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Team Pishro-Nik and Ni Chris Comack - Simon Tang - Joseph Tochka - Madison Wang. Car-to-Car Communication for Accident Avoidance. March 5, 2009. Professor Pishro-Nik Advisor, Assistant Professor, ECE. Professor Ni Advisor, Assistant Professor, CEE. Background.
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Team Pishro-Nik and Ni Chris Comack - Simon Tang - Joseph Tochka - Madison Wang Car-to-Car Communicationfor Accident Avoidance March 5, 2009 Professor Pishro-Nik Advisor, Assistant Professor, ECE Professor Ni Advisor, Assistant Professor, CEE
Background Automobile accidents are both dangerous and costly Over 42,000 fatalities in the United States every year. More than 2.9 Million injuries from 6.4 Million car accidents annually. Combined cost of 230+ Billion dollars per year. Responsible for 5% of preventable deaths each year (JAMA). Goal: To provide a system to reduce these rates by warning drivers before a collision happens. How? Use GPS to track position and vehicle’s OBD-II port to monitor speed and acceleration of vehicles. Communicate this information among cars on the road via Dedicated Short Range Communication in the 5.9GHz spectrum. Source: Mokdad AH, Marks JS, et al. (March 2004). "Actual causes of death in the United States, 2000". JAMA291 (10): 1238–45.
Proposed Solution Use of Car to Car Communication • Cars 2 & 3 emit audio warning indicating Car 1 is decelerating rapidly. • The cars operators now have more time to respond to this dangerous situation, decreasing the risk of collision.
Design & Requirements System must be scalable Track car’s location with GPS receiver Use OBD-II (on-board diagnostic connection) to monitor speed, acceleration, and other information from car’s computer Standard on all cars made after 1996 – includes 150 million+ cars on the road in the U.S. today. Communicate between vehicles using DSRC (Dedicated Short Range Communication) Transceiver
GPS – Problem • No GPS Coordinate in Response Message
GPS – Progress Process Response Correctly if there are GPS Coordinates
GPS Statistics Measure Latitude/Longitude in One Location Refreshes Coordinates
Inputs & Outputs • Inputs: SPST Power Switch, two momentary push-buttons. • Outputs: Green LED indicator, red LED warning light, Piezoelectric element for audible warning.
Data Collection • GPS coordinates updated at rate of 1 Hz. • Time-stamp acquired from GPS at same rate. • Heading, or compass direction, calculated from comparing GPS location to previous coordinates. • Speed information from Engine Control Unit polled at approximately 10 Hz. • Acceleration calculated from current and previous velocity values. • Control signal to monitor transceiver buffer; above five data points received from other units at max. frequency possible.
Data Transmission • Total processing time is minimized by performing heading and acceleration calculations before transmitting. • Minimal packet size allows frequent transmission of single packet containing all pertinent information. • Data transmitted after each update to prevent stale data. “Dead reckoning” also implemented to fill in the blanks between each GPS update.
Transceiver updates Goals from last time Confirm Range (at least 150 m) Tested at 160 m Implement/confirm receiving functionality To do Integrate with GPS, OBD-II Receive/send from multiple sources
Ethernet Packet Structure Header 33 bytes SRC/DST MAC addresses SRC/DST IP addresses Length Other data and payload Transceiver info Channel/power to send, etc. Payload, padding, checksum Payload will include position, speed, timestamp, acceleration, and heading ~13 bytes
PCB Progress Currently only the layout for transceiver portion is done Things to come GPS interface (serial port) OBD-II interface layout Inputs & Outputs Ship out design for manufacturing