Electrical and Computer Engineering Midway Design Review Team 22: Driver Assist

2 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. 0&s=4af0a21ce275fd7e9e9c78f8c92c344c

3 Electrical and Computer Engineering Block Diagram Control signal Joystick signal Feedback signal Power

4 Electrical and Computer Engineering 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

5 Electrical and Computer Engineering Individual Assignments for MDR Steve Cook:  Throttle  Brakes Sam Burke:  Gearing  Wheel Jacket  Controller Debugging Qingchuan Wu:  Power Supply  Motor Driver Design  Battery Charger Andrew Klinkowski:  Controller  Motor Driver Implementation

6 Electrical and Computer Engineering Motor Selection Requirements Speed: 1.5rps Torque: 6Nm Motor Specs Speed: 4000RPM Torque:.125Nm Brushless DC

7 Electrical and Computer Engineering 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 = rps

8 Electrical and Computer Engineering 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

9 Electrical and Computer Engineering 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.

10 Electrical and Computer Engineering 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.

11 Electrical and Computer Engineering Power – Battery Charger Requirement  Charge external 12V NiMH battery from the cigarette port V input  Limit Charging current below 3A  Limit Charging voltage below 16V

12 Electrical and Computer Engineering Battery Charger  Used to charge external battery pack from 12V car battery

13 Electrical and Computer Engineering Power – Battery Charger Result  SEPIC topology charger

14 Electrical and Computer Engineering Power – Battery Charger Simulation

15 Electrical and Computer Engineering Power – Battery Charger Result R loadVinI inVoutI outP inP out Efficienc y

16 Electrical and Computer Engineering Power Supply

17 Electrical and Computer Engineering 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

18 Electrical and Computer Engineering 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

19 Electrical and Computer Engineering Power – Power Supply Simulation

20 Electrical and Computer Engineering Power – Power Supply Simulation

21 Electrical and Computer Engineering 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 Vout 7.5 (V) Iout 7.5 (A) Vout 12 (V) I out 12 (A)

22 Electrical and Computer Engineering Motor Controller  An arduino is used to control the motor.  The arduino controls the frequency of the motors phases

23 Electrical and Computer Engineering Motor Driver  The driver amplifies the arduinos outputs to be used by the motor

24 Electrical and Computer Engineering Motor Gate Driver

25 Electrical and Computer Engineering Basic Motor Phase control U/V phase excitation A’ = 0 B’= 1 A = 0 B = 1 Flow of current

26 Electrical and Computer Engineering Cost Analysis ProductCost Brushless DC Motor$ 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

27 Electrical and Computer Engineering CDR Deliverables Steve Cook:  3D print top half of the joystick  Install hand brake and throttle  Power supply PCB design Sam Burke:  Implementation of gear train  Mount functional motor to drive steering wheel  Controller PCB design Andrew Klinkowski:  Full control over DC motor at required spec of 1.5rps  3D printed wheel jacket  Mount bike chain to wheel jacket Qingchuan Wu:  PCB printed charger  Charger optimization increased to 85%  Power supply rails well regulated

28 Electrical and Computer Engineering 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

29 Electrical and Computer Engineering 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