Sensitivity of Tri-Axial Accelerometers within Mobile Consumer Electronic Devices: A Pilot Study

Tri-Axial accelerometers built into mobile devices allow for the measurement of motion characteristics by measuring the instantaneous acceleration of an object, compared to gravity at any given time. The objective of this study was to establish a protocol for a large scale study to determine the sensitivity of acceleration values. Five devices were used to collect instantaneous accelerations recorded by the SWAY Software in a steady state. Repeated measures were recorded in both screen-up and screen-down positions with the device laying flat and angled to 60-degrees. In the flat position, screen-up and screen-down mean accelerations were -1.0074g (+0.0202g) and 0.9966g (+0.0189g) respectively with a sensitivity of 0.0165g (+0.0086g). In the 60-degree position, screen-up and screen-down mean accelerations were -0.5094g (+0.0198g) and 0.4929g (+0.0207g) respectively with a sensitivity of 0.0190g (+0.0065g). These devices demonstrated consistent sensitivity values across multiple devices as demonstrated by low coefficients of variability.