The basic motion elements Therblig

the 18 therbligs.

a basic motion element 1 of set of fundamental motions required worker perform manual operation or task. set consists of 18 elements, each describing standardized activity.

transport empty [unloaded] (te): receiving object empty hand. (now called reach )
grasp (g): grasping object active hand.
transport loaded (tl):moving object using hand motion.
hold (h): holding object.
release load (rl): releasing control of object.
preposition (pp): positioning and/or orienting object next operation , relative approximation location.
position (p): positioning and/or orienting object in defined location.
use (u): manipulating tool in intended way during course working.
assemble (a): joining 2 parts together.
disassemble (da): separating multiple components joined.
search (sh): attempting find object using eyes , hands.
select (st): choosing among several objects in group.
plan (pn): deciding on course of action.
inspect (i): determining quality or characteristics of object using eyes and/or other senses.
unavoidable delay (ud): waiting due factors beyond worker s control , included in work cycle.
avoidable delay (ad): waiting within worker s control causes idleness not included in regular work cycle.
rest (r): resting overcome fatigue, consisting of pause in motions of hands and/or body during work cycles or between them.
find (f): momentary mental reaction @ end of search cycle. seldom used.