MAIN MODULE Subsystem Download

Dylan Benedict (EE) - Team Leader
Jace Fugate (EE) - Member
Jamel Ahmed (EE) - Member
Kyle Kissner (CSE) - Member
Advisors: Dr. Khanna & Dr.Ledgard
Presentation Outline
II. Problem Statement
III. Requirements
IV. Design
V. Smart Car Plug In
A. Gantt Chart
B. Testing
C. Issues & Solutions
D. How It Works
VI. Budget
VII. Conclusion
The Smart Car Plug In is a project that proposes a cost efficient design
to improve the technology within older vehicles.
The average cost of a new car or truck today is approximately $33,560.
The Smart Car Plug In is an alternative electronic system to purchasing
a new vehicle.
It consist of two user friendly components, the Main Module and the
Subsystem Module.
Problem Statement
Provide older vehicles with technological
Cost efficient alternative to buying a newer
Delivers live vehicle feedback to users.
Increase driver safety with added features
(i.e. backup proximity sensor)
The average age of automobiles on the road
is approximately 12 years old
Project Goals
To meet established electrical and
software engineering requirements
Have an impact on the consumer
Stay on schedule according to our
Gantt Chart
Utilize our supplied budget efficiently
Functionality Objective
Establish connection between the user’s
smartphone and their vehicle via bluetooth
Poll live vehicle data (i.e. RPMs)
Use transceivers to send backup proximity
sensor data from the Subsystem to the Main
Engineering Requirements
Electrical Engineering Requirements
The Main Module must receive power.
The Subsystem’s arduino must power up to generate the duty cycle to
control the buck converter.
The rechargeable battery's 12 volts need to be bucked down to 7.5 volts.
Must control when the Subsystem is drawing power to conserve energy.
The rechargeable battery must be efficiently recharged from a renewable
power source.
Software Engineering Requirements
ECU is accessed through the OBD-II port
Set the master (Main Module) and the slave (Subsystem)
Communicate via phone application
Phone communicates with The Main Module by bluetooth
Subsystem sets duty cycle on buck converter
Project Design
The major constraint for our project was budget. We were unable to
construct a product that matched our initial design due to high product
cost, tax, and shipping.
Time and manpower became an issue, so we were forced to utilize a third
party smartphone application instead of creating our own.
Electrical Specifications
• Correctly wiring the microprocessor to specified components.
• Powering system using 12V obtained through the OBD-II port.
• Connect the proximity sensor to the Arduino Uno.
• Pulldown resistor (10 kΩ) to ground to eliminate floating pins.
• Transceiver communication (3.3V).
• Bluetooth components (5V).
Wiring Schematic: Main Module
Wiring Schematic: Main Module
Wiring Schematic: Subsystem Module
Buck Converter
Converts 12VDC from the battery to 7VDC
Provides power to the Subsystem’s Arduino Uno
Designed using discrete parts on a prototype breadboard
A gate driver ramps a 5 volt arduino signal to 12 volts to switch the MOSFET
Arduino Signal
Output Voltage
Buck Converter Design
Buck Converter Design
Parts List:
• 1: Arduino Uno
• 1: 12 V Rechargeable Battery
• 1: IRF510 N-Channel MOSFET
• 1: IR2125 Single Channel Driver
• 1: 10 Ω Resistor
• 5: 0.1 µF Capacitors
• 1: 48 µH Inductor
• 2: 1N5818 Schottky Diode
• 1: Push Button
• 1: Toggle Switch
Buck Converter Design
Switching Frequency
Software Specifications
Programming for three Arduino Unos
a. Bluetooth Low Energy (BLE) - Arduino to smartphone communication
b. Transceivers (radio) - Module to module communication
c. OBD-II Adapter - Vehicle to Arduino communication
d. Buck Converter - Set output frequency and duty cycle
e. Proximity Sensor - Object distance calculation
f. Buzzer - Backup alarm trigger
Software Specifications: UML
Software Specifications: UML
Software Specifications: UML
Mechanical Design Elements
• Effectively contain all project components with affecting functionality
• Properly mount the toggle switches, push button, and solar panel
