CN105730692B - One kind is verted the long endurance combined type aircraft of quadrotor - Google Patents

Abstract

The invention discloses a tilting four-rotor long-endurance composite aircraft, which is divided into a four-rotor system, a tilting mechanism and an aircraft main body. The four-rotor power system is four propellers driven by propeller engines; the tilting mechanism is installed in the middle of the fuselage through a tilting shaft; there are four engine support mechanisms distributed along the circumferential direction, and each engine support mechanism end One of the above-mentioned propeller engines is installed at the bottom; when the tilting axis is perpendicular to the horizontal plane, there are two propeller engines in front of the wing and two behind the wings, and they are respectively located on the left and right sides of the fuselage, symmetrical to each other; they are also located on the left and right sides of the fuselage The two propeller engines are symmetrical. When taking off vertically, the quadrotor power system mainly provides lift in the vertical direction; after takeoff, the tilting mechanism realizes the overall tilting of the quadrotor and locks it to enter the level flight mode. The invention has the advantages that the safety and reliability of the aircraft are high, and the propellers in the four-rotor power system are not blocked by the wings, so the efficiency is high and the efficiency of the wings is improved.

Description

A tilting quadrotor long-endurance composite aircraft

technical field

The invention belongs to the field of aircraft design, and relates to a layout form of a novel vertical take-off and landing aircraft, in particular to an aircraft layout which utilizes the integral tilting of four rotors to realize vertical take-off and landing and then converts to a level flight state.

Background technique

my country has vast maritime regulatory waters. The area of some waters in the South China Sea alone is 3.56 million square kilometers. The southernmost Zengmu Shoal is 2,000 kilometers away from the mainland. At present, my country's maritime sector is mainly equipped with small and medium-sized ships, which can only take off and land carrier-based helicopters or small fixed-wing aircraft due to ship conditions. Shipborne helicopters are slow and have a short flight time, while small fixed-wing aircraft have single functions, short flight time and difficult recovery. When an emergency occurs, it is difficult for existing aircraft to make an effective emergency response. Therefore, there is an urgent need for an unmanned aerial vehicle that can take off and land vertically on the deck of small and medium-sized ships, and can cruise at high speed like a fixed wing during long voyage, so as to enhance my country's maritime supervision capabilities. At the same time, the UAV can also be used in cities, forests, Gobi and other areas lacking conditions for taxi takeoff and landing, to perform tasks such as urban planning, public security monitoring, disaster area observation, or battlefield reconnaissance.

At present, the existing unmanned vertical take-off and landing schemes are mainly divided into the following categories: unmanned helicopter, power tilting type, tailstock type, compound power type and the derived rotor conversion type. The cruising speed and forward efficiency of unmanned helicopters are not as good as those of fixed wings; after the power tilting aircraft takes off, each engine tilts forward respectively. During the tilting process, the dynamic relationship between the propeller disc and the engine and the fuselage makes the control system very complicated. , and the safety degree is not high; the tail seat type adopts the flight mode of taking off vertically and changing the pitch to level flight, but when it is placed vertically, the center of gravity is too high and the windward area is too large, which is not conducive to use in complex environments; compound power The special engine is used for vertical take-off and landing, and then the special engine is used to switch to level flight. In each flight stage, some engines do not function, resulting in dead weight; the rotor conversion type uses the unmanned helicopter to take off and land, and uses the forward The engine is converted to level flight, and the rotor is locked to become a wing during level flight. The efficiency is higher than that of compound power and unmanned helicopters. The disadvantage is that the rotor produces anti-torque action, and the power system is complicated, requiring special deflection, stop, and locking devices. In contrast, the rotor conversion aircraft is more suitable for high-speed long-distance flight, such as the U.S. V-22 "Osprey" aircraft that adopts this form of scheme. However, the tilting mechanism of the V-22 "Osprey" aircraft is relatively complicated, with high technical difficulty and high cost. In addition, the two engines of the V-22 "Osprey" aircraft are arranged on the outer section of the wing, which requires high structural strength and heavy weight. The rotor is also blocked by the wing, which affects the efficiency to a certain extent.

