Research Project Summary Information
GPS Dead-Reckoning System (ST11030-1)
GPS (Global Positioning System) receivers are commonly found in many modern vehicles. The two primary automotive markets for this technology are In-Vehicle Navigation (NAV) and Automatic Vehicle Location (AVL) systems. The transportation industry and the travelling public are becoming increasingly dependent on accurate GPS data to help them travel in an efficient manner. With fuel prices at historic highs, and given the competitiveness of fleet operations, the need for efficient transportation is now more important than ever.
Real-time GPS data allows real-time route planning and scheduling – maximizing the usefulness of the fleet’s vehicles. Intelligent route planning (e.g., limiting left-hand turns, avoiding signal lights, travelling on multi-lane highways, etc.) can save both time and fuel. AVL data can also be used to study driver behavior and can be used to increase operational efficiency by limiting excessive acceleration, lane changes, and other poor driving habits/decisions.
While GPS data is frequently accurate, it becomes inaccurate when the signals being received from the GPS satellites are obstructed / disturbed. These inaccuracies can lead to erroneous position determination, and subsequent erroneous plotting and analysis of vehicle position. It can prevent the in-depth analysis of position data used to ensure fuel and operational efficiency and operational safety. In addition, it can prevent appropriate vehicle rescheduling, wasting valuable time and fu
The system works by combining (“fusing”) GPS data with other sensors, combining the data in such a way that maximum vehicle position estimation accuracy is attained. The system will be constantly self-calibrating, eliminating the need for complicated installation / setup. It will be designed to be a “plug and play” device that can be easily integrated into existing AVL system designs. It will use standard NMEA GPS receiver messages as input, along with sensor inputs, and will output “corrected” NMEA messages. It will not only know when GPS signals are lost, it will also detect when GPS signals are erroneous, continuously correcting vehicle position and providing more accurate position estimation.
Current high fuel prices are placing economic pressure on vehicle fleets to become more and more efficient. Precise vehicle position is invaluable for efficient routing and just-in-time assignment of vehicles. Accurate position data can also be used to monitor how the driver is operating the vehicle (e.g., excessive acceleration/deceleration, excessive left-hand turns, etc.).
The project is complete and produced interesting results. The Contractor has demonstrated some of the advantages of using multisensory data fusion for increasing reliability and overall accuracy of vehicle position applications. It was shown that the antilock braking system (ABS) sensors provided on most modern day vehicles are a reliable and minimally invasive form of vehicle position sensing. Additionally, it was found that the GPS/ABS and magnetometer sensors provided the ideal combination of low noise and accurate sensing. Although the ABS sensors required the direct pulse measurements from an antilock brake system, ABS pulses require less integration steps to estimate planar vehicle position and orientation.
4455 Genesee St
Buffalo, NY 14225
NYSERDA Contact Information
R&D -Transport & Power Systems