pace team 1 pamd presentation july 2013

Team structure / Collaboration process

Design concept / User scenario / Positioning map /

Folding system / Modular structure / Docking system /

Customizing / Mock-up process

Project management / Target market

Business plan / Marketing strategy /

Carbon footprint / Plant safety

Collaboration / Overall / Powertrain / Stability /

Frame / Driving / Module /

Vehicle Technical Specification

Contents

2

01 Team structure

4

01 Team structure

5

01 Team structure

6

01 Team structure

7

01 Team structure

8

01 Team structure

9

01 Team structure

10

01 Team structure

11

02 Process(January 2013~)

12

02 Process (January 2013~)

13


14


15


16


18


19


20


21

01 Design concept

23

01 Design concept

24

01 Design concept

26

01 Design concept

27

01 Design concept

28

01 Design concept

29

02 User scenario

30

02 User scenario

31

02 User scenario

32

02 User scenario

33

01 Design concept

34

Price

Weight

03 Positioning map & Package

36

Price

Weight


37


38

04 Folding system

40

04 Folding system

41

05 Modular structure

42

05 Modular structure

43

06 Customizing

44

06 Customizing

45

06 Customizing

46

handle

06 Customizing

47

06 Customizing

48

06 Customizing

49

07 Docking system / Smart application

51

07 07 Docking system / Smart application

52

07 Docking system / Smart application 07 Docking system / Smart application

53


54


55


56


57


58


59


60


61


62


63


64

08 Mock-up process

66

08 Mock-up process

67

08 Mock-up process

68

08 Mock-up process

69

08 Mock-up process

70

01 Project management

72

02 Target market

73

02 Target market

74

02 Target market

75

02 Target market

76

02 Target market

77

02 Target market

78

02 Target market

79

02 Target market

80

02 Target market

81

02 Target market

82

02 Target market

83

02 Target market

84

02 Target market

85

02 Target market

86

Driving

Brake Suspension

Powertrain

Motor Battery

Frame

Ergonomics Material selection Structure design Folding mechanism

01 Overall

Stability

Pitching direction Roll direction

88

02 Powertrain

36 V & 300 W in front wheel Weight 3 kg Fork size 14 cm Wheel diameter 30 cm

Powertrain

BLDC Hub motor

89

Traction force & Total running resistance

Slope (deg)

Power

Velocity (km/h)

Tra

ction fo

rce / T

ota

l runnin

g re

sistance

(kgf) Motor power : 300 W

Target Maximum speed : 10 km/h at 10% (6˚) uphill

02 Powertrain - Motor

Weight of STIGO: 12 kgf Weight of user : 75 kgf Air density : 1.205 kg/m^3 Frontal area : 1.1 m^2 Drag coefficient : 0.7 Rolling resistance coefficient : 0.01

90

Weight of STIGO: 12 kgf Weight of user : 75 kgf Viscosity of the air : 1.86*10^-6 kg/m-s Driveway slope : 6 degrees Driving speed : 10 km/h

300 W is enough


Verification by simulation

91

Type : BLDC hub motor

Power : 300 W

Voltage : 36 V

Torque : 14 N-m

Maximum Speed : 280 RPM

Weight : 3 kg

Fork size : 14 cm 14 cm

30 cm

14.8 cm


Specifications Location

92

Powertrain

Powertrain – Battery pack 02 Powertrain

Battery Pack

Li-ion Battery 36 V 5000 mAh / 180 Wh 22.8 x 12 x 3.8 (cm)

93

Supposing

75%

25% Walking time

Time of using

Public transportation

Average commuting Time (OECD)

35 min.

Target hour: 1 hour usage available (at 15 km/h)

02 Powertrain – Battery Pack

Target

x

Use STIGO (25%)

0.25

Round trip

2 x x

Safety factor

3

= 53 min.

94

1.7 kg

228 mm

120mm

38mm Type : Li-ion Battery pack

Capacity : 180 Wh

# of cell : 40

Type : LiFePO4

Voltage : 3.2 V

Capacity : 1400 mAH

Mass : 40 g

Battery Cell

02 Powertrain – Battery Pack

Specification Location

95

Stability

03 Stability

Stability in Roll direction Depends on driver’s position

Consideration about changing footrest position

Stability in Pitching direction Depends on distance between 2 rear wheels

Consideration about adopting tilting system

96

: Footrest positioned on rear wheel axis

Total weight : 87 kgf Driveway slope : 6 deg. Torque of Motor: 32.5 N-m Friction coefficient : stat. 0.9 / kin. 0.8

Footrest position

↑Graph of STIGO’s pitching angle

Stability test of baseline model

03 Stability – Pitching direction

97

Total weight : 87 kgf Driveway slope : 6 deg. Torque of Motor: 32.5 N-m Friction coefficient : stat. 0.9 / kin. 0.8