Contents of the invention

In view of the above problems, the present invention proposes a composite aircraft layout with four-rotor overall tilting, the four-rotor power system and the fixed wing are connected by a tiltable platform, and the vertical take-off and landing is realized through the tilting power system of the tiltable platform The transition process to level flight.

The tilting four-rotor long-endurance composite aircraft of the present invention includes a fuselage, wings, a horizontal tail and a vertical tail aircraft main body, and is characterized in that it also has a four-rotor power system and a tilting mechanism;

The four-rotor power system is four propellers driven by propeller engines; the tilting mechanism is installed in the middle of the fuselage through a tilting shaft; there are four engine support mechanisms distributed along the circumference, and each engine support mechanism One of the above-mentioned propeller engines is installed; when the tilt axis is perpendicular to the horizontal plane, there are two propeller engines in front of the wing and two behind the wings respectively, and they are respectively located on the left and right sides of the fuselage, symmetrical to each other; The two propeller engines are symmetrical.

When the aircraft takes off vertically, the four-rotor power system mainly provides lift in the vertical direction, and the flight control system controls the four propeller engines in the four-rotor power system, so that the four-rotor power system is in a normal flight state. At this time, the speed of the four propeller engines Same, turn center symmetric. When the aircraft rises to the predetermined height, it will switch to the level flight mode and control the tilt axis to rotate parallel to the horizontal plane. At this time, the aircraft is in a stable level flight state. When the aircraft lands, the tilt axis is controlled to be vertical to the horizontal plane, and the aircraft is controlled to descend slowly to achieve a vertical landing.

The advantages of the present invention are:

1. The tilting four-rotor long-endurance composite aircraft of the present invention has a low center of gravity before vertical take-off, and is more adaptable to complex sea conditions, and is suitable for islands, reefs, and military and civilian ships.

2. In the tilting four-rotor long-endurance composite aircraft of the present invention, the power system is tilted as a whole, and the parameters affecting the mechanical characteristics such as the equivalent wheelbase before and after tilting are almost unchanged, and the flight control system is greatly simplified.

3. The tilting four-rotor long-endurance composite aircraft of the present invention, after tilting, the propeller in the four-rotor power system is located near the wing, which accelerates the flow velocity of the airflow on the upper and lower surfaces of the wing, increases the equivalent airspeed in the local area, and improves efficiency of the airfoil.

4. In the tilting four-rotor long-endurance composite aircraft of the present invention, the propeller in the four-rotor power system is not blocked by the wings, and the efficiency is high.

5. The tilting four-rotor long-endurance compound aircraft of the present invention, the control mode of the four-rotor power system in the vertical take-off and landing and hovering stages is more favorable than the previous vertical take-off and landing aircraft, and the safety and reliability are higher.

Description of drawings

Fig. 1 is a front view schematic diagram of a tilting quadrotor long-endurance composite aircraft of the present invention in vertical take-off and landing mode;

Fig. 2 is a top view schematic diagram of a tilting quadrotor long-endurance composite aircraft in the vertical take-off and landing mode of the present invention;

Fig. 3 is a schematic side view of a tilting quadrotor long-endurance composite aircraft in vertical take-off and landing mode according to the present invention;

Fig. 4 is a schematic side view of a tilting quadrotor long-endurance composite aircraft in level flight mode according to the present invention.

In the picture:

1- Four-rotor power system 2- Tilt mechanism 3- Aircraft body

101-propeller 102-propeller engine 201-tilt shaft

202-Rotor system mounting frame 202a-Engine support mechanism

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

The tilting four-rotor long-endurance composite aircraft of the present invention includes a four-rotor power system 1 , a tilting mechanism 2 and an aircraft main body 3 , as shown in FIG. 1 .

