A four-bar linkage for attitude control of a flight platform

Abstract

The present invention relates to a four-bar linkage for attitude control of a flight platform, which is installed on the flight platform, and the four-bar linkage includes a support frame, a steering gear is installed on the top of the support frame, the steering gear is connected to an external power supply, the steering gear is connected to a steering gear arm, the steering gear arm is connected to a transmission rod, the transmission rod is connected to an ear piece, the ear piece is connected to a fixed frame, a turbojet engine is installed on the fixed frame, and the fixed frame is connected to a bearing installed on the support frame. Compared with the prior art, the present invention can effectively improve the attitude control accuracy of the flight platform and reduce the construction cost.

Description

Technical Field

[0001] The present invention relates to the technical field of flight platform attitude control, and in particular to a four-bar linkage mechanism used for flight platform attitude control. Background Art

[0002] Only with attitude control can the aircraft move along a predetermined trajectory in the air. Attitude control requires controlling the torque that changes the aircraft's attitude angle. At present, the aircraft's attitude control methods mainly include: aerodynamic control, thrust vector control, jet reaction control, flywheel control, magnetic torque control, variable center of mass control and composite control. Among them, aerodynamic control is based on the principle of relativity of motion and the basic laws of gas flow. It uses aerodynamics to control the torque balance of each spatial dimension, thereby achieving the purpose of attitude stability. However, under low speed and low pressure conditions, aerodynamic control methods cannot achieve attitude control.

[0003] Compared with aerodynamic control, thrust vector control achieves the purpose of aircraft attitude control by changing the direction of the airflow exhausted by the engine. However, the existing thrust vector control cannot guarantee control accuracy and has a high construction cost. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a four-bar linkage for flight platform attitude control, which can improve attitude control accuracy and reduce construction costs.

[0005] The objective of the present invention can be achieved through the following technical scheme: a four-bar linkage for attitude control of a flight platform, installed on the flight platform, the four-bar linkage comprising a support frame, a servo mounted on the top of the support frame, the servo connected to an external power supply, the servo connected to a servo arm, the servo arm connected to a transmission rod, the transmission rod connected to an ear piece, the ear piece connected to a fixing frame, a turbojet engine mounted on the fixing frame, the fixing frame connected to a bearing mounted on the support frame.

[0006] Furthermore, the bearing is embedded and installed in the center position of the support frame.

[0007] Furthermore, the end cover of the bearing is connected to the support frame by bolts.

[0008] Furthermore, the turbojet engine upper fastening sleeve is provided with a fixing ring, and the fixing ring is mounted on the fixing frame by bolts.

[0009] Furthermore, the ear piece is connected to the fixing frame by welding.

[0010] Furthermore, the fixing frame and the bearing are in a transition fit connection relationship.

[0011] Furthermore, the steering gear is connected to the steering gear arm via bolts.

[0012] Furthermore, the steering gear arm is connected to the transmission rod through bolts.

[0013] Furthermore, the transmission rod is connected to the ear piece through bolts.

[0014] Furthermore, the bearing is specifically a deep groove ball bearing.

[0015] Compared with the prior art, the present invention provides a servo and remotely controls the servo to control the servo arm to drive the transmission rod, thereby forming a four-bar linkage, thereby improving the accuracy of attitude control of the flight platform and ensuring the effective length and angular range of the four-bar linkage.

[0016] The present invention sets the fixing frame and the bearing as a transition fit connection. In addition, a deep groove ball bearing is used, thereby effectively solving the jet steering problem of the turbojet engine. The turbojet engine can rotate freely while ensuring a tight connection, thereby reducing thrust resistance and realizing thrust vector control.

[0017] The present invention adopts the jet of the turbojet engine as the thrust vector source, and no longer needs to rely on other structures for directional guidance. It has a simple structure and can effectively reduce processing costs. Even if some parts are damaged or worn, they can be easily replaced, reducing unnecessary economic costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0019] Figure 2 It is a schematic diagram of the main structure of the present invention;

[0020] Figure 3 It is a side view structural schematic diagram of the present invention;

[0021] Figure 4 Schematic diagram of the motion trajectory of the four-bar linkage in the embodiment;

[0022] Explanation of the markings in the figure: 1. turbojet engine, 2. fixing ring, 3. fixing frame, 4. servo, 5. servo arm, 6. transmission rod, 7. ear piece, 8. bearing, 9. end cover, 10. support frame. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Example

[0025] like Figure 1 to Figure 3As shown, a four-bar linkage for attitude control of a flight platform is installed on the flight platform. In this embodiment, four four-bar linkages distributed in a rectangular shape are installed on the flight platform.

[0026] Among them, the four-bar linkage includes a support frame 10, a steering gear 4 is installed on the top of the support frame 10, the steering gear 4 is connected to an external power supply, the steering gear 4 is connected to a steering gear arm 5, the steering gear arm 5 is connected to a transmission rod 6, the transmission rod 6 is connected to an ear piece 7, the ear piece 7 is connected to a fixing frame 3, a turbojet engine 1 is installed on the fixing frame 3, and the fixing frame 3 is connected to a bearing 8 installed on the support frame 10.

