Multi-propeller tilt-rotor aircraft ground vehicle-mounted blowing test mechanism and test method

Abstract

The application belongs to the field of aircrafts, and particularly relates to a multi-blade tilt-rotor aircraft ground vehicle-mounted wind blowing test mechanism and a test method. The test platform expands the existing aircraft ground test method, can more truly simulate various states of the aircraft in flight, and the response states are closer to the aircraft in flight. Meanwhile, compared with the wind tunnel test, the aircraft is in a moving state, and the air is in a natural state, which is closer to the real flight environment of the aircraft, and provides a more reliable test scheme for the aircraft ground test stage.

Description

Technical Field

[0001] This invention belongs to the field of aircraft, specifically relating to a ground-based vehicle-mounted wind-blowing test mechanism and test method for multi-rotor tiltrotor aircraft. Background Technology

[0002] Currently, unmanned aerial vehicles (UAVs) are attracting attention from various industries due to their enormous potential applications in both military and civilian fields. Ground flight testing is a necessary stage in the UAV design process, and wind tunnel testing is a common ground testing method. Wind tunnel testing involves placing a model of an aircraft or other object in a wind tunnel to study gas flow and its interaction with the model, thereby understanding the aerodynamic characteristics of the actual aircraft or object. In wind tunnel testing, the test model is stationary, and the relative velocity generated by wind is used to simulate various states of the aircraft. However, the actual flight state still differs somewhat from the actual flight process. To more realistically simulate the flight state of an aircraft in the air and its interaction with the air during flight; and to expand ground flight testing of aircraft, how to realistically simulate the flight process to obtain more realistic and reliable observation results; and to provide a new testing method for developing highly reliable and high-performance aircraft, there is an urgent need in this field. Summary of the Invention

[0003] The purpose of this invention is to solve the above-mentioned problems existing in the prior art and to provide a ground vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft.

[0004] Technical solution: The present invention proposes a ground vehicle-mounted wind-blowing test mechanism for a multi-rotor tiltrotor aircraft. The test mechanism includes: a first lift tube, a yaw locking component, a second lift tube, a fixed flange, a fixed U-shaped component, a pitch bearing seat, a pitch axis, a roll axis, a roll bearing seat, a bearing seat base plate, a fuselage deck fixing plate, a fork-shaped component, and a yaw limiting component.

[0005] The second lifting tube is placed inside the first lifting tube, and the second lifting tube can slide up and down in the first lifting tube, thereby driving the entire test platform to achieve lifting movement;

[0006] The fixed U-shaped component is connected to the fuselage deck fixing plate to fix and lock the aircraft fuselage; the bearing seat base plate is connected to the fuselage deck fixing plate; the roll bearing seat is connected to the fuselage deck fixing plate and can move back and forth on the fuselage deck fixing plate; the roll shaft is connected to the roll bearing seat through a bearing to provide the platform with roll motion freedom.

[0007] The pitch axis passes through the through hole of the roll axis and is fixedly connected to the roll axis. The pitch axis is connected to the pitch bearing seat through a bearing, and the pitch bearing seat is connected to the fork-shaped component.

[0008] The fixed flange is connected to the fork-shaped component, and the second lifting pipe is connected to the fixed flange through an interference fit;

[0009] The yaw locking component cooperates with the yaw limiting component set on the first elevator tube to lock or unlock the yaw degree of freedom.

[0010] Preferably, the first lifting tube is a lifting outer carbon tube, and the second lifting tube is a lifting outer carbon tube; the lifting outer carbon tube and the lifting inner carbon tube are nested together, and the lifting inner carbon tube can slide up and down in the lifting outer carbon tube, thereby driving the entire test platform to achieve lifting movement; the carbon tube design is more conducive to sliding and rotation coordination.

[0011] Preferably, in order to achieve the effect of the center of gravity being close to the center of rotation, the fork-shaped component is set on the outside of the body and adopts a design that wraps around the body.

