阅读说明：本技术 一种基于形状记忆合金驱动的可变弯度机翼结构 (Variable camber wing structure based on shape memory alloy drive ) 是由 邓进军 张旭博 杨杰 李诗伟 罗剑 马炳和 于 2020-12-09 设计创作，主要内容包括：本发明公开了一种基于形状记忆合金驱动的可变弯度机翼结构,属于航空装备技术领域。机翼结构主要包括被柔性蒙皮包敷的柔性后缘结构1和前缘刚性段2；所述柔性后缘结构1为多个刚性段4依次铰接的方式构成,其与前缘刚性段2整体形成近似仿恐龙尾骨结构；柔性后缘结构的上下翼面在沿翼型弦向方向上均有合金丝。当柔性后缘结构1上翼面的形状记忆合金丝组被加热时,其长度变短,整个柔性后缘结构1产生向上变形；反之产生向下变形。本设计机翼结构简单,具有功重比较大的特点,可以主动地进行翼型变化,获得最佳气动特性；机翼能够获得不同的气动特性；采用模块化组装设计,大大节省机翼内部空间。(The invention discloses a variable camber wing structure based on shape memory alloy driving, and belongs to the technical field of aviation equipment. The wing structure mainly comprises a flexible trailing edge structure 1 coated by a flexible skin and a leading edge rigid section 2; the flexible rear edge structure 1 is formed by sequentially hinging a plurality of rigid sections 4, and the flexible rear edge structure and the front edge rigid section 2 form an approximate dinosaur tailbone structure integrally; the upper and lower wing surfaces of the flexible trailing edge structure are provided with alloy wires along the chord direction of the wing profile. When the shape memory alloy wire group of the upper airfoil surface of the flexible trailing edge structure 1 is heated, the length of the shape memory alloy wire group is shortened, and the whole flexible trailing edge structure 1 deforms upwards; whereas a downward deformation occurs. The wing has the characteristics of simple structure and large power weight, and can actively change the wing profile to obtain the optimal aerodynamic characteristics; the wings can obtain different aerodynamic characteristics; and the modularized assembly design is adopted, so that the internal space of the wing is greatly saved.)

1. The double-pass shape memory alloy driven morphing wing structure mainly comprises a flexible trailing edge structure 1 and a leading edge rigid section 2, wherein the flexible trailing edge structure 1 is coated by a flexible skin; the method is characterized in that:

the flexible rear edge structure 1 is formed by sequentially hinging a plurality of rigid sections 4, and the flexible rear edge structure and the front edge rigid section 2 form an approximate dinosaur tailbone structure integrally; from the rigid section 2 of the front edge to each rigid section 4 of the flexible trailing edge structure 1, the size is reduced in sequence, so that the whole wing forms a smooth wing surface;

each rigid segment 4 of the flexible trailing edge structure 1 is structurally characterized by: the main body of the device is a rectangular shell, a front-end bump 10 protrudes outwards from the surface of each rigid section adjacent to the previous adjacent rigid section, and one surface of each rigid section and one surface of the next adjacent rigid section are missing, so that the front-end bump 10 of the next adjacent rigid section is just accommodated in the inner cavity of the rectangular shell of the rigid section; each rigid section is connected with the front end bump 10 of the next adjacent rigid section through a through cylindrical pin 12 to form a mode that a plurality of rigid sections are sequentially hinged; a plurality of parallel thin grooves 9 along the wingspan direction are formed in the upper inner wall surface and the lower inner wall surface of the rigid section shell, the size and the position of each thin groove 9 of each rigid section 4 are corresponding, after all the rigid sections 4 are sequentially hinged, the thin grooves 9 are sequentially communicated with a plurality of through grooves penetrating through the whole flexible trailing edge structure, a plurality of shape memory alloy wires with corresponding number are arranged in the plurality of through grooves, and the alloy wires are fixed to alloy wire fixing ends 5 of the flexible trailing edge structure along the chord direction of the wing profile.

2. A two-way shape memory alloy actuated morphing wing structure as claimed in claim 1 wherein a commutating structure is added between the flexible trailing edge structure 1 to the leading edge rigid section 2 to increase the lower or upper chord length as the wing is deformed up or down.

3. The two-way shape memory alloy driven morphing wing structure is characterized in that a plurality of groups of morphing wing structures according to claim 1 are formed by arranging modular assembling structures in the spanwise direction of an airfoil.

