CN110375050A - A kind of new spatial Intelligent telescopic transport structure based on multistable curved beam - Google Patents

Abstract

A kind of new spatial Intelligent telescopic transport structure based on multistable curved beam, is related to a kind of Intelligent telescopic transport structure.Compound negative stiffness unit cell includes Curved Beam Structure and three support constructions, Curved Beam Structure two sides are arranged symmetrically, and there are two Stiff Blocks to change cross sectional dimensions, every four compound negative stiffness unit cell combinations are fixed into compound negative stiffness honeycomb, spring is fixed among the Curved Beam Structure of the compound negative stiffness unit cell of often opposite two, every eight compound negative stiffness honeycombs form support arm monomer, multiple support arm monomer compositions transport support arm, transport platform with transport support arm one end and be fixedly connected by binder, it transports platform outboard surface and is equipped with and transport part locating cover.With shape memory function, it can be realized flexible by temperature control and bent without dead angle, light weight, strong flexibility can also carry out operation in small space.

Description

A new space intelligent telescopic transport structure based on multi-stable curved beams

technical field

The invention relates to an intelligent telescopic transport structure, in particular to a novel space intelligent telescopic transport structure based on multi-stable curved beams.

Background technique

At present, the transportation structure on the market is generally a mechanical transmission structure. The parts are generally made of rigid materials, and the rigid materials have limited elastic deformation capacity, and their own quality is relatively heavy. , cannot be integrally formed, such as working in some small spaces will face difficulties.

The multi-stable structure is a new type of lightweight multi-functional structure that has attracted widespread attention at home and abroad in recent years. Due to its special properties or functions such as negative stiffness effect, multi-stable effect, and repeatable characteristics, it can absorb energy in impact. , shape-transforming metamaterials, and expandable structures have broad application prospects. A multistable structure is a mechanical superstructure with high initial stiffness and recoverability, which utilizes jumps in beam buckling modes to achieve negative stiffness effects. The multistable structure has multistable characteristics. The beam will undergo irreversible deformation during the buckling process and cannot return to the initial state after unloading. In this way, a similar self-locking phenomenon occurs, thereby storing part of the deformation energy in the structure.

Shape memory polymer is a polymer with the characteristics of actively recovering deformation and maintaining shape under certain thermal, electrical, magnetic and optical stimuli. After adding carbon fiber reinforcement phase, its strength will also increase a lot.

To sum up, the existing transportation machinery has a heavy structure, cannot expand and contract in the axial direction, needs hinge connections at corners, cannot be integrally formed, and has no shape memory function. If the transport structure can be optimized and improved by using a multi-stable structure combined with a shape memory polymer, it has practical significance for solving the disadvantages of the existing transport mechanical structure.

Contents of the invention

The object of the present invention is to provide a new space intelligent telescopic transport structure based on multi-stable curved beams to solve the above problems.

In order to achieve the above object, the present invention adopts the following technical solutions: a new type of space intelligent telescopic transport structure based on multi-stable curved beams, including a transport support arm and a transport platform, and the transport support arm includes several composite Negative stiffness unit cell, the composite negative stiffness unit cell includes a curved beam structure and three support structures, the curved beam structure is made of shape memory polymer containing reinforced fibers, the support structure is nylon, and the three support structures are respectively It is vertically fixed in the middle and both ends of the curved beam structure as a whole. The two supporting structures at both ends are located on the same side and opposite to the supporting structure in the middle. Two rigid blocks are arranged symmetrically on both sides of the curved beam structure to change the cross section. Size, every four composite negative stiffness unit cells are combined and fixed into a composite negative stiffness honeycomb structure, and the four composite negative stiffness cells of the composite negative stiffness honeycomb structure are opposed to each other in pairs and then fixed on one side to form a horizontal and vertical two-way Symmetrical Japanese-shaped structure, with springs fixed in the middle of the curved beam structures of each of the two composite negative-stiffness units facing each other, and eight composite negative-stiffness honeycomb structures ringed to one side and fixed in turn to form a regular octagon to form a support The arm is a single body, and a plurality of said support arm monomers are fixed in sequence along the axial direction to form a transport support arm. The transport support arm can be stretched in a straight line and bent without dead ends by temperature control of the curved beam structure. The platform and one end of the transport support arm are fixedly connected by an adhesive, and a transport positioning cover is installed on the outer surface of the transport platform. The outer surface of the transportation platform is formed with an internal thread storage groove, and the positioning cover of the transportation part is screwed and fixed to the internal thread storage groove of the transportation platform through the external thread joint.