↑Graph of STIGO’s pitching angle

Footrest position

03 Stability – Pitching direction

Stability test of improved Model : Footrest was moved to forward 200 mm from rear wheel axis

98

A

Centrifugal force

Rollover

Rollover criteria :

(total mass) : 90 kg (user height) : 1.8 m (diameter of back wheel) : 7 in. (distance between 2 wheels) : 15 cm (acceleration of gravity) : 9.8 m/s2

(curve radius) : Variable driving speed : Variable (tilting angle) : Variable (sum of moments) : Output

03 Stability – Roll direction

Modeling

Moment equation in roll direction

+

99

An example of motor tricycle applied tilting system

No tilting STIGO Tilting STIGO (up to 10˚)

* For the sake of convenience, the right table is calculated at only 10˚, not 0~10˚ .


Stability analysis & Test

Centrifugal force

: No tilting STIGO

: Tilting STIGO (up to 10˚)

Total weight : 90 kgf STIGO height : 1.863 m (including human height) Curve radius : 3 m Driving speed : 5 km/h Tilting STIGO’s angle : 7 ˚

Top view

Back view

both Stable(not rollover).

3m radius curve at 5km/h,

100

An example of motor tricycle applied tilting system



3m radius curve at 9.5 km/h, 9.5

No tilting STIGO turns over.

Centrifugal force

: No tilting STIGO

: Tilting STIGO (up to 10˚)

Total weight : 90 kgf STIGO height : 1.863 m (including human height) Curve radius : 3 m Driving speed : 9.5 km/h Tilting STIGO’s angle : 10 ˚

Top view

Back view



101



Tilting of just small degrees

(10deg.)

Improving stability of rollover direction considerably

SAFE ZONE

SAFE ZONE



102

Tilting of just small degrees

(10deg.)

Improving stability of rollover direction considerably

If an user tilts their body slightly,

It doesn’t need tilting system!



103

Baseline Model Improved Model

Stability

Analysis

Change footrest position

No tilting system

03 Stability

Conclusion of stability analysis

104

Ergonomics The height of handle bar

The shape of footrest

Frame

04 Frame

105

Less side force in user’s knee

74 ~ 125 cm

04 Frame - Ergonomics

The height of handle bar The shape of footrest

The sloping bottom

Less arm fatigue

Average 100 cm height position

106

Aluminum 6061 Butted tube FRP body case

Material

04 Frame

Frame

107

Aluminum 6061 in the body frame.

04 Frame - Material

Material Selection Good Normal Bad

108

Aluminum 6061

Yield strength : 255 MPa

Safety factor : 3

Type Pipe-shape tube Butted tube

Mass 0.3 kg 0.143 kg

Max stress

Compressive force

Bending force

5.437 MPa

60.36 MPa

13.61 MPa

84.15 MPa

52.33% of the mass is reduced.

04 Frame - Material

Frame tube design

109

04 Frame - Material

Fix

Fix

150 x 3 = 450N

600 x 3 = 1800N

Material Analysis for footrest

[ load and boundary conditions] Safety factor : 3

Max Stress : 169.01 MPa < Yield stress(255 MPa)

Safe 110

Frame

04 Frame

Folding mechanism Motivated by umbrella

Folding footrest

111

Umbrella

04 Frame – Folding mechanism

Motivation

One-step folding

Easy to use

Stability

112


Connecting bar

113

x = 12 cm

F = 625 N

x position – tension force graph

of connecting bar

Upper position of connecting bar

Designer preferred for beauty

Lower position of connecting bar

Engineer preferred for safety

Compromised position x 12 cm

Position of connecting bar


114

Possible cross section shapes

Staple shape

Round shape

Window shape

Shape of connecting bar’s cross section


115

[Case 2] : Footrest coming out from the frame

[Case 1] : Unfolding footrest coming out in the case


Footrest folding mechanism

[Case 2] : Footrest coming out from the frame

116

Footrest : Enough length to ride (18 cm)

Footrest-Rod : Enough length to fold (28 cm)

Footrest-Stay : Enough space to fold (32 cm)

Footrest folding mechanism


117

Safety factor : 3


Improved design 2 Baseline design 1

23.30MPa < Yield strength (O)


2747.49MPa < Yield strength (X)



FEA results of footrest

218.47MPa < Yield strength (O) Yield strength : 255MPa, 118

Driving

05 Driving

Suspension Spring coefficient 33,000 kN/m Damping coefficient 300 N·s/m

Mechanical disk brake Suitable for BLDC motor

119

Bra

ke

Caliper Cantilever V-brake Mechanical Hydraulic

Str

ength

s

Light weight Low price High braking

power

Low price Easy of repair and

maintenance Suitable for BLDC

MOTOR

High braking power

Weakness

es

Low braking power Hard to set up Moisture effect Difficulty to handle

at steep slope

High price Difficult of repair and maintenance

05 Driving - Brake

Brake requirement Mechanical disk brake

Suitable for BLDC Motor

Easy to set up

Reasonable price

Braking power

120

“First Mile/Last Mile Transition” Rough road

For better comfortable driving

05 Driving - Suspension

121

Comfortable driving

SUSPENSION


For better comfortable driving

K : 33,000 N/m C : 300 N·s/m

122

Design part

Analysis part 1. Position of Suspension? 2. Angle of Suspension? 3. Enough space for suspension?

