022.05 Inertial Navigation and Reference Systems (INS and IRS) Flashcards
In an inertial navigation system, the integration process amounts to making a time (multiplication/division) and enables to get (position from accelerations/accelerations from position).
In an inertial navigation system, the integration process amounts to making a time (multiplication) and enables to get (position from accelerations).
The drift of the azimuth gyro on an inertial unit induces an error in the poisition. ‘T’ being the elapsed time, the total error is proportional to (T/T÷2/T2).
The drift of the azimuth gyro on an inertial unit induces an error in the poisition. ‘T’ being the elapsed time, the total error is proportional to (T).
An INS uses measurement of acceleration sensed by the (north/east) gyro (horizontal/vertical) accelerometer to carry out allignment.
An INS uses measurement of acceleration sensed by the (east) gyro (horizontal) accelerometer to carry out allignment.
Average position error of the Inertial Navigation System is (0.5/1.0/1.5/3.0) NM or (less/more).
Average position error of the Inertial Navigation System is (1.5) NM or (more).
- 0.5 - 2.0 NM per hour -
Allignment time at mid-latitudes for an INS using gymbal gyros is approximately (5/10/20/30) min.
Allignment time at mid-latitudes for an INS using gymbal gyros is approximately (20) min.
Integrations: to know the speed it is necessary to:
Integrations: to know the speed it is necessary to:
- Integrate once the acceleration in time
Integrations: to know the INSTANTANEOUS speed it is necessary to:
Integrations: to know the INSTANTANEOUS speed it is necessary to:
- Integrate once the acceleration in time
- Know initial speed only
Integrations: to know the distance it is necessary to:
Integrations: to know the distance it is necessary to:
- Integrate twice the acceleration in time
Or
- Integrate once the speed in time
Integrations: to know the INSTANTANEOUS position it is necessary to:
Integrations: to know the INSTANTANEOUS position it is necessary to:
- Integrate twice the acceleration in time OR once the speed in time
- Know the initial position
- Know the initial speed
An IRS is a (strap-down/stabilised platform) inertial system. The (…) rate gyros and (…) accelerometers.
An IRS is a (strap-down) inertial system. The (3) rate gyros and (3) accelerometers.
An INS is a (strap-down/stabilised platform) inertial system. The (…) rate gyros and (…) accelerometers are mounted on (the same/two different) platform(s).
An INS is a (stabilised platform) inertial system. The (3) rate gyros and (2) accelerometers are mounted on (the same) platform.
The principle of the Schuler pendulum is used in the design of a (strap-down/stabilised platform) intertial system.
The principle of the Schuler pendulum is used in the design of a (stabilised platform) intertial system.
Should an INS platform be displaced from the horizontal, it would oscillate with a period of about (4/8/84) (sec/min).
Should an INS platform be displaced from the horizontal, it would oscillate with a period of about (84) (min).
- Shuler Period -
During the initial alignment of an INS, the equipment (will/will not) accept a 10° error in initial latitude but/and (will/will not) accept a 10° error in initial longitude.
During the initial alignment of an INS, the equipment (will not) accept a 10° error in initial latitude but (will) accept a 10° error in initial longitude.
Gyro-compassing of an INS (is/is not) possible in flight because it (can/cannot) differentiate between movement induced and misalignment induced accelerations.
Gyro-compassing of an INS (is not) possible in flight because it (cannot) differentiate between movement induced and misalignment induced accelerations.
