Vehicle-to-Vehicle Communications Through Tires Caitlin Motsinger SURE Program Summer 2007 Research Advisor: Dr. Todd Hubing Graduate Student Assistant: Robert Clippard Clemson University ● Department of Electrical and Computer Engineering

Overview Background Information: Concepts and Applications of Vehicle Communications Case for Communication Systems in Tires My Summer Work: Research Paper in Vehicle Communications for Michelin Americas Research Corporation Small Scale Demonstration: Bike-to-Bike Communications Clemson University ● Department of Electrical and Computer Engineering

Vehicle-to-Vehicle Communications Clemson University ● Department of Electrical and Computer Engineering Basic Idea: Equip automotive vehicles with wireless communication systems, allowing them to exchange real time information Each vehicle is like a node in an ad-hoc wireless network System is mainly autonomous from the drivers’ perspective – they are only aware of it when a situation arises that needs their attention Expands drivers’ horizon, and makes them more conscious of their environment and relative position to each other

Vehicle-to-Infrastructure Communications Instead of communicating with each other, vehicles talk to base station nodes placed intermittently along the road Utilizes wireless systems from the car to the station, which then communicate wirelessly or through land lines to a data collection center Information can be collected from a large number of vehicles and processed by a third party Clemson University ● Department of Electrical and Computer Engineering

Applications of V2V and V2I: Safety The power of shared information makes drivers more aware of: State of the roadways Weather conditions Heavy fog Intersection violations Potential lane change violations Location of “vulnerable road users” such as pedestrians and cyclists Slow moving traffic around blind curves Flooding of I-96 in Livonia on July 12, 2007

Clemson University ● Department of Electrical and Computer Engineering Applications: Driving Efficiency Avoid congestion, saving time, fuel, and reducing pollution Choose the best time of departure Choose an alternate route to avoid accidents, flooding, etc. Predict travel time and make more reliable deliveries Updated information can be sent right to navigation units allowing drivers to easily:

Clemson University ● Department of Electrical and Computer Engineering Communication Transmission in the Tires The benefits of placing the transceivers in tires include: Yields four convenient, externally located mounting platforms Inflated tube can provide protection in the event of a crash Older cars could be updated with communication systems when tires are replaced The extra movement (rotational as well as forward) might help avoid bad transmission areas

Clemson University ● Department of Electrical and Computer Engineering The Michelin Paper: Concept The Michelin Americas Research and Development Corporation (MARC) has two main technical opportunities in V2V and V2I: To better understand these opportunities, MARC requested a research paper outlining: Chance to utilize “smart” tire sensors, such as those that can measure air pressure and tire-road cohesion Chance to push for placement of communication systems in tires A technical review of research initiatives in Europe, North America, and Asia A commentary on the business environment and how it might effect MARC’s place in the tire market

Clemson University ● Department of Electrical and Computer Engineering The Michelin Paper: Coverage A listing and short description of pertinent government research initiatives in Europe, North America, and Asia. Bandwidth allocation on all three continents for Wireless Access in the Vehicular Environment (WAVE). Standards development in North America in IEEE p (physical and MAC layers), and IEEE P1609 (upper layers). Business considerations focused on both vehicle communications and smart tire sensors. Recommendations to MARC on which initiatives yield the best business opportunities.

Building a Demonstration: The Concept User Interface Unit High-Powered Signals for Bike-to-Bike Comm. Low-Powered Comm. Between Tire Node and User Interface Tire Mounted Comm. Nodes Speed Sensor Clemson University ● Department of Electrical and Computer Engineering

Components on Tire THE TIRE NODE Sun SPOT by Sun Microsystems Laboratory Features: 2.4 GHz radio 3 axis accelerometer Plastic encasement 8 multicolored LEDs Programmed with Java THE SPEED SENSOR Magnetic Sensor and Target from Schwinn Bike Computer Features: Hall effect sensor Digital open/close switch

Clemson University ● Department of Electrical and Computer Engineering Demonstration End Result Two nodes mounted on separate bikes Each bike measures its own speed and distance traveled, and receives the current speed and distance of the other bike over its radio One of the nodes also relays all information wirelessly to a base station hooked to a computer Simple GUI allows user to view and save data

Clemson University ● Department of Electrical and Computer Engineering Data Collection Software

Clemson University ● Department of Electrical and Computer Engineering Transmission vs. Position RSSI at Different Distances Apart and Transceiver Orientations

Clemson University ● Department of Electrical and Computer Engineering Future of this Project: Object of Study Use bikes for in field testing Use 3 axis accelerometer to collect data Flood communication link to determine performance See how system is affected by the addition more transmitting nodes Create a user interface o Test bikes at different speeds and distances o Examine RSSI values while rotating vs. while stationary o Experiment to find the max range of the system o See if link quality is improved by tire mounting

Questions? Clemson University ● Department of Electrical and Computer Engineering

Acknowledgements Dr. Hubing, Advisor Robert Clippard, Graduate Student Assistant Dr. Haixin Ke, Post-Doc Dr. Wang, Communications Assistance Dr. Noneaker, SURE Program Director Josh Lawrence, SURE Graduate Assistant SURE Participants

Clemson University ● Department of Electrical and Computer Engineering Lastly… Go Irish!Go Tigers! BEAT USC!

Clemson University ● Department of Electrical and Computer Engineering Future of this Project: User Interface 4x20 Serial LCD by Parallax Features 80mm x 36mm; lb 5V supply voltage 2400, 9600, and 19,200 baud MICAz Wireless Mote by Crossbow Features 2.4 GHz communication radio 51 pin connector with analog input, digital I/O I2C, SPI and UART 58 x 32 x 7, 0.7 oz. (without batteries) Sample software for interfacing to LCD

Clemson University ● Department of Electrical and Computer Engineering Comparison of V2V and V2I Vehicle-to-VehicleVehicle-to-Infrastructure ProsConsProsCons 1) Lower cost for deployment 1) Requires a high market penetration 1) Provides better benefits even at lower deployment levels 1) Expensive system to build 2) Provides information with little lag time 2) Only can collect information from vehicles in range 2) Information collected from many vehicles in different areas 2) Must settle issue of who will pay for system upkeep 3) Works in rural areas 3) Information can be processed by a third party 3) Not practical in areas with low traffic volume

Sensing Changes in Speed Clemson University ● Department of Electrical and Computer Engineering Circuit is designed to be active low Code is written to be triggered by a transition from 5V to ground, which occurs when the switch first closes Internal timer keeps track of time between target hits, and uses this to calculate speed knowing sensor distance from the center of the wheel Total distance travel increments with each target hit 2 k Ω