@article{Jeong_Park_2011,
	author = {Jeong, Tae-Gweon and Park, Sok-Chu},
	title = {An Algorithmic Study on Positioning and Directional System by Free Gyros},
	journal = {TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation},
	volume = {5},
	number = {3},
	pages = {297-302},
	year = {2011},
	url = {./Article_An_Algorithmic_Study_on_Positioning_Jeong,19,297.html},
	abstract = {The authors aim to establish the theory necessary for developing free gyro positioning system and focus on measuring the nadir angle by using the motion rate of a free gyro. The azimuth of a gyro vector from the North can be given by using the property of the free gyro. The motion rate of the spin axis in the gy-ro frame is transformed into the platform frame and again into the NED (north-east-down) navigation frame. The nadir angle of a gyro vector is obtained by using the North components of the motion rate of the spin axis in the NED frame. The component has to be transformed into the horizontal component of the gyro by using the azimuth of the gyro vector and then has to be integrated over the sampling interval. Meanwhile the authors suggest north-finding principle by the angular velocity of the earth?s rotation. That is, ship's heading is obtained by using the fore-and-aft and athwartship components of the motion rate of the spin axis in the NED frame.},
	issn = {2083-6473},
	publisher = {Gdynia Maritime University, Faculty of Navigation},
	keywords = {Positioning System, Algorithmic Study, Free Gyro Positioning System, Directional System, Free Gyroscopic Compass, Compass, Ship's Heading, NED (North-East-Down) Navigation}
}