CN111997198B

CN111997198B - A developable annular tensioned integral structure

Info

Publication number: CN111997198B
Application number: CN201910446064.7A
Authority: CN
Inventors: 袁行飞; 马烁; 刘宏创
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2019-05-27
Filing date: 2019-05-27
Publication date: 2021-04-27
Anticipated expiration: 2039-05-27
Also published as: CN111997198A

Abstract

The present invention provides a deployable annular tensile integral structure, comprising 2p (p>3) horizontal rods, 2p stabilizing rods, 4p oblique cables, p vertical cables, p class I nodes, and p class II nodes and 2p class III nodes; among them, class I nodes connect two adjacent horizontal bars; class II nodes connect two horizontal bars, two stabilizer bars, and four diagonal cables; class III nodes connect one stabilizer bar, two 1 diagonal cable and 1 vertical cable; the annular tensioned overall structure in the unfolded state consists of 2p equal-length horizontal rods connected end to end through type I nodes and type II nodes to form a regular p-gon of radius R as the inner ring. Each type II node of the regular polygon is connected with two stabilizer bars with a length of h and an included angle of 2α; the plane where the stabilizer bar on each type II node is located is the normal plane of the circumscribed circle of the regular polygon passing through the node. The invention makes up for the deficiencies in the form of the existing expandable annular tension integral structure, and provides an expandable annular tension integral structure system that can balance the hoop pressure and has a high storage ratio.

Description

Can open up annular stretch-draw overall structure

Technical Field

The invention relates to the technical field of tensioning integral structures and deployable structures, in particular to a deployable annular tensioning integral structure.

Background

The integral tensioning structure is a prestress self-balancing structure system consisting of a compression bar bearing axial force and a pull rope. The rigidity of the whole tensioning structure is composed of material rigidity and geometric rigidity, and the level of the geometric rigidity is influenced by the magnitude of the prestress. The integral tensioning structure has the advantages of light weight, novel shape, large span and the like, and is widely concerned by the academic and engineering fields.

The expandable structure is a structure that can be folded and expanded. When the folding type bed is in a folding state, the whole volume is small, and the transportation is convenient; under the drive of external force, the structure gradually expands to the working state and then locks to the stable state. The expandable structure has certain application in the fields of space navigation, building structures, military engineering and the like. For the deployable structure, it is always desirable to have a better structural solution in the structure of the advantages of light weight, simple structure, being beneficial to balancing the circumferential pressure, high storage ratio and the like.

Disclosure of Invention

The invention aims to provide a simple and efficient expandable annular tensioning integral structure capable of balancing annular pressure. In order to achieve the purpose, the invention is realized by the following technical scheme:

an annular tension monolithic structure comprises 2p (p)>3) The device comprises a plurality of horizontal rods, 2p stabilizing rods, 4p oblique cables, p vertical cables, p type I nodes, p type II nodes and 2p type III nodes; wherein, the I-type node is connected with 2 adjacent horizontal rods; the II-type node is connected with 2 horizontal rods, 2 stabilizing rods and 4 oblique cables; the class III node is connected with 1 stabilizing rod, 2 oblique cables and 1 vertical cable; the annular tensioning integral structure in the unfolding state is characterized in that 2p equal-length horizontal rods are connected end to end through a type I node and a type II node to form a regular p-shaped edge with the radius of R as an inner ring, and each type II node of the regular polygon is connected with 2 stabilizer bars with the length of h and the included angle of 2 alpha; the plane where the stabilizer bar on each class II node is located is a normal plane where a regular polygon circumcircles and passes through the node; the expandable annular tension integral structure is in mirror symmetry about the plane of the regular polygon, is in rotational symmetry about the normal of the regular polygon, and has a rotation angle of

(ii) a In the unfolded state, the type I and type II nodes are rigidly connected; under the contraction state, the type I and type II nodes are hinged in a single direction, and the annular tensioning integral structure enters the contraction state after 2p horizontal rods are folded along the plane of the regular polygon method.