Simulation with ADAMS tool


Collaboration

123

VS

Case 1-1 Front wheel

Case 1-2 Connecting bar


1. Where should the suspension is located in?

• Comfortable ride : 1~1.5 [Hz]

• Excitation frequency : 0.05Sin(𝟒𝝅𝒕)

• Amplitude : 5 [cm]

• Frequency : 2 [Hz]

• Spring coefficient (k)

33000 [N/m]

• Damping coefficient (c)

300 [N•s/m]


Suppose that…

Leng

th(m

m)


Case

1 F

ront w

heel

Case

2 C

onnectin

g b

ar angle of frame suspension displacement

Len

gth(

m)

suspension displacement

BUMP

BUMP


Case 1-1 Front wheel

Case 1-2 Connecting bar

1. Where should the suspension is located in?

Case 2-2 Tilted suspension

VS

Case 2-1 Vertical suspension

2. Which angle of suspension is suitable?



Case

1 V

ertica

l Case

2 T

ilted

Unstable


Case 2-2 Tilted suspension

Case 2-1 Vertical suspension

2. Which angle of suspension is suitable?

Overlap with wheel

Overlap with frame


3. Does STIGO have enough space for suspension?


Final STIGO with suspension

Space for length of suspension

Space for radius of suspension

Enough space for suspension Final model


Without Suspension Final STIGO with suspension

Conclusion


With

out su

spensio

n

Optim

ized su

spensio

n

• Need suspension because STIGO passes rough road. In case of STIGO with suspension, expect a comfortable ride.

Improved the ride quality !

• Simulate vibration characteristic of STIGO with suspension by ADAMS tool.

• To apply suspension, consider two position. And Change angle at determined position. Finally, To apply actual suspension, consider space problem.

• As compared with STIGO without suspension, improved performance in case of STIGO with suspension.

Conclusion


Module

06 Module

Saddle 5~95% human available Contained extra battery

136

06 Module - Saddle

Concept

Saddle concept

Extra battery concept

137

Target value: 60.0°, Radius: 50.48 cm

Saddle movement path

06 Module - Saddle

Considering 5 ~ 95%

human model

138

Pressure measurement image 3D Model

06 Module - Saddle

139

07 Collaboration

Engineers

Designers

140

07 Collaboration

Main issue

Weak connection

Unstable footrest

Frame structure

141

07 Collaboration

Final concept

Strong connection

Stable footrest

Frame structure

142

Rear rubber tire

Non-slip step pads HIPS plastic

Aluminum main frame Strength, lightweight and flexibility

LED Back light High visibility for increased safety

NBR Handle cover Comfortable grip

Battery Pack Li-ion 36V 180Wh

Front aluminum rim Strength and rigidity

Front rubber tire

FRP case Lightweight, low-thermal expansion and strength

LED Front light High visibility for wide

view and increased safety

Rear aluminum rim Strength and rigidity

Footrest Strength and rigidity

Smartphone dock system

Hub motor 36V 300W in front wheel

Stop lever Eidetic plastic lever for increased safety

Controller

Steering Bevel gear assembly

for steering

Suspension

Materials Components

07 Vehicle Technical Specifications

143


Speed

Adjustable from 2 to 15 km/h

Motor BLDC Hub Motor 36V, 300W in Front Wheel

Max. endurable load 110kg

Climbing ability 10% continuous at 10km/h

Range on a full charge 1hour, 15km

Battery pack

Li-ion built-in BMS(Battery Management System) LiFePO4, 180 Wh, 1.7 kg

Brake Mechanical disk brake

Suspension Front wheel

Spring 33 kN/m, Damp 300N-s/m

Steering Bevel gear assembly

144


Weight 12.7 kg

Ground clearance 6.3 cm

Wheels diameter Front : 30 cm / Rear : 17.8

cm

Frame

Aluminum 6061

Grips NBR

Body case FRP

Open STIGO dimension Length: 90 cm Width: 44.6 cm Height: 103 cm *Except handlebar Width

Folded STIGO dimension Length: 33.5 cm

Width: 30.2cm Height: 117.8 cm

*Except handlebar Width

145

01 Business plan

147

01 Business plan

148

01 Business plan

149

01 Business plan

150

01 Business plan

151

02 Marketing strategy

152


153


154

03 Carbon footprint

155

04 Plant safety

156

pace team 1 pamd presentation july 2013

Technology

folding system

tilting system

target hour

kgf weight of user

w target maximum speed

stability stability

powertrain bldc hub

wheel weight