阅读说明：本技术 用于旋翼类无人飞行器飞行动力学建模的地面测试系统及方法 (Ground test system and method for rotor type unmanned aerial vehicle flight dynamics modeling ) 是由 于永志 张玘 秦国军 胡政 王珉 谭钢 李俊杰 周杰达 周泽蕴 于 2021-11-19 设计创作，主要内容包括：本发明公开了一种用于旋翼类无人飞行器飞行动力学建模的地面测试系统及方法,包括风洞装置、飞行器试验装置、控制装置和测试装置,飞行器试验装置安装在风洞装置内,控制装置和测试装置均与风洞装置和飞行器试验装置连接,飞行器试验装置包括旋翼试验台和安装在旋翼试验台上用于安装飞行器的飞行器适配安装座。本发明的测试系统不需要对被测旋翼无人飞行器的飞行原理进行太多的机理分析,而是通过准确、可控地模拟被测旋翼无人飞行器在真实应用场景的飞行工况,获得被测旋翼无人飞行器在各种模拟真实应用场景下的飞行参数,并利用获得的试验数据与操控参数建立旋翼类无人飞行器的飞行动力学模型。(The invention discloses a ground test system and a ground test method for rotor wing type unmanned aerial vehicle flight dynamics modeling, and the ground test system comprises a wind tunnel device, an aircraft test device, a control device and a test device, wherein the aircraft test device is installed in the wind tunnel device, the control device and the test device are both connected with the wind tunnel device and the aircraft test device, and the aircraft test device comprises a rotor wing test bed and an aircraft adaptive installation seat which is installed on the rotor wing test bed and used for installing an aircraft. The testing system does not need to carry out too much mechanism analysis on the flight principle of the tested rotor unmanned aerial vehicle, obtains flight parameters of the tested rotor unmanned aerial vehicle in various simulated real application scenes by accurately and controllably simulating the flight working conditions of the tested rotor unmanned aerial vehicle in real application scenes, and establishes a flight dynamics model of the rotor unmanned aerial vehicle by using the obtained test data and the control parameters.)

1. The utility model provides a ground test system for rotor type unmanned vehicles flight dynamics modeling which characterized in that, includes wind-tunnel device, aircraft test device (7), controlling means and testing arrangement, install aircraft test device (7) in the wind-tunnel device, controlling means and testing arrangement all with wind-tunnel device and aircraft test device (7) are connected, aircraft test device (7) include rotor test bench (8) and install be used for installing aircraft adaptation mount pad (9) by survey rotor unmanned vehicles (10) on rotor test bench (8).

2. The ground test system for modeling flight dynamics of a rotor type unmanned aerial vehicle according to claim 1, wherein the wind tunnel device comprises a fan variable frequency controller (1), an axial flow fan (2), a convergence section (3), a test section (4) and an expansion section (5), the fan variable frequency controller (1) is connected with the axial flow fan (2), the convergence section (3) and the expansion section (5) are respectively installed at the head end and the tail end of the test section (4), the axial flow fan (2) is installed at the input end of the convergence section (3), and the aircraft test device (7) is installed in the test section (4).

3. The ground test system for rotor type unmanned aerial vehicle flight dynamics modeling according to claim 2, characterized in that an air velocity tube (19), a six-component sensor (23) and a two-axis vector control mechanism (20) are installed on the upper portion of the rotor test stand (8), the six-component sensor (23) is installed on the top of the two-axis vector control mechanism (20), and the aircraft adapter mount (9) is installed on the top of the six-component sensor (23).

4. The ground test system for modeling flight dynamics of a rotor-type unmanned aerial vehicle according to claim 3, wherein the two-axis vector control mechanism (20) comprises a base support (24), a transverse axis drive frame (25), a first pull rod (26), a longitudinal axis drive frame (27), a second pull rod (29), a first servo steering engine (30) and a second servo steering engine (40), two ends of the transverse axis drive frame (25) are hinged to the upper side of the base support (24), two ends of the longitudinal axis drive frame (27) are hinged to the transverse axis drive frame (25), one end of the second pull rod (29) is hinged to the first servo steering engine (30), the other end of the second pull rod is hinged to the transverse axis drive frame (25), one end of the first pull rod (26) is hinged to the second servo steering engine (40), and the other end of the first pull rod is hinged to the longitudinal axis drive frame (27), the six-component sensor (23) is mounted on the upper side of the longitudinal shaft drive carriage (27).

