Flexible Matrix Composite Actuators Research Articles

Design and demonstration of a flexible matrix composite morphing control surface for air gap control in a Fowler flap

A full-scale commercial aircraft morphing control surface using flexible matrix composite actuators was designed and demonstrated in this research. The muscle-like flexible matrix composite actuator is ideal for morphing structures as it deforms while actuating with the structure, and the hydraulically driven actuator can operate at pressures similar to existing aircraft hydraulic systems. Through a series of parameter studies performed with finite element models, an active spoiler was designed to control the gap between a spoiler and deployed Fowler flap. A full-scale prototype was then fabricated and tested under pseudo-aerodynamic loads. The prototype demonstrated that it can achieve the necessary deflections under the given loading condition. A closed-loop control system that allows the tip deflection of the spoiler to be precisely controlled under loading was designed.

Pressurized artificial muscles

Pressurized artificial muscles are reviewed. These actuators consist of stiff reinforcing fibers surrounding an elastomeric bladder and operate using a pressurized internal fluid. The pressurized artificial muscles, known as McKibben actuators or flexible matrix composite actuators, can be applied to a wide array of applications, including prosthetics/orthotics, robots, morphing wing technologies, and variable stiffness structures. Analytical models for predicting the response behavior have used both virtual work methods and continuum mechanics. Various nonlinear control algorithms have been developed, including sliding mode control (SMC), adaptive control, neural networks, etc. In addition to traditional fluid-driving methods, innovative techniques such as chemical and electrical driving techniques are reviewed. With improved manufacturing techniques, the operational life of pressurized artificial muscles has been significantly extended, thus making them suitable for a vast range of potential applications.

Hydrodynamic analysis, performance assessment, and actuator design of a flexible tailpropulsor in an artificial alligator

The overall objective of this research is to develop analysis tools for determining actuatorrequirements and assessing viable actuator technology for design of a flexible tail propulsorin an artificial alligator. A simple hydrodynamic model that includes both reactiveand resistive forces along the tail is proposed and the calculated mean thrustagrees well with conventional estimates of drag. Using the hydrodynamic modelforces as an input, studies are performed for an alligator ranging in size from 1 cmto 2 m at swimming speeds of 0.3–1.8 body lengths per second containing fiveantagonistic pairs of actuators distributed along the length of the tail. Severalsmart materials are considered for the actuation system, and preliminary analysisresults indicate that the acrylic electroactive polymer and the flexible matrixcomposite actuators are potential artificial muscle technologies for the system.

A biologically inspired artificial fish using flexible matrix composite actuators: analysis andexperiment

A bio-inspired prototype fish using the flexible matrix composite (FMC) muscletechnology for fin and body actuation is developed. FMC actuators are pressure drivenmuscle-like actuators capable of large displacements as well as large blocking forces.An analytical model of the artificial fish using FMC actuators is developed andanalysis results are presented. An experimental prototype of the artificial fish havingFMC artificial muscles has been completed and tested. Constant mean thrustshave been achieved in the laboratory for a stationary fish for different undulationfrequencies around 1 Hz. The experimental results demonstrate that a nearly constantthrust can be achieved through tuning of excitation frequency for given bodystiffness. Free swimming results show that the prototype can swim at approximately0.3 m s − 1.