Validation of custom wearable sensors to measure angle kinematics: A technical report
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The objective of this study was to determine the accuracy of custom designed wearable sensors when compared to a robotic device to measure i) peak angles in a single plane (flexion/extension) and ii) the extent of error associated with speed of movement. Two experimental procedures were undertaken; i) one wearable sensor was mounted on the arm of a step motor that simulated wrist flexion/extension at the speed of 90°/s with the other wearable sensor static (flat surface); and ii) two wearable sensors were each mounted on a step motor which was programmed to move at two movement speeds 30°/s and 90°/s. When compared to pre-determined angles of the robotic device, the wearable sensors detected peak angles with mean error ranging from -0.95° to 0.11° when one wearable sensor was static and the other dynamic. When two wearable sensors were moving, movement at the higher speed (90°/s) had a mean error range of -2.63° to 0.54, and movement at the slower speed (30°/s) had a mean error range of -0.92° to 2.90°. The custom wearable sensors demonstrated the ability to measure peak angles comparable to the robotic device and demonstrated acceptable to reasonable error when tested at two movement speeds. The results warrant future in vivo testing.
KeywordsWearable sensors Inertial movement units Measurement Angle
Three-Dimensional Motion Analysis
- RMS error
Root mean square error
Degree of freedom
This research was completed with support from the Australian Government Research Training Program Scholarship and Perth Children’s Hospital Foundation. A grant was awarded from the Australian Catholic University to fund the development of the wearable sensors.
Compliance with ethical standards
Disclosure of potential conflicts of interest
Author CE holds a position at Perth Children’s Hospital, and CI is employed by the Australian Catholic University. The authors declare that neither the Australian Catholic University nor the Perth Children’s Hospital Foundation had a role in the conduct of the research or the reporting or interpretation of results.
Ethical approval was not required.
This study did not include human participants and therefore informed consent is not applicable.
Conflict of interest
The authors declare that they have no conflict of interest.
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