5. The ground test system for modeling rotor-type unmanned aerial vehicle flight dynamics of claim 4, characterized in that said control means comprises a test system controller (22) mounted on the underside of said longitudinal axis drive carriage (27), said test system controller (22) having MEMS gyroscopes built into it to enable real-time closed-loop adjustment and control of the spatial mounting attitude of the rotor-type unmanned aerial vehicle (10) under test.

6. The ground test system for modeling of rotor type unmanned aerial vehicle flight dynamics of claim 5, characterized in that the test system controller (22) is connected with the wind speed tube (19) and the fan variable frequency controller (1) simultaneously to achieve real-time closed loop regulation and control of simulated wind speed.

7. Ground test system for modeling the flight dynamics of a rotary-wing type unmanned aerial vehicle according to any of claims 2-6, characterized in that said test section (4) is fitted with a honeycomb device (6) close to the input end of said convergent section (3), said aircraft test device (7) being fitted behind said honeycomb device (6).

8. The ground test system for rotor type unmanned aerial vehicle flight dynamics modeling according to any one of claims 3-6, characterized in that a stand column (13), a bottom plate (14), a stand column connection assembly (15), a diagonal rib assembly (17) and a adapter (18) are installed at the lower portion of the rotor test stand (8), the stand column (13) is fixed on the bottom plate (14) through the stand column connection assembly (15), the diagonal rib assembly (17) is arranged along the circumferential direction of the stand column (13), one end of the diagonal rib assembly (17) is fixedly connected with the upper portion of the stand column (13), the other end of the diagonal rib assembly is obliquely fixedly connected with the bottom plate (14), the adapter (18) is installed on the stand column (13), and the two-axis vector control mechanism (20) is installed on the adapter (18).

9. The ground test system for modeling the flight dynamics of a rotary-wing type unmanned aerial vehicle according to claim 8, wherein a heavy duty Frouhorse wheel (11) and a counterweight (12) are mounted to the bottom of the base plate (14).

10. A ground test method of a rotor type unmanned aerial vehicle is characterized by comprising the following steps:

s1, selecting a proper aircraft adaptive installation seat (9) according to the type and the size of the tested rotor unmanned aerial vehicle (10), installing and fixing the aircraft adaptive installation seat (9) on the upper end face of the six-component sensor (23), and then fixing the tested rotor unmanned aerial vehicle (10) on the aircraft adaptive installation seat (9);

s2, connecting the control device and each module and assembly in the testing device, checking and confirming the mechanical connection and electrical connection of the testing system, supplying power to each module and assembly under the normal condition in the checking step, setting the required simulated wind speed and the spatial installation attitude of the tested unmanned aerial vehicle (10), starting the tested unmanned aerial vehicle (10), and giving an operation command according to the test requirement through the control device to enable the tested unmanned aerial vehicle (10) to work as required;

s3, completing the acquisition, processing analysis and storage of test data through a test device, and evaluating the flight power performance and the operation performance of the tested rotor unmanned aerial vehicle (10) simulated in a real application scene;

and S4, taking down the tested rotor unmanned aerial vehicle and closing the power supply of the test system to finish the test process.

Technical Field

The invention relates to the technical field of unmanned aerial vehicles, in particular to a ground test system and method for rotor type unmanned aerial vehicle flight dynamics modeling.

Background

With the development and progress of novel scientific technology, traditional multi-rotor wings such as a four-rotor wing and a six-rotor wing, and unmanned aerial vehicles such as helicopters and tiltrotors are applied in more and more scenes. Modern unmanned vehicles widely adopt flight control systems to improve flight quality, and flight quality becomes one of main design indexes of modern rotor crafts and determines several major factors of flight quality: the stability, maneuverability and maneuverability of the rotor aircraft are always the research subjects of the flight dynamics of the rotor aircraft, and one of the important bases of the stability, maneuverability and maneuverability of the rotor aircraft is a flight dynamics model, and the accuracy of the model directly influences the accuracy of the design and evaluation of the flight quality.

