CN110861783A - Parallel fuselage course unidirectional constraint method and system - Google Patents

Abstract

The application relates to a parallel fuselage course unidirectional constraint method, which is used for realizing course constraint of a large aircraft fuselage, and comprises the following steps: determining four course restriction points, wherein the course restriction points comprise two frames with stronger bearing capacity in the front/rear airframe and two frames which are symmetrical left and right along the axis of the airframe at the intersection point of the stringer; the front cavities of the uniform load restraining devices on the left side and the right side of the front fuselage are connected with the atmosphere through oil pipes, the front cavities of the uniform load restraining devices on the left side and the right side of the rear fuselage are connected with the atmosphere through oil pipes, and the rear cavities of the uniform load restraining devices on the left side and the right side of the rear fuselage are communicated with the atmosphere; hydraulic oil is injected into a front cavity of the load balancing constraint device of the front fuselage or the rear fuselage to realize the heading displacement constraint and the load monitoring of the airplane. The long lever joint mode of striding the fuselage can be avoided in this application, has shortened the length of connecting piece, has reduced the influence of restraint connecting piece weight to restraint point load.

Description

Parallel fuselage course unidirectional constraint method and system

Technical Field

The application belongs to the technical field of airplane strength tests, and particularly relates to a parallel fuselage course unidirectional constraint method and system.

Background

In the full-size aircraft structural strength verification test, test piece support is the basis and the precondition of test implementation, is not only used for the support during the test preparation period, but also keeps the posture of the test piece stable in the test process and runs through the whole strength test process.

In a structural strength test of a full-size airplane, six degrees of freedom of the full-size airplane are usually constrained by three vertical constraints, one course constraint and two lateral constraints. In a full-size aircraft structural strength test, if the joint of the undercarriage and the aircraft body is used as a key checking part of the test, in order to ensure the checking accuracy of the undercarriage, a course constraint point needs to be arranged on the aircraft body to constrain the course displacement and the balanced course loading error of the aircraft. For a large airplane, the constraint on the course displacement of the airplane body is realized by symmetrically arranging adhesive tapes or other transmission and carrying pieces on the left side and the right side of the frame with stronger bearing capacity of the front airplane body and the rear airplane body. In order to avoid the yaw moment generated by unequal loads on the left side and the right side of the aircraft body in course constraint, equal loads on course constraint points on the left side and the right side of the aircraft body are required, if a left side lever combination mode and a right side lever combination mode are adopted, the connecting piece is long due to the large diameter of the aircraft body, and the weight of the aircraft body has large influence on the calculation of constraint force.

Disclosure of Invention

The application aims to provide a parallel fuselage course unidirectional constraint method and a parallel fuselage course unidirectional constraint system, so as to solve or alleviate at least one problem in the background art.

In one aspect, the technical solution provided by the present application is: a parallel fuselage course unidirectional constraint method is used for realizing course constraint of a large aircraft fuselage, the fuselage comprises a front fuselage and a rear fuselage, and the method comprises the following steps:

determining a heading constraint point, wherein the heading constraint point comprises two frames with stronger bearing capacity in the front fuselage and two frames with stronger bearing capacity in the rear fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the front fuselage and the stringer, and two frames with stronger bearing capacity in the rear fuselage and the stringer, which are symmetrical left and right along the fuselage axis;

the device comprises a front machine body, a rear machine body, a load balancing restraining device, a force sensor, a rear machine body and a control device, wherein the same load balancing restraining device and the force sensor are arranged at each course restraining point, the load balancing restraining device is used for providing restraining force, the force sensor is used for measuring the magnitude of the restraining force, front cavities of the load balancing restraining devices on the left side and the right side of the front machine body are connected through an oil pipe, a rear cavity of the load balancing restraining device is communicated with the atmosphere, front cavities of the load balancing restraining devices on the left side and the right side of the rear machine body are connected through;

each uniform load restraint device is fixed, and hydraulic oil is injected into a front cavity of the uniform load restraint device of the front fuselage or the rear fuselage to realize course displacement restraint and load monitoring of the airplane.

In the method of the present application, the restraining forces provided by the load balancing restraining devices on the left and right sides of the front fuselage are respectively:

F_{front L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀

F_{Front R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁

In the formula, F_{Front L}For the measurement of the force cell on the left side of the front fuselage, F_{Front R}Is the measured value of the force measuring sensor on the right side of the front machine body, D is the diameter of the cylinder body, D is the diameter of the piston rod, f₀And f₁For the friction force between the piston rod and the cylinder of the load balancing restraining device, the load balancing restraining devices on the left and right sides are the same, so f₀＝f₁；

Thus F_{Front L}＝F_{Front R}Namely, the loads of the left and right side loading restraining devices of the front machine body are equal.

