Browsing by Author "Ali, Abdelrahman"
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- ItemOpen AccessLow-Cost MEMS-Based Pedestrian Navigation Technique for GPS-Denied Areas(2013-08-22) Ali, Abdelrahman; El-Sheimy, NaserThe progress in the micro electro mechanical system (MEMS) sensors technology in size, cost, weight, and power consumption allows for new research opportunities in the navigation field. Today, most of smartphones, tablets, and other handheld devices are fully packed with the required sensors for any navigation system such as GPS, gyroscope, accelerometer, magnetometer, and pressure sensors. For seamless navigation, the sensors’ signal quality and the sensors availability are major challenges. Heading estimation is a fundamental challenge in the GPS-denied environments; therefore, targeting accurate attitude estimation is considered significant contribution to the overall navigation error. For that end, this research targets an improved pedestrian navigation by developing sensors fusion technique to exploit the gyroscope, magnetometer, and accelerometer data for device attitude estimation in the different environments based on quaternion mechanization. Results indicate that the improvement in the traveled distance and the heading estimations is capable of reducing the overall position error to be less than 15 m in the harsh environments.
- ItemOpen AccessLow-Cost Sensors-Based Attitude Estimation for Pedestrian Navigation in GPS-Denied Environments(2013-09-16) Ali, Abdelrahman; El-Sheimy, Naser; Sesay, Abu-BakerPedestrian navigation has received significant attention in the last few years due to potential development in the smartphones’ technologies. Todays, most smartphones, tablets, and other handheld devices are fully packed with the required sensors that can provide navigation information such as Global Positioning System (GPS), triad gyroscope, triad accelerometer, triad magnetometer, and pressure sensors. The pedestrian dead-reckoning (PDR) technique requires traveled distance and direction in order to estimate the user position. Total distance can be determined using the step counting and step length estimation techniques using accelerometer data while, the relative attitude information can be estimated using gyroscope and accelerometer data. However, absolute heading information is required which can be provided using GPS or magnetometer. In GPS-denied environments, a magnetometer is used as the main source of heading update. However, the EMF is experienced to severe degradation in such environments which affects the overall performance of the magnetometer. Different techniques are proposed to overcome the deficiency due to the distortion in the sensed magnetic field to improve the overall performance of the magnetometer in the cluttered environments. For that end, this research is targeted towards improving the attitude estimation for pedestrian navigation in the harsh environments by developing sensor fusion technique to utilize the gyroscope rate in complementary with accelerometer and magnetometer data. Also, several contributions for step detection and step length estimation techniques are achieved to improve the overall performance and accuracy of the Pedestrian Dead Reckoning (PDR) algorithm.