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Synthesis Lectures onMechanical Engineering

Unmanned Aircraft DesignA Review of Fundamentals

Mohammad Sadraey, Southern New Hampshire University

This book provides fundamental principles, design procedures, and design tools for unmanned aerial vehicles (UAVs) with three sections focusing on vehicle design, autopilot design, and ground system design. The design of manned aircraft and the design of UAVs have some similarities and some differences. They include the design process, constraints (e.g., g-load, pressurization), and UAV main components (autopilot, ground station, communication, sensors, and payload). A UAV designer must be aware of the latest UAV developments; current technologies; know lessons learned from past failures; and they should appreciate the breadth of UAV design options. The contribution of unmanned aircraft continues to expand every day and over 20 countries are developing and employing UAVs for both military and scientific purposes. A UAV system is much more than a reusable air vehicle or vehicles. UAVs are air vehicles, they fly like airplanes and operate in an airplane environment. They are designed like air vehicles; they have to meet flight critical air vehicle requirements. A designer needs to know how to integrate complex, multi-disciplinary systems, and to understand the environment, the requirements and the design challenges and this book is an excellent overview of the fundamentals from an engineering perspective. This book is meant to meet the needs of newcomers into the world of UAVs. The materials are intended to provide enough information in each area and illustrate how they all play together to support the design of a complete UAV. Therefore, this book can be used both as a reference for engineers entering the field or as a supplementary text for a UAV design course to provide system-level context for each specialized topic.

ABOUT SYNTHESISThis volume is a printed version of a work that appears in the Synthesis Digital Library of Engineering and Computer Science. Synthesis lectures provide concise original presentations of important research and development topics, published quickly in digital and print formats. For more information, visit our website: http://store.morganclaypool.com

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Series ISSN: 2573-3168

A review of fundamentals

Mohammad Sadraey

Unmanned Aircraft DesignA Review of Fundamentals

ER/MP Gray Eagle: Enhanced MQ-1C Predator

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Synthesis Lectures on Mechanical Engineering

Synthesis Lectures on Mechanical Engineering series publishes 60–150 page publications pertain-ing to this diverse discipline of mechanical engineering. The series presents Lectures written for an audience of researchers, industry engineers, undergraduate and graduate students. Additional Synthesis series will be developed covering key areas within mechanical engineering.

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Unmanned Aircraft Design: Review of FundamentalsMohammad SadraeySeptember 2017

MEMS Barometers Towards Vertical Position Detection: Background Theory, System Prototyping, and Measurement AnalysisDimosthenis E. Bolankis2017

Vehicle Suspension System Technology and DesignAmir Khajepour and Avesta GoodarziApril 2017

Engineering Finite Element AnalysisRamana PidapartiMay 2017

Copyright © 2017 by Morgan & Claypool

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted inany form or by any means—electronic, mechanical, photocopy, recording, or any other except for brief quota-tions in printed reviews, without the prior permission of the publisher.

Unmanned Aircraft Design: A Review of Fundamentals Mohammad Sadraeywww.morganclaypool.com

ISBN: 9781681731681 printISBN: 9781681731698 ebook

DOI 10.2200/S00789ED1V01Y201707MEC004

A Publication in the Morgan & Claypool Publishers seriesSYNTHESIS LECTURES ON MECHANICAL ENGINEERING, #04

Series ISSN: 2573-3168 Print 2573-3176 Electronic

Unmanned Aircraft DesignA Review of FundamentalsMohammad H. SadraeySouthern New Hampshire University

SYNTHESIS LECTURES ON MECHANICAL ENGINEERING #04

M&C MORGAN & CLAYPOOL PUBLISHERS

vi

ABSTRACTThis book provides fundamental principles, design procedures, and design tools for unmanned aerial vehicles (UAVs) with three sections focusing on vehicle design, autopilot design, and ground system design. The design of manned aircraft and the design of UAVs have some similarities and some differences. They include the design process, constraints (e.g., g-load, pressurization), and UAV main components (autopilot, ground station, communication, sensors, and payload). A UAV designer must be aware of the latest UAV developments; current technologies; know lessons learned from past failures; and they should appreciate the breadth of UAV design options.

