Home About Research Publications People What's New Links Contact Us   UW   Radio Frequency Identification Light Detection and Ranging Forest Visualization Navigation Decision Support research updates   Navigation   Navigation Research - Details on inertial navigation trials   Combined Global Positioning System and Inertial Navigation System Can combining these technologies increase the accuracy of navigation under tree canopy? Limitations of GPS Current accuracy with a clear sky is 5-7 meters. Differential correction increases the accuracy to centimeters. Satellite signals can be reflected or blocked by: Trees Canyons Steep Slopes Water It is difficult to correct for these reflected signals. Reflections decrease the accuracy of data. Inertial Systems Inertial systems measure accelerations created by movement. Position information is calculated using these accerlerations and a known starting point. Can “drift” over time creating error Combination Accuracy There are indications that the combination of GPS/INU can increase the accuracy to 2 meters. We are planning field trials to analyze this   The Precision Forestry Home Page is provided by the College of Forest Resources. © 2000 - University of Washington, Precision Forestry Cooperative, including all photographs and images unless otherwise noted.