Rockwell Automation FactoryTalk Scheduler Users Guide - Manual (Page 45)

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5
Scheduling Concepts
FactoryTalk Scheduler incorporates both an algorithmic and a simulation-based scheduler.
This chapter describes finite-capacity scheduling in general, details the differences
between these scheduling methods, and discusses how to select scheduling rules to
accomplish your objectives.
Finite-capacity scheduling
Finite-capacity scheduling (FCS) is the process of creating a production schedule for a set
of jobs that is to be produced using a limited set of resources. Each job is comprised of
one or more operations (machine, form, paint, etc.) that must be performed in a specified
sequence using the set of available resources (work-centers, machines, workers, etc.). A
schedule assigns a starting and ending time to each operation and sequences the
operations across the resources so that no resource conflicts occur. The operations are also
assigned in a way that any sequencing constraints are respected.
FCS can be done using a manual planning board (sometimes called a Gantt chart) in
which the available resources are listed down the left side. The operations are assigned to
the resource rows and spaced horizontally within each row to represent the passage of
time. Each operation is represented by a horizontal bar where the length of the bar
represents the duration of the operation.
S CHEDULING EXAMPLE 1
The figure below shows a simple planning board with one of many possible operation
schedules for three different jobs, denoted as Jobs A, B, and C. These jobs are produced
using two resources denoted as Resources 1 and 2. The label within each horizontal bar
denotes the job sequence (e.g., A-10 denotes Job A, Sequence Number 10). The data
defining the operations for each job are shown in the accompanying table.
Resource 2
Time
B-10 A-20 C-20
5 10 15
Resource 1 B-20 A-10 C-10