Compared with the prior art, the beneficial effect of the present invention is that the composite negative stiffness unit cell of the present invention has a shape memory function, can realize multiple stable states through temperature control, and realize expansion and contraction in the axial direction and no dead angle bending , the maximum bending angle in a single direction is 180°, it has zero Poisson’s ratio effect, the cross-section size remains unchanged, and the cross-section is always the same as the initial shape during the stretching and bending process without ellipse, and the curved beam structure has many In a stable state, self-locking can be performed without changing the temperature, no auxiliary facilities are required, no hinge connection is required at the corner, it can be directional loaded and transported, it has the characteristics of large transmission and large rotation, and can be quickly stored, stretched and bent. Realize one-dimensional, two-dimensional, three-dimensional movement, light weight, strong flexibility, and work in a narrow space, which has practical significance for the research and application of transportation structures.

Description of drawings

Fig. 1 is the schematic diagram of composite negative stiffness unit cell of the present invention from expanded state to compressed state;

Fig. 2 is the schematic diagram of the composite negative stiffness honeycomb structure of the present invention in a compressed state;

Fig. 3 is the schematic diagram of the composite negative stiffness honeycomb structure of the present invention in the unfolded state;

Fig. 4 is the axonometric view of the support arm monomer of the present invention;

Fig. 5 is a schematic diagram of the transport support arm of the present invention when it is bent;

Fig. 6 is an axonometric view of the transport support arm of the present invention after being bent;

Fig. 7 is an axonometric view of the curved outer side of the transport support arm of the present invention after it is bent;

Fig. 8 is an axonometric view of the bending inner side of the transport support arm of the present invention after it is bent;

Fig. 9 is a schematic diagram of a new space intelligent telescopic transport structure based on a multi-stable curved beam of the present invention;

Fig. 10 is a schematic diagram of the disassembled structure of the transport positioning cover and the transport platform of the present invention;

Fig. 11 is a schematic diagram of two-dimensional sinusoidal movement of the transport support arm of the present invention;

Fig. 12 is a schematic diagram of the two-dimensional ladder-shaped movement of the transport support arm of the present invention;

Fig. 13 is a schematic diagram of the two-dimensional circular motion of the transport support arm of the present invention;

Fig. 14 is a schematic diagram of the three-dimensional helical movement of the transport support arm of the present invention;

Fig. 15 is a schematic diagram of a three-dimensional arbitrary direction movement of the transport support arm of the present invention;

Figure 16 is a schematic diagram of two variant structures of the curved beam structure of the present invention.

Detailed ways

The technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, not all of them. Based on the present invention All other embodiments obtained by persons of ordinary skill in the art without creative efforts, all belong to the scope of protection of the present invention.

