Inertial Navigation System
lastmod 2014-02-18created 2014-02-181 edits
An inertial navigation system (INS) is a navigation aid that uses a computer, motion sensors (accelerometers) and rotation sensors (gyroscopes) to continuously calculate via dead reckoning the position, orientation, and velocity (direction and speed of movement) of a moving object without the need for external references. It is used on vehicles such as ships, aircraft, submarines, guided missiles, and spacecraft. Other terms used to refer to inertial navigation systems or closely related devices include inertial guidance system, inertial reference platform, inertial instrument, inertial measurement unit (IMU) and many other variations.
An inertial navigation system (INS) is a device mounted on submarines, aircraft, missiles, etc. that senses its own position to guide it to its destination. Its operating principle is to obtain acceleration from a gyroscope and integrate it to get velocity, then integrate the velocity to get the distance traveled. Once the initial position is entered, it can always calculate and know its own position and velocity as it moves. It has the advantage of not being affected by bad weather or radio jamming, but errors accumulate and grow over long distances, so it is usually used with added correction from GPS, active radar guidance, etc.