The four-rotor power system 1 is composed of four propellers 101 and four propeller engines 102 to provide the flight power of the main body of the aircraft, as shown in FIG. 2 . Each propeller 101 corresponds to a propeller motor 102, which is fixedly installed on the output shaft of the propeller motor 102, and the propeller 101 is driven to rotate by the propeller motor 102 to provide flight power for the aircraft. Four propeller engines 102 are all installed on the tiltable mechanism 2 .

The tilting mechanism 2 includes a tilting shaft 201 and a rotor system mounting frame 202, as shown in Fig. 3 and Fig. 4 . Wherein, the tilting axis 201 is arranged horizontally, and is arranged under the middle part of the fuselage of the main body of the aircraft through bearings, and the two ends are respectively connected with the left and right side walls of the fuselage 1 through bearings. The rotor system mounting frame 202 is an integrated structure composed of 4 engine support mechanisms. In the embodiment, the engine support mechanism is adopted to adopt an L-shaped support rod structure 202a; the 4 engine support mechanisms 202a are circumferentially distributed and connected, and the joint positions are installed on the tilt axis 501. The four propeller engines 102 in the quadrotor power system 1 are installed on the four engine support structures 202a respectively. Therefore, during the tilting process, the rotor system mounting frame 202 can realize the rotation change from parallel to the horizontal plane to the vertical direction, and the rotation of the tilting shaft 201 can be driven, thereby realizing the change of the power output direction of the four propellers 401 in the quadrotor system 1; and for The tilting mechanism 2 is not hindered by the fuselage during the rotation process, so in the present invention, the bottom of the fuselage that is positioned at the rear of the tilting axis 201 in the aircraft fuselage is designed to be lower than the bottom surface of other positions of the fuselage, that is, the aircraft fuselage is positioned at the bottom of the tilting axis 201. The bottom of the fuselage behind the rotating shaft 201 is an inner concave surface.

Let the four propeller engines 102 be respectively the propeller engine A, the propeller engine B, the propeller engine C and the propeller engine D; when the tilting mechanism 2 is controlled to be perpendicular to the horizontal plane, the power output directions of the four propeller engines 202 are all directed downward, as Shown in Fig. 2; And propeller engine A, propeller engine B are all positioned at the front of the wing in the aircraft main body, are positioned at the left and right sides of fuselage, mutual symmetry; The left and right sides of the body are symmetrical to each other. The four propeller engines 102 are all located above the wing plane of the aircraft main body 3, and the projection of the entire four-rotor power system 1 on the horizontal plane is located outside the projection of the wings on the horizontal plane on the aircraft main body. At this time, the flight mode of the aircraft is vertical take-off and landing mode; and when the tilting mechanism 2 is tilted to be parallel to the horizontal plane, the flight mode of the aircraft is a level flight mode, as shown in Figure 3, and at this moment, the airflow generated by the four propellers 101 in the quadrotor power system 1 will be Avoiding the horizontal and vertical tail fins in the fixed wing on the main body 3 of the aircraft, avoiding aerodynamic interference, at the same time, in the quadrotor power system 1, the two propellers 101 located on the same side of the fuselage of the main body 3 of the aircraft are respectively located on the upper and lower sides of the wing, It is close to the surface of the wing, thereby accelerating the flow velocity of the airflow on the upper and lower surfaces of the wing, and the equivalent air speed in the local area increases, which improves the efficiency of the wing. As mentioned above, during the tilting process of the tilting mechanism 2 , the center of mass of the quadrotor power system 1 is always located above the vertical direction of the tilting axis 201 , which reduces the burden on the tilting mechanism 2 .

Through the above-mentioned tilting mechanism 2, almost no moment is assumed during the conversion process of the aircraft flight mode (vertical take-off and landing and flat flight), and it mainly plays the role of maintaining and changing the tilting angle. When the aircraft is in level flight mode and hover mode, the tilting axis 201 Locking, mainly plays the role of transmitting torque. Moreover, in the present invention, when the aircraft is in flight, when there is no need to perform pitch, roll and yaw control, the four propeller engines 102 rotate at the same speed, and the steering centers are symmetrical.

