Design and Validation of the Unsprung Masses of a Formula SAE vehicle

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POLYTHECNIC OF TURIN

Department of Mechanical and Aerospace Engineering Master of Science in AUTOMOTIVE ENGINEERING

Thesis Project

Design and Validation of the Unsprung Masses of a Formula SAE vehicle

Supervisor Candidate

Prof. Andrea Tonoli Luis Daniel Medina Querecuto

April 2020

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ABSTRACT

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ACKNOWLEDGEMENTS

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TABLE OF FIGURES

“ ”

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LIST OF TABLES

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INTRODUCTION

i. Context and motivation

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5

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ii. Problem Statement

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iii. Aim and Objectives

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iv. Delimitation

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v. Method and processes

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Sep-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18

1- 2017 season outcome 2- 2018 target setting 3- Recruitment 4- Budget and partners definition 5- PRELIMINARY DESIGN 5.1- Veichle dynamics 5.2- Battery pack 5.3- Packaging 6- DESIGN 6.1- System-level analyses 6.2- CAD modelling and simulation 7- PROTOTYPING, TESTING AND VALIDATION 8- COLLABORATIVE DEVELOPMENT 9- PRODUCTION 9.1- Components sourcing 9.2- Lamination 9.3- Machining 9.4- PCB production 9.5- Wiring 10- CAR ASSEMBLY 11- BENCH TEST AND DEBUGGING 12- TRACK TESTS 12.0- Track tests on SC17 12.1- Reliability tests 12.2- Installation laps 12.3- Dynamic events simulation 13- FSAE Italy

14- Tack tests 15- FSS Spain

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vi. Background and literature review

𝜇_𝑥 =^𝐹^𝑥

𝐹_𝑧

𝜇_𝑦=^𝐹^𝑦

𝐹_𝑧

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𝑆𝑅 =^𝛺−𝛺⁰

𝛺₀

𝛺 𝛺₀

α

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vii. Unsprung Mass

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viii. Role of the unsprung mass in vehicle performance

Road holding

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𝜔_𝑢𝑠= √^𝐾_𝑚^𝑠^+𝐾^𝑡

𝑢𝑠

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Suspension geometry

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ix. Yaw inertia

𝐼_𝑍𝑍= 𝐼_𝑧𝑧+ 𝑚 𝑑²

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𝑀_𝑧 = 𝐽_𝑧𝜓̈ = 𝐹_𝑦𝑓𝑎 − 𝐹_𝑦_𝑟𝑏 +¹

2𝐶_𝑀_𝑧𝑆𝜌𝑉²

𝜓̈

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𝛽

𝛼_𝑖 𝑟

𝑚𝑉(𝛽̇ + 𝑟) + 𝑚𝑉̇𝛽 = 𝑌_𝛽𝛽 + 𝑌_𝑟𝑟 + 𝑌_𝛿𝛿 + 𝐹_𝑦𝑒 𝐽_𝑧𝑟̇ = 𝑁_𝛽𝛽 + 𝑁_𝑟𝑟 + 𝑁_𝛿𝛿 + 𝑀_𝑧𝑒

𝑌_𝛽 𝑌_𝑟 𝑌_𝛿 𝑁_𝛽 𝑁_𝑟 𝑁_𝛿 𝐹_𝑦𝑒

𝑀_𝑧𝑒

𝑃𝑟̈ + 𝑄𝑟̇ + 𝑈𝑟 = 𝑆^′′𝛿 + 𝑇^′′𝛿̇+ 𝑁_𝛽𝐹_𝑦𝑒− 𝑌_𝛽𝑀_𝑧𝑒+ 𝑚𝑉𝑀̇_𝑧𝑒 9

𝑃 = 𝐽_𝑧𝑚𝑉 𝑆^′′= 𝑌_𝛿𝑁_𝛽− 𝑁_𝛿𝑌_𝛽

𝑄 = −𝐽_𝑧𝑌_𝑏− 𝑚𝑉𝑁_𝑟 𝑇^′′= 𝑚𝑉𝑎𝐶₁ 𝑈 = 𝑁_β(𝑚𝑉 − 𝑌_𝑟) + 𝑁_𝑟𝑌_𝛽

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x. Thermal capacity of brake rotors and calipers

