 41 through a driver. The flight control module 41 sends a PWM signal to control the second brushless motor 221 through an independent electronic speed controller, which is a special component of the floating unit 2 and is used to control the rotating speed of the second brushless motor 221. When the compound aircraft is in water navigation mode, the second brushless motor 221 provides a propelling force for the aircraft's movement on the water surface.

[0038] In one embodiment, the flight control module 41 in the control unit 4 can parse the control mode from the remote control information, and can configure the control mode of the compound aircraft as flight mode, water landing mode or floating mode.

[0039] In flight mode, i.e. when the flight control module 41 confirms that the control mode is switched to flight mode, the flight control module 41 can enable each rotor module 31 in the power unit 3 based on attitude information and position information through a PID algorithm to automatically stabilize the yaw angle, roll angle, pitch angle, ground speed, lift speed and attitude of the fuselage 1, and can enable the compound aircraft to take off and fly in the air under the control of the remote controller. For example, the flight control module 41 controls the compound aircraft to fly according to the conventional four-rotor aircraft control method. When no instruction is received from the remote controller, the flight control module 41 reads the current state of the aircraft from the sensing module 43 and automatically controls the aircraft to maintain stability. The receiver module 42 reads the instruction after receiving the radio signal from the remote controller and transmits the instruction to the flight control module 41. The flight control module 41 controls the first brushless motor 311 in the four rotor modules 31 to rotate at different speeds, thereby controlling the aircraft to fly according to the command.

[0040] In the water slow descent mode, i.e. when the flight control module 41 confirms that the control mode is switched to the water slow descent mode, the flight control module 41 can obtain the geographic height data of the compound aircraft in the air according to the position information, and obtain the relative distance data between the compound aircraft and the water surface according to the distance information. The flight control module 41 can also real-time regulate the power unit 3 based on the geographic height data and the relative distance data, and make the compound aircraft approach the water surface at a preset descent rate, and gradually reduce the output power of each rotor module 31 in the power unit 3 and real-time correct the pitch angle and roll angle of the fuselage 1 by the PID algorithm, until the compound aircraft touches the water with a horizontal attitude and completely floats on the water surface. For example, the laser radar 44 emits laser beams with a wavelength range of 905nm to 1550nm, receives the echo signal and filters the water wave noise under complex reflection conditions, and outputs the distance information between the compound aircraft and the water surface to the flight control module 41. The flight control module 41 controls the aircraft landing speed by the PID algorithm, so that the aircraft can smoothly slow down to the water surface.

[0041] In the floating mode, i.e. when the flight control module 41 confirms that the control mode is switched to the floating mode, the flight control module 41 analyzes the remote control information to obtain the navigation control instruction, so that the compound aircraft enables the navigation boost module 22 in the floating unit 2 to drive the compound aircraft to navigate on the water surface under the control of the remote controller, and the flight control module 41 enables each rotor module 31 in the power unit 3 to drive the compound aircraft to translate and turn on the water surface. For example Figure 5 In the floating mode, the receiver module 42 reads the instructions of the remote controller and transmits them to the flight control module 41 through the IIC protocol. The flight control module 41 controls the second brushless motor 221 behind the fuselage 1 according to the throttle value of the remote controller, and the rotor 222 driven by the second brushless motor 221 provides the main power for the aircraft floating on the water surface. The flight control module 41 controls the differential speed of the diagonal brushless motors in the rotor module 31 according to the yaw channel value of the remote controller, to realize the self-rotation action around the z-axis. The flight control module 41 controls the differential speed of the adjacent brushless motors in the rotor module 31 according to the direction channel value of the remote controller, to realize the four-rotor auxiliary motion of the aircraft moving forward and backward on the water surface and the left-right translation (the main power source of the forward and backward motion is the second brushless motor 221 behind the fuselage 1).

