Analysing marker gaps during work-related activities of daily living using an optometric system

摘要

Six work-related, goal oriented activities of daily living (ADLs) were recorded for five men and five women with a six-camera VICON 512~(TM) optometric system. Three non-collinear markers were placed on each arm segment and the upper trunk to track movements, while minimising skin-movement artefact. Despite careful camera placement, 57% of recordings had trajectory gaps over 0.167 seconds long, although this was better than the 90% found when tracking one arm at a time with a three-camera system. Results show gap prevalence was highest during changing screwdriver bit and lowest during cutting steak (2.48 and 1.27 gaps / recording, respectively). Distal markers on the wrist and hand accounted for 96% of the recorded gaps. Large calibration movements prior to ADL recordings reduced gaps. Subject motions and anthropometry played roles.