Δ𝐸_𝑏 =^𝑚₂(𝑉₁²− 𝑉₂²) +^𝐼

2(𝜔₁²− 𝜔₂²) − 𝐹_{𝑑𝑟𝑎𝑔}𝑑_{𝑏𝑟𝑎𝑘𝑒}

𝑚 𝐼 𝑉

𝜔

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𝛥 𝑇 =

^𝐸^𝑏𝑖^𝑝

𝑚_{𝑑𝑖𝑠𝑐}𝐶_𝑝 𝐸_𝑏_𝑖

𝑖 𝑚_{𝑑𝑖𝑠𝑐} 𝐶_𝑝

𝑝

𝐵𝑖 =

^ℎ𝐿^𝑐

𝑘

≪ 0.1

ℎ 𝑘

𝐿_𝑐

𝐹𝑜 =

^𝛼𝑡

𝐿_𝑐²

𝛼 𝑡

𝑇−𝑇_∞

𝑇_𝑖−𝑇∞

= 𝑒

^{−𝐵𝑖⋅𝐹𝑜}

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𝑖

xi. PoliTo Racing 2018

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CHAPTER 1. PROJECT DEFINITION

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End of 2017 season

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1.1 Evaluation of the 2017 season

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PROS CONS Good mechanical reliability

Adequate battery pack capacity Flexibility in suspension configuration Adjustable aerodynamic package

Excessive weight and inertia Sub-optimal use of the tire forces

Low downforce compared to competitors Excessive steering compliance

Difficult maintenance

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1.2 Top-Level Concept definition and target setting

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1.2.1 Requirements and targets for systems involving unsprung components

𝑁𝑚 𝑟𝑎𝑑

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Additional competition regulations

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Tilt test

Brake test procedure

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1.2.2 Results from the preliminary analyses

1.2.2.1 Suspension geometry and loads

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1.2.2.2 Transmission envelope

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1.2.2.3 SC17 brakes performance

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1.2.2.4 Steering system

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CHAPTER 2. DESIGN PHASE

2.1 Brakes system design

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2.1.1 Possibilities for weight saving on the brake calipers

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★ ★★★★★ ★★★★★ ★★ ★★★★★ ★★★★★

★★★★ ★★★★ ★★★★ ★★★ ★★ ★★★

★★★★★ ★★★★ ★★★ ★★ ★ ★★

★★★ ★★★★★ ★★★★★ ★★ ★★★★ ★★★★★

2.1.2 Brake caliper selection

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𝐹𝑧_{1𝑏𝑟𝑎𝑘𝑒𝑑} = 𝐹𝑧_{1𝑠𝑡𝑎𝑡𝑖𝑐}+ Δ𝐹𝑧 𝐹𝑧_{2𝑏𝑟𝑎𝑘𝑒𝑑} = 𝐹𝑧_{2𝑠𝑡𝑎𝑡𝑖𝑐}− Δ𝐹𝑧

Δ𝐹𝑧

Δ𝐹𝑧 = 𝑚𝑎_𝑥(^ℎ^𝐶𝐺

𝑙 )

𝑎𝑥 ℎ𝐶𝐺

𝑙

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Δ𝐹𝑧 𝐹𝑧_{1𝑏𝑟𝑎𝑘𝑒𝑑} 𝐹𝑧_{2𝑏𝑟𝑎𝑘𝑒𝑑} 𝐹_𝑥₁ 𝐹_𝑥₂

𝑖

𝑇

_{𝑏𝑟𝑎𝑘𝑒}_𝑖

=

^𝐹^𝑥𝑖

2

𝑅

_𝑙_𝑖 𝑅_𝑙

𝑝𝑙𝑖𝑛𝑒_𝑖=𝑇_{𝑏𝑟𝑎𝑘𝑒𝑖} 𝑟_{𝑝𝑎𝑑𝑖}

⋅

_𝐴 ¹

𝑐𝑖𝜇_{𝑝𝑎𝑑𝑠𝑖} 𝑟_𝑝𝑎𝑑

𝑟_𝑝𝑎𝑑

𝐴𝑐

𝜇_{𝑝𝑎𝑑𝑠}

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0 200 400 600 800 1000 1200

0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0

P4 32/26 P4 30/34 P4 26/28 P4 24 P2 24 P4-24 P2-24

Front Axle Rear Axle

Mass [g]

Pressure [bar ]

Mass Pressure (best case) [bar] Pressure (worst case) [bar]

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0.3 0.4 0.5 0.6 0.7 0.8 0.9

0 50 100 150 200 250 300 350 400 450

Friction Coefficient

Temperature [°C]

Z04 CC SA LA RC SC

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2.1.3 Load distribution study