[0042] Reference Figures 1-3 The embodiment provides the calculation of the buoyancy generating module 21 (reference Figure 1 , Figure 2 ) specifications. The buoyancy generating module 21 adopts a lightweight waterproof material and needs to meet the requirement of providing a buoyancy of not less than 1.5 times the weight of the fuselage. The required buoyancy calculation method is as follows: the weight of the aircraft itself is about 1kg, and the weight of the lightweight foam material can be ignored. Under the condition that the rotor does not interfere with the lift, the maximum bottom area of the buoyancy generating module is about 300cm 2 . According to the Archimedes buoyancy formula

[0043] F 浮 = p 液 gV 排 (1)

[0044] If you want to provide 1.5 times the body gravity, the buoyancy should meet the following formula

[0045] V 排 = sh (2)

[0046] F 浮 ≥ 1.5g (3)

[0047] Then, according to formula (1) (2) (3), the value of g in the normal use environment of the aircraft is 9.8 N / kg, and the thickness of the buoyancy generating module should be calculated to satisfy h≥3.3cm. Considering the influence of the size and shape of the buoyancy generating module on the center of gravity of the aircraft, a 3.5cm thick foam material is selected as the buoyancy generating module, and it is symmetrically distributed to ensure that the buoyancy generating module can provide the buoyancy to make the composite aircraft float on the water surface, the center of gravity of the aircraft is located in the center of the aircraft, and it will not have too much influence on the wind resistance in flight mode.

[0048] In one embodiment, the conical head design of the buoyancy generating module can reduce the water surface navigation resistance, and the cylindrical tail smoothly transitions with the side surface of the tail of the fuselage 1; the waterproof structure of the battery module 34 ensures that it does not enter water within 10 minutes under 1 meter of water depth.

[0049] Based on the structure and control logic of the composite aircraft mentioned above, the switching control method of the composite aircraft between the flight mode, the water surface slow descent mode and the floating mode is specifically disclosed, and the dynamic adjustment mechanism and hardware coordination strategy during multi-mode switching are mainly described. The mode switching control process can be understood in combination with Figure 4 (mode switching flowchart) and Figure 5 (surface navigation function control algorithm block diagram).

[0050] It should be noted that the structure and mode of the composite aircraft involved can refer to Figures 1-3 , it can be known that the composite aircraft mainly includes a fuselage 1, a floating unit 2, a power unit 3 and a control unit 4. The control method in this embodiment is mainly applied to the flight control module 41 in the control unit.

[0051] The control method of the composite aircraft in the application can be described as follows:

[0052] (1) The flight control module 41 obtains the attitude information, distance information and position information of the fuselage 1.

[0053] (2) When the flight control module 41 judges that the control mode is switched to the flight mode, the flight control module 41 analyzes the remote control information to obtain the flight control instructions, so that the compound aircraft performs take-off and flight in the air under the control of the remote controller, and the flight control module 41 enables each rotor module 31 in the power unit 3 based on the attitude information and the position information through the PID algorithm to automatically stabilize the yaw angle, roll angle, pitch angle, ground speed, and lift-off speed of the fuselage 1.

[0054] (3) When the flight control module 41 judges that the control mode is switched to the water landing mode, the flight control module 41 obtains the geographic height data of the compound aircraft in the air according to the position information, and obtains the relative distance data between the compound aircraft and the water surface according to the distance information. The flight control module 41 also controls the power unit in real time based on the geographic height data and the relative distance data, and enables the compound aircraft to approach the water surface at a preset descent rate, and gradually reduces the output power of each rotor module 31 in the power unit 3 and real-time corrects the pitch angle and roll angle of the fuselage through the PID algorithm, until the compound aircraft touches the water with a horizontal attitude and completely floats on the water surface.

[0055] (4) When the flight control module 41 confirms that the control mode is switched to the floating mode, the flight control module 41 analyzes the remote control information to obtain the navigation control instructions, so that the compound aircraft enables the navigation boost module 22 in the floating unit 2 to drive the compound aircraft to navigate on the water surface under the control of the remote controller, and the flight control module 41 enables each rotor module in the power unit to drive the compound aircraft to translate and turn on the water surface.