Specific Embodiment 1: As shown in Figures 1 to 10, the present invention discloses a new space intelligent telescopic transport structure based on multi-stable curved beams, including a transport support arm 11 and a transport platform 12. The support arm 11 includes several composite negative stiffness unit cells 1, the composite negative stiffness unit cells 1 include a curved beam structure 1-1 and three support structures 1-2, and the curved beam structure 1-1 adopts a reinforced Fiber shape memory polymer, the support structure 1-2 is made of nylon, the three support structures 1-2 are vertically fixed to the middle and both ends of the curved beam structure 1-1 respectively, and the two support structures 1-2 at the two ends 2 are located on the same side and set opposite to the support structure 1-2 in the middle. Two rigid blocks 1-3 are symmetrically arranged on both sides of the curved beam structure 1-1 to change the cross-sectional size. Each of the four composite negative rigidity units The cells 1 are combined and fixed into a composite negative stiffness honeycomb structure 2, and the four composite negative stiffness unit cells 1 of the composite negative stiffness honeycomb structure 2 are opposed to each other in pairs, and then fixed on one side to form a horizontal and vertical two-way symmetrical Japanese-shaped structure, A spring 2-1 is fixed in the middle of the curved beam structures 1-1 of each of the two composite negative stiffness unit cells 1, and each of the eight composite negative stiffness honeycomb structures 2 is fixed from the beginning to the end in order to form a regular octagon. The support arm unit 3 is formed, and a plurality of the support arm units 3 are sequentially fixed along the axial direction to form the transport support arm 11. The transport support arm 11 can realize linear extension and infinite Bending at a dead angle, the transport platform 12 and one end of the transport support arm 11 are fixedly connected by an adhesive, and a transport positioning cover 13 is installed on the outer surface of the transport platform 12, and the shape of the transport positioning cover 13 is hemispherical The shell and its open end are shaped on an external thread joint 13-1, and the outer surface of the transport platform 12 is shaped on an internal thread storage groove 12-1, and the positioning cover 13 of the transport part is connected with the transport platform through the external thread joint 13-1 The internal thread storage groove 12-1 of 12 is screwed and fixed.

Specific embodiment 2: As shown in Figures 1 and 5, this embodiment is a further description of specific embodiment 1. The plurality of composite negative stiffness unit cells 1 are in the unfolded state and are higher than the curved beam structure 1 In the case of a material with a glass transition temperature of -1, it is compressed under the drive of an external load to produce bending deformation for shaping, and after the shape is shaped, it is naturally cooled and fixed to form the transport support arm 11. When the transport support arm 11 All the curved beam structures 1-1 are heated to the same temperature at the same time, and all the curved beam structures 1-1 return to the unfolded state to release the prestress to make the transport support arm 11 stretch in a straight line. When the transport support arm 11 is bent outside the curved beam structure 1-1 The heating time is longer than that of the curved beam structure 1-1 on the inside of the bend, and the curved beam structure 1-1 on the outside of the bend is expanded longer than the curved beam structure 1-1 on the inside of the bend, so that the transport support arm 11 bends to the inside of the bend .

Embodiment 3: As shown in Figure 1, this embodiment is a further description of Embodiment 2. The two sides of the curved beam structure 1-1 use polyimide adhesive to paste the electric heating sheet on the The inner surface of the shape memory polymer containing reinforcing fibers in the initial unfolded state is controlled by a temperature controller to control the temperature of the electric heating plate, thereby controlling the temperature of the curved beam structure 1-1.

Embodiment 4: As shown in FIG. 4, this embodiment is a further description of Embodiment 1. The composite negative stiffness honeycomb structures 2 are seamlessly connected by high temperature curing. In order to perform seamless connection, The composite negative stiffness honeycomb structure 2 interface is set as a slope.

Embodiment 5: As shown in Figure 5, this embodiment is a further description of Embodiment 1. The transport support arm 11 is a structure with a thick root and a thin head, which saves materials without affecting the strength. .

Embodiment 6: As shown in Figures 1 and 16, this embodiment is a further description of Embodiment 1. The curved beam structure 1-1 can be replaced by two variant structures, including curved beam variant structure 1 -11 and curved beam variant structure two 1-12, the cross-sectional dimension of said curved beam variant structure one 1-11 is a form narrow in the middle and wide at both ends, and the cross-sectional dimension of said curved beam variant structure two 1-12 is A form that is wide in the middle and narrow at both ends.

Embodiment 7: As shown in FIG. 10 , this embodiment is a further description of Embodiment 1. A plurality of radial springs 14 are evenly fixed on the inner wall of the positioning cover 13 of the transporting member, and each radial spring 14 The free end of the spring 14 is fixed with a supporting block 14-1.