[0012] Preferably, the fixed U-shaped component is further provided with a fuselage outline support block to ensure that the fixed U-shaped component and the fuselage can be firmly fixed together during the test.

[0013] Preferably, the lower end of the fork-shaped component is provided with a vertically arranged long lug as a yaw locking component, and the long lug engages with the through hole on the yaw limiting component.

[0014] Preferably, the test mechanism further includes a pitch upper limit plate and a pitch lower limit plate, wherein the pitch upper limit plate is fixed to the lower end face of the fixed U-shaped part of the fuselage; and the pitch lower limit plate is fixed to the fixed flange.

[0015] This invention also proposes a ground-based vehicle-mounted wind-blowing test method for multi-rotor tiltrotor aircraft, the test method comprising the following steps:

[0016] Step S1: Install the aircraft on the ground vehicle-mounted wind test mechanism, and place the test mechanism on a movable platform.

[0017] Step S2: Adjust the combination of degrees of freedom of the test mechanism according to the test requirements;

[0018] Step S3: Conduct a wind test, observe the motion state of the aircraft on the test mechanism, and obtain the corresponding motion performance.

[0019] Preferably, in step S2, the degree of freedom combination forms include at least the degree of freedom forms corresponding to the individual release pitch attitude, the individual roll attitude, the combined heave and pitch attitude, the individual lock yaw attitude, and the fully released state.

[0020] The separate release of pitch attitude is used to observe the aircraft's pitch motion in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of aircraft control system parameters; the separate release of roll attitude is used to observe the aircraft's roll motion in the air, obtain the magnitude of the aircraft's roll motion, and guide the aircraft's roll control; the combined climb and pitch attitude is used to observe the combined climb and pitch motion form of the aircraft during the tilt transition state in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of aircraft transition state control parameters; the separate lock of yaw attitude is used to observe the aircraft's climb, pitch, and roll motion in the air, obtain the aircraft's combined climb, pitch, and roll motion coordination performance, and guide the adjustment of aircraft pitch installation angle, initial angle of attack, and other parameters; the fully released state is used to verify the coordination of the aircraft's various attitude motions in free flight.

[0021] Preferably, in step S3, when conducting the wind test, the motion platform may include at least the following motion forms: downwind motion, upwind motion, and crosswind motion.

[0022] The beneficial effects of the present invention are as follows: Compared with the prior art, the ground vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft involved in the present invention has the following advantages:

[0023] (1) This test platform expands the existing ground test methods for aircraft, and can more realistically simulate various states of aircraft in flight. Each response state is closer to the situation of aircraft in flight. At the same time, compared with wind tunnel test, the aircraft is in motion and the air is in a natural state, which is closer to the actual flight environment of the aircraft, providing a more reliable test scheme for the ground test stage of aircraft.

[0024] (2) Conventional test platforms are basically designed according to the scheme of ball joint combination lifting motion. The three rotational degrees of freedom contained in the ball joint must be in two states: all released or all locked. The lifting degree of freedom also has only two states: locked and released. A total of 4 states can be combined. The multi-rotor tilt rotor aircraft ground vehicle-mounted wind blowing test mechanism involved in this invention has four controllable degrees of freedom, namely yaw, pitch, roll and lifting degrees of freedom. All four degrees of freedom can be released or locked individually, and a total of 16 states can be combined. During the test, the flight effect of the aircraft can be observed in the state of all degrees of freedom being released, or only one or more degrees of freedom can be released and only the motion state in the direction of the released degree of freedom can be observed. It can meet the ground test requirements in multiple states and greatly expand the function of the test platform.

[0025] (3) Since the yaw axis and the lift axis coincide during the movement of the aircraft, the conventional test platform is basically designed according to the ball joint combination lift motion scheme. Its yaw motion and lift motion have the problem of coaxial motion that is difficult to decouple. This invention proposes a mechanism design scheme that achieves the decoupling of the two motions when the yaw and lift use the same motion axis. The yaw and lift motions can be realized separately.

