Inertial+Navigation+Systems+-+Operation+&+Testing

Natalie

Note: This material is for reference purposes only

Operation Inertial Navigation System does not have frequency. Inertial Navigation System (INS) provides the pilot with precision navigation data referenced to Latitude and Longitude. Accelerometers and gyros calculated the linear degrees of freedom, velocity, measured the movement in the three rotational degrees of freedom to form the Inertial Navigation System. There are three linear degrees of freedom of x, y, z to specify position. There are three angular degrees of freedom of pitch, yaw, and roll to measure the attitude.


 * Pitch (Nose up and down), yaw (Nose left and right) and roll (Clockwise or counter-clockwise from the cockpit. ||


 * Math background of A six degree of freedom where x, y, z implies the linear of freedom and three rotary components. ||


 * [[image:leagueofextraordinarytechnicians/inertialplatform.gif]] ||
 * There are the gyros which would be mounted on the aircraft for the INS measurement in the three rotational and three linear degrees of freedom. ||

In 1967, M. Schuler had an idea about if the center of suspension is placed at res at the center of a circle, and the center of oscillation is placed in and restrained to its circumference, then the pendulum is normal to the locally vertical true. In applying this concept to the three-dimensional case of the earth, he did apply his idea with gyrocompass steaming error oscillations. Schuler’s idea and the concept of inertial navigation were the same with respect to the two artificial horizons involved. Inertial navigation systems are used in civil and military aviation, submarines and space technology in the past because it is so expensive to install one in the small aircraft. It is not necessary to put any location or information equipment, so it is a self-contained or autonomous system. The gyroscopes that mounted in the INS are so expensive and the parts would be affected by the friction so the drift happens. Once the alignment gets disturb, it has to be repeated. Inertial Reference Unit è Accelerometer è Ring Laser or Fibre Optic Gyro è Flight Management Computer è Using local vertical and direction of true north è Compass and sensors è Computer database è Inertial Measurement Unit Information è Gravity è Earth’s Rotation è Earth’s Geometry Pilot inputs è Present position of the aircraft è Horizontal alignment and heading based on assumptions Information for the pilot è Latitude è Longitude è True heading è Distance to waypoint è Ground speed è Wind speed è Wind direction Testing No Frequency for INS testing Parameters Testing è Position è Velocity è Attitude è Six-degree of freedoms è Atmospheric effects è RF interference è Flight dynamics è Bias instability Equipment è Inertial Reference Unit è Computer database è GPS è DME Step by step how to test INS è Using local vertical and sensing earth’s rotation allows aircraft to estimate latitude and computer direction of true north. è Present position is then entered and aircraft is ready to navigate è Because aircraft is referenced to true north, it can establish magnetic heading from a computer database. è Remote reading compass system is not required è With aid of FMC and navigation database IRU becomes INS
 * __Aircraft Equipments__**
 * __Ground Equipment__**
 * __Inputs__**
 * __Output__**

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