At present, common modeling design methods include a mechanism modeling method based on a physical law and a system identification modeling method based on test data. However, because the pneumatic environment of the rotor type aircraft is complex, the control coupling effect is strong, and the control system is nonlinear, the flight dynamics model constructed completely by the mechanism modeling method has a narrow application range. The system identification modeling method is characterized in that a system mathematical model is established according to input-output data obtained by actual measurement tests, and the method is not required to know detailed physical mechanism details of a research object, only needs to know partial main physical relationships (grey box problem) or even completely does not know the physical significance (black box problem), and exactly makes up for the deficiency of mechanism modeling. Therefore, a complete test system in the field of rotor aircraft flight dynamics modeling based on the system identification method provides a basis for design and optimization of a flight control system of the rotor aircraft, and becomes a problem to be solved urgently.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a ground test system and method for rotor wing type unmanned aerial vehicle flight dynamics modeling.

In order to solve the technical problems, the invention firstly discloses a ground test system for rotor wing type unmanned aerial vehicle flight dynamics modeling, which comprises a wind tunnel device, an aircraft test device, a control device and a test device, wherein the aircraft test device is installed in the wind tunnel device, the control device and the test device are both connected with the wind tunnel device and the aircraft test device, and the aircraft test device comprises a rotor wing test bed and an aircraft adaptive installation seat which is installed on the rotor wing test bed and used for installing an aircraft.

Further, the wind tunnel device comprises a fan variable frequency controller, an axial flow fan, a convergence section, a test section and an expansion section, wherein the fan variable frequency controller is connected with the axial flow fan, the convergence section and the expansion section are respectively installed at the head end and the tail end of the test section, the axial flow fan is installed at the input end of the convergence section, and the aircraft test device is installed in the test section.

Furthermore, an air speed pipe, a six-component sensor and a two-axis vector control mechanism are installed on the upper portion of the rotor wing test bed, the six-component sensor is installed at the top of the two-axis vector control mechanism, and the aircraft adaptive installation seat is installed at the top of the six-component sensor.

Furthermore, the two-axis vector control mechanism comprises a base support, a transverse axis driving frame, a first pull rod, a longitudinal axis driving frame, a second pull rod, a first servo steering engine and a second servo steering engine, wherein two ends of the transverse axis driving frame are hinged to the upper portion of the base support, two ends of the longitudinal axis driving frame are hinged to the transverse axis driving frame, one end of the second pull rod is hinged to the first servo steering engine, the other end of the second pull rod is hinged to the transverse axis driving frame, one end of the first pull rod is hinged to the second servo steering engine, the other end of the first pull rod is hinged to the longitudinal axis driving frame, and the six-component sensor is mounted on the upper side of the longitudinal axis driving frame.

Furthermore, the control device comprises a test system controller installed on the lower side of the longitudinal shaft driving frame, and an MEMS gyroscope is arranged in the test system controller to realize real-time closed-loop adjustment and control of the space installation attitude of the tested rotor unmanned aerial vehicle.

Furthermore, the test system controller is simultaneously connected with the wind speed pipe and the fan variable frequency controller to realize real-time closed-loop regulation and control of the simulated wind speed.

Furthermore, the test section is close to the input end of the convergence section and is provided with a honeycomb device, and the aircraft test device is arranged behind the honeycomb device.

Further, stand, bottom plate, stand coupling assembling, diagonal draw bar subassembly and adapter are installed to the lower part of rotor test bench, the stand passes through stand coupling assembling fixes on the bottom plate, the diagonal draw bar subassembly along stand circumference is laid, just the one end of diagonal draw bar subassembly with the upper portion rigid coupling of stand, the other end slope with the bottom plate rigid coupling, the adapter is installed on the stand, diaxon vector control mechanism installs on the adapter.

Furthermore, the bottom of the bottom plate is provided with a heavy-duty Froude wheel and a counterweight.

