Kaleo Norman & Joshua Shigemitsu

Until recently, UAV’s have been used primarily in military applications.

However technology and the application of the UAV is quickly evolving into a

tool that can be used in civil, commercial, and other STEM disciplines. By

utilizing the aerial surveillance that the UAV offers, it provides a clean energy

alternative for civil applications such as: search and rescue, real time

weather updates, gathering research data and creating aerial maps. With

these examples in mind this project was undertaken to provide a real life

application for students by allowing them to design and built a UAV. By

creating this prototype, it can be shown that UAV technology can directly

benefit civil and commercial industries. For the application of this project, a

UAV was built with the purpose of surveying farmland by taking aerial images

and recording GPS coordinates.

Introduction

The Engineering Design Process

• Brainstorm- How to survey a large area of land with rough terrain?

• Research- Identifying types of aircraft that could be used,

understanding the parts of an airplane, the principles of flight, and

locating the plane’s center of gravity. Perform a Quality Function

Deployment (QFD) prioritizing quality demands (See Figure 2).

• Design- what features were going to be on the UAV? A QFD showed

that a flying wing was the best platform suited towards our needs. UAV

needed to be able to fly autonomously, show first-person view, and be

easy for the user to handle.

• Analyze- Perform a finite elements analysis to test the force on certain

parts and determine if parts were safe to use. (See Figure 1)

• Build- UAV is constructed out of Expanded Polypropylene Foam.

• Test- Aircraft went under several test flights. High definition video and

film was recorded for land monitoring purposes.

Engineering Specifications

Demanded Customer Quality Weight / Importance

(Scale 1-5)

Relative

wt (%)

Autonomous 5 16.7 9 7 9 3 3 7 7 7 7 8 1 5

See things with the plane 5 16.7 3 7 2 2 9 6 8 7 2 5

Carry things 2 6.7 3 8 7 9 9 3

Fly fast 3 10.0 7 7 7 8 7 8 9 9 6 4 7

Fly for a long time 4 13.3 6 2 9 7 3 6 6 8 7

Easy to use 5 16.7 8 7 4 9 6 6 6 5 5 9

Durability 4 13.3 6 9 1 4 4 6 7 8 3 7 8

Cost 2 6.7 7 8 2 8 4 7 6 7 5 8 5 9

100.0

6 2yr 430MHZ 400 W 20c 1080p 20m/s 1m/s 2500m 2km 5kg $2,500

H H L L L H H H H H L L

## 188 117 133 118 199 200 124 189 128 140 200

9.4 12.2 7.6 8.6 7.7 12.9 13.0 8.1 12.3 8.3 9.1 13.0

5 4 10 6 9 2 1 8 3 7 6 1

Range

Cost

Sensors

Serv

ice Life

Fre

quency

Pow

er

Consum

ption(W

atts)

Dis

charg

e / R

echarg

e r

ate

Ima

ge

Qu

ality

Mass

Rank

Target

High or Low

Specification weight

Relative weight

Airspeed

Clim

b R

ate

Altitude

QFD

Research

Fabrication

The airframe was made out of Expanded Polypropylene Foam and

compartments were made to house the electronic systems. The

electronics included the control systems, the autopilot (Ardupilot Mega),

and the batteries. Two lithium polymer rechargeable batteries were used

to power the plane. The frame was then laminated to increase durability.

The elevons, which are the control surfaces, were made out of balsa

wood and then laminated. The brushless motor has a folding propeller

and was mounted on the back of the UAV.

Results The UAV underwent several test flights and then was successfully flown

at the farm. High definition video was then downloaded from the UAV

and used to provide a valuable bird’s eye view of the banana crop. In

the future, the UAV will be programmed to fly a set pattern so that the

crops can be surveyed systematically, and on a regular basis.

Mentors: Dr. Mehrdad Nejhad, Michael Menendez, David Hummer

University of Hawai`i at Mānoa College of Engineering

A computer aided design program called SolidWorks was used to design

the parts of the UAV and then assemble them all into one drawing. Another

part of the design was utilizing Finite Element Analysis, (FEA). This was

used to test the force on certain parts and determine if the parts are safe to

use. The minimum factor of safety greater than 1. The motor mount of the

UAV (See Figure 1) was analyzed and received a factor of safety of 14.

Design

Fig: 1 Stress Analysis

Fig: 2 Quality Function Deployment