𝐹

_{𝑝𝑒𝑑𝑎𝑙}

𝐾

_𝑏

=

^𝑇^brake1

𝑇_brake2

=

𝐹pedal 𝐴MC1× ^𝑙2

𝐿bar×𝑟_pad1×𝐴_𝐶1×𝜇_{𝑝𝑎𝑑𝑖} 𝐹pedal

𝐴MC2× ^𝑙1

𝐿bar×𝑟_pad2×𝐴_𝐶2×𝜇_{𝑝𝑎𝑑𝑖} 𝐴_𝑀𝐶₁ 𝐴_𝑀𝐶₂

𝐿_𝑏𝑎𝑟

𝑙₁ 𝑙₂

𝐾

_𝑏

= (

^𝑙²

𝑙₁

) (

^𝐴^MC2^×𝑟^pad1^×𝐴^𝐶1

𝐴_MC1×𝑟_pad2×𝐴_𝐶2

)

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%𝐹𝑟𝑜𝑛𝑡 𝐵𝑖𝑎𝑠 =

^𝑙²

𝐿_𝑏𝑎𝑟

× 100

𝐹𝑥

₂_{𝑟𝑒𝑎𝑙}

=

^𝐹𝑥^{1𝑖𝑛𝑝𝑢𝑡}

𝐾𝑏

(𝐹𝑥1_{𝑖𝑛𝑝𝑢𝑡}− 𝐹𝑥2_{𝑖𝑑𝑒𝑎𝑙}) = 𝜇𝑥(𝑚 𝑔

𝑙 (𝑏 − 𝑎 + 𝜇𝑥 2 ℎ𝑐𝑔) + (𝐹𝑧_{𝑎𝑒𝑟𝑜1}− 𝐹𝑧_{𝑎𝑒𝑟𝑜}₂) −2 𝐹_{𝑑𝑟𝑎𝑔} ℎ_𝑐𝑔

𝑙 +2𝜇_𝑥(𝐹𝑧𝑎𝑒𝑟𝑜₁+ 𝐹𝑧_{𝑎𝑒𝑟𝑜2}) ℎ𝑐𝑔

𝑙 )

𝜇_𝑥 = ^𝐹𝑥^{1𝑖𝑛𝑝𝑢𝑡}^+𝐹𝑥^{2𝑖𝑑𝑒𝑎𝑙}

𝑚𝑔+𝐹𝑧_{𝑎𝑒𝑟𝑜1}+𝐹𝑧_{𝑎𝑒𝑟𝑜2}

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𝐹𝑧_{𝑎𝑒𝑟𝑜𝑖} =¹

2𝜌_𝑎𝑖𝑟𝐶_𝑧_𝑖𝑆𝑉² 𝐶_𝑧₁𝑆 𝐶_𝑧₂𝑆 𝐹𝑥₂_{𝑖𝑑𝑒𝑎𝑙}

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𝐾_𝑏

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2.1.3.1 Proportional valve

•

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•

2.1.3.2 Effects of Regenerative Braking

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2.1.4 Brake rotors design

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2.1.4.1 Determining the energy converted into heat by the brake rotors

Φ =

^𝐹^𝑥2

𝐹_𝑥2+𝐹_𝑥1

𝑉_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙} 𝑉_{𝑓𝑖𝑛𝑎𝑙}

Δ𝐸

_𝑏₁

= (1 − Φ) (

^𝑚

2

(𝑉

_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}²

− 𝑉

_{𝑓𝑖𝑛𝑎𝑙}²

) − 𝐹

_{𝑑𝑟𝑎𝑔}

𝑑

_{𝑏𝑟𝑎𝑘𝑒}

) +

^𝐼¹

2

(

𝜔_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}² − 𝜔_{𝑓𝑖𝑛𝑎𝑙}²

)

Δ𝐸

_𝑏₂

= Φ (

^𝑚

2

(𝑉

_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}²

− 𝑉

_{𝑓𝑖𝑛𝑎𝑙}²

) − 𝐹

_{𝑑𝑟𝑎𝑔}

𝑑

) +

^𝐼¹

2

(

𝜔_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}² − 𝜔_{𝑓𝑖𝑛𝑎𝑙}²

)

