Modification in Calibration of Strapdown Inertial Navigation System Due to Compensation of Inherent Error in Fixture Manufacturing

It is always easier to measure the deviation of a product from its design commitments, in comparison to making it identical to plan obligations. In this paper, this simple fact is utilized to compensate the inherent error of fixture fabrication by a mathematical modeling of possible sources of error, in calibration of strapdown inertial navigation system (INS). Since an INS should be mounted on the fixture, all deviations are completely transferred to INS. Compensating the inherent errors of a fixture surely guarantees a more accurate calibration, but its effectiveness depends on specific factors. Proposed method can upgrade a fixture with any manufacturing quality to accuracy level of measurement tool. This technique is explained by two examples. Data of industrial-grade strapdown INS is used to proof of claims.

Keywords:

Fixture , strapdown inertial navigation , INS calibration , Error compensation