Chapter 15
Applying Macro Fiber Composite Patches to Morph Complex
Aircraft Structure
B. Tran, P. G. Ifju, M. M. Mennu, A. Brenes, and S. Shbalko
Abstract An investigation to observe the morphing capabilities of actuated macro fiber composite patches on multi-curved
aircraft surfaces was conducted. Inattentive positioning of these patches can reduce desired surface deflection and mitigate
aerodynamic performance. An initial study was performed on a 2-D fiber reinforced airfoil to observe the morphology of the
cross-section when macro fiber composite patches were actuated in different chordwise positions. This was achieved through
iterative finite element analysis using a thermal expansion method analogous to piezoelectric effects. The study was adapted to
a complex 3-D wing surface where positioning and fiber orientation were considered. The kinematic performance was
evidently affected for multi-curved versus more curvy-linear structures, where reduced surface curvature was favorable for
more trailing edge deflection. In addition, effects of non-linearity of piezoceramic composites were observed in tandem on
these complex surfaces using digital image correlation. Hysteresis and creep effects by virtue displayed kinematic behavior as
a function of time and structural geometry. For a multi-curved wing, the residual strain due to hysteresis and creep were less
apparent than for a reduced multi-curved surface.
15.1 Introduction
Macro fiber composite (MFC) patches, when implemented onto a structure, act as an effective surface pressure under an
applied electric field. As a result, an induced curvature is imposed onto the structure; the magnitude of curvature is dependent
on the intensity of the electric field. This leads to intended morphology of the geometry for appropriate utility. Probst et al.
integrated MFCs onto a micro air vehicle as a substitute for motorized flight control surfaces [1]. Usher et al. implemented
MFCs onto their own wing structure and characterized resultant curvature using Classical Laminate Plate Theory [2]. LaCroix
and Ifju adapted the study of integrated MFCs onto potential substrates [3] then analyzed their effects on aerodynamic
maneuvering for a micro air vehicle [4]. The application of surface MFCs, moreover, can be used to dampen structural
oscillation. Sodano et al. manipulated the sensorial and actuation capabilities of MFCs to monitor and dampen mechanical
vibration [5]. Other studies sought to describe the behavior of integrated piezoelectric actuators. Works such as Changhai and
Lining [6], Yeh et al. [7], Park and Moon [8], etc. characterized the hysteresis and creep effect of piezoelectric actuators.
Additional literature evaluated the performance of MFCs on multi-stable structures, as outlined in the works of Portela et al.
[9], Lee et al. [10], etc.
Evidence supported by literature highlights the unique intricacies of imbedded MFCs/piezoelectrics onto host structures;
however, the relation between the structural geometry and the kinematic behavior of piezoelectric patches was emphasized to
a lesser degree. When applying MFC patches, consideration of non-linearities with placement and orientation is necessary else
adverse outcomes from the host environment can mitigate desired effects. This becomes a detriment to optimal aircraft flight
dynamics if MFC patches were used as control surfaces. This document provides theoretical and experimental data that
furthers the study of integrating MFCs onto complex fiber reinforced structures.
B. Tran (*) · P. G. Ifju · M. M. Mennu · A. Brenes · S. Shbalko
Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, USA
e-mail: tranb@ufl.edu; ifju@ufl.edu; mmennu@ufl.edu; abrenes90@ufl.edu; sshbaklo@ufl.edu
© The Society for Experimental Mechanics, Inc. 2021
R. P. Singh, V. Chalivendra (eds.), Mechanics of Composite, Hybrid and Multifunctional Materials, Volume 6,
Conference Proceedings of the Society for Experimental Mechanics Series, https://doi.org/10.1007/978-3-030-59868-6_15
99
Applying Macro Fiber Composite Patches to Morph Complex
Aircraft Structure
B. Tran, P. G. Ifju, M. M. Mennu, A. Brenes, and S. Shbalko
Abstract An investigation to observe the morphing capabilities of actuated macro fiber composite patches on multi-curved
aircraft surfaces was conducted. Inattentive positioning of these patches can reduce desired surface deflection and mitigate
aerodynamic performance. An initial study was performed on a 2-D fiber reinforced airfoil to observe the morphology of the
cross-section when macro fiber composite patches were actuated in different chordwise positions. This was achieved through
iterative finite element analysis using a thermal expansion method analogous to piezoelectric effects. The study was adapted to
a complex 3-D wing surface where positioning and fiber orientation were considered. The kinematic performance was
evidently affected for multi-curved versus more curvy-linear structures, where reduced surface curvature was favorable for
more trailing edge deflection. In addition, effects of non-linearity of piezoceramic composites were observed in tandem on
these complex surfaces using digital image correlation. Hysteresis and creep effects by virtue displayed kinematic behavior as
a function of time and structural geometry. For a multi-curved wing, the residual strain due to hysteresis and creep were less
apparent than for a reduced multi-curved surface.
15.1 Introduction
Macro fiber composite (MFC) patches, when implemented onto a structure, act as an effective surface pressure under an
applied electric field. As a result, an induced curvature is imposed onto the structure; the magnitude of curvature is dependent
on the intensity of the electric field. This leads to intended morphology of the geometry for appropriate utility. Probst et al.
integrated MFCs onto a micro air vehicle as a substitute for motorized flight control surfaces [1]. Usher et al. implemented
MFCs onto their own wing structure and characterized resultant curvature using Classical Laminate Plate Theory [2]. LaCroix
and Ifju adapted the study of integrated MFCs onto potential substrates [3] then analyzed their effects on aerodynamic
maneuvering for a micro air vehicle [4]. The application of surface MFCs, moreover, can be used to dampen structural
oscillation. Sodano et al. manipulated the sensorial and actuation capabilities of MFCs to monitor and dampen mechanical
vibration [5]. Other studies sought to describe the behavior of integrated piezoelectric actuators. Works such as Changhai and
Lining [6], Yeh et al. [7], Park and Moon [8], etc. characterized the hysteresis and creep effect of piezoelectric actuators.
Additional literature evaluated the performance of MFCs on multi-stable structures, as outlined in the works of Portela et al.
[9], Lee et al. [10], etc.
Evidence supported by literature highlights the unique intricacies of imbedded MFCs/piezoelectrics onto host structures;
however, the relation between the structural geometry and the kinematic behavior of piezoelectric patches was emphasized to
a lesser degree. When applying MFC patches, consideration of non-linearities with placement and orientation is necessary else
adverse outcomes from the host environment can mitigate desired effects. This becomes a detriment to optimal aircraft flight
dynamics if MFC patches were used as control surfaces. This document provides theoretical and experimental data that
furthers the study of integrating MFCs onto complex fiber reinforced structures.
B. Tran (*) · P. G. Ifju · M. M. Mennu · A. Brenes · S. Shbalko
Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, USA
e-mail: tranb@ufl.edu; ifju@ufl.edu; mmennu@ufl.edu; abrenes90@ufl.edu; sshbaklo@ufl.edu
© The Society for Experimental Mechanics, Inc. 2021
R. P. Singh, V. Chalivendra (eds.), Mechanics of Composite, Hybrid and Multifunctional Materials, Volume 6,
Conference Proceedings of the Society for Experimental Mechanics Series, https://doi.org/10.1007/978-3-030-59868-6_15
99