In production management field, the methods of motion analysis include therbligs
, MTM (methods-time measurement) , MOST (Maynard operation sequence technique) , and MODAPTS (The modular arrangement of predetermined time standards).
The well-established micro-motion studies' methodology, originated in twentieth century, emphasizes on: (1) a top-down segmentation of a primary task into basic motion elements ('Therbligs'); (2) recording of elements and key subtask performance in process-charts; and (3) obtaining metrics of performance for skill evaluation.
Apart from considering representative manipulation exercises from da Vinci surgical (SKILLS) simulator, real surgical videos were also analyzed with a list of predefined 'Therbligs' in order to validate the clinical relevance of this method.
Task analysis has its roots in the work of Gilbreth and Gilbreth (1921), who recorded elementary operations called therbligs
. A related development from this early work is the representation of tasks in network models for purposes such as estimating the completion time of the task and determining the allocation of resources (e.g., Elmaghraby, 1977; Modor & Phillips, 1970; Pritsker, 1979; Wiest & Levy, 1977).
These units were known collectively as "therbligs
"--Gilbreth spelled backwards, with the `th' transposed.