Inertial navigation is founded on Newton’s first law. An inertial navigation system means a navigation aid which utilizes a computer, motion sensors and rotation sensors to repeatedly calculate via dead reckoning the position, orientation, and velocity of a moving object without making use of external references.
Please note that it is not possible to provide a clear and universally agreed upon definition for the term “Inertial Navigation System (INS)”. It is build with two parts: inertial measurement unit and navigation computer. Inertial navigation unit will need to have two parts accelerometer – measure acceleration and gyroscope – measure rotation. Each sensor measure changes only in a single dimension. They should be barracked together, three for each unit. The navigation computer system computes the output data from measurements units and calculate the position.
Video: What is the Meaning of Inertial Navigation System
In the majority of of cases, Inertial navigation has a military application and it was initially designed to navigate rockets. Nowadays it is applicable with GPS receiver and it can be employed to increase accuracy of GPS systems – this technique is referred to as Kalman filtering.
Inertial navigation is commonly employed in an array of applications such as the navigation of aircraft, tactical and strategic missiles, spacecraft, submarines etc. The latest developments in the construction of MEMS devices have made it feasible to produce small and light inertial navigation systems.
Inertial navigation system errors: INS accuracy will drift with time. They suffer from integration drift: small errors in the measurement of acceleration and angular velocity are incorporated into progressively larger errors in velocity, which are compounded into still greater errors in position. INS position errors could be lowered by frequent updates of position from GPS and ground-based navigation devices.
Some other terms employed to talk about INS:
- Inertial Reference System (IRS)
- Inertial Navigation Unit (INU)
- Inertial Reference Unit (IRU)
- Inertial Measurement Unit (IMU)
- Inertial Guidance system