Then, the invention discloses a ground test method of a rotor type unmanned aerial vehicle, which comprises the following steps:

s1, selecting a proper aircraft adaptive installation seat according to the type and the size of the tested rotor unmanned aerial vehicle, installing and fixing the aircraft adaptive installation seat on the upper end face of the six-component sensor, and then fixing the tested rotor unmanned aerial vehicle on the aircraft adaptive installation seat;

s2, connecting the control device and each module and assembly in the testing device, checking and confirming the mechanical connection and electrical connection of the testing system, supplying power to each module and assembly under the normal condition in the checking step, setting the required simulated wind speed and the spatial installation attitude of the tested unmanned aerial vehicle, starting the tested unmanned aerial vehicle, giving out an operation command according to the test requirement through the control device, and enabling the tested unmanned aerial vehicle to work as required;

s3, completing acquisition, processing analysis and storage of test data through a test device, and evaluating flight power performance and operation performance of the tested rotor unmanned aerial vehicle simulated in a real application scene;

and S4, taking down the tested rotor unmanned aerial vehicle and closing the power supply of the test system to finish the test process.

Compared with the prior art, the invention has the advantages that:

the testing system does not need to carry out too much mechanism analysis on the flight principle of the tested rotor unmanned aerial vehicle, obtains flight parameters of the tested rotor unmanned aerial vehicle in various simulated real application scenes by accurately and controllably simulating the flight working conditions of the tested rotor unmanned aerial vehicle in real application scenes, and establishes a flight dynamics model of the rotor unmanned aerial vehicle by using the obtained test data and the control parameters. Furthermore, flight parameters obtained through the test of the technical scheme provided by the patent can more truly restore the flight parameters of the tested rotor unmanned aerial vehicle in a real application scene, and then the flight dynamics model of the rotor unmanned aerial vehicle established by using the obtained parameters has higher accuracy and is closer to the real application scene, so that more resources are saved for the iterative optimization design of the flight control system of the rotor unmanned aerial vehicle. Compared with the existing test system which can only be used for one type of test object, the test system can be suitable for rotor type aircrafts such as multiple rotors, helicopters, tilt rotorcraft and the like, and has the advantage of wide application range. In addition, the test system has the advantages of simple and compact structure, small occupied space, strong practicability and simple operation on the whole, and can effectively support and accelerate the system development process of the rotor type unmanned aerial vehicle.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention and do not constitute a limitation of the invention. In the drawings:

FIG. 1 is a schematic front view of a ground test system for modeling the flight dynamics of a rotor type unmanned aerial vehicle according to an embodiment of the disclosure;

FIG. 2 is a schematic cross-sectional view of a ground test system for modeling the flight dynamics of a rotor type unmanned aerial vehicle according to an embodiment of the disclosure;

FIG. 3 is a schematic view of an installation of a tested rotor unmanned aerial vehicle according to an embodiment of the disclosure;

FIG. 4 is a schematic first axis view of a rotor test rig according to an embodiment of the present disclosure;

FIG. 5 is a second axis schematic view of a rotor test rig according to an embodiment of the present disclosure;

FIG. 6 is a schematic view of an installation of a two-axis vector control mechanism according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a six-component sensor installation disclosed in an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a two-axis vector control mechanism according to an embodiment of the present invention;

FIG. 9 is a schematic block diagram of a testing system according to an embodiment of the present invention.

Illustration of the drawings:

1. a fan variable frequency controller; 2. an axial flow fan; 3. a convergence section; 4. a test section; 5. an expansion section; 6. a cellular device; 7. an aircraft testing device; 8. a rotor wing test stand; 9. an aircraft-compliant mount; 10. the tested rotor unmanned aerial vehicle; 11. heavily loading a horse wheel; 12. counterweight weights; 13. a column; 14. a base plate; 15. the upright post connecting assembly; 16. a connecting screw; 17. a cable-stayed assembly; 18. a transfer seat; 19. an air velocity tube; 20. a two-axis vector control mechanism; 21. a socket head cap screw; 22. a test system controller; 23. a six-component sensor; 24. a base support; 25. a transverse shaft drive frame; 26. a first pull rod; 27. a longitudinal shaft drive frame; 28. a rolling bearing; 29. a second pull rod; 30. a first servo steering engine; 31. a first wireless module; 32. testing the computer; 33. a data acquisition and processing module; 34. a second wireless module; 35. a third wireless module; 37. data acquisition HUB; 38. a program-controlled voltage-stabilizing direct-current power supply; 39. a fourth wireless module; 40. and a second servo steering engine.

