Rectification Displacement
Accelerometer performance depends upon the output shift induced by mechanical energy. Vibration rectification bias represents this unintended shift in the direct current signal of a sensor when subjected to high frequency oscillatory motion. Sensitivity errors emerge because the internal seismic mass responds nonlinearly to alternating inputs.
Proper calibration requires measuring the magnitude of this effect at multiple frequency intervals to verify stability.
Displacement Mechanism
An asymmetric structure inside the sensing element prevents perfect return to the null position during an oscillation cycle. Forces move the mass through a path where mechanical stops or non-uniform spring constants introduce a preferred offset direction. Constant acceleration fields combined with rapid movement intensify the error through internal mechanical clamping or friction variations.
Design engineers minimize this movement by stiffening the suspension and reducing the clearance within the housing.
Calibration Metric
Technical specifications state the allowable limit for this drift under standardized test conditions defined by the manufacturer. Each device displays a distinct value when subjected to a reference sinusoidal input that exceeds a specified threshold. Accuracy hinges upon isolating this shift from electronic noise or thermal gradients during the testing procedure.
Laboratory protocols demand the removal of all steady state acceleration from the test bench to ensure the rectification constant remains independent of gravity.
Error Consequence
Downstream instrumentation treats the bias as a legitimate input change. Systems integrating the data over time multiply the error magnitude by the duration of the movement. Precision control loops become unstable when an uncorrected offset enters the feedback chain.
Large rectification errors compromise the integrity of inertial navigation because the device incorrectly records movement.