[0026] (4) Compared with the problem that the axes of motion of conventional test platforms cannot be completely aligned with the center of gravity of the aircraft, this scheme adopts an internal structure of the aircraft, so that the axes of yaw, pitch, roll and climb all pass through the center of gravity of the aircraft. This design can more realistically reflect the various motion states of the aircraft and further improve the reliability and authenticity of the test. Attached Figure Description

[0027] The disclosure of this invention will become more apparent from the accompanying drawings. It should be understood that these drawings are merely illustrative, not to scale, and are not intended to limit the scope of the invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a functional diagram of the present invention;

[0030] Figure 3 This is a schematic diagram of the fuselage fixing structure of the present invention;

[0031] Figure 4 , Figure 5 This is a schematic diagram of the yaw, pitch, roll, and lift structure of the present invention;

[0032] Explanation of reference numerals in the attached figures:

[0033] Figure 1 The following are the contents indicated by the designation numbers: 1. Lifting outer carbon fiber tube; 2. Yaw locking component; 3. Lifting inner carbon fiber tube; 4. Lifting inner carbon fiber tube flange; 5. Fuselage fixing U-shaped component; 6. Fuselage outer support block; 7. Pitch bearing housing; 8. Pitch shaft; 9. Roll shaft; 10. Roll bearing housing; 11. Bearing housing base plate; 12. Fuselage deck fixing plate; 13. Pitch upper limit plate; 14. Pitch lower limit plate; 15. Fork-shaped component; 16. Yaw limiting component. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0035] To more realistically simulate the flight state of an aircraft and to expand the ground-based test methods for aircraft, this invention proposes a vehicle-mounted ground-based wind-blown test mechanism for multi-rotor tiltrotor aircraft. This mechanism uses a vehicle-mounted test bench to simulate the interaction between the aircraft and the air during flight. The aircraft is fixed to the test platform, and a vehicle propels it forward to achieve its flight speed. Various flight states generated during flight can be directly observed through the test platform. In this scheme, the aircraft actively moves forward while the air maintains its natural state, more realistically simulating the flight process, and the obtained observation results are more accurate and reliable. This provides a new testing method for developing highly reliable and high-performance aircraft.

[0036] The present invention will be further described below with reference to specific accompanying drawings and embodiments.

[0037] like Figure 1 As shown, the present invention mainly includes: an outer lifting carbon fiber tube 1, a yaw locking component 2, an inner lifting carbon fiber tube 3, an inner lifting carbon fiber tube flange 4, a fuselage fixing U-shaped component 5, a fuselage outer profile support block 6, a pitch bearing seat 7, a pitch shaft 8, a roll shaft 9, a roll bearing seat 10, a bearing seat base plate 11, a fuselage deck fixing plate 12, a pitch upper limit plate 13, a pitch lower limit plate 14, a fork-shaped component 15, and a yaw limiting component 16.

[0038] The specific assembly process using the above design is as follows: the fuselage fixing U-shaped part 5 is connected to the fuselage deck fixing plate 12 to fix and lock the aircraft fuselage; the bearing seat base plate 11 is bolted to the fuselage deck fixing plate 12, and the roll bearing seat 10 is bolted to the fuselage deck fixing plate 12, allowing the roll bearing seat 10 to move back and forth on the fuselage deck fixing plate 12; the roll shaft 9 is connected to the roll bearing seat 10 via a bearing, providing the platform with roll motion freedom; the pitch axis 8 passes through the through hole of the roll shaft 9 and is fixedly connected to the roll shaft 9. The pitch axis 8 is connected to the pitch bearing seat 7 via a bearing, and the pitch bearing seat 7 is connected to the fork-shaped component 15 via bolts; the lifting inner carbon tube flange 4 is connected to the fork-shaped component 15 via bolts, and the lifting inner carbon tube 3 is connected to the lifting inner carbon tube flange 4 via an interference fit; the yaw locking component 2 is connected to the fork-shaped component 15 via bolts and is used to lock or unlock the yaw degree of freedom; the lifting outer carbon tube 1 and the lifting inner carbon tube 3 are nested together, and the lifting inner carbon tube 3 can slide up and down in the lifting outer carbon tube 1, thereby driving the entire test platform to achieve lifting and lowering movement.