Detailed Description

In order to facilitate understanding of the invention, the invention will be described more fully and in detail with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below.

As shown in fig. 1, 2 and 5, the embodiment of the invention firstly discloses a ground test system for modeling flight dynamics of a rotor type unmanned aerial vehicle, which comprises an axial flow fan 2, a convergence section 3, a honeycomb device 6, a test section 4, an expansion section 5, a fan variable frequency controller 1 and an aircraft test device 7. The axial flow fan 2, the convergence section 3, the test section 4 and the expansion section 5 are sequentially connected to form a body, the fan frequency conversion controller 1 is arranged on the outer cylindrical surface of the axial flow fan 2, the honeycomb device 6 is arranged at one end, close to the convergence section 3, of the test section 4, and the internal cross-sectional area of the convergence section 3 is gradually reduced from large to be equal to that of the test section 4. The inside equal cross section structure that is of test section 4, aircraft testing arrangement 7 install at the length direction's of test section 4 middle part, have seted up transparent observation hole window in 4 length direction's of test section front and back both sides to observe experimental state, through the rectification of honeycomb ware 6, the air current is laminar flow state in test section 4, can simulate the one-way laminar flow of wind and flow. The cross-section of the expansion section 5 gradually transitions from the junction of the test sections 4 to the exit diameter. The testing system adopts the working mode of blowing by the axial flow fan 2, namely the flowing direction of the airflow in the testing system is the axial flow fan 2 → the convergent section 3 → the honeycomb device 6 → the test section 4 → the divergent section 5 in sequence. The testing system controller 22 can adjust the wind speed output of the axial flow fan 2 through the fan variable frequency controller 1 so as to meet the requirements of different working conditions of a testing test.