𝑑𝑏𝑟𝑎𝑘𝑒 𝑎𝑥

𝑑

=

^𝑉^{𝑓𝑖𝑛𝑎𝑙}

2 −𝑉_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}² 2𝑎_𝑥

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𝐹

_{𝑑𝑟𝑎𝑔}

=

¹

2

𝜌

_𝑎𝑖𝑟

𝐶

_𝑥

𝑆 (

^𝑉^{𝑖𝑛𝑖𝑡𝑖𝑎𝑙}^+𝑉^{𝑓𝑖𝑛𝑎𝑙}

2

)

2

𝐸_𝑏 Φ 𝑎_𝑥 𝑉_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙} 𝑉_{𝑓𝑖𝑛𝑎𝑙} 𝐶_𝑥𝑆

𝑝

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2.1.4.2 Thermal analysis of the brake rotors

𝑝 =

√(𝑘_{𝑑𝑖𝑠𝑐} 𝐶_𝑝_{𝑑𝑖𝑠𝑐} 𝜌_{𝑑𝑖𝑠𝑐}) 𝑆𝑑𝑖𝑠𝑐

√(𝑘_{𝑑𝑖𝑠𝑐} 𝐶_𝑝_{𝑑𝑖𝑠𝑐} 𝜌_{𝑑𝑖𝑠𝑐}) 𝑆_{𝑑𝑖𝑠𝑐}+ √(𝑘_{𝑝𝑎𝑑𝑠} 𝐶_𝑝_{𝑝𝑎𝑑𝑠} 𝜌_{𝑝𝑎𝑑𝑠}) 𝑆_{𝑝𝑎𝑑𝑠}

ρ

𝑑𝑖𝑠𝑐 𝑝𝑎𝑑𝑠

𝑃 =

^𝑑(𝐸^𝑏𝑖⁾

𝑑𝑡

𝑃_𝑖(𝑡)= 𝑇_{𝑏𝑟𝑎𝑘𝑒}⋅ 𝜔_𝑖(𝑡)

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Δ𝑇 = (𝑇

⋅ 𝜔

_𝑖(𝑡)

