Inertiajärjestelmät

Inertiajärjestelmät, often translated as "Inertial Systems" or "Inertial Navigation Systems" (INS), are self-contained navigation and guidance systems that continuously determine a vehicle's position, orientation, and velocity without the need for external references. They achieve this by employing inertial sensors, primarily accelerometers and gyroscopes. Accelerometers measure linear acceleration, while gyroscopes measure angular velocity.

These sensors are typically arranged in a gimbals system or, more commonly in modern applications, a strapdown configuration. In a strapdown system, the sensors are rigidly attached to the vehicle, and their measurements are compensated for the vehicle's motion using sophisticated algorithms. By integrating the acceleration measurements over time, the system can calculate velocity and, by further integration, position. Similarly, integrating angular velocity measurements provides changes in orientation.

The core advantage of inertiajärjestelmät is their independence from external signals, such as GPS or radio navigation aids. This makes them highly reliable in environments where external signals may be unavailable, jammed, or unreliable, such as underwater, in space, or during electronic warfare. However, inertiajärjestelmät are susceptible to drift. Small errors in sensor measurements accumulate over time, leading to a gradual increase in position and velocity errors. This drift necessitates periodic recalibration or the integration with other navigation systems, like GPS, to maintain accuracy. Inertiajärjestelmät are crucial components in aerospace, marine navigation, and missile guidance.