As shown in fig. 3 to 7, the aircraft testing apparatus 7 mainly includes a rotor testing stand 8, an aircraft adaptive mount 9, a tested rotor unmanned aerial vehicle 10, a six-component sensor 23, a two-axis vector control mechanism 20, a test system controller 22, an air velocity tube 19, and the like. The whole structure group forming type is laminated from top to bottom, the modules from bottom to top are a rotor wing test bed 8, a two-axis vector control mechanism 20, a test system controller 22, a six-component sensor 23, an aircraft adaptation installation seat 9 and a tested rotor wing unmanned aerial vehicle 10 in sequence, and the modules are connected with one another by using screw standard parts. As shown in fig. 5, the rotor wing test bed 8 adopts a modular design principle, and structural members of the platform body support assembly are all designed by metal profiles, so that the platform body support assembly has good manufacturability and economy. The main component structural members of the rotor wing test bed 8 include a stand column 13, a bottom plate 14, a stand column connecting assembly 15, a diagonal bracing assembly 17, an adapter 18, a counterweight 12, a heavy-duty Frequ wheel 11, a connecting standard member and the like. The upright post connecting assembly 15 and the diagonal member assembly 17 are formed by splicing metal sectional materials, and have good manufacturability and economy. Stand 13 adopts standard section bar processing to form, is the main support component of rotor test bench 8, and stand 13 realizes through the standard component with being connected of rotor test bench 8's bottom plate 14, can realize that the not unidimensional rotor unmanned vehicles 10 of being surveyed that satisfies rotor face apart from the height and the rotor diameter proportional relation on ground through the stand 13 of quick replacement not co-altitude, reaches the wider test range of adaptation. As shown in FIG. 4, the heavy-duty horse wheel 11 is mounted on the lower portion of the bottom plate 14 through the connecting screw 16, levelness adjustment of the test bed can be achieved by adjusting the high-low caster of the heavy-duty horse wheel 11 so as to adapt to various mounting use grounds, effective shock absorption of the test bed on a test system in the working process can be achieved by adjusting the shock absorption caster of the heavy-duty horse wheel 11, and test data obtained by the six-component sensor 23 have higher accuracy. The counterweight 12 is arranged at the bottom of the bottom plate 14, so that the risk of side turning of the table body in the test can be prevented, the test table has a wider torque test range, and the safety design has higher performance. As shown in fig. 6, an adapter 18 is mounted on the top of the column 13, and a two-axis vector control mechanism 20 is mounted on the adapter 18 by a socket head cap screw 21. In addition, the wind speed pipe 19 is also mounted on the adapter 18 in a magnetic attraction manner, and the airflow inlet of the wind speed pipe faces the flowing direction of the simulated wind. As shown in fig. 8, the two-axis vector control mechanism 20 mainly comprises a base support 24, a transverse axis drive frame 25, a longitudinal axis drive frame 27, a first pull rod 26, a second pull rod 29, a first servo steering engine 30, a second servo steering engine 40 and a rolling bearing 28, and has the working principle that a test system controller 22 gives control instructions to the first servo steering engine 30 and the second servo steering engine 40 to drive the transverse axis drive frame 25 and the longitudinal axis drive frame 27 to reach inclination angles at the transverse axis and the longitudinal axis respectively, so that the spatial position attitude of the tested rotor unmanned aerial vehicle 10 is changed, and the condition of simulating actual flight in a real application scene is met. As shown in fig. 7, the six-component sensor 23 and the test system controller 22 are respectively and fixedly installed on the upper and lower surfaces of the longitudinal axis driving frame 27 of the two-axis vector control mechanism 20, and the to-be-tested rotor unmanned aerial vehicle 10 is fixedly connected with the six-component sensor 23 through the vehicle adapting mount 9, so that the six-component sensor 23 can measure the power parameters of the to-be-tested rotor unmanned aerial vehicle 10 in real time. In addition, the test system controller 22 can obtain whether the spatial installation attitude of the tested rotor unmanned aerial vehicle 10 reaches a test set value by using the built-in MEMS gyroscope and perform real-time closed-loop adjustment and control, so that test data obtained by the test system is accurate and controllable; similarly, the fan frequency conversion controller 1 is used for controlling the rotating speed of the axial flow fan 2 and outputting the required wind speed, and simultaneously, the actually detected wind speed is fed back to the test system controller 22 through the wind speed pipe 19, so that the closed-loop control of the simulated wind speed can be realized, and the test result is accurate and controllable.

Then, the invention discloses a ground test system test method for rotor type unmanned aerial vehicle flight dynamics modeling, as shown in fig. 9, the test method of the test system is as follows:

s1, firstly, the operator selects the type and size of the rotor unmanned aerial vehicle 10 to be tested to be the proper aircraft fitting mount 9 and mounts and fixes the aircraft fitting mount on the upper end face of the six-component sensor 23, and then fixes the rotor unmanned aerial vehicle 10 to be tested on the aircraft fitting mount 9.

And S2, carrying out electrical connection between each module and each component of the test system according to a schematic diagram, and then checking and confirming the mechanical connection and the electrical connection condition of the test system. Under the normal condition in the above-mentioned inspection step, turn on programme-controlled steady voltage dc power supply 38 and supply power for data acquisition HUB37 and rotor unmanned vehicles 10 under test in proper order to open fan variable frequency controller 1 and supply power for axial fan 2. The testing computer 32 and the data collecting and processing module 33 are turned on, and two pairs of wireless communication modules (the first wireless module 31 and the third wireless module 35, and the second wireless module 34 and the fourth wireless module 39) are connected. The required simulated wind speed and the spatial installation attitude of the tested rotor unmanned aerial vehicle 10 are set through the data acquisition and processing module 33, the tested rotor unmanned aerial vehicle 10 is started, and the test computer 32 gives an operation instruction according to the test requirement, so that the tested rotor unmanned aerial vehicle 10 works as required.

And S3, the test data are collected, processed, analyzed and stored through the data collection HUB37 and the data collection and processing module 33, and the flight power performance and the operation performance simulated by the tested rotor unmanned aerial vehicle 10 in a real application scene are evaluated.

And S4, finally, loosening the connecting screw 16 of the tested rotor unmanned aerial vehicle 10, taking down the tested rotor unmanned aerial vehicle 10 and turning off the power supply of the test system to finish the test process.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.