Field of the invention

The invention belongs to the technical field of aviation equipment, and relates to a deformable flexible wing structure driven by a two-way Shape Memory Alloy (SMA).

Prior Art

At present, the morphing wing has become an important feature and development direction of advanced aviation aircrafts in the future. Different from a fixed wing, the shape of the deformable wing can be changed according to different flight tasks and flight environment conditions, so that the optimal flight performance is obtained. The fishbone-type flexible trailing edge proposed in the prior literature is characterized in that a flexible material is adopted as the trailing edge design of a main bearing structure, the airfoil main body part has the characteristics of simple structure and easiness in processing, and the trailing edge is in transition fit with the aerodynamic appearance of the whole airfoil by the lengths of spaced supporting rib plates. However, due to the matching relationship between the trailing edge structure and the actuator, the overall supporting structure of the airfoil is often difficult to design, so that the flexible skin is difficult to integrate on the premise of keeping a certain supporting capacity, the leading edge structure cannot resist the resistance caused by the deformation of the trailing edge overall beam, the actuator on the other side and the skin, and the deflection effect is poor.

Therefore, the design aims to adopt a multi-section articulated multi-joint wing trailing edge structure to meet the requirement of always keeping good flight performance in a changed flight environment

Object of the Invention

The flight environment of the aircraft is continuously changed, the aerodynamic parameters are also continuously changed, and the traditional fixed wing aircraft can only achieve the optimal flight efficiency in a specific environment and cannot adapt to variable environmental changes.

The morphing wing aircraft can utilize intelligent materials or other drivers to correspondingly change the wing appearance according to the change of the flying environment and the flying task, improve the aerodynamic characteristics and the manipulation performance of the aircraft, increase the lift and reduce the drag, increase the time and the range of the aircraft, reduce or eliminate the influence of buffeting, flutter, vortex interference and the like, and enable the aircraft to more efficiently complete various flying tasks.

This design still can possess best aerodynamic performance in order to satisfy the aircraft under different flight environment and flight task condition, drives the wing through using novel intelligent material Shape Memory Alloy (SMA), makes the wing section gentle and agreeable, level and smooth, independently change and improve its aerodynamic characteristic, possesses good characteristics such as seamless, small, light in weight, response are fast, can adapt to different flight conditions excellently, accomplish various flight tasks more efficiently.

Disclosure of Invention

In order to solve various defects of the traditional wing type structure, the invention mainly aims to design a variable wing structure by utilizing a two-way shape memory alloy, and aims to solve the problem that an aircraft cannot keep the optimal aerodynamic performance under different flight conditions.

In order to achieve the purpose, the deformation wing structure driven by the two-way shape memory alloy mainly comprises a flexible trailing edge structure 1 and a leading edge rigid section 2, wherein the flexible trailing edge structure 1 is wrapped by a flexible skin;

the flexible rear edge structure 1 is formed by sequentially hinging a plurality of rigid sections 4, and the flexible rear edge structure and the front edge rigid section 2 form an approximate dinosaur tailbone structure integrally; from the rigid section 2 of the front edge to each rigid section 4 of the flexible trailing edge structure 1, the size is reduced in sequence, so that the whole wing forms a smooth wing surface;

each rigid segment 4 of the flexible trailing edge structure 1 is structurally characterized by: the main body of the device is a rectangular shell, a front-end bump 10 protrudes outwards from the surface of each rigid section adjacent to the previous adjacent rigid section, and one surface of each rigid section and one surface of the next adjacent rigid section are missing, so that the front-end bump 10 of the next adjacent rigid section is just accommodated in the inner cavity of the rectangular shell of the rigid section; each rigid section is connected with the front end bump 10 of the next adjacent rigid section through a through cylindrical pin 12 to form a mode that a plurality of rigid sections are sequentially hinged; a plurality of parallel thin grooves 9 along the wingspan direction are formed in the upper inner wall surface and the lower inner wall surface of the rigid section shell, the size and the position of each thin groove 9 of each rigid section 4 are corresponding, after all the rigid sections 4 are sequentially hinged, the thin grooves 9 are sequentially communicated with a plurality of through grooves penetrating through the whole flexible trailing edge structure, a plurality of shape memory alloy wires with corresponding number are arranged in the plurality of through grooves, and the alloy wires are fixed to alloy wire fixing ends 5 of the flexible trailing edge structure along the chord direction of the wing profile.