In the method of the present application, the restraining forces provided by the load balancing restraining devices on the left and right sides of the rear body are respectively:

F_{rear L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀

F_{Rear R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁

In the formula, F_{Rear L}For the rear fuselage left force cell measurement, F_{Rear R}Measured by a force cell sensor on the right side of the rear machine body, D is the diameter of the cylinder body, D is the diameter of the piston rod, f₀And f₁For the friction force between the piston rod and the cylinder of the load balancing restraining device, the load balancing restraining devices on the left and right sides are the same, so f₀＝f₁；

Thus F_{Rear L}＝F_{Rear R}Namely, the loads of the left and right side load restraining devices of the rear machine body are equal.

In the method of the application, the total load value F of the constraint points of the course of the fuselage_{Navigation device}Comprises the following steps:

F_{navigation device}＝(F_{Front L}+F_{Front R})-(F_{Rear L}+F_{Rear R})。

On the other hand, the technical scheme provided by the application is as follows: a parallel fuselage course unidirectional constraint system is used for any parallel fuselage course unidirectional constraint method, and the system comprises:

the four same load balancing constraint devices and the four force measuring sensors are arranged at a heading constraint point, wherein the heading constraint point comprises two frames with stronger bearing capacity in the front fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the front fuselage and the stringers, and two frames with stronger bearing capacity in the rear fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the rear fuselage and the stringers;

the oil pipe is connected with the front cavity of the uniform-load restraining device on the left side and the right side of the front machine body and the front cavity of the uniform-load restraining device on the left side and the right side of the rear machine body, is connected with the pressure pump and is used for providing pressure.

In the system of the application, the medium used in the load balancing constraint device is non-compressed oil.

In the system of the present application, the deadweight restraint is a hydraulic ram.

The parallel fuselage course unidirectional constraint method and system can avoid a long lever combination mode of crossing the fuselage, shorten the length of the connecting piece, reduce the influence of the weight of the constraint connecting piece on the load of a constraint point, and are simple to implement and convenient to maintain.

Drawings

In order to more clearly illustrate the technical solutions provided by the present application, the following briefly introduces the accompanying drawings. It is to be expressly understood that the drawings described below are only illustrative of some embodiments of the invention.

FIG. 1 is a schematic view of a parallel fuselage heading unidirectional constraint method of the present application.

FIG. 2 is a schematic view of the installation position of the parallel fuselage course unidirectional constraint method of the present application.

FIG. 3 is a structural diagram of a parallel fuselage heading unidirectional constraint system of the present application.

Description of the labeling:

1-fuselage, 11-front fuselage, 12-rear fuselage;

2-load balancing constraint device, 21-piston rod, 22-cylinder, 221-front cavity, 222-rear cavity and 23-load cell.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application.

As shown in fig. 1, in order to solve the problem that in the prior art, a large-sized aircraft needs to fix the heading of a fuselage in a landing gear test, and a fixing device has a large self weight, the application proposes a parallel fuselage heading constraint method which can be used in a full-sized aircraft structural strength test, and the method comprises the following steps;

and S1, determining heading constraint points, wherein the heading constraint points are located at four positions, and the heading constraint points comprise two points which are symmetrical left and right along the axis of the fuselage at the intersection point of the frame with stronger bearing capacity in the front fuselage and the stringer, and two points which are symmetrical left and right along the axis of the fuselage at the intersection point of the frame with stronger bearing capacity in the rear fuselage and the stringer.

S2, arranging the same load balancing restraining devices and force measuring sensors at each course restraining point, wherein the load balancing restraining devices are used for providing restraining force, the force measuring sensors are used for measuring the magnitude of the restraining force, front cavities of the load balancing restraining devices on the left side and the right side of the front machine body are connected through oil pipes, a rear cavity of each load balancing restraining device is communicated with the atmosphere, front cavities of the load balancing restraining devices on the left side and the right side of the rear machine body are connected through oil pipes, and a rear cavity of each load balancing restraining device is communicated with the atmosphere.

S3, each uniform load restraining device is fixed on the restraining upright post through a connecting piece, and the heading displacement restraint and the load monitoring of the airplane can be realized by injecting hydraulic oil into a front cavity of the uniform load restraining device of the front airplane body or the rear airplane body.

As shown in fig. 2, the fuselage 1 of the full-size aircraft comprises afront fuselage 11 and arear fuselage 12, two heading constraint points of thefront fuselage 11 are symmetrically arranged at a front fuselage frame, each heading constraint point comprises a uniformload constraint device 2, aload cell 23 and a connectingpiece 4, andfront cavities 221 in the uniformload constraint devices 2 at two sides of the fuselage are communicated through anoil pipe 3.