[0027] In this embodiment, the steering gear 4 uses a 60kg steering gear, the support frame 10 is a Y-shaped support frame, and a through hole is reserved at the center of the support frame 10 for embedding and installing the bearing 8, and the end cover 9 of the bearing 8 is connected to the support frame 10 by bolts. In order to solve the jet steering problem of the turbojet engine 1, the bearing 8 uses a light open series of deep groove ball bearings (16012 bearings are used in this embodiment), and a transition fit is used between the fixing frame 3 of the turbojet engine 1 and the bearing 8, thereby ensuring a tight connection and not hindering the rotation continuity of the turbojet engine 1.

[0028] In addition, a fixing ring 2 is provided on the fastening sleeve of the turbojet engine 1, the fixing ring 2 is mounted on the fixing frame 3 by bolts, and the ear piece 7 is connected to the fixing frame 3 by welding;

[0029] The steering gear 4 is connected to the steering gear arm 5 through bolts, the steering gear 5 arm is connected to the transmission rod 6 through bolts, and the transmission rod 6 is connected to the ear piece 7 through bolts.

[0030] In this technical solution, the steering gear 4 provides power for the entire four-bar linkage to achieve the effect of four-bar cyclic reciprocating motion and realize vector control of the flight platform.

[0031] In this embodiment, the specific motion trajectory of the four-bar linkage is as follows: Figure 4 As shown in the figure, the solid small circle is the motion trajectory of the outer periphery of the steering gear arm 5, the solid large circle is the motion trajectory of the outer end of the ear piece 7, and the dotted circle is a schematic diagram of the outer wall of the fixing frame 3. The specific working process of this embodiment is:

[0032] Step 1: Turn on the external power supply, the servo 4 is powered, press the reset button of the remote control, and the servo arm 5 moves to point A. At this time, the ear piece 7 is linked to point B. The transmission rod 6 is between points A and B. At this time, the turbojet engine 1 is in a vertical downward state, that is, in a vertical state. Subsequent power is input to enable the flight platform to obtain sufficient lift (generated by the reverse jet of the turbojet engine 1).

[0033] Step 2: Clockwise rotation: When the flight platform flies to the required height, the movement direction of the steering gear arm 5 is changed, and the steering gear arm 5 gradually moves from point A to point C along the trajectory, driving the linkage rod 6 to move, and the ear piece 7 gradually moves from point B to point D along the trajectory, and the turbojet engine 1 rotates synchronously with the direction of the ear piece 7;

[0034] When rotating counterclockwise: the steering gear arm 5 moves gradually from point A to point E along the trajectory, driving the linkage rod 6 to move, the ear piece 7 moves gradually from point B to point F along the trajectory, and the turbojet engine 1 rotates synchronously with the direction of the ear piece 7;

[0035] When the flying platform is hovering, the steering gear 4 on the left side rotates clockwise, and the steering gear 4 on the right side rotates counterclockwise, so that the turbojet engines 1 on both sides are in a relatively horizontal position.

[0036] Step 3: Clockwise rotation: When the steering gear arm 5 moves to point C, the turbojet engine 1 moves to point D along with the connecting ear piece 7. At this time, the transmission rod 6 is between points C and D, and this position is the end point of clockwise rotation;

[0037] Counterclockwise rotation: when the steering gear arm 5 moves to point E, the turbojet engine 1 moves to point F along with the connecting ear piece 7. At this time, the transmission rod 6 is between E and F, and this position is the end point of counterclockwise rotation;

[0038] The steering gear 4 is controlled to make the steering gear arm 5 rotate clockwise, and at the same time the turbojet engine 1 rotates clockwise, and the overall power of the flight platform changes from the first quadrant to the fourth quadrant, thereby forming an oblique projection motion, achieving an accelerated ascent and dive state;

[0039] The theoretical maximum rotation angle of the steering gear arm 5 is 180 degrees, and the actual maximum rotation angle required is 153 degrees, with 27 degrees of surplus rotation. The maximum length of the transmission rod 6 is required to be 78.70 mm, and the minimum length is required to be 75.16 mm. Therefore, 76 mm is selected in this embodiment to meet the required rotation angle.

[0040] Step 4: Press the reset button of the remote control to move the servo arm 5 and drive the turbojet engine 1 to move. The servo arm 5 moves to point A. At this time, the ear piece 7 is linked to point B, so that the turbojet engine 1 is in a vertical downward state. At this time, the turbojet engine 1 is in a vertical state, reducing the power input, and finally achieving the purpose of smooth vertical landing.

[0041] In summary, the technical solution uses the servo to accurately control the servo arm to form a four-bar linkage, which has ultra-high precision in the attitude control of the flight platform. In this embodiment, the effective length of the four-bar linkage is 76 mm, and the turning angle can reach ±90°, which will not interfere with the movement of the nozzle.

[0042] The structural components of this technical solution are simple to process and economical: the turbojet engine jet is directly used as the thrust vector source, and there is no need to use other structures for directional guidance, which reduces processing costs. In addition, some parts can be easily replaced when they are damaged or worn, reducing unnecessary economic costs.