Referring to Fig. 1, add rigid blocks 1-3 on the curved beam structure 1-1 to increase the cross-sectional size of the curved beam structure 1-1, if more rigid blocks 1-3 are added at different positions, Or change the cross-sectional area of the curved beam structure 1-1 at different positions. With reference to the shown in Figure 16, the curved beam structure 1-1 is modified, such as the curved beam variant structure 1-11 with a narrow middle and two wide ends and a wide middle two. The narrow-end curved beam variant structure 2 1-12 is prone to buckling at the position with a relatively small cross-sectional size, which can realize the multi-stable function and is conducive to the stability of the structure during bending. Refer to Figures 2-3 As shown, the composite negative stiffness honeycomb structure 2 adds spring 2-1 so that when it is compressed and expanded, there is prestress stored inside the spring 2-1, which makes it easier to compress and expand the composite negative stiffness honeycomb structure 2.

Referring to Figures 1 to 5, a support structure 1-2 made of nylon and a curved beam structure 1-1 made of a shape memory polymer containing reinforced fibers are fixedly combined into a transport support arm 11, wherein the curved beam Structure 1-1 can be reinforced by using epoxy resin shape memory polymer and setting fibers on the surface, put it in the temperature box under the condition of 90°C for 2 hours in the initial unfolded state, and then carry out high temperature under the condition of 120°C Curing for 1 hour, then, take out the transport support arm 11 and paste the electric heating sheet on the curved beam structure 1-1, put the transport support arm 11 with the electric heating film into the temperature box at 100-120°C, the specific temperature depends on the curved beam structure 1-1. Beam structure 1-1 is determined by the glass transition temperature Tg of the material, which is generally 0-20°C higher than Tg. Place it in the temperature box for 10 minutes. After the material reaches Tg and softens, take it out of the temperature box. The transport support arm 11 is compressed, and the material returns to normal temperature and keeps its shape. Referring to FIGS. The screw connection of the transport platform 12 is convenient for installation and disassembly, and the inner wall of the transport part positioning cover 13 is evenly fixed with multiple radial springs 14, and the free end of the radial spring 14 is fixed with a support block 14-1, which can compress and position the transport parts , the electric heaters are electrically connected to the temperature controller through electric wires, and the electric wires are arranged inside the transport support arm 11. After power-on, the temperature control of the electric heaters is carried out through the temperature controller. Heating, the curved beam structure 1-1 will gradually return to the unfolded state. If you want to stop it in a certain state, you can stop heating up and keep the temperature when it reaches this state. If you only need to transport the support arm 11 for one-dimensional For linear extension of motion, it is only necessary to control the heating time and temperature of the electric heating plates at the same circumferential position to be the same, so that the curved beam structure 1-1 at the same circumferential position is in the same stable state, as shown in Figures 5-7, If it is necessary to transport the support arm 11 for bending, it is only necessary to control the electric heating sheet at the same circumferential position to increase the temperature on the outside of the bend when heating, so that the curved beam structure 1-1 unfolds smaller as it moves toward the inside of the bend, and the more it is in In the compressed state, the compression on the inside of the bend is relatively large, and the compression on the outside of the bend is relatively small, and the middle part is in the intermediate stable state of the two for transition. The transport support arm 11 can realize the two-dimensional bending shown in Fig. 11 through the temperature regulation of different bending parts. One-dimensional sinusoidal motion, two-dimensional stepped motion shown in Figure 12, two-dimensional circular motion shown in Figure 13, three-dimensional spiral motion shown in Figure 14, and three-dimensional arbitrary direction shown in Figure 15 Movement to meet the needs of support and transportation.

It will be obvious to a person skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, but that it can be implemented in other configurations without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents are included in the invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (7)

