Aircraft of numerical control cut is large rotate paraboloid develops structural design

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One, the need that because space navigation develops,summarizes, the rocket lades cabin and the need that emissive capacity cannot satisfy complex space mission, begin from 60 time, had machine of numerical control cut to be able to exhibit the research of dimensional structure, appeared a lot of develop a structure novelly, be like bureau of American space navigation (the Olympus Astromast of NASA) , place of Japanese space navigation (the Hingele Mast of ISAS) , the Tetrahedral Tru of Russia. Develop as the high speed of space navigation science and technology, type of large structural frame can unfold opportunity of numerical control cut the structure stands to dimensional antenna and space will have wide perspective. Accordingly, at present and the stress that bound of each country space navigation already developed it as research in the future, develop development way of the structure on behalf of prospective space. And our country just just starts in this one domain. What the article studies is a kind special can postpone a construction, this kind of structure forms to be able to exhibit truss by lever join with a hinge, node place did not twist reed; When fold condition, flexibility of the deposit that twist reed is out of shape can, be out of shape through solving a lock to release flexibility can, make the structure achieves synchronism to spread out, become develop condition finally. 2, machine of cut of numerical control of design of whole of construction of chance of numerical control cut spreads out a structure to put a rocket to lade fold condition is in when cabin, reduce greatly lade the cubage of cabin, once blast off,enter outer space, put at working place, control systematic control by the ground, make the structure spreads out adequately, achieve working status. If the graph is shown 1 times,spread out overall sketch map for the structure, bracket of source of make a present of and brim of line of aerial join Yu Tian, and the join with dimensional platform also is to be located in same margin to be in, can use whole antenna to reflex a face so, assure to reflex the oldest utilization rate of the face, improve performance of report of source of make a present of. Graph the 2 front view that develop a structure for structural frame, plane shows hexagon, reflection face rotates for cut paraboloid. Graph 2 its are main structural technology index is: Significant line of action: 5000mm slants anxious (Offset) : 2500mm focal length: Ratio of 6250mm caliber focal length: 0.

Error of 8 shape face: Rms 0.

265 ～ 0.

3 tractor dry mass: Natural frequency of 45kg structure lowest: Be more than 5Hz fold bulk: Rules form, tall 500mm 3, construction of chance of cut of numerical control of mechanism of work of construction of chance of numerical control cut is combined by main tetrahedral unit and become, line of all day long of 3 hemline compose carries worn fluctuation string staff on the back, 3 arris are inclined abdomen lever; Chord lever node is set among string staff twist reed, make a structure can synchronous spread out, if pursue,develop a process 3, the graph shows 4 times: Structural fold condition is cylinder, diameter basically by all lever decision of diametical size, active node size, careful design cooperates, can achieve a structure " complete " fold, obtain receive high rate, height is equal to celiac lever length. When structural fold, energy of active contact deposit, after solution is locked up, contact releases energy, lever of drive first quarter spreads out up, last quarter lever spreads out downward, celiac lever circles contact to turn outwards. 4, position of space of node of machine of numerical control cut is decided really 1, of position of space of machine of cut of numerical control of node of lever of first quarter of first quarter node affirmatory more complex, can have a variety of plan, all node is rotating on paraboloid, should satisfy equation: X2i+y2i=4fzi(i is node date) (1) D/f=0.