[0056] In one embodiment, when the mode changes, the receiver module 42 communicates with the remote controller through the SBUS protocol, analyzes the mode switching signal (PWM pulse width threshold of a specific channel) in the remote controller instructions, and transmits the signal to the flight control module 41. The flight control module 41 combines the sensing module 43 to execute the mode switching decision and generate corresponding control signals; the control signals are transmitted to the power unit 3 and the navigation boost module 22 to control the attitude change of the compound aircraft.

[0057] In one embodiment, if the mode does not change, the flight control module 41 continues to execute the previous mode, the receiver module 42 receives the throttle and direction instructions of the remote controller, and transmits the PWM signals to the flight control module 41. After processing, the flight control module 41 transmits the PWM control signals to the electronic speed controller module 32 and the independent electronic speed controller, thereby controlling the four first brushless motors 311 and the navigation boost module 22 to drive the aircraft to move.

[0058] In one embodiment, in the floating mode, the flight control module 41 can also configure the signal channel of the remote controller as a special signal channel for water floating. In this mode, the remote controller can control the movement of the compound aircraft on the water surface.

[0059] In one embodiment, when the compound aircraft is in the water slow descent mode, the control unit 4 perceives the aircraft state in real time, wherein the laser radar 44 emits a laser beam with a wavelength range of 905nm to 1550nm, receives the echo signal and filters the water wave noise under complex reflection conditions, and outputs the distance information between the compound aircraft and the water surface to the flight control module 41, the flight control module 41 generates a PWM control signal and transmits the signal to the electronic governor module 32, thereby controlling the rotor module 31 to drive the aircraft to slowly descend on the water surface through a PID control algorithm; After the control unit 4 automatically detects and confirms that the compound aircraft has successfully landed on the water surface, the compound aircraft is allowed to switch to the floating mode.

[0060] Correspondingly, the control method flow of the compound aircraft can be combined with Figure 4 (Mode switching flow chart) Understand, can be described as follows:

[0061] Step 401, start stage, compound aircraft power on, each unit initialization.

[0062] Step 402, signal receiving, control unit 4 receives remote control signal from remote controller.

[0063] Step 403, judge PWM signal, control unit 4 judges the PWM signal pulse width of mode control channel in the received remote control signal, if the pulse width is within the first threshold, it indicates that the remote controller turns into flight mode (see step 404), if the pulse width is within the second threshold, it indicates that the remote controller turns into water slow descent mode (see step 405), if the pulse width is within the third threshold, it indicates that the remote controller turns into floating mode (see step 406).

[0064] Step 407, mode change judgment, judge whether the mode of the compound aircraft changes, if it changes, execute step 408, if it does not change, return to step 402.

[0065] Step 408, propeller speed adjustment, control unit 4 obtains the flight attitude of the compound aircraft, combines the current compound aircraft mode, calculates the expected motion state, and outputs the expected PWM signal to the power unit 3 to control the propeller speed.

[0066] Step 409, aircraft attitude adjustment, control unit 4 monitors the aircraft attitude in real time, combines the current compound aircraft mode, automatically calculates the expected control signal according to the expected attitude in the compound aircraft mode, and transmits the PWM signal to the power unit 3 to automatically adjust the compound aircraft attitude.

[0067] Step 410, control channel switching, the control unit 4 determines whether to deploy the remote control channel as a dedicated control signal channel according to the current mode of the composite aircraft. If adjustment is needed, the control unit 4 configures the remote control channel as a flight / float control channel, allowing the operator to control the composite aircraft in the corresponding mode. For example, in float mode, the flight control module 41 also obtains throttle control data and horizontal control data from the navigation control instructions and assigns corresponding control channels. The throttle control data is used to adjust the power output of the navigation boost module 22 in the float unit 2, and the horizontal control data is used to adjust the differential speed between the various rotor modules 31 in the power unit 3.

[0068] After performing the control channel switching operation in step 410, return to step 402 signal reception and repeat the above steps.

[0069] Reference Figures 1-3 The implementation of the signal interaction of the control unit and the water-based slow descent mode is described in the following aspects.

[0070] First, the control unit 4 is set up Figure 3 The hardware connection architecture shown has three characteristics.