When the flexible trailing edge structure 1 works, when the shape memory alloy wire set of the upper airfoil surface of the flexible trailing edge structure 1 is heated, the length of the flexible trailing edge structure is shortened due to the temperature effect, and the whole flexible trailing edge structure 1 deforms upwards due to the existence of the shape memory alloy wire set of the lower airfoil surface; on the contrary, when the shape memory alloy wire set of the lower airfoil surface of the flexible trailing edge structure 1 is heated, the lower airfoil surface alloy wire is heated to shrink, and the whole flexible trailing edge structure 1 can deform downwards due to the existence of the shape memory alloy wire set of the lower airfoil surface.

In order to enable the morphing wing structure to be assembled in a modularization mode better, a plurality of groups of morphing wing structures can be formed by arranging modularization assembly structures in the spanwise direction of the wing profile (figure 5).

In order to make the deformed wing structure generate less resistance when deformed, a reversing structure (fig. 6) can be added between the flexible trailing edge structure 1 and the leading edge rigid section 2, so that when the wing is deformed upwards or downwards, the lower side or upper side chord length is increased.

The invention has the advantages that:

1. compared with the traditional wing, the wing with the variable camber has a simple structure, and meanwhile, the shape memory alloy is used as a driver, so that the wing has the characteristic of large power factor, and can actively change the wing profile to obtain the optimal aerodynamic characteristic.

2. The variable camber wing driven by the alloy wire realizes the quantitative change of the wing shape through a feedback control system of the shape memory alloy wire, so that the wing can obtain different aerodynamic characteristics.

3. And the modularized assembly design is adopted, so that the internal space of the wing is greatly saved.

ADVANTAGEOUS EFFECTS OF INVENTION

The designed wing profile can realize the target of deflection of more than 15 degrees by referring to the center line of the wing tip under the condition of no wind load, and the deflection limit angle is about 10 degrees by taking the first pitch axis fixed point as the deflection reference point. The limit deflection time is about 4 seconds and the recovery time is about 7 seconds.

Drawings

FIG. 1 is a schematic structural diagram of an active section of a variable camber airfoil structure according to an embodiment;

FIG. 2 is a schematic view of an embodiment of a flexible trailing edge configuration;

FIG. 3 is a schematic view of a single joint structure of the trailing edge in the embodiment;

FIG. 4 is a schematic view of a flexible skin according to an embodiment;

FIG. 5 is a schematic view of an exemplary spanwise primary-secondary-primary structure of a wing structure;

FIG. 6 is a schematic structural view of a reversing mechanism for a bi-directionally variable trailing edge wing provided in an embodiment.

In the figure, 1 is a flexible trailing edge structure, 2 is a leading edge rigid section, and 11 is a flexible skin.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The invention is further described with reference to the accompanying drawings and specific embodiments.

The two-way shape memory alloy driven morphing wing structure in the embodiment mainly comprises a flexible trailing edge structure 1 coated by a flexible skin and a leading edge rigid section 2;

the flexible rear edge structure 1 comprises 8 rigid sections 4 which are sequentially hinged, and the front edge rigid section 2 and the flexible rear edge structure form an approximate dinosaur tailbone structure integrally; from the rigid section 2 of the front edge to each rigid section of the flexible trailing edge structure 1, the size is reduced in sequence, so that the whole wing forms a smooth wing surface;

each rigid segment 4 of the flexible trailing edge structure 1 is structurally characterized by: the main body of the device is a rectangular shell, a front-end bump 10 protrudes outwards from the surface of each rigid section adjacent to the previous adjacent rigid section, and one surface of each rigid section and one surface of the next adjacent rigid section are missing, so that the front-end bump 10 of the next adjacent rigid section is just accommodated in the inner cavity of the rectangular shell of the rigid section; each rigid section is connected with the front end bump 10 of the next adjacent rigid section through a through cylindrical pin 12 to form a mode that a plurality of rigid sections are sequentially hinged; the upper inner wall surface and the lower inner wall surface of the rigid section shell are provided with 10 parallel thin grooves 9 along the wingspan direction, the size and the position of each thin groove of each rigid section are corresponding, after all the rigid sections are sequentially hinged, the thin grooves 9 are sequentially communicated into 10 through grooves penetrating through the whole flexible trailing edge structure, 10 strip-shaped memory alloy wires are arranged in the 10 through grooves, and two ends of the memory alloy wires are respectively fixed on the alloy wire fixing grooves 5 of the flexible trailing edge structure 1 along the chord direction of the wing profile. The shape memory alloy wire used in this example was 0.15mm in diameter and the tensile force provided by a single wire was about 2N according to the test.

