Evaluation of a Compliant Droop-Nose Morphing Wing Tip via Experimental Tests

A morphing droop-nose wing tip with span of 1.3 m and target 2 deg droop was designed, manufactured, and tested as part of the European project Novel Air Vehicle Configurations: From Fluttering Wings to Morphing Flight. The morphing droop-nose device featured a fiberglass composite skin with optimized three-dimensional thickness distribution, which was supported by topology-optimized superelastic nickel titanium and aluminum internal compliant mechanisms. The tests included ground and low-speed wind-tunnel tests (55  m/s) with the aim of assessing the structural performance and the design chain through measurements of shape, strains, surface pressures, and total forces/moments on the model. Comparisons with the experimental results were used for validation of the computational models and optimization tools. The morphing device was able to change shape while resisting the external loads, and it was identified that the distribution of strain and shape accuracy may be improved through the use of a concurrent...

[1]  Sergio Ricci,et al.  A Two-Level Approach for the Optimal Design of Morphing Wings Based On Compliant Structures , 2011 .

[2]  Ole Sigmund,et al.  Topology synthesis of large‐displacement compliant mechanisms , 2001 .

[3]  Hans Peter Monner,et al.  DESIGN OF A SMART LEADING EDGE DEVICE FOR LOW SPEED WIND TUNNEL TESTS IN THE EUROPEAN PROJECT SADE , 2011 .

[4]  Atsushi Kawamoto,et al.  Stabilization of geometrically nonlinear topology optimization by the Levenberg–Marquardt method , 2009 .

[5]  Liyong Tong,et al.  An algorithm for eradicating the effects of void elements on structural topology optimization for nonlinear compliance , 2016 .

[6]  Srinivas Vasista,et al.  Realization of Morphing Wings: A Multidisciplinary Challenge , 2012 .

[7]  Roeland De Breuker,et al.  Experimental Evaluation of the Morphing Leading Edge Concept , 2015 .

[8]  T. Gerhold,et al.  Calculation of Complex Three-Dimensional Configurations Employing the DLR-tau-Code , 1997 .

[9]  Yong Liu,et al.  Dependence of Transformation Temperatures of NiTi‐based Shape‐Memory Alloys on the Number and Concentration of Valence Electrons , 2008 .

[10]  Hans Peter Monner,et al.  A Process Chain for Structural Optimization of a Smart Droop Nose for an Active Blown High Lift System , 2014 .

[11]  Daniel J. Inman,et al.  A Review of Morphing Aircraft , 2011 .

[12]  Rolf Radespiel,et al.  Design and Analysis of a Droop Nose for Coanda Flap Applications , 2014 .

[13]  O. Sigmund,et al.  Stiffness design of geometrically nonlinear structures using topology optimization , 2000 .

[14]  M. Zhou,et al.  The COC algorithm, Part II: Topological, geometrical and generalized shape optimization , 1991 .

[15]  Sergio Ricci,et al.  Compliant structures-based wing and wingtip morphing devices , 2016 .

[16]  M. Galle,et al.  Parallel Computation of Turbulent Flows around Complex Geometries on Hybrid Grids with the DLR-Tau Code , 1999 .

[17]  Shaker A. Meguid,et al.  Shape morphing of aircraft wing: Status and challenges , 2010 .

[18]  Jeffrey C. Lagarias,et al.  Convergence Properties of the Nelder-Mead Simplex Method in Low Dimensions , 1998, SIAM J. Optim..

[19]  Johannes Riemenschneider,et al.  Design and Testing of a Compliant Mechanism-Based Demonstrator for a Droop-Nose Morphing Device , 2015 .

[20]  S. Kota,et al.  An Effective Method of Synthesizing Compliant Adaptive Structures using Load Path Representation , 2005 .

[21]  H. P. Mlejnek,et al.  Some aspects of the genesis of structures , 1992 .

[22]  Martin D. Buhmann.  Radial Basis Functions: Theory and Implementations: Introduction , 2003 .

[23]  Rafic M. Ajaj,et al.  Morphing aircraft: the need for a new design philosophy , 2016 .

[24]  Dimitris C. Lagoudas,et al.  Aerospace applications of shape memory alloys , 2007 .

[25]  Sridhar Kota,et al.  Design of Compliant Mechanisms for Morphing Structural Shapes , 2003 .

[26]  Horst Meier,et al.  On the development of high quality NiTi shape memory and pseudoelastic parts by additive manufacturing , 2014 .

[27]  Terrence A. Weisshaar,et al.  Morphing Aircraft Systems: Historical Perspectives and Future Challenges , 2013 .

[28]  M. Bendsøe.  Optimal shape design as a material distribution problem , 1989 .

[29]  Ole Sigmund,et al.  On the usefulness of non-gradient approaches in topology optimization , 2011 .

[30]  Sridhar Kota,et al.  Flight testing of the FlexFloil™ adaptive compliant trailing edge , 2016 .