[0071] (1) The flight control module 41 in the control unit 4 is the core of the entire system. It not only receives data from the perception unit, but also receives instructions from the remote control through the receiver module 42. The receiver module 42 receives instructions through the SBUS protocol and transmits the parsed instructions to the flight control module 41.

[0072] (2) The execution layer is composed of the electronic governor module 32 and the navigation boost module 22, which are directly connected to the flight control module 41. The flight control module 41 communicates with the electronic governor module 32 through PWM signals, outputting four groups

[0073] of PWM signals to control the speed of the rotors. In addition, the flight control module 41 also controls the navigation boost module 22 to assist the aircraft in navigation operations on the water surface.

[0074] (3) The perception layer includes the laser radar 44 and the GPS module 45, which are connected to the flight control module 41 through the IIC protocol. These two modules are responsible for collecting environmental and location data and transmitting these data to the flight control module 41. The flight control module 41 uses the built-in Kalman filter algorithm to process and fuse these data, outputting accurate height information.

[0075] Second, the water-based slow descent control process is set up, including the following steps.

[0076] Step 1: The remote control sends a mode switching instruction, triggering the flight control module 41 to enter the water-based slow descent mode.

[0077] Step 2: Flight control module 41 starts laser radar 44 and GPS module 45 to measure the height of the composite aircraft from the water surface in real time. The raw data measured is processed by the built-in Kalman filter algorithm and output.

[0078] Step 3: Start adaptive buffer stage PID control algorithm, dynamically stabilize yaw angle, pitch angle and roll angle, and control the aircraft to slowly descend.

[0079] Reference Figure 5 This embodiment describes the cooperative control logic of the navigation boost module 22 and the rotor module 31:

[0080] When the flight control module 41 switches to the floating mode, the signals of the remote controller are configured as a special signal channel for controlling the floating movement of the composite aircraft on the water surface.

[0081] Correspondingly, the water surface navigation function control method flow of the composite aircraft can be combined Figure 5 (Water surface navigation function control algorithm block diagram) Understand, described as follows:

[0082] Step 501, start stage, the composite aircraft enters the starting state of the work flow.

[0083] Step 502, signal receiving, the control unit 4 receives the special signal channel signal of the remote controller.

[0084] Step 503, judge PWM signal, the control unit 4 judges the PWM signal pulse width of the special signal channel in the received remote control signal. If the pulse width is within the fourth threshold, it indicates that the composite aircraft performs the forward action (see step 504), and if the pulse width is within the fifth threshold range, it indicates that the composite aircraft performs the turning action (see step 505).

[0085] Step 506, direction change judgment, judge whether the direction of the composite aircraft changes, if the direction changes, execute step 507; if not, return to step 502 to receive signals again.

[0086] Step 507, adjust the propeller speed, the control unit 4 calculates and outputs the expected PWM signal to the power unit 3 according to the direction change and other conditions, adjusts the propeller speed, to adapt to the new navigation requirements.

[0087] Step 508, navigation direction adjustment, the control unit 4 monitors the attitude of the composite aircraft in real time, automatically solves the expected control PWM signal based on the current action of the composite aircraft, and transmits the PWM signal to the power unit 3, further accurately controls the navigation direction of the composite aircraft.

[0088] After the sailing direction adjustment operation of step 508 is performed, return to step 502 signal receiving, repeat the above steps, continue to control the water surface sailing state of the composite aircraft.

[0089] The thrust distribution mechanism is provided, which embodies the following two points.

[0090] (1) Sailing boost module 22: receive remote control throttle instruction, control the second brushless motor 221 rotation speed (0~100% PWM duty ratio), the driver of the second brushless motor 221 receives the PWM signal of the flight control module 41, and the duty ratio 0-100% corresponds to the propulsion force 0-5N, which provides the main propulsion force and meets the adjustment requirement of water surface speed 0-2m / s.

[0091] (2) Rotor module 31: according to the direction instruction, adjust the rotation speed difference of the motor group:

[0092] Left translation: increase the speed of the right front and rear motor group, and decrease the speed of the left front and rear motor group to generate a left moment.

