M icro A ir V ehicle Wing Deployment System April 7, 2005 MAV erick S olutions Todd Adkins Leroy Cohen Jr. Adam Hollrith Brian Moore Sponsored by: Eglin AFB
Objectives Design and fabricate component technology that will provide a MAV the capability to collapse/fold all wing surfaces along the body of the fuselage Assess current materials and technologies that will maximize subsystem performance and minimize size and weight (i.e. composites, plastic actuators) Furnish final report documenting project objective, approach, results, budget analysis for hardware used, and conclusions
Specifications
Design Approach ¶Develop Wing Folding Configurations – Various paths of motion – Type of wing Single Bi-Wing ·Develop Actuation Mechanism – Move Wings from Stowed to Deployed position – Minimal interference ¸Modular System – Contain all Mechanical and Structural components – Easily implemented into existing MAV Fuselage
Wing Concepts Concept #1 Involves a pair of wings that fold along the sides of the fuselage Pros - Compact design Cons - Complicated deployment path - Multiple driving mechanisms - Two separately moving wings
Wing Concepts Concept #2 Involves a one-piece, rotating wing Pros - Simple deployment - Compact design - One rotating mechanism - One-piece wing design Cons - Concentrated stress on single support - Possible interference with tail of MAV
Wing Concepts Concept #3 Involves a bi-wing design that will allow for greater lift capabilities and improved glide slope Pros - Greater lift capabilities than concept 2 - One-piece wing design - Central rotating mechanism Cons - Possible wing interference - Greater weight
Concept #4 Comprised of a two-wing system that simply rotates into deployment The wings overlap on the top of the vehicle fuselage while stowed Pros - Simple and quick deployment - Compact design Cons -Interference caused by overlapping wings - Two wing attachment points Wing Concepts
Concept #5 Comprised of one central connection between the wings and the fuselage Both wings will rotate from the same point Pros -Central rotation point -Compact design -Simple and quick deployment Cons -Offset wings -Relatively more complex concentric shafts
Concept Matrix Scale Factor (1-10) 10 - optimal Concept 4
Deployment Mechanism Concepts Linkage System Actuator Servo Driven Gear Servo Driven
Actuator Deployment
Linkage Deployment
Gear Set Deployment
Design Analysis - Lift & Drag Lift Force (N) Vs. Velocity of MAV (mph) Weight of MAV = N To maintain flight, Lift Force must equal N
Design Analysis - Lift & Drag Maximum Torque on Wings at Maximum Velocity (25 mph) T wings = 1.90 N*cm Torque Provided by Servo T servo = 2.94 N*cm Final Comparison T shafts > T wings Torque on wings (N*cm) vs. MAV Velocity (mph)
Design Analysis – Linkages
Gear Analysis Number of Teeth Gear Ratio Diameter Torque Stresses – Bending Safety Factors
Module Design
Design Selection Gear System Efficient Relatively Simple Compact Reliable
Specification Changes Modify overall dimensions of Module
Fabrication Process Module Components Stock Modified Machined
Fabrication Process
Testing Results Torque Test Tested at max. torque requirement Gears did not bind and shafts rotated smoothly Rotational Timing Servo moved to correct position in less than 1 second
Testing Results Stowing Test Wing attachment arms and shafts bent severely when packaged in tube Gears would bind and wings could not deploy properly
Design Modifications Create new method for attaching wings to rotating shafts Implement support bracket hinge system Previous DesignModified Design
Final Modified Assembly
Final Cost Analysis
Final Product Successfully stowed in 3” tube Deployed in less than 1 second Final module weight of 28 g
Final Product
References bin/products.cgi?CAT=23 html
Special Thanks Eglin Air Force Base Edwardo Freeman FAMU/FSU College of Engineering Dr. Cesar Luongo Dr. Patrick Hollis Dan Braley Keith Larson