In deriving the cycle time equations, the I/O point was assumed to be located at the lower lefthand corner of the rack. Based on the particular type of hardware involved, however, the exact location of the I/O point may not coincide with the lower lefthand corner of the rack. In fact, suppose the I/O point is located 12 from the lower lefthand corner of the rack, as shown below:

Further assume that the storage rack is small—say, 150 long and 30 high. The S/R machine travels at 400 fpm and 80 fpm in the horizontal and vertical directions, respectively.
Calculate the expected S/R machine travel time for single- and dual-command cycles for the above case. Note: In traveling from the I/O point to a location in the rack (and vice versa), the S/R machine is not required to pass through the lower lefthand corner of the rack. Compare your results with the expected travel times obtained if the I/O point is assumed to be located at the lower lefthand corner of the rack; show the percent difference.

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P/D 12 + 150' 30'