1. A novel space intelligent telescopic transport structure based on multi-stable curved beams, characterized in that: it comprises a transport support arm (11) and a transport platform (12), and the transport support arm (11) includes several A composite negative stiffness unit cell (1), the composite negative stiffness unit cell (1) includes a curved beam structure (1-1) and three support structures (1-2), the curved beam structure (1-1 ) adopts a shape memory polymer containing reinforcing fibers, the support structure (1-2) is nylon, and the three support structures (1-2) are respectively vertically fixed to the middle and both ends of the curved beam structure (1-1) as a whole , the two support structures (1-2) at both ends are located on the same side and opposite to the support structure (1-2) in the middle, and the curved beam structure (1-1) is symmetrically arranged with two rigid blocks ( 1-3) To change the cross-sectional size, every four composite negative stiffness unit cells (1) are combined and fixed into a composite negative stiffness honeycomb structure (2), and the four composite negative stiffness honeycomb structures (2) After two pairs of negative stiffness unit cells (1) face each other, one side is attached and fixed to form a horizontal and vertical two-way symmetrical Japanese-shaped structure, and the curved beam structure (1-1) of each opposite composite negative stiffness unit cell (1) is in the middle A spring (2-1) is fixed, and every eight composite negative-stiffness honeycomb structures (2) are fixed in sequence from the head to the tail on one side of the ring to form a regular octagon to form a single support arm (3), and multiple support arms are single The body (3) is sequentially fixed along the axial direction to form a transport support arm (11), and the transport support arm (11) can be stretched in a straight line and bent without dead ends by controlling the temperature of the curved beam structure (1-1). The transportation platform (12) is fixedly connected to one end of the transportation support arm (11) by an adhesive, and the transportation platform (12) is equipped with a transportation part positioning cover (13) on the outer surface, and the transportation part positioning cover (13) The shape is a hemispherical shell and its open end is formed with an external thread joint (13-1), the outer surface of the transport platform (12) is formed with an internal thread storage groove (12-1), and the transport part positioning cover (13) passes through The externally threaded joint (13-1) is screwed and fixed to the internally threaded storage slot (12-1) of the transport platform (12). 2. A novel space intelligent telescopic transport structure based on multi-stable curved beams according to claim 1, characterized in that: the plurality of composite negative stiffness unit cells (1) are in the unfolded state and are higher than the In the case of the glass transition temperature of the material of the curved beam structure (1-1), it is compressed under the drive of an external load to generate bending deformation for molding, and after the shape is shaped, it is naturally cooled and fixed to form the transport support arm (11 ), when all the curved beam structures (1-1) of the transport support arm (11) are heated to the same temperature at the same time, all the curved beam structures (1-1) return to the unfolded state to release the prestress so that the transport support arm (11 ) stretches in a straight line, when the curved beam structure (1-1) on the outside of the transport support arm (11) is heated up, it is longer than the curved beam structure (1-1) on the inside of the bend, and the curved beam structure (1-1) on the outside is bent 1) Expanding the curved beam structure (1-1) larger than the inside of the bend causes the transport support arm (11) to bend toward the inside of the bend. 3. A novel space intelligent telescopic transport structure based on multi-stable curved beams according to claim 2, characterized in that: both sides of the curved beam structure (1-1) are bonded with polyimide Paste the electric heating sheet on the inner surface of the shape memory polymer containing reinforcing fibers in the initial unfolded state, and regulate the temperature of the electric heating sheet through a temperature controller, thereby regulating the temperature of the curved beam structure (1-1) . 4. A new space intelligent telescopic transport structure based on multi-stable curved beams according to claim 1, characterized in that: the composite negative stiffness honeycomb structures (2) are seamlessly connected by high temperature curing , for seamless connection, the interface of composite negative stiffness honeycomb structure (2) is set as a slope. 5. A new type of space intelligent telescopic transport structure based on multi-stable curved beams according to claim 1, characterized in that: the transport support arm (11) is a structure with a thick root and a thin head. Save material at the expense of strength. 6. A new type of space intelligent telescopic transport structure based on multi-stable curved beams according to claim 1, characterized in that: the curved beam structure (1-1) can be replaced by two variant structures, including curved Beam variant structure one (1-11) and curved beam variant structure two (1-12), the cross-sectional dimension of the curved beam variant structure one (1-11) is in the form of a narrow middle and wide ends, and the curved beam The cross-sectional size of variant structure 2 (1-12) is a form with a wide middle and narrow ends. 7. A novel space intelligent telescopic transportation structure based on multi-stable curved beams according to claim 1, characterized in that: the inner wall of the positioning cover (13) of the transportation part is evenly fixed with multiple radial springs ( 14), each free end of the radial spring (14) is fixed with a support block (14-1).