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IE 553 Engineering of Human Work Dr. Andris Freivalds Class #15. IE 553 Engineering of Human Work Dr. Andris Freivalds Class #15. RWL = 51(10/H)(1-.0075|V-30|) (.82+1.8/D)(1-.0032A)FMxCM. Frequency Multiplier. Ex. #1 - Infrequent Lifting.
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IE 553 Engineering of Human Work Dr. Andris Freivalds Class #15 IE 553
IE 553 Engineering of Human Work Dr. Andris Freivalds Class #15 IE 553
RWL = 51(10/H)(1-.0075|V-30|) (.82+1.8/D)(1-.0032A)FMxCM IE 553
Frequency Multiplier IE 553
Ex. #1 - Infrequent Lifting RWLor = 51(10/H)(1-.0075|V-30|)(.82+1.8/D)(1-.0032A)FMxCM Box into Car RWLdest = 51(10/H)(1-.0075|V-30|)(.82+1.8/D)(1-.0032A)FMxCM IE 553
Ex. #2 - Repetitive Lifting Sam restocks cases of Coke (compact, with handles): 1) 5/min for 8 hrs, each weighs 20 lbs. 2) from cart to shelves (worst case, V=0, to V=40) 3) twisting 45° each way, H=15 for shelf RWLor = 51(10/H)(1-.0075|V-30|)(.82+1.8/D)(1-.0032A)FMxCM RWLdest=51(10/H)(1-.0075|V-30|)(.82+1.8/D)(1-.0032A)FMxCM IE 553
Frequency Multiplier IE 553
Effect of Multipliers - 1 IE 553
Effect of Multipliers - 2 IE 553
Effect of Multipliers - 3 Frequency Multiplier IE 553
Multi-Task Lifting • Multi-task lifting ↑ LI over single-task • ↑ LI from worst case, as marginal effect • Calculate Composite LI (CLI) from: • Single task RWL (STRWL) • Frequency independent RWL (FIRWL), FM=1 • Single task LI (STLI) • Frequency independent LI (FILI) • CLI = STLI1 + FILI2x(1/FM1,2 – 1/FM1) IE 553
Ex. Multi-Task Lifting CLI = STLI1 + FILI2x(1/FM1,2 – 1/FM1) CLI = 1.6 + 1.0x(1/.88–1/.94) + 0.67x(1/.7–1/.88) = 1.9 IE 553
Frequency Multiplier IE 553