[0039] In practical applications, the fuselage fixing U-shaped component 5 and the fuselage deck fixing plate 12 fix the fuselage in the vertical direction, respectively. The roll shaft 9 provides the aircraft's roll motion, and the bolts on the roll bearing seat 10 can lock the roll shaft 9, controlling the locking and unlocking of the roll degree of freedom. The pitch shaft 8 passes through the through hole on the roll shaft 9, and the bolts on the roll shaft 9 lock the middle flat end face of the pitch shaft 8. This achieves the fixation of the pitch shaft 8. The pitch shaft 8 is connected to the pitch bearing seat 7 through a bearing, providing the test platform with the pitch degree of freedom. The bolts on the pitch bearing seat 7 can lock the pitch shaft 8, controlling the locking and unlocking of the pitch degree of freedom. The lifting outer carbon tube 1 is connected to the lifting inner carbon tube flange 4 via an interference fit. The lifting outer carbon tube 1 covers the lifting inner carbon tube 3, allowing the inner carbon tube 3 to rotate and move up and down within the lifting outer carbon tube 1. This provides the entire test platform with yaw and lifting degrees of freedom. The yaw locking component 2 is connected to the fork-shaped component 15, and its lower end is connected to the yaw limiting component 16. This allows for locking of the yaw degree of freedom without affecting the lifting degree of freedom. When it is necessary to release the yaw degree of freedom, the yaw locking component 2 can be disassembled. In the test mechanism designed in this invention, the locking of each degree of freedom can be achieved using the simplest screw tightening locking design.

[0040] In the specific design, the yaw locking component 2 in the above-mentioned test mechanism is set on the lifting outer carbon tube 1. The middle of the yaw locking component 2 is a circular through hole, and the two ends can be fixed by bolts to adjust the size of the middle circular through hole, so as to achieve fastening on the lifting outer carbon tube 1. The locking platforms on both sides of the yaw locking component 2 have through holes that cooperate with the yaw limiting component 16. The yaw limiting component 16 can be simply set as two lugs. The upper end of the lugs is fixed on the fork-shaped component 15. The lugs are inserted into the through holes of the locking platforms on both sides of the yaw locking component 2 to achieve the limiting during the yaw process.

[0041] Using the test mechanism designed above, a ground-based vehicle-mounted wind test was conducted on a multi-rotor tiltrotor aircraft. The test process included the following steps:

[0042] The first step is to install the aircraft on the ground vehicle-mounted wind test mechanism, and place the test mechanism on a movable platform. In the specific implementation process, the movable platform is not limited to a single form of movement. A simple option such as a vehicle platform can be used to simulate the real outdoor environment. When conducting wind tests, the movable platform can include at least the following forms of movement: downwind movement, upwind movement, and crosswind movement.

[0043] The second step is to adjust the combination of degrees of freedom of the test mechanism according to the test requirements, including at least the lift, yaw, roll and pitch degrees of freedom; the combination of degrees of freedom should include at least the degrees of freedom corresponding to the individual release pitch attitude, the individual roll attitude, the lift-pitch combination attitude, the individual lock yaw attitude, and the fully released state.

[0044] The third step is to conduct a wind test to observe the motion of the aircraft on the test mechanism and obtain the corresponding motion performance. In order to collect test data more accurately and in a timely manner, several sensors can be set on the test mechanism.

