Recommended Practice for Inertial Sensor Test Equipment, Instrumentation, Data Acquisition, and Analysis
|Publication Date:||9 June 2005|
Recommended practices for gyroscope and accelerometer testing are discussed, ranging from the equipment and instrumentation employed to the way that tests are carried out and data are acquired and analyzed.
Normative references are given in Clause 2, and a bibliography is given in Annex A. Test planning is described in Clause 3. General equipment and sensor-specific equipment for testing gyroscopes and accelerometers are described in Clause 4 and Clause 5. Mounting fixtures, test piers, accelerometer dividing heads, and gyroscope rate tables are discussed in Clause 6, Clause 7, Clause 8, and Clause 9. Three-axis tables for inertial sensor assembly (ISA) testing are described in 9.4.
Vibration and shock equipment, centrifuges, and environmental chambers are described in Clause 10, Clause 11, and Clause 12. Nuclear radiation facilities are discussed in Clause 13. Special readout instrumentation required in gyroscope and accelerometer testing is discussed in Clause 14, Clause 15, Clause 16, and Clause 17. Such instrumentation includes counter and frequency readouts, analog-to-digital (A/D) conversion readouts, temperature monitoring, and other monitoring and commanding functions over various types of interfaces and buses.
Computer data acquisition, control, filtering, and storage are described in Clause 18. The analysis of test data is discussed in Clause 19. Such analysis includes the plotting of data channels versus time and other data channels, least-squares fits of polynomials and other models to data, power spectral density (PSD) and Allan variance noise analysis, and regression analysis and parameter estimation.
Geophysics instrumentation is discussed in Clause 20 because inertial sensors are tested on the earth, which provides seismic, tilt, and other disturbances, but also provides the fundamental gravity and earth rotation inputs against which sensor parameters (such as scale factor) are calibrated. Therefore, the acceleration due to gravity at a test site and the site latitude and longitude must be accurately determined.
The calibration of test site coordinates and gravity acceleration, the calibration of test station electrical and other equipment, and fundamental time and frequency references are discussed in Clause 21.
This recommended practice is intended for people who test inertial sensors and analyze the results from such testing. The general and specialized test equipment employed in such testing is described, and recommendations are made on techniques for acquisition, filtering, storage, and analysis of the test data in keeping with modern practice.