As shown in FIG. 3, taking the course restriction point of thefront fuselage 11 as an example, the pressure values of thefront cavity 221 of the uniformload restriction device 2 are all P according to the principle of the communicating vessel in the present application₁，P₁The pressure values of theback cavity 222 are P for supplying pressure to the hydraulic pump₀，P₀For the atmospheric pressure value, the left side of thefront body 11 has the same F for the uniformload restraint device 2_{Front L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀For the right side of thefront body 11, the loadbalancing restraint device 2 has F_{Front R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁。

In the formula, F_{Front L}Measuring a feedback value for a force cell on the left side of the front fuselage, F_{Front R}Measuring a feedback value for a force measuring sensor on the right side of the front machine body, D is the diameter of the cylinder body, D is the diameter of the piston rod, f₀And f₁For the friction force between the piston rod and the cylinder of the uniform load restraining device, the structures and the specifications of the uniform load restraining devices on the left side and the right side are completely consistent, so that f₀＝f₁. Thus F_{Front L}＝F_{Front R}I.e. the left and right of the front body 11The loads of the side load balancing restraining devices are equal, and the requirement that the loads on the two sides of the heading of the airplane body are equal is met.

The course constraint point of therear body 12 is the same as that of thefront body 11, and the pressure values of thefront cavity 221 of the uniformload constraint device 2 are P₁，P₁The pressure values of theback cavity 222 are P for supplying pressure to the hydraulic pump₀，P₀The left side of therear body 12 is provided with the equal-load restraint device 2 at the atmospheric pressure value:

F_{front L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀；

The right sideequipartition restraint device 2 for therear body 12 has:

F_{front R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁。

In the formula, F_{Rear L}Measuring a feedback value for a rear fuselage left force cell, F_{Rear R}Measuring a feedback value for a force measuring sensor at the right side of the rear machine body, wherein D is the diameter of the cylinder body, D is the diameter of the piston rod, and f₀And f₁For the friction force between the piston rod and the cylinder of the uniform load restraining device, the structures and the specifications of the uniform load restraining devices on the left side and the right side are completely consistent, so that f₀＝f₁. Thus F_{Rear L}＝F_{Rear R}Namely, the loads of the load balancing restraining devices on the left side and the right side of therear fuselage 11 are equal, and the requirement that the loads on the two sides of the heading of the fuselage are equal is met.

Finally, the total load value F of the aircraft body course constraint point_{Navigation device}Is F_{Navigation device}＝(F_{Front L}+F_{Front R})-(F_{Rear L}+F_{Rear R})。

The uniform load restraining device in the application uses hydraulic oil, and the heading displacement of the machine body can be kept unchanged in the test due to the approximate incompressibility of the hydraulic oil. In the test process, the load value of the heading constraint point of the airplane body can be obtained through the formula, and meanwhile, the feedback value of the force measuring sensor of each constraint point is monitored in real time. In a full-size airplane structural strength test, when loads of other parts are applied and a fuselage tends to move backwards, the pressure value of a front cavity of a uniform load restraining device of a front fuselage course restraining point is increased, the load is increased, the pressure value of the front cavity of the uniform load restraining device of a rear fuselage course restraining point is reduced, the load is reduced, and the reverse is true.

Correspondingly, the present application further provides a parallel fuselage course unidirectional constraint system, which can be used in any one of the parallel fuselage course unidirectional constraint methods described above, and as shown in fig. 2 and 3, the system of the present application includes:

the four same load-sharing restraining devices 2 and the fourforce measuring sensors 23 are arranged on heading restraining points, wherein the heading restraining points comprise two frames with stronger bearing capacity in thefront fuselage 11 and two frames with stronger bearing capacity in therear fuselage 12, which are bilaterally symmetrical along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in thefront fuselage 11 and the stringers, and two frames with stronger bearing capacity in therear fuselage 12 and the stringers, which are bilaterally symmetrical along the fuselage axis; theoil pipe 3, theoil pipe 3 connects thefront cavity 221 of the uniformload restraining device 2 on the left and right sides of thefront body 11 and thefront cavity 221 of the uniformload restraining device 2 on the left and right sides of therear body 11, and is connected to the pressure pump for providing pressure. Each of the loadbalancing constraint devices 2 includes apiston rod 21 and acylinder 22, thepiston rod 21 is disposed in thecylinder 22 to divide the interior of thecylinder 22 into afront cavity 221 and arear cavity 222 which are not communicated with each other, thefront cavity 221 is connected with anoil pipe 3, and thepiston rod 21 can move by injecting hydraulic oil into thefront cavity 221 through theoil pipe 3.