Further, the structure has four groups of members, 2p horizontal rods are the 1 st group of members; the 2p stabilizer bars are members of the 2 nd group; 4p oblique cables are members of a group 3; p vertical cables are members of the 4 th group; the members of the same set have uniform lengths and are prestressed in the expanded state.

Furthermore, when the structure is unfolded, the class I node and the class II node are rigidly connected with the horizontal rod, and the structure has prestress to form a structure capable of bearing load; when the structure is folded, the type I node and the type II node are hinged with the horizontal rods in a one-way mode, 2p horizontal rods are folded, the prestress of the structure disappears, and the mechanism is formed; the III-class node is a hinged node, and the pressure lever unit and the inhaul cable unit can rotate at the node.

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

the invention provides a novel expandable annular tensioning integral structure system which can balance annular pressure and is simple and efficient. The invention is composed of a compression bar and a guy cable which bear axial force, and the structural rigidity has the contribution of prestress rigidity, thereby saving a large amount of materials and reducing the dead weight. Because the contraction mode of the structure is that the horizontal rods are folded, the structure is higher in storage. The invention does not need to change the number and the length of the components to convert the system into a mechanism or a structure, and the structure can be driven to open and close only by folding and unfolding the horizontal rods. The invention has application value in the aspects of deployable antennas and stadium dome structures.

Drawings

FIG. 1 is a top view of a deployable ring-shaped tensioned monolithic structure of the invention.

Figure 2 is a side view of a deployable ring-shaped tensioned monolithic structure of the invention.

Figure 3 is a perspective view of a deployable ring-shaped tensioned monolithic structure of the present invention.

FIG. 4 is a schematic view of a type I node folding state of the deployable ring-shaped tensioned monolithic structure of the present invention.

FIG. 5 is a schematic view of a deployable state of a class I node of a deployable ring tensioned monolithic structure according to the present invention.

FIG. 6 is a schematic view of a type II node of the expandable annular tensioned monolithic structure of the present invention in an expanded state.

FIG. 7 is a schematic view of a class II node folded configuration of a deployable ring tensioned monolithic structure of the present invention.

FIG. 8 is a schematic illustration of the folding process of an expandable ring tensioned monolithic structure of the present invention.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

As shown in fig. 1, 2 and 3, a deployable ring-shaped tension monolithic structure comprises 2p (p > 3) horizontal rods 1, p upper stabilizer rods 2, p lower stabilizer rods 3, 4p oblique cables 4 and p vertical cables 5, p class i nodes 6, p class ii nodes 7 and 2p class iii nodes 8; the specific composition of the whole novel annular tension integral structure is uniquely determined by the following parameters: the number p of regular polygon nodes of the inner ring, the external circle radius R of the regular polygon of the inner ring, the length h of the stabilizer bar and the included angle alpha between the stabilizer bar and the horizontal plane.

In the unfolded state, the same group of components have the same length and prestress or the same length and prestress as much as possible; the horizontal rod 1, the upper stabilizer bar 2 and the lower stabilizer bar 3 have pre-stress, the inclined cable 4 and the vertical cable 5 have pre-stress, and the overall structure has self-balance pre-stress.

The stabilizing

bars

2 and 3 are connected with the oblique cables 4 and the vertical cables 5 through II type nodes 7 and III type nodes 8, and the oblique cables 4 and the vertical cables 5 can rotate at the nodes.

As shown in fig. 4, in the folded state, the external opening of the horizontal rod 1 is connected with the internal opening of the gusset plate 9 by a pin, so as to ensure the one-way hinge joint of the horizontal rod 1 and the gusset plate 9; the horizontal bar is folded upwards to reach the folded state of the structure.

As shown in fig. 5, the gusset plate 9 of the type i gusset 6 has 4 openings, and the plate thickness is one third of the thickness of the horizontal rod 1; two ends of the horizontal rod 1 are respectively provided with two open holes and a slot with the thickness of one third of the wall thickness of the rod piece; in the unfolded state, the two holes of the horizontal rod 1 and the two holes of the gusset plate 9 are fixed through pins, the unidirectional hinge freedom degree can be locked, and at the moment, the two horizontal rods 1 are rigidly connected into a horizontal rod with the length being two times.