Smart Car Plug In
Gantt Chart
Issues & Solutions
How It Works
Gantt Chart
• The Smart Car Plug In team was able to stay on schedule and complete the project
in a timely manner by following our Gantt Chart
Unit Testing
Compiled sample programs
Connected smartphone to BLE module (Bluetooth Low Energy)
Setup transceiver communication
Sounded a buzzer based on proximity sensor feedback
Interfaced car with Arduino through OBD-II port
Added toggle switches to select data
Output a PWM frequency of 62.5 kHz
Bucked 12VDC down to approximately 7VDC
Integration Testing
Tested Bluetooth connection to third party iOS applications
Accessed Arduino’s SPI bus with both OBD adapter and BLE module
Confirmed live data from vehicle
Simultaneously polled multiple data types
Utilized the backup sensor
1. The nRF8001 BLE modules are unable to communicate to each other
2. SPI bus cannot handle OBD-II adapter, BLE module, and Transceiver
3. Arduino Micro unable to reach desired PWM output frequency (62.5 kHz)
4. Floating I/O pins
We utilized two transceivers in order to allow the Main and Subsystem modules
communicate. One BLE module was used to send polled data to the user’s
The Main module holds two Arduino Unos in order to avoid overloading the SPI bus.
One Arduino contains the OBD adapter and the BLE module
One Arduino has the transceiver.
The Arduino Micro was swapped out with an Arduino Uno, so we could reach a 62.5
kHz output.
Pull down resistors were added to I/O pins in order to eliminate floating pins
How To Setup
• Plug Main module into vehicle’s OBD-II port
• Attach Subsystem module on the rear of automobile
• Power ON subsystem device
• Turn smartphone’s bluetooth ON
• Utilize nRF UART application to connect smartphone to device via bluetooth
How It Works
• User selects what data to display on smartphone
• When toggle switch is selected on Main module, live vehicle feedback begins
polling on nRF UART iOS application
• If user selects backup proximity sensor toggle switch, the Subsystem sends live data
to Main module. If an object is detected at the rear of the vehicle, a buzzer sounds
Engine RPM (rpm)
Calculated engine load (%)
Engine coolant temperature (°C)
Absolute Engine load (%)
Ignition timing advance (°)
Engine oil temperature (°C)
Engine torque percentage (%)
Engine reference torque (Nm)
Intake temperature (°C)
Throttle position (%)
Intake manifold absolute pressure (kPa)
MAF flow pressure (grams/s)
Barometric pressure (kPa)
Vehicle speed (km/h)
Engine running time (second)
Vehicle running distance (km)
Ambient temperature (°C)
Vehicle control module voltage (V)
Hybrid battery pack remaining life (%)
Backup Proximity Sensor
Budget & Cost
We spent a total of $274.08
Our group was given a budget of $200, which
puts us only $74.08 over budget
Issues during initial design and testing led to
higher spending than expected
Components: Main Module
Parts List:
• 2: Arduino Unos
• 1: OBD-II Adapter
• 1: nRF8001 BLE Module
• 1: nRF24l01 Transceiver
• 1: Buzzer
• 4: 10 Ω Resistors
• 4: Toggle Switches
Components: Subsystem
Parts List:
• 1: Arduino Uno
• 1: nRF24l01 Transceiver
• 1: Proximity Sensor
• 1: 12VDC Battery
• 1: Solar Panel
• 1: Buck Converter
• 2: 10 Ω Resistor
• 1: Push Button
• 1: Toggle Switch
Future Potential
• Create an official app, which meets our product specifications and requirements
• Remove physical toggle switches and use smartphone application to select data
• Simplify product internal communication by removing transceivers
• Decrease physical size of product by printing circuits onto PCB
• Investigate constructing a custom microcontroller in order to decrease profit loss to
• Store user’s vehicle data on a database for anytime access
• Battery life display
• Solar panel output current display
• The Smart Car Plug In was successfully completed with multiple features, which
encompass both electrical and computer science engineering design.
Special Thank You
• Dr. Khanna and Dr. Ledgard for advising our project
• Michael Hontz for special assistance
• Dr. Niamat for course guidance