3.2 COMPUTER COMMUNICATION TO SUPPORT FMS
3.2.1 Basic Computer control functions
NC part program storage
Distribution of the part programs to the individual machine tools
- include post processing for specific machine formats
Production control
- decisions of part mix, rates, inputs to parts of system
- desired production rate for parts per day
- number of raw workparts available
- number of applicable pallets
- routes pallets to load/unload area
- gives instructions to operator about desired parts via a data entry unit (DEU)
Traffic Control
- Regulates materials transfer system to ensure parts are moved between desired workstations. This may be problematic, depending upon the transportation system used. Can act like a railway switch operator.
Shuttle Control
- moves parts between stations and main conveyor
- coordinates actions between machines, and primary handling system
Work handling system monitoring,
- monitor both work parts, and pallets.
Tool Control
- tracks tools at each station (and reroute parts if necessary, or notifies operator to install parts)
- tool life monitoring, and operator orders for replacement
System performance monitoring and Reporting
- Generate management reports
3.2.2 Data Files Required in a FMS system,
Part program file
- numerical control files for each part, and for each machine which may make a part
Routing File
- A list of machines which the parts must be routed through for completion, including alternates in some cases.
Part Production File
- Production parameters for each workpart
- allowances for in-process inventory
- used for production control
Pallet reference file
- a record of which parts a specific pallet is fixtured for
- each pallet is individually identified
Station Tool File
- a file for each workstation identifies,
- codes of cutting tools at station
- used for tool control purposes
Tool-life file
- keeps tool-life value for each tool in the system for comparison with maximum value.
3.2.3 System reports generated by an FMS system,
Utilization Reports
- summarize individual, and group efficiencies for stations.
Production Reports
- daily and weekly reports of parts produced in the FMS
Status Reports
- a snapshot of present conditions in the FMS system for,
Tool Reports
- list of tools at (or needed at) a workstation
- tool life status reports
A Graphical Depiction of a Workstation Controller
