Direction Cosine Computational Error

• Author(s): John W. Jordan,
• Publisher: National Aeronautics and Space Administration
• Pages: 103
• Language: en

Description:... Strapdown inertial systems possess a potential advantage over more conventional inertial systems since they do not require a mechanical gimbal structure to maintain a stable coordinate reference. Instead, strapdown systems replace the gimbal structure by a direction cosine matrix which is contained in and updated by the system computer. To assess the performance of a strapdown system or to determine the computer requirements, a detailed study of the computational error introduced by the computer is necessary. This report is concerned with the techniques which may be employed to estimate the computational error and its effects on system performance. Although focused upon a particular problem of practical importance, many of the techniques have a wider applicability to aerospace in general.