Transcript Title of presentation goes here

Midway Design Review
Team 22:
Driver Assist
Electrical and Computer Engineering
Primary Solution
 Our solution is to create a
joystick that mechanically
controls the steering
wheel, brakes, and
throttle
 The joystick will pivot
horizontally allowing the
driver to turn left and
right.
http://img.gizmag.com/onehandeddriving.JPG?fit=max&h=670&w=77
0&s=4af0a21ce275fd7e9e9c78f8c92c344c
Electrical and Computer Engineering
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Block Diagram
Control signal
Joystick signal
Feedback signal
Power
Electrical and Computer Engineering
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MDR Deliverables
Have motor selected with correct output torque and
speed (have gearing ratio required computed)
Have a wheel jacket prototype created and
mounted on steering wheel base
Have control over motors movements
Have power circuit functioning to drive controller
Have a functioning brake and throttle prototype
Have a functioning battery recharger
Note: Red font was original MDR deliverable
Electrical and Computer Engineering
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Individual Assignments for MDR
Steve Cook:
Qingchuan Wu:
Throttle
Brakes
Power Supply
Motor Driver Design
Battery Charger
Sam Burke:
Gearing
Wheel Jacket
Controller Debugging
Electrical and Computer Engineering
Andrew Klinkowski:
Controller
Motor Driver
Implementation
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Motor Selection
Requirements
• Speed: 1.5rps
• Torque: 6Nm
Motor Specs
• Speed: 4000RPM
• Torque: .125Nm
• Brushless DC
Electrical and Computer Engineering
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Gearing
 A gearing ratio of 48 will allow us to have
the outputted torque required, while
staying within the speed limit.
 .125Nm * GearRatio = 6Nm
 GearRatio = 48
 Speed = (4000rpm/60)/48 = 1.38889 rps
Electrical and Computer Engineering
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Steering Wheel Jacket
 In our prototype design a piece of plexiglass
was used with a bike chain mounted to it
using JB Weld.
 The bike chain can be spun by the motor
which spins the steering wheel
Electrical and Computer Engineering
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Brake Prototype
 The brake stops the car and control reverse
in the video game.
• Includes: potentiometer, wire, and hand brake
• Potentiometer sends a voltage reference between 0.58V to
4.5V depending on depression of hand brake
• Higher voltage corresponds to harder braking
• 10k Potentiometer is used to reduce power and maximize
voltage reference swing.
Electrical and Computer Engineering
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Throttle Prototype
 Throttle allow the driver to control the gas
• Includes: potentiometer, wire, and throttle
• Potentiometer send a voltage reference between 3.92V to 0V
depending on position of the throttle
• Lower the reference voltage corresponds to faster
acceleration
• 10k Potentiometer is
used.
Electrical and Computer Engineering
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Power – Battery Charger Requirement
 Charge external 12V NiMH battery from the
cigarette port. 11- 14V input
 Limit Charging current below 3A
 Limit Charging voltage below 16V
Electrical and Computer Engineering
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Battery Charger
 Used to charge external battery pack from
12V car battery
Electrical and Computer Engineering
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Power – Battery Charger Result
 SEPIC
topology
charger
Electrical and Computer Engineering
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Power – Battery Charger Simulation
Electrical and Computer Engineering
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Power – Battery Charger Result
R load
Vin
I in
Vout
I out
P in
P out
Efficienc
y
20
12
1.56
15.35
0.748
18.72 11.4818
61.3
15
12
2.18
15.35
0.994
26.16 15.2579
58.3
10
12
3.04
15.35
1.46
36.48
22.411
61.4
9
12
3.39
15.35
1.62
40.68
24.867
61.1
8
12
3.4
15.35
1.77
40.8 27.1695
66.6
7
12
3.38
14.4
1.86
40.56
26.784
66.0
6
12
3.39
13.7
2.03
40.68
27.811
68.4
5
12
3.43
11.3
2.31
41.16
26.103
63.4
4
12
3.49
10.7
2.48
41.88
26.536
63.4
Electrical and Computer Engineering
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Power Supply
Electrical and Computer Engineering
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Power – Power Supply Requirement
 Requirement
• Provide regulated supply voltage 7.5V for controller
• Provide 2 isolated voltages 12V for driving Mosfet
 Implementations
• Flyback converter
• PI control on 7.5V output
• Mutual inductance regulation on 12V outputs
Electrical and Computer Engineering
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Power – Power Supply
 Requirement
• Provide regulated supply voltage 7.5V for controller
• Provide 2 isolated voltages 12V for driving Mosfet
 Implementations
• Flyback converter
• PI control on 7.5V output
• Mutual inductance regulation on 12V outputs
Electrical and Computer Engineering
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Power – Power Supply Simulation
Electrical and Computer Engineering
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Power – Power Supply Simulation
Electrical and Computer Engineering
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Power – Power Supply Result
 Able to provide
power to the
controller and
Mosfet Driver
 Insufficient cross
regulation due to
the leakage
inductance of the
toroid
Electrical and Computer Engineering
Vout
7.5
(V)
Iout
7.5
(A)
Vout
12
(V)
I out
12
(A)
7.86
0.5
10.9
0.15
7.44
0.3
12.6
0.10
7.40
0.1
15.8
0.05
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Motor Controller
 An arduino is used to control the motor.
 The arduino controls the frequency of the
motors phases
Electrical and Computer Engineering
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Motor Driver
 The driver amplifies the arduinos outputs to
be used by the motor
Electrical and Computer Engineering
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Motor Gate Driver
Electrical and Computer Engineering
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Basic Motor Phase control
U/V phase excitation
A’ = 0 B’= 1
A=0 B=1
Flow of current
Electrical and Computer Engineering
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Cost Analysis
Product
Cost
Brushless DC Motor
$127.00
Steering Wheel & Brakes
attachment
$57.00
Bike Chain
$6.00
Plexiglass
$4.00
JB Weld
$5.00
Hand Brake
$7.00
Throttle
$14.00
Total
$221.00
Electrical and Computer Engineering
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CDR Deliverables
Steve Cook:
Andrew Klinkowski:
3D print top half of the joystick
Install hand brake and throttle
Power supply PCB design
Full control over DC motor at
required spec of 1.5rps
3D printed wheel jacket
Mount bike chain to wheel
jacket
Sam Burke:
Implementation of gear train
Mount functional motor to drive
steering wheel
Controller PCB design
Qingchuan Wu:
PCB printed charger
Charger optimization increased
to 85%
Power supply rails well regulated
Electrical and Computer Engineering
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Motor Phase control- Buck (CDR)
U/V phase excitation
A’ = PWM B’= 1
A=0 B=1
Flow of current
Normal
PWM on
PWM off
Electrical and Computer Engineering
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Motor Phase control- Boost (CDR)
U/V phase excitation
A’ = 0 B’= 1
A = PWM B = 1
Flow of current
Normal
PWM on
PWM off
Electrical and Computer Engineering
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