OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
Figure 2 shows that type of handle is a significant parameter affecting the HR. High HR is observed in case of
lower handle position, the reason for this may be that while lifting from floor the worker has to bend more than
that of upper handle position so worker has to exert much force as compared to upper handle position. As J.M.
Deeb et al. (1985) have shown that Handle-position effects on forces exerted, heart rate and psychophysical
indices were large compared with the effect produced by a 25% change in container weight. C.G. Drury (1980)
stated that. The effect of handles was equivalent to a weight change of 1-2 kg for Heart Rate and Rated
Perceived Exertion, but much higher (2-14 kg) for Body Part Discomfort measures.
Table 5. Main effects of HR (Raw data)
LEVEL HANDLE BOX SIZE WORKER VERTICAL DISTANCE WEIGHT
HORIZONTAL
POSITION
L1 107.04 103.58 104.88 103.10 106.47 107.96
L2 109.92 110.37 113.50 108.61 107.91 108.69
L3 * 111.49 107.07 113.73 111.06 108.78
L2-L1 2.88 6.79 8.62 5.51 1.44 0.73
L3-L2 * 1.12 -6.43 5.11 3.14 0.09
DIFFERENCE 2.88 -5.67 -15.05 -0.40 1.70 -0.64
L1, L2 and L3 represent levels 1, 2 and 3 respectively of parameters., L2-L1 is the average main effect when the corresponding
parameter changes from level 1 to level 2. L3-L2 is the average main effect when the corresponding parameter changes from level 2 to
level 3.
Table 6. Main effects of HR (S/N Ratio)
LEVEL HANDLE BOX SIZE WORKER
VERTICAL
HORIZONTAL
WEIGHT
DISTANCE
POSITION
L1 -40.56 -40.29 -40.39 -40.25 -40.52 -40.63
L2 -40.82 -40.84 -41.08 -40.71 -40.64 -40.71
L3 * -40.93 -40.60 -41.11 -40.91 -40.73
L2-L1 -0.25 -0.55 -0.69 -0.46 -0.12 -0.08
L3-L2 * -0.09 0.49 -0.40 -0.27 -0.01
DIFFERENCE -0.25 0.46 1.18 0.05 -0.15 0.07
L1, L2 and L3 represent levels 1, 2 and 3 respectively of parameters. L2-L1 is the average main effect when the corresponding
parameter changes from level 1 to level 2. L3-L2 is the average main effect when the corresponding parameter changes from level 2
to level 3.
Table 7. Pooled ANNOVA (Raw data)
SOURCE SS DOF V F-RATIO SS’ P%
HANDLE 112.20 1.00 112.20 7.35* 96.95 2.71
BOX SIZE 659.06 2.00 329.53 21.60* 628.54 17.55
WORKER 722.29 2.00 361.14 23.67* 691.77 19.31
VERTICAL DISTANCE 1016.06 2.00 508.03 33.29* 985.54 27.51
WEIGHT 424.53 2.00 212.26 13.91* 394.01 11.00
HORIZONTAL POSITION 7.27 2.00 3.63 0.24 -- --
ERROR 640.89 42.00 15.26 -- 785.49 21.93
TOTAL 3582.30 53.00 -- -- 3582.30 100.00
*Significant at 95% confidence level, F Table (Handle position);4.07, F Table (Others);3.22; SS: Sum of squares; DOF: Degree of Freedom; ;
V: Variance; SS’: Pure Sum of Squares
Table 8. Pooled ANNOVA (S/N Ratio)
SOURCE SS DOF V F-RATIO SS’ P%
HANDLE 0.29 1.00 0.29 2.25 -- --
BOX SIZE 1.44 2.00 0.72 5.55* 1.18 17.43
WORKER 1.52 2.00 0.76 5.86* 1.26 18.63
VERTICAL DISTANCE 2.22 2.00 1.11 8.57* 1.96 29
WEIGHT 0.48 2.00 0.24 1.86 -- --
HORIZONTAL POSITION 0.03 2.00 0.02 0.13 -- --
ERROR 0.78 6.00 0.13 -- 2.36 34.91
TOTAL 6.77 17.00 -- -- 6.77 100
*Significant at 95% confidence level, F Table (Handle position);5.99, F Table (Others);5.14, SS: Sum of squares; DOF: Degree of Freedom; V:
Variance; SS’: Pure Sum of Squares
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