8 (2) is when affirmatory node position, must consider the following condition: (1) is as a result of all node on paraboloid, first quarter staff grows to agree impossibly entirely, because lever appearance assures as far as possible when this design,differ not quite. (2) is designed to go to the lavatory, and lever, the standardization that node makes, assure node the uniformity of each lever angle, make a structure symmetrical as far as possible when the design. The article chooses Nextpage only one of plan try to elaborate, if the graph is shown 5 times, take first quarter staff: Node of L01=L12=L23=L34=L=co T (3) 1, 2, 3, 4 what go up in Xoy is umbriferous go up in X axis, can make a structure symmetrical so at Y axis, attainable as follows nonlinear equation group: After the course simplifies, attainable 7 when contain 7 unknown number nonlinear equation group, use Newtonian iteration formula: △ X(k)=- [F ′ (X(k)) ] - 1F(x(k)) (5) can get solution, because have heavy root, because this should notice what initiative iteration is worth to take a cost, to assure the uniformity with senior staff, the string staff that takes unit of basic triangle awl is an isosceles triangle and adjacent at the equilateral triangle, by gotten two horn point, iteration gives point of the 3rd horn, can get the dimensional seat of node of full first quarter so. 2, the height when complete fold decides construction of chance of cut of numerical control of last quarter node the length at celiac lever, to make sure the structure is complete fold achieves the requirement of the design, celiac staff must agree entirely, wait entirely namely long. If the graph is shown 3 times, a, B, C is first quarter node and the position is firm already, OA, OB, OC is inclined abdomen lever, contented: Surface of LOA=LOB=LOC=L ′ =L=co T (6) looks, 3 nonlinear equation group can see 3 unknown number, seek solution with Newtonian iterative method directly, but actual iteration begs solution failure. Know by dimensional analytic geometry, 3 spherical the impact in the space has 3 kinds of possibility only possibly: Do not intersect, intersect or intersect at 2 o'clock, as a result of the uncertainty that precision reconciles, cause the failure of solution. Can use dimensional analytic geometry to seek solution, seek solution simple, precision also can assure. If graphic representation nods A, B, C,can decide a space one plane, as a result of OA=OB=OC, nod what go up in planar ABC is umbriferous the centre of gravity that is triangular ABC surely, overweight heart makes planar vertical line, the place is taken on vertical line, take LOA=L ′ , can get the dimensional seat of bit of O. Join is all last quarter node, can get last quarter lever. Use tall stretch CFRP or Teflon data (E ＞ 200GPa) , density is less than 1.

7g/cm3, lever choose Φ 10, mural ply 2mm, can achieve the structural stiffness, quality, requirement that machines workmanship basically. First quarter lever makes an appointment with 315mm, celiac lever 500mm, last quarter lever makes an appointment with 323mm, can satisfy the requirement of fold bulk and stiffness. 3, node angle every node joins 9 lever; 6 string staff, lever of 3 inclined abdomens. Want to define the mutual point of view between these lever, ability designs the detail of node to construct. Node is rotating on paraboloid, satisfy equation F(x, y, z)=0 (7) cuts planar equation when to become construction of chance of numerical control cut spreads out fold, each lever rotates to the umbriferous direction of node plane. List the linear equation of 9 lever between clean, to cut plane umbriferous, cutting the umbriferous equation on plane according to each lever, can get each point of view. 5, design of node of machine of numerical control cut is whole can exhibit a structure to have two kinds of node, namely node of midpoint of lever of spider node chord, there are 6 to twist reed in spider node, string staff has two to twist reed in midpoint node; The corner coming back of lever all is 90 ° , ensure when fold entire staff become a bunch. The size of spider node should be more than the cut area of 9 lever, collision does not happen each other in and make sure 9 lever are spreading out changing alternate course, if pursue,6 are shown. Graph 6 spiders node is active the technology of one relevant key that node is this structure design, use twist reed to serve as active node, its driving moment basically decides the stiffness flexibility coefficient at twisting reed, initiative (node fold condition) turn round angle, final (node develops condition) turn round angle. Set coefficient of the flexibility that twist reed to be K(N.

M/deg) , initiative turn round horny Φ 0, node corner is spent for Φ , criterion driving moment expresses to be: Φ of M=k(Φ 0- ) (driving moment follows 9) to node turns angle increases and be reduced, when Φ =0, twist reed to have initiative reverse part, node driving moment reachs the least value. Node is in when developing condition completely, twist reed to still must one reverses part in order to maintain the prestressing force inside the steady state of node and structure. 6, last word the article rotates to large cut the design question that throws extent content to develop a structure undertook detailed analysis, designed this kind successfully finally to develop a structure specially. CNC Milling CNC Machining