Stiffness tailoring using prestress in adaptive composite structures

Adaptive aerostructures offer the potential of increasing both aerodynamic and structural efficiency compared to conventional aerospace technologies. However, there is frequently an awkward trade-off between designing for large deformations whilst being able to withstand external loads. Multistable laminates which derive their multistability via thermal expansion mismatches are of interest for adaptive structures due to their ability to demonstrate relatively high stiffness in multiple stable states whilst being able to undergo large deformations with reduced stiffness. In addition, actuators only need to work during transition between stable shapes. However, many practical problems have arisen with the application of these laminates when designing adaptive structures. Such problems include hygrothermal variability, a limited design space with regards to achievable shape change, and insufficient stiffness for many applications. Prestressing technologies offer solutions to all of these problems. This paper summarises recent developments concerning the various means by which prestress can be used for stiffness tailoring in adaptive structures. Example prestressed structures are given including camber and twist change morphing airfoils. The use of prestress for stiffness tailoring in the design of novel passive vibration isolators and adaptive air intakes is also discussed.

[1]  Christopher R. Bowen,et al.  Bistable composite laminates: Effects of laminate composition on cured shape and response to thermal load , 2010 .

[2]  Ron Barrett,et al.  Post-Buckled Precompressed Techniques in Adaptive Aerostructures: An Overview , 2010 .

[3]  Paul M. Weaver,et al.  Bistable Prestressed Symmetric Laminates , 2010 .

[4]  Siamak Motahhari,et al.  Impact Strength of Fiber Pre-Stressed Composites , 1998 .

[5]  Paul M. Weaver,et al.  Multi-stable composite twisting structure for morphing applications , 2012, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[6]  K A Seffen,et al.  Compliant shell mechanisms , 2012, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[7]  Paul M. Weaver,et al.  Postbuckling optimisation of variable angle tow composite plates , 2013 .

[8]  P. Weaver,et al.  Optimisation of a 4-layer laminated cylindrical shell to meet given cross-sectional stiffness properties , 2006 .

[9]  Paul M. Weaver,et al.  Optimisation of blended bistable laminates for a morphing flap , 2012 .

[10]  Paul M. Weaver,et al.  ON BENEFICIAL ANISOTROPIC EFFECTS IN COMPOSITE STRUCTURES , 2002 .

[11]  J. Ashton,et al.  On the influence of pre-stress on the mechanical properties of a unidirectional GRE composite , 1997 .

[12]  Keith A. Seffen,et al.  Multistable corrugated shells , 2008, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[13]  C.M.C. Roque,et al.  Static analysis of functionally graded plates using third-order shear deformation theory and a meshless method , 2005 .

[14]  Marc R. Schultz,et al.  A Concept for Airfoil-like Active Bistable Twisting Structures , 2008 .

[16]  Ron Barrett,et al.  Solid State Adaptive Rotor Using Postbuckled Precompressed, Bending-Twist Coupled Piezoelectric Actuator Elements , 2012 .

[17]  Tarun Kant,et al.  A critical review of recent research on functionally graded plates , 2013 .

[18]  Keith A. Seffen,et al.  Multistable Textured Shell Structures , 2008 .

[19]  Asme,et al.  A collection of technical papers : 43rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference : 10th AIAA/ASME/AHS Adaptive Structures Forum : 4th AIAA Non-Deterministic Approaches Forum : 3rd AIAA Gossamer Spacecraft Forum, Denver, Colorado, 22-25 April 2002 , 2002 .

[20]  Keith A. Seffen Hierarchical multi-stable shapes in mechanical memory metal , 2007 .

[21]  Phil Mellor,et al.  Bistable Composite Flap for an Airfoil , 2010 .

[22]  Farhan Gandhi,et al.  Bistable arches for morphing applications , 2013 .

[23]  Michael W. Hyer,et al.  Some Observations on the Cured Shape of Thin Unsymmetric Laminates , 1981 .

[24]  Paul M. Weaver,et al.  Pseudo-bistable self-actuated domes for morphing applications , 2012 .

[25]  Paul M. Weaver,et al.  Environmental effects on thermally induced multistability in unsymmetric composite laminates , 2009 .

[26]  Mark E. Tuttle,et al.  Controlling Thermal Stresses in Composites by Means of Fiber Prestress , 1996 .

[27]  Paul M. Weaver,et al.  A zero torsional stiffness twist morphing blade as a wind turbine load alleviation device , 2013 .

[28]  Paul M. Weaver,et al.  Tristability of an orthotropic doubly curved shell , 2013 .

[29]  Sergio Pellegrino,et al.  Compliant multistable structural elements , 2008 .

[30]  Paul M. Weaver,et al.  Prebuckling and buckling analysis of variable angle tow plates with general boundary conditions , 2012 .

[31]  I. Zhigun Experimental evaluation of the effect of prestressing the fibers in two directions on certain elastic characteristic of woven-glass reinforced plastics , 1968 .

[32]  Sergio Pellegrino,et al.  Bistable prestressed shell structures , 2004 .

[33]  Carmel Majidi,et al.  Nonlinear geometric effects in mechanical bistable morphing structures. , 2012, Physical review letters.

[34]  Sergio Pellegrino,et al.  A NOVEL ACTUATED COMPOSITE TAPE-SPRING FOR DEPLOYABLE STRUCTURES , 2004 .

[35]  Paul M. Weaver,et al.  Design and testing of a deformable wind turbine blade control surface , 2012 .

[36]  R. Marissen,et al.  Influence of artificial pre-stressing during curing of CFRP laminates on interfibre transverse cracking , 1992 .

[37]  Paul M. Weaver,et al.  A Morphing Composite Air Inlet with Multiple Stable Shapes , 2011 .

[38]  L. F. Campanile,et al.  Initial Thoughts on Weight Penalty Effects in Shape-adaptable Systems , 2005 .

[39]  Paul M. Weaver,et al.  Analysis of unsymmetric CFRP–metal hybrid laminates for use in adaptive structures , 2010 .

[40]  Michael W. Hyer,et al.  Calculations of the Room-Temperature Shapes of Unsymmetric Laminatestwo , 1981 .

[41]  Paul M. Weaver,et al.  Bistable prestressed buckled laminates , 2008 .

[42]  S. Guest,et al.  Prestressed Morphing Bistable and Neutrally Stable Shells , 2011 .

[43]  David J. Wagg,et al.  Dynamic Analysis of High Static Low Dynamic Stiffness Vibration Isolation Mounts , 2013 .

[44]  L. Mahadevan,et al.  Multi-stability of free spontaneously curved anisotropic strips , 2011, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[45]  Paul M. Weaver,et al.  Twisting structures with tailored stability and their application to morphing wings , 2012 .

[46]  Sergio Pellegrino,et al.  A Zero-Stiffness Elastic Shell Structure , 2011 .

[47]  Sergio Pellegrino An Asymmetrically-Bistable Monolithic Energy-Storing Structure , 2004 .