In order to make the morphing wing structure be assembled in a better modularization mode, in the embodiment, more than 3 groups of morphing wing structures are provided with the mutually matched convex blocks 8 and the grooves in the wingspan direction to form the modularization assembly. In practical use, the middle group of the morphing wing structures does not use shape memory alloy wires and only use hinged rigid section structures, and the two groups of the morphing wing structures on the two sides provide hinged rigid section structures driven by the shape memory alloy wires, so that the wings form a modular continuous assembly mode of an active 14, a passive 13 and an active 14.

To create less drag on the morphing wing structure when morphing, this embodiment adds a reversing structure (fig. 6) from the rigid section of the leading edge to the flexible trailing edge structure, such that the lower or upper chord length is increased when the wing is morphing up or down. The reversing mechanism mainly comprises an upper slide sheet 15, a lower slide sheet 16, an electromagnet mounting block 17, a spring pre-tightening transition block 18, a spring group and a limiting block 19; the upper sliding piece 15 and the lower sliding piece 16 are correspondingly installed in parallel, and an upper clamping groove 20 and a lower clamping groove 21 are respectively arranged on the upper sliding piece 15 and the lower sliding piece 16; a miniature self-holding type push-pull electromagnet is arranged in the electromagnet mounting block 17, the whole electromagnet mounting block is arranged between the upper slide piece 15 and the lower slide piece 16, and the miniature self-holding type push-pull electromagnet controls an iron core bayonet lock to be switched in the upper bayonet slot 20 or the lower bayonet slot 21;

an upper groove and a lower groove are respectively formed on the side wall of the joint of the spring pre-tightening transition block and the deformation section which are connected with the wing, and when the two grooves are in butt joint, the two grooves are in butt joint respectively to form an upper through groove 22 and a lower through groove 22;

after the reversing mechanism is installed, the reversing mechanism is fixed in the shell at the joint of the wing fixed section and the wing deformation section, and an upper slider 15 and a lower slider 16 of the reversing mechanism can freely slide in an upper through groove 22 and a lower through groove 22 formed by the wing fixed section and the wing deformation section respectively; the reversing mechanism spring group comprises 5 springs which are symmetrically distributed in parallel, one ends of the springs are fixed on the end surface of the upper sliding sheet 15 or the lower sliding sheet 16, the other ends of the springs are fixed inside the wing fixing section through the spring pre-tightening transition block 18 and used for providing a certain pre-tightening force to counteract the lateral acting force transmitted to the electromagnet locking pin by the sliding sheet in the deformation section, and therefore the stability of the reversing mechanism is improved; the reversing mechanism limiting block 19 is arranged at the front end of the wing deformation section and ensures the sliding limiting of the upper sliding sheet 15 and the lower sliding sheet 16 in the wingspan direction.

If the wing trailing edge needs to deflect upwards, firstly, an electromagnet for controlling the lower sliding piece is electrified to release an electromagnet iron core bayonet lock, so that the lower sliding piece is in a free sliding state, then the shape memory alloy wires distributed on the upper side are heated, the alloy wires can deform at the moment, a certain driving force is provided to drive the wing trailing edge to deflect upwards, and the lower side unlocked sliding piece can be driven to slide due to the fact that the wing chord length of the lower side is relatively increased, so that the action of the wing trailing edge to deflect upwards is completed; when deflecting downwards, at first through for the electro-magnet circular telegram release electro-magnet iron core bayonet lock of control upside gleitbretter, make the upside gleitbretter be in can the free sliding state, give the electro-magnet reverse circular telegram of control downside gleitbretter and pop out the dead downside gleitbretter of iron core bayonet lock, then heat the shape memory alloy silk that the downside was arranged, the alloy silk can produce deformation this moment, provide certain drive power and drive the wing trailing edge and deflect downwards, because the upside wing chord length increases relatively, can drive the slide slip piece slip of upside not locking, thereby accomplish the action that the wing trailing edge deflected downwards.