Transient Thermal Calibration in Quartz Resonant Accelerometers
Transient thermal calibration compensates quartz resonant accelerometer bias shifts caused by temperature gradients using differential thermal rate models.
IEEE Standard 1293
Specification Scope
Formal metrology standards define testing protocols, specification terminology and performance metrics for linear accelerometers. Published under IEEE Standard 1293, the standard establishes uniform procedures for determining dynamic parameters, bias repeatability, scale factor linearity and environmental sensitivities in inertial instruments. The document standardizes the reporting format so procurement specifications map directly to factory acceptance measurements.
Metrological definitions separate systemic instrument traits from installation errors and data acquisition noise. Sensor procurement relies on these test structures to verify compliance with mission criteria.
Testing Methodology
Laboratory evaluation requires precision dividing heads, centrifuge systems and linear rate tables to generate reference inputs. Under IEEE Standard 1293, accelerometer testing prescribes multipoint tumbling routines to separate static bias from scale factor asymmetry and cross-axis alignment errors. Rate tables sweep frequency bands to quantify dynamic frequency response and phase lag characteristics.
Temperature cycling during tumbling sequences records thermal coefficients for both bias and scale factor under static equilibrium. Dynamic vibration profiles quantify rectification errors induced by mechanical rectification and package resonances.
Verification Metric
Metrological verification demands explicit calculation of non-linearity, hysteretic drift and vibration rectification coefficients across all axes. The formal procedures within IEEE Standard 1293 specify least-squares regression techniques to extract model parameters from multipoint measurement sets. Allan variance calculations characterize stochastic noise components, separating white noise from flicker noise and random walk.
Test documentation records unmodeled residuals to bound the total sensor uncertainty budget.
Compliance Limit
Sensor screening protocols apply the standard up to the calibrated range limits of physical test hardware. IEEE Standard 1293 ceases to govern once sensor operation departs from the linear range or enters environments that exceed specified qualification profiles. Shock events above mechanical survivability limits require separate qualification methodologies outside standard accelerometer characterization guidelines.