The flight process of the tilting four-rotor long-endurance composite aircraft of the present invention is specifically:

When taking off vertically, the four-rotor power system 1 mainly provides lift in the vertical direction, and the flight control system controls the four propeller engines 102 in the four-rotor power system 1, so that the four-rotor power system 1 is in a normal flight state; During , roll and yaw maneuvers, the flight control system can also control the four propeller engines 102 to drive the four propellers 101 to achieve differential power. After the aircraft rises to a predetermined height, it will turn into the level flight mode, and the flight control system will differentially control the four propeller motors 102, so that the four-rotor power system 1 will generate a nose-down moment (rotational moment around the tilt axis 201), and then make itself Rotate, tilting mechanism 2 carries out follow-up rotation, until tilting mechanism 2 rotates to be parallel with aircraft nose direction (horizontal direction during level flight), tilt axis 201 is locked, and aircraft is in stable level flight state at this moment. During the above process, when the aircraft is in the level flight acceleration state, the flight speed of the aircraft gradually increases, the wings begin to generate lift, and the lift directly generated by the four propellers in the quadrotor power system 1 accounts for a gradually decreasing proportion of the total lift. In level flight, the pitch, roll and yaw control of the aircraft are mainly performed by the wings and the vertical tail, and the quadrotor power system 1 can be used as an auxiliary. The aircraft landing process is similar, the tilt axis 201 is locked and released, and the flight control system performs differential control on the four propeller engines 102, so that the four-rotor power system 1 slowly adjusts its own angle, and generates a positive elevation angle to generate thrust to prevent the aircraft from advancing in the horizontal direction Component, the tilting axis 201 follows, and the aircraft enters the horizontal deceleration state. When the horizontal speed of the aircraft is reduced to 0, the tilting axis 201 rotates to be perpendicular to the horizontal plane, and the aircraft is controlled to descend slowly to achieve a vertical landing.

Claims (3)

1. A kind of tilting four-rotor long-endurance compound aircraft, comprising aircraft main body; Aircraft main body has fuselage, wing, horizontal empennage and vertical empennage, is characterized in that: also has four-rotor power system and tilting mechanism; The four-rotor power system is four propellers driven by propeller engines; the tilting mechanism is installed in the middle of the fuselage through the tilting shaft; the tilting mechanism includes a tilting shaft and a rotor system mounting frame; wherein, the tilting shaft is arranged on Below the middle part of the fuselage of the main body of the aircraft, both ends are respectively connected to the left and right side walls of the fuselage through bearings; the rotor system mounting frame is an integrated structure composed of 4 engine support mechanisms, and the engine support mechanism adopts L-shaped support rod structure; The supporting mechanisms are distributed circumferentially and connected, and the connecting positions are installed on the tilting shaft; the four propeller engines in the four-rotor power system are respectively installed on the four engine supporting mechanisms; thus, the rotor system mounting frame can be realized during the tilting process. The change of rotation from parallel to vertical to the horizontal plane will affect the rotation of the tilt axis, thereby realizing the change of the power output direction of the four propellers in the quadrotor system; the underside of other parts of the fuselage; When the above-mentioned tilting axis is perpendicular to the horizontal plane, there are two propeller engines at the front and rear of the wing respectively, and they are respectively located on the left and right sides of the fuselage, which are symmetrical to each other; at the same time, the two propeller engines on the left and right sides of the fuselage are symmetrical. 2. A tilting four-rotor long-endurance composite aircraft according to claim 1, wherein the center of mass of the four-rotor power system is always above the vertical direction of the tilting axis. 3. A tilting four-rotor long-endurance composite aircraft as claimed in claim 1, characterized in that: when the tilt axis is perpendicular to the horizontal plane, the projection of the four-rotor power system on the horizontal plane is located on the main body of the aircraft and the wings are on the horizontal plane Projection exterior on .