⋅ 𝑝 − 𝑄̇

_{𝑐𝑜𝑛𝑣}_𝑖

− 𝑄̇

_𝑟𝑎𝑑_𝑖

) 𝑡

_𝑖

𝑚

_{𝑑𝑖𝑠𝑐}

𝐶

_𝑝_{𝑑𝑖𝑠𝑐}

𝑄̇

_{𝑐𝑜𝑛𝑣}_𝑖

𝑄̇

_𝑟𝑎𝑑_𝑖

𝑄̇

_𝑟𝑎𝑑_𝑖

= 𝜖 ⋅ 𝜎 ⋅ 𝐴

_{𝑑𝑖𝑠𝑐}

⋅ 𝑇

_{𝑑𝑖𝑠𝑐}⁴

𝐴

_{𝑑𝑖𝑠𝑐}

𝜎 =

5.670 × 10⁻⁸ ^W

m² K

𝜖

𝑄̇

_{𝑐𝑜𝑛𝑣}

= ℎ̅ ⋅ 𝐴

_{𝑑𝑖𝑠𝑐}

⋅ (𝑇

_∞

− 𝑇

_{𝑑𝑖𝑠𝑐}

) 𝑇

_∞

𝑁𝑢 ̅̅̅̅ =

^ℎ^̅𝐿

𝑘_𝑎𝑖𝑟

2.1.4.3 Analytical estimation of the average heat transfer coefficient

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Cylindrical body

ℎ

_𝑐𝑦𝑙

̅̅̅̅̅ =

^{𝐶 𝑅𝑒}^𝐷

𝑚𝑃𝑟_𝑓¹³𝑘_{𝑎𝑖𝑟𝑓}

2 𝑟_{𝑑𝑖𝑠𝑐}

Planar body

ℎ

_{𝑝𝑙𝑎𝑡𝑒}

̅̅̅̅̅̅̅̅ =

^{0.664 𝑅𝑒}^𝐿

1/2 𝑃𝑟_𝑓^1/3 𝑘_{𝑎𝑖𝑟𝑓}

2 𝑟_{𝑑𝑖𝑠𝑐} 𝑃𝑟 ≥ 0.6

ℎ

_{𝑝𝑙𝑎𝑡𝑒}

̅̅̅̅̅̅̅̅ =

^{0.680 𝑅𝑒}^𝐿

1/2 𝑃𝑟_𝑓^1/3 𝑘_{𝑎𝑖𝑟𝑓} 2 𝑟𝑑𝑖𝑠𝑐

Rotating thin disc

ℎ

_𝑟𝑜𝑡

̅̅̅̅̅ =

^{√(0.036 𝑅𝑒}^𝑈^0.8⁾

2+(0.556 𝑅𝑒_𝜔^0.5)² 𝑘_{𝑎𝑖𝑟𝑓}

2 𝑟_{𝑑𝑖𝑠𝑐}

^𝑅𝑒^𝜔

𝑅𝑒_𝐿

> 0.18

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•

𝐴_{𝑒𝑑𝑔𝑒}= 2𝜋 𝑟_{𝑜𝑢𝑡𝑒𝑟}𝑡_{𝑑𝑖𝑠𝑐} 𝑡_{𝑑𝑖𝑠𝑐}

•

ℎ_{𝑒𝑞𝑢𝑖𝑣}

̅̅̅̅̅̅̅̅ = (ℎ̅̅̅̅̅ + 2 ℎ_𝑟𝑜𝑡 ̅̅̅̅̅̅̅̅)𝑅_{𝑝𝑙𝑎𝑡𝑒} _{𝑠𝑖𝑑𝑒}+ ℎ̅̅̅̅̅ 𝑅_𝑐𝑦𝑙 _{𝑒𝑑𝑔𝑒}

𝑅_{𝑠𝑖𝑑𝑒}= ^𝐴^{𝑠𝑖𝑑𝑒}

2 𝐴_{𝑠𝑖𝑑𝑒}+ 𝐴_{ℎ𝑜𝑙𝑒𝑠} + 𝐴_{𝑒𝑑𝑔𝑒} 𝑅_{𝑒𝑑𝑔𝑒}= ^𝐴^{𝑒𝑑𝑔𝑒}

2 𝐴_{𝑠𝑖𝑑𝑒}+ 𝐴_{ℎ𝑜𝑙𝑒𝑠} + 𝐴_{𝑒𝑑𝑔𝑒}

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𝑅𝑒_𝐿= 𝑅𝑒_𝑈= 𝑅𝑒_𝐷 𝑅𝑒_𝜔

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2.1.4.4 Simplified model: temperature response during continuous operation

𝑇_{𝑑𝑖𝑠𝑐(𝑛)}= 𝑇_∞+(1 − e^{(−𝑛 𝐵𝑖 𝐹𝑜)})Δ𝑇_{𝑑𝑖𝑠𝑐(𝑛−1)} 1 − e^{(− 𝐵𝑖 𝐹𝑜)}

Φ 𝑎_𝑥 𝑉_{𝑖𝑛𝑖𝑡𝑖𝑎𝑙} 𝑉_{𝑓𝑖𝑛𝑎𝑙}

𝐶_𝑥𝑆

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(88)

2.1.4.5 Calculation of disc temperatures using telemetry data from SC17

𝑝

_{𝑟𝑒𝑎𝑟}

= 𝑝

_{𝑓𝑟𝑜𝑛𝑡}

(

100−%𝐹𝑟𝑜𝑛𝑡𝑏𝑖𝑎𝑠

%𝐹𝑟𝑜𝑛𝑡𝑏𝑖𝑎𝑠

) (

^𝐴^MC1

𝐴_MC2

)

(89)

(90)

2.1.4.6 CFD analysis of the SC17 front brake rotor

(91)

2.1.4.7 Material selection and design exploration

(92)

(93)

(94)

(95)

Boundary conditions

0 20 40 60 80 100

0 2000 4000 6000 8000 10000 12000 14000

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Heat transfer coefficient [W/m2K]

Heat Flow [W]

Time [s]

Heat Flow [W] Heat transfer coefficient [W/m2K]

(96)

(97)

Mesh used for the design exploration study

Response surface

(98)

2.1.4.8 Detailed design of the rotors

(99)

µ𝑝𝑣 𝑝 𝑣

𝜔𝑟

(100)

(101)

Constraints

Applied loads

(102)

(103)

(104)

Meshing

-20 0 20 40 60 80 100 120

0 5000 10000 15000 20000 25000

41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

Heat Transfer Coefficient [W/m2K]

Heat Flux [W]

Time [s]

Heat Flux

Heat transfer coefficient - Calculated Heat transfer coefficient - Reference

(105)

2.1.4.9 Simulations results

(106)

(107)

(108)

(109)

(110)

(111)

(112)

2.1.4.10 Summary of the brake rotors design

(113)

0 0.2 0.4 0.6 0.8

1Mass

Iyy

Max.

Endurance Temp.

Max Auto X Temp.

Safety Factor at Max.

Braking cond.

