Design of a Compliant Variable Camber Mechanism for Airfoils using Pseudo-Rigid Body Analysis

Abstract

Slat and flap mechanisms on modern aircraft are used to control the camber of an airfoil to improve flight efficiency in various flight conditions. Implementation of these systems is often hindered by their size, complexity, and cost. In this report the design of a compliant mechanism to enable a variable camber of an airfoil is discussed as an alternative solution. The design is carried out by creating a four-bar linkage for both the leading and trailing edges of an airfoil with the movement desired for morphing. The pseudo-rigid body model is then used to create a set of compliant flexures with the same behavior as this linkage. The method of manufacturing a prototype of the design was chosen to be additive manufacturing with an elastically deformable thermoplastic, polypropylene, for the morphing mechanism and Polyethylene terephthalate glycol (PETG) for the rigid region. Such a design can decrease the complexity of subsystems involved for morphing behavior. This can open paths of integration into aircraft that are not currently capable of housing such a system.