[0045] In the second step, the pitch attitude is released individually to observe the aircraft's pitch motion in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of the aircraft control system parameters; the roll attitude is released individually to observe the aircraft's roll motion in the air, obtain the magnitude of the aircraft's roll motion, and guide the aircraft's roll control; the climb-pitch combination attitude is released individually to observe the combined climb and pitch motion form of the aircraft during the tilt transition state in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of the aircraft's transition state control parameters; the yaw attitude is locked individually to observe the aircraft's climb, pitch, and roll motion in the air, obtain the aircraft's climb, pitch, and roll combination motion coordination performance, and guide the adjustment of parameters such as the aircraft's pitch installation angle and initial angle of attack; the fully released state is used to verify the coordination of the aircraft's various attitude motions in free flight.

[0046] In the second step, observing the pitch and climb states of the multi-rotor tiltrotor aircraft separately and locking the roll and yaw attitudes are the core test contents in the adjustment process of the multi-rotor tiltrotor aircraft. This test requirement and the observation of the test phenomena are more conducive to obtaining the response form of the aircraft's climb and pitch attitudes during the transition from multi-rotor to fixed-wing state. The relevant test results can directly guide the adjustment of flight control parameters in the transition state of the flight control system. Traditional ball joint mechanisms with three rotational degrees of freedom combined with one lift degree of freedom cannot meet the requirements for observing the response of one or more combined degrees of freedom interacting with each other. To meet the diverse testing needs of multi-bladed tiltrotors, this mechanism independently separates and redistributes the degrees of freedom, achieving independent control of each degree of freedom. In particular, the cylindrical joint design used in the yaw and lift degree of freedom design naturally couples the yaw rotational degree of freedom and the lift translational degree of freedom, making independent control difficult. This solution uses a fork-shaped component mechanism to retain the lift degree of freedom while locking the yaw rotational degree of freedom, and uses an internal tube rope locking lift design to retain the yaw degree of freedom while locking the lift translational degree of freedom, achieving decoupling of the rotational and translational degrees of freedom of the cylindrical joint.

[0047] In addition, in traditional test mechanisms, the intersection points of the motion axes of each degree of freedom on most test platforms do not coincide with the center of gravity of the aircraft. For example, in ball joint mechanisms, the intersection points of the rotation axes of each degree of freedom are mostly outside the center of gravity of the aircraft, far away from it. This leads to a significant difference between the attitude response state of the aircraft during the test and the actual attitude response of the aircraft, failing to fully and realistically represent the actual response state of the aircraft. To solve this problem, this design adopts a suspended fuselage-type structure, which makes the intersection points of the motion axes of the test mechanism basically coincide with the center of gravity of the aircraft. The response state of the aircraft on the test mechanism is closer to the actual response state of the aircraft, providing a response form that is closer to the actual flight state for adjusting the flight control system parameters of multi-rotor tiltrotor aircraft in various states, and better guiding the adjustment of flight control system parameters.

[0048] As described above, exemplary embodiments of the present invention have been described in detail with reference to the accompanying drawings. It should be understood that these specific details are not intended to limit the scope of the invention. Equivalent or similar changes may be made to the structure and features of the exemplary embodiments without departing from the spirit and scope of the invention, and these changes will also fall within the scope of protection defined by the appended claims.

