Created by:Kiumars Jalali

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Preliminary Suspension Design and Stability
Control Strategies for an Electric Vehicle with
Four In-Wheel Motors

• Created by Kiumars Jalali

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Vehicle Specifications
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Vehicle Dynamics
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Tractive Effort Characteristics
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Power Characteristics
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In-Wheel Motor Characteristics
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Vehicle Acceleration Performance
Driving on a dry road m 0.9
Driving on a wet road m 0.3
Driving on an icy road m 0.05
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Braking Performance
Ideal Braking Force Distribution vs. Fixed
Distribution
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Braking Performance
Importance of the Braking Ratio
CG height 0.4 m
CG height 0.4 m
CG height 0.4 m
65 Front 35 Rear
75 Front 25 Rear
80 Front 20 Rear
Braking time 3.2 s Braking distance 44 m
Braking time 3.5 s Braking distance 48 m
Braking time 3.8 s Braking distance 52.5 m
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Lateral Dynamics
Steady-State Skidpad Cornering
Bicycle Model
Front rear tire lateral Stiffness Ca
45210 N/rad
CG position a 0.82
m, b 0.98 m
Vehicle moment of inertia
Iz 950 kg.m2
Vehicle curb mass driver MT
100075 kg
Understeer behavior vchar
105 km/h
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Lateral Dynamics
Transient Skidpad Cornering
Vehicle Characteristics Subjected to Yaw natural
Frequency and Damping Rate
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Vertical Dynamics
Comfortable Ride
Safety Vehicle Handling
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Optimization Results
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Suspension Design
Front Double Wishbone Suspension
Rear Multi-Link Suspension
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Suspension Characteristics
Caster angle Caster trail
Kingpin inclination Kingpin offset
Design Data Front
Camber angle -0.5 deg Toe angle 0.1 deg Caster
angle 7.5 deg Caster trail 18.4 mm Kingpin
inclination 15.5 deg Kingpin offset -21.7 mm
Design Data Rear
Camber angle -0.5 deg Toe angle 0.1 deg Caster
angle 0 deg Caster trail 0 mm Kingpin
inclination 15.5 deg Kingpin offset -21.7 mm
Front Roll Axis hR,f 89.4 mm
Rear Roll Axis hR,f 94.7 mm
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Suspension Characteristics
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Steering Characteristics
55 Ackerman Behaviour
Roll Understeer Behaviour
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Driving Dynamics Behaviour
ISO Double Lane Change (ISO 3888)
Vehicle position Without Yaw Controller
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Yaw Rate Controller
Yaw Rate Controller Block Diagram
Bode Diagram of the Closed Loop Yaw Rate Control
System
Vehicle Position without Yaw Controller
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Traction Controller
Direct Drive PM DC In-Wheel Motor Model
Adhesion Coefficient vs. Longitudinal Slip
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Traction Controller
Decision Making Algorithm of the Traction
Controller
Traction control loop for a single wheel
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Traction Controller
Actual Slip During a Slip Controlled Acceleration
on a µ-split Road
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Traction Controller
Target Slip Decision During a Slip Controlled
Acceleration on a µ-split Road
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Traction Controller
Direct Drive PM DC In-Wheel Motor Torque
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Traction Controller
PM DC In-Wheel Motor Voltage
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Traction Controller