Determining Accelerometer Zero Offset Errors during Bench Calibration
Static multi-position gravity inversion separates zero-g offset from scale factor while Allan variance bias instability defines maximum valid integration time.
Static Tumble Test
Rotational Mechanical Qualification
Inertial acceleration measurement quantifies the structural integrity of packaged electronic components when subjected to repeated impact forces during logistical transit. A static tumble test defines this process by subjecting a specimen to a controlled free fall sequence within a rotating drum. Internal paddles redirect the object to ensure random orientation and collision surfaces during every rotation.
This procedure isolates housing fatigue and interconnection stability under non-directional shock loading.
Calibration Boundary
Reference rotation speeds maintain specific impact energy levels throughout the evaluation sequence. Ambient room temperature provides the baseline thermal condition during these trials to prevent polymer embrittlement or adhesive softening from biasing the results. Laboratory equipment operators verify the tumble frequency using an optical tachometer to ensure the cycle duration aligns with the predetermined number of drops.
Consistent calibration of the drum drum diameter prevents variance in the potential energy release of the impacting object.
Material Response
Fatigue cycles alter the conductive paths within the device by inducing microscopic cracks in solder joints or surface mount contacts. Mechanical shock energy translates into kinetic stress at the lead frame interfaces during each contact event. Excessive energy absorption leads to intermittent signal loss long before visual damage appears on the outer shell.
Failure Criterion
Operational functionality verified after the conclusion of the tumble sequence determines the certification outcome. Post-test electrical characterization confirms that the resistance values remain within the tolerances set by the component manufacturer. Deviations outside these ranges constitute a failure of the mechanical design to withstand the intended transit environment.