Claims

1. A ground-based vehicle-mounted wind-blowing test mechanism for a multi-rotor tiltrotor aircraft, characterized in that, The test mechanism includes: a first lift tube, a yaw locking component, a second lift tube, a fixed flange, a fixed U-shaped component, a pitch bearing housing, a pitch shaft, a roll shaft, a roll bearing housing, a bearing housing base plate, a fuselage deck fixing plate, a fork-shaped component, and a yaw limiting component. The second lifting tube is placed inside the first lifting tube, and the second lifting tube can slide up and down in the first lifting tube, thereby driving the entire test platform to achieve lifting movement; The fixed U-shaped component is connected to the fuselage deck fixing plate to fix and lock the aircraft fuselage; the bearing seat base plate is connected to the fuselage deck fixing plate; the roll bearing seat is connected to the fuselage deck fixing plate and can move back and forth on the fuselage deck fixing plate; the roll shaft is connected to the roll bearing seat through a bearing to provide the platform with roll motion freedom. The pitch axis passes through the through hole of the roll axis and is fixedly connected to the roll axis. The pitch axis is connected to the pitch bearing seat through a bearing, and the pitch bearing seat is connected to the fork-shaped component. The fixed flange is connected to the fork-shaped component, and the second lifting pipe is connected to the fixed flange by an interference fit; The yaw locking component cooperates with the yaw limiting component set on the first elevator tube to lock or unlock the yaw degree of freedom.

2. The ground-based vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft as described in claim 1, characterized in that, The first lifting tube is a lifting outer carbon tube, and the second lifting tube is a lifting inner carbon tube; the lifting outer carbon tube and the lifting inner carbon tube are nested together, and the lifting inner carbon tube can slide up and down in the lifting outer carbon tube, thereby driving the entire test platform to achieve lifting movement.

3. The ground-based vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft as described in claim 1, characterized in that, The fork-shaped component is located on the outside of the fuselage and adopts a wraparound design.

4. The ground-based vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft as described in claim 3, characterized in that, The lower end of the fork-shaped component is provided with a vertically arranged long lug as a yaw locking component, and the long lug engages with the through hole on the yaw limiting component.

5. The ground-based vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft as described in claim 1, characterized in that, The fixed U-shaped component also contains a fuselage outline support block.

6. The ground-based vehicle-mounted wind-blowing test mechanism for multi-rotor tiltrotor aircraft as described in claim 1, characterized in that, The test mechanism also includes an upper pitch limit plate and a lower pitch limit plate. The upper pitch limit plate is fixed to the lower end face of the fixed U-shaped part of the fuselage; the lower pitch limit plate is fixed to the fixed flange.

7. A ground-based vehicle-mounted wind-blowing test method for multi-rotor tiltrotor aircraft, characterized in that, The experimental method includes the following steps: Step S1: Install the aircraft on the ground vehicle-mounted wind test mechanism as described in any one of claims 1-6, and place the test mechanism on a movable platform. Step S2: Adjust the combination of degrees of freedom of the test mechanism according to the test requirements; Step S3: Conduct a wind test, observe the motion state of the aircraft on the test mechanism, and obtain the corresponding motion performance.

8. The ground-based vehicle-mounted wind-blowing test method for a multi-rotor tiltrotor aircraft as described in claim 7, characterized in that, In step S2, the degree of freedom combination forms include at least the degree of freedom forms corresponding to the individual release pitch attitude, individual roll attitude, combined heave and pitch attitude, individual lock yaw attitude, and all release states. The separate release of pitch attitude is used to observe the aircraft's pitch motion in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of aircraft control system parameters; the separate release of roll attitude is used to observe the aircraft's roll motion in the air, obtain the magnitude of the aircraft's roll motion, and guide the aircraft's roll control; the combined climb and pitch attitude is used to observe the combined climb and pitch motion of the aircraft during the tilt transition state in the air, obtain the aircraft's pitch motion speed and slowness performance, and guide the adjustment of aircraft transition state control parameters; the separate lock of yaw attitude is used to observe the aircraft's climb, pitch, and roll motion in the air, obtain the aircraft's combined climb, pitch, and roll motion coordination performance, and guide the adjustment of aircraft pitch installation angle and initial angle of attack parameters; the fully released state is used to verify the coordination of the aircraft's various attitude motions in free flight.

9. The ground-based vehicle-mounted wind-blowing test method for a multi-rotor tiltrotor aircraft as described in claim 7, characterized in that, When conducting a wind test, the motion platform may include at least the following motion modes: downwind motion, upwind motion, and crosswind motion.

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