Dylan Benedict (EE) - Team Leader Jace Fugate (EE) - Member Jamel Ahmed (EE) - Member Kyle Kissner (CSE) - Member Advisors: Dr. Khanna & Dr.Ledgard Presentation Outline I. Introduction 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 Introduction • • • • 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 Purpose • Provide older vehicles with technological improvements. • Cost efficient alternative to buying a newer vehicle. • 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 Module 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 Constraints • 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 IR2125 IRF510 Buck Converter Design Calculations: Switching Frequency TON TOFF 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 MAIN MODULE Subsystem Smart Car Plug In Gantt Chart Testing Issues & Solutions How It Works MAIN MODULE SUBSYSTEM 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 Issues 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 Solutions • 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 smartphone. • 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 Capabilities 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 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 Supplier Price OBD-II $51.90 Adafruit $98.39 Amazon $40.36 Amazon $8.99 Radioshack $14.98 Digikey $25.92 Adafruit $33.54 Total 274.08 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 Arduino • Store user’s vehicle data on a database for anytime access • Battery life display • Solar panel output current display Conclusion • 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 Questions?