day2_braking_systems.pdf

7/27/2019 DAY2_Braking_Systems.pdf

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Erasmus LLP Intensive Programme

Powering the Future With Zero Emission and Human Powered Vehicles KdG 2013 1

Brake systems on human

powered vehicle

Subtitle: this is the subtitle of the

presentation



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Your speaker

Mark Pecqueur

Onsiphore Pecqueur (1792 1852)

Professor at KdG University college

Independent expert on Engines and vehicles

More than 18 years active in the world of alternativefuels and drive systems



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Overview

Introduction

Brake process

Brake power

Brake power distribution

The drum brake

The Disc brake

Calculation

Brake energy recuperation systems

Conclusion



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Brake process


tr

v

vtravel

tb tz tcv2v1

Distance

point 1

Point2

Speed


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Brake process


Brake distance

)(11 br ttvs

6

2

max10

2

tzz

t

atvdtvsz

tztata max)(

t

t

t zzavdt

tavtv

2

)(

2

max1max1


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Brake process


Brake distance

tavdtavtv max2max2)(

2max

1

max

2 taa

z

cvvt

max

2

2

2

max203 22 a

vt

atvdtvs

c

c

tc


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Brake process


Brake distance

242)

2(

2max

max

21

1321ta

at zz

brt

vttvssss


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Brake power


Kwt

EP

k

gem36,79

7

56,555 103

Kwt

EP

k

gem36,79

7

56,555 103

t

EP

k

gem

tttatavvE ttm

z

zz

k

2

2

2

maxmax1

2

1 422

2

tm

Pdt

d

taavE

z

k

222

2

maxmax1


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Wr WfW

bc

H


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L

h

gL

cW

aW

x

f

L

h

gL

bW

aW

x

r


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Lh

gLcW aF

x

pxmf

0

1000

2000

3000

4000

5000

6000

7000

8000

a x / g

Fxmf Fxmr


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M

FFa

xrxmf

x

M

FFa

xfxmr

x

L

cWWfs

L

bWWrs

L

h

L

h

p

pxrfsp

xmf

FWF

1

L

h

L

h

p

pxfrsp

xmr

FWF

1


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BXAY

A

B

A

XY

62

XY

122 XY

0

2

4

6

8

10

12

AX+B

X/A-B/A

L

hB

p

rsp W

1

L

hL

h

A

p

p

1


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h

L

L

h

L

h

WFF

rs

p

p

xfxmr

1

L

h

L

h

p

pxrfsp

xmf

FW

F

1 hWL

hWL

RCprs

pfs

W

W


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Brake parameters


w

i

s

FC

F

35,0

rrC wheelbrake

u


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Drum brake


a

a

b

FS

FN

FW

http://auto.howstuffworks.com/auto-parts/brakes/brake-types/drum-brake1.htm


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Drum Brake



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Disk brake


http://auto.howstuffworks.com/auto-parts/brakes/brake-types/disc-brake2.htm


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Conclusions


Fa

Fw

Fw

Fx

)tan(1

)(

)tan(

C

FFF

FF

i

xaw

wX


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Hill decent -3%



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Brake energy recuperation systems


Flywheel?

Battery?

Ultra capacitors?


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conclusion

We do need Brake energy recuperation systems

Disks on the front drum at the rear as main brake

systems

Brake force distribution is not that difficult

Hill decent will be a great challenge



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Thanks

Questions?

Mark Pecqueur

+32 476 40 87 44



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Calculation


Calculate the different dimensions of a brake systems for a human

powered vehicle with a total weight of 150 kg with disk brakes on the front

wheels and a drum brake at the rear wheel together with a hydraulic brake

systems.

The maximum force on the brake is 120N with a diameter of the wheels of

42 cm. The center of gravity is at a height of 44 cm in the middle vehicle

with a wheelbase of 1,8 m.

Calculate the diameter of the brake disks, diameter of the brake cylinder,

diameter of the drum brake diameter of the brake cylinder

day2_braking_systems.pdf

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