[0043] This technical solution has wide applicability: the four-bar linkage is not only suitable for flying platforms, but can also be used as a power drive structure for underwater detection robots when equipped with a waterproof coating. It has high speed and good pressure resistance, and can handle and avoid emergencies in a timely manner. In addition, the structure is compact and can be used for most industrial processing.

Claims

1. A four-bar linkage for attitude control of a flight platform, mounted on the flight platform, characterized in that: The four-bar linkage comprises a support frame (10), a steering gear (4) is installed on the top of the support frame (10), the steering gear (4) is connected to an external power supply, the steering gear (4) is connected to a steering gear arm (5), the steering gear arm (5) is connected to a transmission rod (6), the transmission rod (6) is connected to an ear piece (7), the ear piece (7) is connected to a fixing frame (3), a turbojet engine (1) is installed on the fixing frame (3), and the fixing frame (3) is connected to a bearing (8) installed on the support frame (10); The motion trajectory of the four-bar linkage includes the motion trajectory of the periphery of the steering gear arm (5) and the motion trajectory of the outer end of the ear piece (7). The specific working process is as follows: Step 1: Turn on the external power supply, the steering gear (4) is powered, and in the reset state, the steering gear arm (5) moves to point A, at which time the ear piece (7) is linked to point B, and the transmission rod (6) is between points A and B. At this time, the turbojet engine (1) is in a vertical downward state, that is, in a vertical state, and subsequent power is input, so that the flight platform obtains the lift generated by the reverse jet of the turbojet engine (1); Step 2: When rotating clockwise: When the flight platform flies to the required height, the movement direction of the steering gear arm (5) is changed, and the steering gear arm (5) moves gradually from point A to point C along the trajectory, driving the linkage rod (6) to move, and the ear piece (7) moves gradually from point B to point D along the trajectory, and the turbojet engine (1) rotates synchronously with the direction of the ear piece (7); When rotating counterclockwise: the steering gear arm (5) moves gradually from point A to point E along the trajectory, driving the linkage rod (6) to move, the ear piece (7) moves gradually from point B to point F along the trajectory, and the turbojet engine (1) rotates synchronously with the direction of the ear piece (7); When the flying platform is hovering, the steering gear (4) on the left side rotates clockwise, and the steering gear (4) on the right side rotates counterclockwise, so that the turbojet engines (1) on both sides are in a relatively horizontal position; Step 3: Clockwise rotation: When the steering gear arm (5) moves to point C, the turbojet engine (1) moves to point D along with the connecting ear piece (7). At this time, the transmission rod (6) is between points C and D, and this position is the end point of clockwise rotation; Counterclockwise rotation: when the steering gear arm (5) moves to point E, the turbojet engine (1) moves to point F along with the connecting ear piece (7). At this time, the transmission rod (6) is located between E and F, and this position is the end point of counterclockwise rotation; Controlling the steering gear (4) so ​​that the steering gear arm (5) rotates clockwise, and at the same time the turbojet engine (1) rotates clockwise, the overall power of the flight platform changes from the first quadrant to the fourth quadrant, thereby forming an oblique projection motion, achieving an accelerated ascent and dive state; The theoretical maximum rotation angle of the steering gear arm (5) is 180 degrees, and the actual maximum rotation angle required is 153 degrees, with a surplus of 27 degrees. The maximum length of the transmission rod (6) is required to be 78.70 mm, and the minimum length is required to be 75.16 mm; Step 4: Reset again, so that the steering gear arm (5) moves, driving the turbojet engine (1) to move, the steering gear arm (5) moves to point A, at this time the ear piece (7) is linked to point B, so that the turbojet engine (1) is in a vertical downward state, at this time the turbojet engine (1) is in a vertical state, reducing the power input, and finally achieving the purpose of stable vertical landing; The effective length of the four-bar linkage is 76 mm, and the rotation angle is ±90°, which will not interfere with the movement of the nozzle.

2. A four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The bearing (8) is embedded and installed at the center position of the support frame (10).

3. A four-bar linkage for flight platform attitude control according to claim 2, characterized in that: The end cover (9) of the bearing (8) is connected to the support frame (10) via bolts.

4. A four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The turbojet engine (1) has a fastening sleeve provided with a fixing ring (2), and the fixing ring (2) is mounted on a fixing frame (3) by means of bolts.

5. The four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The ear piece (7) is connected to the fixing frame (3) by welding.

6. A four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The fixing frame (3) and the bearing (8) are in a transition fit connection relationship.

7. The four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The steering gear (4) is connected to the steering gear arm (5) via bolts.

8. The four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The steering gear arm (5) is connected to the transmission rod (6) via bolts.

9. The four-bar linkage for flight platform attitude control according to claim 1, characterized in that: The transmission rod (6) is connected to the ear piece (7) via bolts.

10. A four-bar linkage for attitude control of a flight platform according to any one of claims 1 to 9, characterized in that: The bearing (8) is specifically a deep groove ball bearing (8).

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