In an embodiment of the present application, thedeadweight restraint 2 may be a hydraulic ram.

In the system of the application, the medium used in the load balancing constraint device is non-compressed oil.

The parallel fuselage course unidirectional constraint method and system can avoid a long lever combination mode of crossing the fuselage, shorten the length of the connecting piece, reduce the influence of the weight of the constraint connecting piece on the load of a constraint point, and are simple to implement and convenient to maintain.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (7)

1. A parallel fuselage course unidirectional constraint method is used for realizing course constraint of a large aircraft fuselage, the fuselage comprises a front fuselage and a rear fuselage, and the method is characterized by comprising the following steps:

determining a heading constraint point, wherein the heading constraint point comprises two frames with stronger bearing capacity in the front fuselage and two frames with stronger bearing capacity in the rear fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the front fuselage and the stringer, and two frames with stronger bearing capacity in the rear fuselage and the stringer, which are symmetrical left and right along the fuselage axis;

the device comprises a front machine body, a rear machine body, a load balancing restraining device, a force sensor, a rear machine body and a control device, wherein the same load balancing restraining device and the force sensor are arranged at each course restraining point, the load balancing restraining device is used for providing restraining force, the force sensor is used for measuring the magnitude of the restraining force, front cavities of the load balancing restraining devices on the left side and the right side of the front machine body are connected through an oil pipe, a rear cavity of the load balancing restraining device is communicated with the atmosphere, front cavities of the load balancing restraining devices on the left side and the right side of the rear machine body are connected through;

each uniform load restraint device is fixed, and hydraulic oil is injected into a front cavity of the uniform load restraint device of the front fuselage or the rear fuselage to realize course displacement restraint and load monitoring of the airplane.

2. The parallel fuselage course unidirectional constraint method of claim 1, characterized in that the constraint forces provided by the load balancing constraint devices on the left and right sides of the front fuselage are respectively:

F_{front L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀

F_{Front R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁

In the formula, F_{Front L}For the measurement of the force cell on the left side of the front fuselage, F_{Front R}For force-measuring sensor on right side of front bodyMeasured values of the device, D is the diameter of the cylinder, D is the diameter of the piston rod, f₀And f₁For the friction force between the piston rod and the cylinder of the load balancing restraining device, the load balancing restraining devices on the left and right sides are the same, so f₀＝f₁；

Thus F_{Front L}＝F_{Front R}Namely, the loads of the left and right side loading restraining devices of the front machine body are equal.

3. The parallel fuselage course unidirectional constraint method of claim 1, characterized in that the constraint forces provided by the load balancing constraint devices on the left and right sides of the rear fuselage are respectively:

F_{rear L}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₀

F_{Rear R}＝P₁×π(D²-d²)/4-P₀×πD²/4-f₁

In the formula, F_{Rear L}For the rear fuselage left force cell measurement, F_{Rear R}Measured by a force cell sensor on the right side of the rear machine body, D is the diameter of the cylinder body, D is the diameter of the piston rod, f₀And f₁For the friction force between the piston rod and the cylinder of the load balancing restraining device, the load balancing restraining devices on the left and right sides are the same, so f₀＝f₁；

Thus F_{Rear L}＝F_{Rear R}Namely, the loads of the left and right side load restraining devices of the rear machine body are equal.

4. The parallel type fuselage heading unidirectional constraint method of claim 2 or 3, characterized in that the total load value F of the fuselage heading constraint points_{Navigation device}Comprises the following steps:

F_{navigation device}＝(F_{Front L}+F_{Front R})-(F_{Rear L}+F_{Rear R})。

5. A parallel fuselage heading unidirectional constraint system, which is used for the parallel fuselage heading unidirectional constraint method according to any one of claims 1 to 4, and is characterized in that the system comprises:

the four same load balancing constraint devices and the four force measuring sensors are arranged at a heading constraint point, wherein the heading constraint point comprises two frames with stronger bearing capacity in the front fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the front fuselage and the stringers, and two frames with stronger bearing capacity in the rear fuselage, which are symmetrical left and right along the fuselage axis, at the intersection point of the frames with stronger bearing capacity in the rear fuselage and the stringers;

the oil pipe is connected with the front cavity of the uniform-load restraining device on the left side and the right side of the front machine body and the front cavity of the uniform-load restraining device on the left side and the right side of the rear machine body, is connected with the pressure pump and is used for providing pressure.

6. The parallel fuselage heading unidirectional restriction system of claim 5, wherein the medium used in the uniform load restriction device is uncompressed oil.

7. A parallel fuselage heading unidirectional restraint system according to claim 5 or 6, wherein the load sharing restraint device is a hydraulic ram.

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