Publication Date
2013
Document Type
Thesis
Committee Members
Marian Kazimierczuk (Committee Member), Kuldip Rattan (Advisor), Xiaodong Zhang (Committee Member)
Degree Name
Master of Science in Engineering (MSEgr)
Abstract
The effective deployment of Automated Guided Vehicles (AGV) in indoor hostile environment demands high precision localization for navigation purposes. The cricket system, based on Time Difference of Arrival (TDoA) approach, provides precise localization. It calculates TDoA between radio and ultrasonic signal to estimate distance between two cricket motes. The position, in the referenced coordinate system, is estimated by multilateration using estimated distances from multiple motes. Therefore, the position accuracy depends on the distance estimation which in turn depends on the TDoA calculation. Ultrasonic transducer, a component of cricket mote hardware, has highly directive radiation pattern which affects ultrasonic signal detection. This delayed detection of ultrasonic signal, based on distance and relative angle, introduces error in the distance estimation between a pair of two cricket motes. A low cost, easy to implement error correction method is developed in this thesis to remove error introduced by delayed ultrasonic signal detection. Relationship between error (in distance estimation), relative angle and distance between two cricket motes is derived using traditional regression analysis. This relationship is then used to predict and correct error involved in the distance estimation. Experimental results show that the mean error in cricket position estimation for 2-Dimension and 3-Dimension is reduced by an average 43% and 39%, respectively.
Page Count
67
Department or Program
Department of Electrical Engineering
Year Degree Awarded
2013
Copyright
Copyright 2013, some rights reserved. My ETD may be copied and distributed only for non-commercial purposes and may be modified only if the modified version is distributed with these same permissions. All use must give me credit as the original author.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.
