An AS$/$RS is being designed; randomized storage is to be used. One alternative being

considered is to have each aisle be $70$ tall and $310$ long. The S$/$R has a horizontal

speed of $425$ fpm and a vertical speed of $80$ fpm$.$ It requires $0\mathrm{.}40$ minute to pick up or

deposit a load. The activity level for the system varies during each shift. The heaviest

operating period is a time during which a large number of retrievals must be per$-$

formed. During peak activity, each S$/$R must be capable of performing $30$ retrievals per

hour and $10$ storages per hour. It is expected that $100\%$ of the storages will be per$-$

formed with dual$-$command cycles.

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$10$ QUANTITATIVE FACILITIES PLANNING MODELS

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a$.$ Can the system handle the required workload? Why or why not?

b$.$ If$,$ during the peak period, the number of retrievals is $28$ per hour and the number

of storages is six per hour, what will be the utilization for each S$/$R$?$