As shown in fig. 6, the radial gusset 10 of the class ii node 7 has two openings; two openings are respectively arranged on the two normal gusset plates 11; two holes on the radial gusset plate 10 are unidirectionally hinged with the upper stabilizer bar 2 and the lower stabilizer bar 3 through pins; in the unfolded state, the two holes of the normal gusset plate 11 and the two holes of the horizontal rod 1 are fixed through pins, the unidirectional hinge freedom degree is locked, and at the moment, the horizontal rod 1 and the class II node 7 are in rigid connection.

As shown in fig. 7, in the folded state, the inner opening of the normal gusset plate 11 is connected with the outer opening of the horizontal rod 1 by a pin, so as to ensure the one-way hinge joint of the horizontal rod and the class ii gusset 7; the horizontal rod 1, the upper stabilizer bar 2 and the lower stabilizer bar 3 are all folded upwards to reach the folded state of the structure.

As shown in fig. 8, the folding process of the novel expandable annular tension integral structure comprises the steps of removing the fixing pins of the horizontal rod 1 and the type i node 6 and the type ii node 7, and changing rigid connection into unidirectional hinge connection; the two horizontal rods 1 connected with the type I node 6 are folded upwards in a vertical plane passing through the horizontal rods, and meanwhile, the upper stabilizer bar 2 and the lower stabilizer bar 3 are folded upwards in the vertical plane; in the folding process, the inclined cables 4 and the vertical cables 5 are loosened, the structure is changed into a mechanism, and the horizontal projection area is continuously reduced.

The above node construction is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the spirit of the present invention, and these modifications and decorations should also be regarded as being within the protection scope of the present invention.

Claims

1. The utility model provides a can expand annular stretch-draw overall structure which characterized in that: the device comprises 2p horizontal rods, 2p stabilizing rods, 4p oblique cables, p vertical cables, p I type nodes, p II type nodes and 2p III type nodes, wherein p is a natural number more than 3; wherein, the I-type node is connected with 2 adjacent horizontal rods; the II-type node is connected with 2 horizontal rods, 2 stabilizing rods and 4 oblique cables; the class III node is connected with 1 stabilizing rod, 2 oblique cables and 1 vertical cable; the annular tensioning integral structure in the unfolding state is characterized in that 2p equal-length horizontal rods are connected end to end through a type I node and a type II node to form a regular p-shaped edge with the radius of R as an inner ring, and each type II node of the regular polygon is connected with 2 stabilizer bars with the length of h and the included angle of 2 alpha; the plane where the stabilizer bar on each class II node is located is a normal plane where a regular polygon circumcircles and passes through the node; the expandable annular tension integral structure is in mirror symmetry about the plane of the regular polygon, is in rotational symmetry about the normal of the regular polygon, and has a rotation angle of

2. A deployable ring-tensioned monolithic structure according to claim 1, wherein: the structure has four groups of components, and 2p horizontal compression rods are members in a group 1; the 2p stabilizer bars are members of the 2 nd group; 4p oblique cables are members of a group 3; the p vertical cables are members in the 4 th group, and the members in the same group have consistent length and prestress.

3. A deployable ring-tensioned monolithic structure according to claim 1, wherein: the horizontal rod and the stabilizer bar have pre-stress, the inclined cable and the vertical cable have pre-stress, and the overall structure has self-balance pre-stress.

4. A deployable ring-tensioned monolithic structure according to claim 1, wherein: the connection mode of the class I node and the class II node and the pressure rod is one-way hinge joint in the contraction process and the contraction state, and the rotation direction is a regular polygon normal plane where the pressure rod is located; under the unfolding state, the connection between the class I node and the class II node and the horizontal pressure rod is fixed through a locking mechanism, and the unidirectional hinge is changed into rigid connection.