1 Inflatable structures Ir. J. Breukels Room
2 Inflatable structures Definition: An inflatable structure is a membrane structure which requires a tensile pre-stress, created by a pressure difference, to bear externally applied loads.
3 Applications - Civil engineering - Aeronautics - Space
4 Applications Civil engineering Property of Prospective Concepts, Switserland.
5 Applications Civil engineering Property of Prospective Concepts, Switserland.
6 Applications Civil engineering
7 Applications Aeronautics Goodyear Inflatoplane
8 Applications Aeronautics Prospective Concepts Stingray
9 Applications Aeronautics GLOV (Gun Launched Observation Vehicle)
10 Applications Aeronautics Inflatable kites
11 Applications Space Inflatable re-entry vehicle
12 Applications Space Inflatable solar concentrators
13 Regular beams vs Inflatable beams Regular beam mechanics
14 Regular beams vs Inflatable beams Inflatable beam mechanics
15 The principle of wrinkling
16 Wrinkling criteria Wrinkling criteria based on stress When σ = σ Wrinkling occurs bendingPressure
17 Wrinkling criteria Wrinkling criteria based on strain
18 Wrinkling propagation Wrinkling criteria based on strain
19 Three states of an inflatable beam -Unwrinkled -Wrinkled -Collapsed
20 Moment – Deflection curve
21 Moment – Deflection curve
22 Moment – Deflection curve
23 Tapered beams
24 Tensairity ® Synergetic combination of an airbeam with conventional cables and struts. Compression (strut) Tension (cable) Stabilization (air) Tensairity ® = Tension + Air + Integrity
25 Tensairity ® Property of Prospective Concepts, Switserland.
26 Tensairity ® Property of Prospective Concepts, Switserland. Tensairity ® demonstration bridge, 8m span, 3.5 t max. load
27 Building wings with inflatables -Constructing airfoils with tubes -Sailwings
28 Building wings with inflatables Constructing airfoils with tubes Pro:- Good airfoil shape Con:- Complex - Heavy
29 Building wings with inflatables Constructing airfoils with tubes
30 Building wings with inflatables Sailwings Pro:- Simple - light Con:- airfoil arbitrarily defined - only one tube to carry loads
31 Building wings with inflatables Sailwings Straight tapered wing
32 Building wings with inflatables Sailwings Elliptical wing
33 Building wings with inflatables Sailwings Arcs (surfkites)
34 Inflatable wings and control -Conventional control surfaces - Wing morphing
35 Inflatable wings and control Nature’s solution to flight control
36 Inflatable wings and control The early days
37 How to morph an inflatable wing -Pressure variation -Nastic structures -Bump flattening -Trailing edge deflection
38 How to morph an inflatable wing Pressure variation
39 How to morph an inflatable wing Nastic structures
40 How to morph an inflatable wing Nastic structures
41 How to morph an inflatable wing Nastic structures
42 How to morph an inflatable wing Bump flattening PZT -> Lead Zirconium Titrate
43 How to morph an inflatable wing Bump flattening
44 How to morph an inflatable wing Trailing edge deflection
45 How to morph an inflatable wing Trailing edge deflection
46 Questions?