Design, Manufacture and Wind Tunnel Test of a Modular FishBAC Wing with Novel 3D Printed Skins

Andrés E Rivero,Stephane Fournier,Benjamin K S Woods,Rafael M Heeb

doi:10.3390/app12020652

Abstract

This paper introduces a new modular Fish Bone Active Camber morphing wing with novel 3D printed skin panels. These skin panels are printed using two different Thermoplastic Polyurethane (TPU) formulations: a soft, high strain formulation for the deformable membrane of the skin, reinforced with a stiffer formulation for the stringers and mounting tabs. Additionally, this is the first FishBAC device designed to be modular in its installation and actuation. Therefore, all components can be removed and replaced for maintenance purposes without having to remove or disassemble other parts. A 1 m span, 0.27 m chord morphing wing with a 25% chord FishBAC was built and tested mechanically and in a low-speed wind tunnel. Results show that the new design is capable of achieving the same large changes in airfoil lift coefficient (approximate ΔCL≈0.55) with a low drag penalty seen in previous FishBAC work, but with a much simpler, practical and modular design. Additionally, the device shows a change in the pitching moment coefficient of ΔCM≈0.1, which shows the potential that the FishBAC has as a control surface.

Highlights

Compliance-based camber morphing wings have the potential to improve aerodynamic performance in both fixed and rotary wings
The main objective of this wind tunnel test campaign was first, to ensure that the novel design and manufacturing techniques introduced in this latest generations of Fish Bone Active Camber (FishBAC) wings lead to structurally sound FishBAC devices that can resist the different aerodynamic load cases, and second, to evaluate its aerodynamic performance and its ability to generate changes in lift coefficient with varying camber distribution (i.e., ∆CL)
This paper presents the design, manufacture and testing of a novel composite Fish Bone Active Camber (FishBAC)=morphing device with 3Dprinted skins

Summary

Introduction

Compliance-based camber morphing wings have the potential to improve aerodynamic performance in both fixed and rotary wings. This aerodynamic improvement is due to their ability to actively vary airfoil camber in a smooth and continuous way so that the airfoil geometry can adapt to the continuous changes in operating conditions (e.g., changes in altitude, speed, weight, weather conditions). Advancements in smart materials and lightweight structures, which have led to lighter and less complex morphing mechanisms. Developments in piezoelectric materials [5,6] and Shape-Memory Alloys (SMA) [7,8] have focused on exploring alternative actuation mechanisms, whereas the further understanding of composite laminates has led to exploiting structural instabilities for shape changing [9,10,11]. Some concepts achieved variable camber by embedding actuators within the wing skin [5,12], whereas others focused on active actuation of the internal load-bearing structural members [8,13,14,15]

Objectives

Methods

Results

Conclusion