无人机专业英语课件：flight dynamics of uav

无人机专业英语

Flight

Dynamics

of

UAVFlight

Dynamics

of

UAV1C

O

N

T

E

N

T

2

Control

Surfaces3.13.2The

three

critical

flight

dynamics

parameters

of

fixed-wing

drone

aretheangles

of

rotation

in

three

dimensions.The

center

point

is

called

center

ofgravity(COG),being

the

origin

of

three

axes

in

the

meantime.Three

axesare

normal

axis,longitudinal

axis,and

lateral

axis.Rotations

in

threedimensionsareyaw,roll,and

pitch,respectively.Movement

of

YawNormal

Axis

of

AircraftFlight

Dynamics

of

UAVAxis

and

Rotation3.13.1.1Roll

is

the

rotation

about

the

longitudinalwing

down.Flight

Dynamics

of

UAVLongitudinal

Axis

ofAircraftwith

the

starboardAxis

and

Rotationaxis,positiveMovement

of

Roll3.13.1.1Pitch

is

the

rotation

about

the

lateral

axis,positive

with

nose

up.

Movement

of

PitchLateral

Axis

of

AircraftFlight

Dynamics

of

UAVAxis

and

Rotation3.13.1.1Aerodynamic

forces

are

highly

dependent

on

the

interaction

of

theatmosphere

molecules

with

the

aircraft

surface,and

specifically

on

themolecules’density

and

velocity.Here

the

velocity

refers

to

the

relativevelocity

between

atmosphere

and

aircraft.Aerodynamic

Forces

on

an

AircraftFlight

Dynamics

of

UAVAerodynamic

Forces3.13.1.2A

cross

section

of

a

typical

airplane

wing

shows

the

top

surface

to

bemore

curved

than

the

bottom

surface.This

shaped

profile

is

called

an

“airfoil”and

the

shape

existsbecauseithaslongbeenproven(sincethedawnofflight)that

an

airfoil

generates

significantly

more

liftthanopposingdrag.AirfoilFlight

Dynamics

of

UAVAirfoil3.13.1.3The

faster

a

wing

moves

through

the

air,the

more

the

actions

are

exaggerated

andthemoreliftis

generated.Conversely,a

slower

moving

wing

generally

creates

less

lift.The

lift

equals

to

half

of

the

density

times

the

square

of

velocity

times

wing

areatimes

lift

index.The

Generation

of

LiftFlight

Dynamics

of

UAVThe

Generation

of

Lift3.13.1.3For

a

airplane

to

fly

in

a

controlled

manner,control

surface

are

necessary.The

four

main

surfaces

are

aileron,elevator,rudderandflap.When

the

airplane

is

in

forward

flight,it

will

rotate

around

each

axiswhen

movement

to

any

control

surface

is

made

by

the

operator

or

flightcontroller.Control

SurfacesControl

Surfaces3.2Provide

evidence

to

support

arguments.The

structure

of

well-organized

paragraphs.T

o

pic3

.3Unit

3

English

Training

Partof

a

paragraph

.CoherenceT

o

pic

3

.1T

o

pic

3

.2A

paragraph

is

a

series

of

sentences

that

are

organized

and

coherent,

and

are

all

related

to

a

single

topic

.

Paragraphs

can

contain

many

different

kinds

of

information

.

A

paragraph

could

contain

a

series

of

brief

examples

or

a

single

long

illustration

of

a

general

point

.

It

might

describe

a

place,

character,

or

process;

compare

or

contrast

two

or

more

things

;

classify

items

into

categories

;

or

describe

causes

and

effects

.

Regardless

of

the

kind

of

information

they

contain,

all

paragraphs

share

certain

characteristics

.

One

of

the

most

important

of

these

is

a

topic

sentence

.The

structure

of

w

ell

-

organized

paragraphs

.To

p

i

c3.

1All

university

research

and

scholarship

is

based

on

evidence,

and

your

own

assessed

work

as

a

student

is

no

different

.

To

convince

your

marker

that

you

know

what

you’re

talking

about,

you

can’t

just

make

a

statement

and

expect

them

to

accept

it

;

you

will

need

to

provide

robust

evidence

to

justify

your

point,

show

how

you

have

arrived

at

your

conclusions

and

prove

that

it’s

based

on

solid

grounds

.Provide

evidence

to

support

arguments

.To

p

i

c3

.2•Repeat

key

w

ords

or

phrases

.

Particularly

in

paragraphs

in

w

hich

you

define

or

identify

an

important

idea

or

theory,

be

consistent

in

how

you

refer

to

it

.•Create

parallel

structures

.

Parallel

structures

are

created

by

constructing

tw

o

or

more

phrases

or

sentences

that

have

the

same

grammatical

structure

and

use

the

same

parts

of

speech

.

By

creating

parallel

structures

you

make

your

sentences

clearer

and

easier

to

read

.•Use

transition

words

or

phrases

between

sentences

and

between

paragraphs

.

Transitional

expres