The contribution of unmanned aircraft continues to expand every day and over 20 countries are developing and employing UAVs for both military and scientific purposes. A UAV system is much more than a reusable air vehicle or vehicles. UAVs are air vehicles, they fly like airplanes and operate in an airplane environment. They are designed like air vehicles; they have to meet flight critical air vehicle requirements. A designer needs to know how to integrate complex, multi-disci-plinary systems, and to understand the environment, the requirements and the design challenges and this book is an excellent overview of the fundamentals from an engineering perspective.

This book is meant to meet the needs of newcomers into the world of UAVs. The materials are intended to provide enough information in each area and illustrate how they all play together to support the design of a complete UAV. Therefore, this book can be used both as a reference for engineers entering the field or as a supplementary text for a UAV design course to provide sys-tem-level context for each specialized topic.

KEYWORDSunmanned aerial vehicles, design, automatic flight control system, autopilot, drone, remotely pi-loted vehicle

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Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii

Part I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

1 Design Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 UAV Classifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.3 Design Project Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.4 Decision Making . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.5 Design Criteria, Objectives, and Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71.6 Feasibility Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.7 Design Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101.8 Design Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.9 Systems Engineering Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121.10 Conceptual Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151.11 Preliminary Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201.12 Detail Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211.13 Design Review, Evaluation, and Feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . 231.14 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2 Design Disciplines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272.2 Aerodynamic Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282.3 Structural Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302.4 Propulsion System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322.5 Landing Gear Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332.6 Mechanical/Power Transmission Systems Design . . . . . . . . . . . . . . . . . . . . . 352.7 Control Surfaces Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372.8 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Part II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

3 Fundamentals of Autopilot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

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3.2 Primary Subsystems of an Autopilot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493.3 Dynamic Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503.4 UAV Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533.5 Aerodynamic Forces and Moments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543.6 Stability and Control Derivatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563.7 Transfer Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 573.8 State-Space Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 583.9 Linearization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 583.10 Autopilot Design Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603.11 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

4 Control System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 634.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 634.2 Fundamentals of Control Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644.3 UAV Control Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

4.3.1 Control Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674.3.2 Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

4.4 Flight Control Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 704.4.1 Longitudinal Control Requirements . . . . . . . . . . . . . . . . . . . . . . . . 704.4.2 Roll Control Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 724.4.3 Directional Control Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5 PID Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 734.6 Optimal Control-Linear Quadratic Regulator (LQR) . . . . . . . . . . . . . . . . . 734.7 Robust Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 744.8 Digital Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 754.9 Stability Augmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 764.10 Autonomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

4.10.1 Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 794.10.2 Detect (i.e., Sense)-and-Avoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 814.10.3 Automated Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 814.10.4 Fault Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 814.10.5 Intelligent Flight Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824.10.6 Manned-Unmanned Teaming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

4.11 Control System Design Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 834.12 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 864.13 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

5 Navigation System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

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5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.2 Coordinate Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925.3 Inertial Navigation System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925.4 Global Positioning System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 955.5 Position Fixing Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

5.5.1 Map Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 965.5.2 Celestial Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

5.6 Inertial Navigation Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975.6.1 Accelerometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 985.6.2 Gyroscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995.6.3 Airspeed Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1015.6.4 Altitude Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

5.7 Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1035.8 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

6 Guidance System Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1076.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1076.2 Elements of Guidance System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1096.3 Guidance Laws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1116.4 Line-of-Sight Guidance Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1126.5 Formation Flight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1136.6 Proportional Navigation Guidance Law . . . . . . . . . . . . . . . . . . . . . . . . . . . 1166.7 Pursuit Guidance Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1166.8 Waypoint Guidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1176.9 Seeker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1186.10 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