Min. Life (Autocross Lap Loading Cycle)

Front Brake Rotors

SC17F SC18F V6

0 0.2 0.4 0.6 0.8

1Mass

Iyy

Max. Auto X Temp.

Safety Factor at Max.

Braking cond.

Min. Life (Autocross Lap Loading Cycle)

Rear Brake Rotors

SC17R SC18R V5

(114)

Considerations for the brake carriers

(115)

■ Wheel Spacer

■ Center pins

■ Wheel hub/Transmission planetary carrier

■ Wheel center nut

■ Brake rotor (friction ring)

■ Mounting bell

■ Wheel rim

(116)

Rear carrier

Front carrier

(117)

Floating buttons

𝐹_{𝑏𝑢𝑡𝑡𝑜𝑛}=^𝑇^{𝑏𝑟𝑎𝑘𝑒𝑟𝑒𝑎𝑟}

3 𝑟_{𝑏𝑢𝑡𝑡𝑜𝑛}

(118)

2.1.5 Manufacturing specification

(119)

(120)

■

(121)

(122)

2.2 Unsprung components of the suspension system

Wheels

(123)

2.2.1 Uprights

(124)

2.2.1.1 Constraints

(125)

2.2.1.2 Material and process selection

(126)

(127)

★★ ★★★★★ ★★★

★ ★★★ ★★★

★

★★★ ★★★★★ ★★ ★★★ ★★

★★★★ ★★★ ★★ ★★ ★

★★★★ ★★★★ ★ ★★ ★

★★★★ ★ ★ ★ ★★★

Yield strength [MPa] Tensile strength [MPa] Young Modulus [GPa]

7075-T651 516 573

71.7

7075-T6 488 567

(128)

2.2.1.3 Geometry definition

(129)

Upright

Wheel hub/Planet gears carrier Shaft seal

Wheel bearings Ring gear

Planet gear assembly Bearing preload ring Sun gear

Motor flange

Camber adjustment plates Magnetic oil cap

Flange O-ring

(130)

(131)

(132)

(133)

(134)

(135)

σ

(136)

2.2.2 Structural analyses

(137)

2.2.2.1 Single-component analysis: compliant boundary conditions based on bearing stiffness data

(138)

(139)

(140)

(141)

(142)

(143)

(144)

(145)

2.2.2.2 Suspension assembly analysis

0 0.2 0.4 0.6 0.8 1 1.2

Mass Material Efficiency

Max. Von Mises Stress at max Load

Max. Bearing seat deformation Front Upright SC18 vs SC17 -

Normalized Parameters

SC17 SC18 0

0.2 0.4 0.6 0.8 1 1.2

Mass Material Efficiency

Max. Von Mises Stress at max Load

Max. Bearing seat deformation Rear Upright SC18 vs SC17 -

Normalized Parameters

SC17 SC18

(146)

(147)

(148)

(149)

(150)

(151)

(152)

2.2.2.3 Manufacturing specification

(153)

(154)

CHAPTER 3. MANUFACTURING AND ASSEMBLY

3.1 Brake discs and mounting bells

(155)

(156)

(157)

(158)

3.2 Suspension arms and tie rods

(159)

(160)

3.3 Uprights

(161)

3.4 Integration on SC18

(162)

CHAPTER 4. TESTING AND VALIDATION

4.1 Track tests on the SC17 car

4.1.1 Tested components and instruments used

(163)

(164)

4.1.2 Location of the tests

(165)

4.1.3 Data collection procedure and tests performed

µ

(166)

(167)

(168)

4.1.4 Analysis of collected data

4.1.4.1 Brake load balance

(169)

4.1.4.2 Deceleration capability

(170)

4.1.4.3 Brake discs temperatures

(171)

µ

µ µ

µ

(172)

µ

(173)

(174)

4.2 FSAE Italy – 11

^th

to 16

^th

July 2018

(175)

4.3 Front brake calipers failure

(176)

(177)

4.4 Front brake discs failure

(178)

4.5 Test session of August 16

^th

, 2018

4.5.1 Instruments used

4.5.2 Location of the tests

(179)

4.5.3 Tests performed and data collection procedure

- - - -

4.5.4 Analysis of collected data

(180)

(181)

(182)

4.6 Brake rotors failure during Formula Student Spain 2018

(183)

µ

(184)

(185)

DISCUSSION

(186)

(187)

(188)

CONCLUSIONS

(189)

(190)

(191)

(192)

(193)

(194)

(195)

(196)