[0093] Right translation: increase the speed of the left front and rear motor group, and decrease the speed of the right front and rear motor group to generate a right moment.

[0094] Forward translation: increase the speed of the rear left and right motor group, and decrease the speed of the front left and right motor group to generate a forward moment.

[0095] Rear translation: increase the speed of the front left and right motor group, and decrease the speed of the rear left and right motor group to generate a rear moment.

[0096] Left yaw: increase the speed of the left front and right rear motor group, and decrease the speed of the right front and left rear motor group to generate a counterclockwise torque.

[0097] Right yaw: increase the speed of the right front and left rear motor group, and decrease the speed of the left front and right rear motor group to generate a clockwise torque.

[0098] It should be noted that the throttle control data corresponds to the PWM pulse width range of 1000-2000us, and the horizontal control data is adjusted by adjusting the rotation speed difference of the left and right rotor modules ±500rpm to realize the translation speed adjustment of ±0.5m / s.

[0099] The water surface self-stabilization control strategy is provided, and the proportion is compensated by the roll angle: if the control unit 4 detects that the roll angle is greater than 25° (<-25°), the PID algorithm is intervened to adjust the differential speed of the left motor group and the right motor group to restore the horizontal attitude.

[0100] The above is a further detailed description of the present application in combination with a specific embodiment, which cannot be considered as limiting the specific implementation of the present application to these descriptions. For ordinary skilled persons in the technical field to which the present application belongs, some simple deductions or substitutions can be made without departing from the inventive concept of the present application.

Claims

1. A compound aircraft having the functions of flight and water travel, characterized by, The utility model relates to a kind of composite aircrafts, including: Machine body, with the main structure of carbon fiber material construction, and the upper surface of main structure has four through channels; Power unit, including four rotor modules and being respectively arranged in the four channels of the machine body, for forming descending airflow in corresponding channel by rotating to generate the flight lift of the composite aircraft; Floating unit, including buoyancy generating module and navigation boost module, the buoyancy generating module is arranged on the lower surface of the machine body and is used to generate the buoyancy of the composite aircraft floating on the water surface, the navigation boost module is arranged on the back of the machine body and is used to generate the propelling force of the composite aircraft sailing on the water surface; Control unit, including flight control module, receiver module and sensing module arranged in the machine body, the sensing module is used to obtain the attitude information, distance information and position information of the machine body, the receiver module is used to obtain the remote control information of wireless transmission from remote controller, the flight control module is used to control the power unit and the floating unit according to the attitude information, distance information, position information and remote control information to make the composite aircraft take off and land, fly in the air and sail on the water surface in corresponding control mode.

2. The composite aircraft of claim 1, wherein, The sensing module includes a laser radar that points downward of the machine body, is used to emit laser beam with wavelength range of 905nm to 1550nm, receive echo signal and filter water surface wave noise under complex reflection condition, and output distance information between the composite aircraft and water surface to the flight control module.

3. The composite aircraft of claim 2, wherein, The sensing module further includes a GPS module that is signal connected with the flight control module, is used to obtain GPS signal and solve position information, speed and acceleration information of the composite aircraft, and transmit the obtained information to the flight control module, and the speed and acceleration information is used to generate the attitude information of the composite aircraft.

4. The composite aircraft of claim 1, wherein, Each of the four rotor modules includes a first brushless motor and a rotor mounted on a rotating shaft of the first brushless motor.

5. The composite aircraft of claim 4, wherein, The power unit further includes a battery module, a current meter and an electronic speed controller module. The battery module is used to provide direct current power. The current meter is connected with the battery module, is used to read current value output by the battery module in real time and transmit to the flight control module. The electronic speed controller module is connected with the battery module, includes four electronic speed controllers, respectively obtains PWM signal from the flight control module, and respectively outputs corresponding size current to each rotor module, to independently adjust rotating speed of the first brushless motor in each rotor module.