7 Microcontroller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1237.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1237.2 Basic Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1247.3 Modules/Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1277.4 Flight Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

7.4.1 Software Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1307.4.2 Operating System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1317.4.3 Management Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1317.4.4 Microcontroller Programing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1317.4.5 Software Integration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1337.4.6 C Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

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7.4.7 Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1347.4.8 ArduPilot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1347.4.9 Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1357.4.10 Design Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

7.5 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Part III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

8 Ground Control Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1418.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1418.2 GCS Subsystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1428.3 Human Operator in Ground Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1438.4 Types of Ground Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

8.4.1 Handheld Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1458.4.2 Portable GCS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1468.4.3 Mobile Truck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1478.4.4 Central Command Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

8.5 Communication System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1518.6 Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1548.7 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

9 Launch and Recovery Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1579.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1579.2 Fundamentals of Launch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1589.3 Launcher Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1599.4 Recovery Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1619.5 Recovery Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

9.5.1 Parachute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1629.5.2 Impact Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

9.6 Air Launch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1659.7 Hand Launch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1659.8 Launch and Recovery Systems Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1669.9 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1679.10 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

10 Payloads Selection/Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17110.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17110.2 Payload Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17210.3 Cargo or Freight Payload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

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10.4 Reconnaissance/Surveillance Payload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17310.4.1 Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17510.4.2 Radar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

10.5 Scientific Payloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17810.6 Military Payload (Weapon) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17910.7 Payload Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

10.7.1 Payload Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18010.7.2 Payload Aerodynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18110.7.3 Payload-Structure Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18210.7.4 Payload Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

10.8 Payload Control and Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18310.9 Payload Selection/Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . 18410.10 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18510.11 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186

Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

Author Biography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

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PrefaceThe Unmanned Aerial Vehicle (UAV) is a remotely piloted or self-piloted aircraft that can carry cameras, sensors, communications equipment or other payloads. All flight operations (including take-off and landing) are performed without on-board human pilot. In some reports of DOD, Unmanned Aircraft System (UAS) is preferred. In media reports, Drone is preferred. Mission is to perform critical missions without risk to personnel and more cost effectively than comparable manned system.

The contributions of unmanned aircraft in sorties, hours, and expanded roles continue to increase. As of September 2004, some 20 types of coalition UAVs, large and small, have flown over 100,000 total flight hours in support of Operation Enduring Freedom and Operation Iraqi Free-dom. Their once reconnaissance only role is now shared with strike, force protection, and signals collection. These diverse systems range in cost from a few hundred dollars (Amazon sells varieties) to tens of millions of dollars. Range in capability from Micro Air Vehicles (MAV) weighing much less than a pound to aircraft weighing over 40,000 pounds.

The UAV system includes four elements: (1) air vehicle; (2) ground control station; (3) pay-load; and (4) maintenance/support system. The design of manned aircraft and the design of UAVs have some similarities; and some differences. They include the: (1) design process; (2) constraints (e.g., g-load, pressurization; and (3) UAV main components (autopilot, ground station, communica-tion system, sensors, and payload). A UAV designer must be aware of: (a) latest UAV developments; (b) current technologies; (c) known lessons learned from past failures; and (d) designer should appreciate the breadth of UAV design options.

A design process requires both integration and iteration. A design process includes: (1) Syn-thesis: the creative process of putting known things together into new and more useful combina-tions; (2) Analysis: the process of predicting the performance or behavior of a design candidate; and (3) Evaluation: the process of performance calculation and comparing the predicted performance of each feasible design candidate to determine the deficiencies. A designer needs to know how to in-tegrate complex, multi-disciplinary systems, and to understand the environment, the requirements and the design challenges.

The objectives of this book are to review the design fundamentals of Unmanned Aerial Ve-hicles. It will have three Parts and ten Chapters. Part I (Chapters 1 and 2) is on “Vehicle Design” and covers design fundamentals, and design disciplines. This part covers UAV classifications, design project planning, decision making, feasibility analysis, systems engineering approach, design groups,