6. The composite aircraft of claim 5, wherein, The buoyancy generating module adopts light waterproof material, one end of the buoyancy generating module is conical and extends to the head side of the machine body on the lower surface of the machine body, the other end is columnar and extends to the tail side of the machine body on the lower surface of the machine body;The buoyancy generating module can reduce the resistance received by the composite aircraft when sailing on the water surface. The buoyancy generating module is internally provided with a cavity structure for accommodating the battery module, and is also used for providing assembly space and waterproof protection for the battery module.

7. The composite aircraft of claim 6, wherein, The navigation assisting module comprises a second brushless motor and a rotor provided on a rotating shaft of the second brushless motor; the second brushless motor is arranged at a tail of the fuselage and is connected with the flight control module through a driver, and is used for rotating the rotor under the control of the flight control module to drive the compound aircraft to sail on the water surface.

8. The compound aircraft of any one of claims 1 to 7, wherein, The flight control module can analyze a control mode from the remote control information, and the control mode is a flight mode, a water surface slow descending mode or a floating mode. In the flight mode, the flight control module can enable each rotor module in the power unit through a PID algorithm based on the attitude information and the position information, to automatically stabilize a yaw angle, a roll angle, a pitch angle, a ground speed, a lifting speed and an attitude of the fuselage, and can enable the compound aircraft to take off and land and fly in the air under the control of the remote controller. In the water surface slow descending mode, the flight control module can obtain geographical height data of the compound aircraft in the air according to the position information, and can obtain relative distance data between the compound aircraft and the water surface according to the distance information; the flight control module can also real-time regulate and control the power unit based on the geographical height data and the relative distance data, and can enable the compound aircraft to approach the water surface at a preset descending speed, and can gradually reduce output power of each rotor module in the power unit and real-time correct the pitch angle and the roll angle of the fuselage through the PID algorithm, until the compound aircraft touches the water with a horizontal attitude and completely floats on the water surface. In the floating mode, the flight control module can enable the navigation assisting module in the floating unit, so that the compound aircraft sails on the water surface under the control of the remote controller; the flight control module can also enable each rotor module in the power unit, so that the compound aircraft translates and turns on the water surface under the control of the remote controller.

9. A control method for a compound aircraft, characterized in that, The compound aircraft is the compound aircraft in any one of claims 1-8, and the control method comprises: The flight control module obtains remote control information from the remote controller and analyzes a control mode of the compound aircraft, and the control mode is a flight mode, a water surface slow descending mode or a floating mode; The flight control module obtains attitude information, distance information and position information of the fuselage; When the control mode is switched to the flight mode, the flight control module analyzes the remote control information to obtain flight control instructions, so that the compound aircraft takes off and lands and flies in the air under the control of the remote controller, and the flight control module enables each rotor module in the power unit through a PID algorithm based on the attitude information and the position information, to automatically stabilize a yaw angle, a roll angle, a pitch angle, a ground speed, a lifting speed and an attitude of the fuselage. When the control mode is switched to the water landing mode, the flight control module obtains geographical height data of the compound aircraft in the air according to the position information and obtains relative distance data between the compound aircraft and the water surface according to the distance information. The flight control module also controls the power unit in real time based on the geographical height data and the relative distance data, so that the compound aircraft approaches the water surface at a preset descending speed, and gradually reduces the output power of each rotor module in the power unit and real-time corrects the pitch angle and roll angle of the fuselage by a PID algorithm, until the compound aircraft touches the water with a horizontal attitude and completely floats on the water surface. When the control mode is switched to the floating mode, the flight control module analyzes the remote control information to obtain navigation control instructions, so that the compound aircraft enables the navigation boost module in the floating unit to drive the compound aircraft to navigate on the water surface under the control of the remote controller, and the flight control module enables each rotor module in the power unit to drive the compound aircraft to translate and turn on the water surface.

10. The control method according to claim 9, characterized by, In the floating mode, the flight control module also obtains throttle control data and horizontal control data from the navigation control instructions and distributes corresponding control channels. The flight control module adjusts the power output by the navigation boost module in the floating unit by using the throttle control data corresponding control channel, and adjusts the differential speed between each rotor module in the power unit by using the horizontal control data corresponding control channel.

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