Control oriented local area networks (COLANs) are being installed in
factories at an increasing rate. Traditionally, process control has
operated with a master scheduler (computer) monitoring a number of points
in a control grid. As the complexity of today's process control needs
grow, the need to process information locally increases. Microcontrollers,
networked with a master scheduler, can collect data from a locus of points
and make decisions as to whether the master needs to be notified or not.
By processing data locally, memory and execution time are freed up for the
master scheduler. Task implementation becomes modular in nature,
resulting in process control software that is easier to write, and
maintain.
This structure is the basis for COLAN V, a low cost, real-time,
distributed control network developed at Oregon State University. COLAN
V was used as the foundation for the creation of a multi-media
presentation system. Six microcontrollers were networked together to
remotely control the operation of projectors, projector screens, and
lighting. Based on the application the master scheduler was replaced by
a tape player. This allowed the storage of the audio part of the
presentation on one track of the tape and the storage of the synchronized
control signals on the other track. This distributed control network
supplied a low cost solution to a need that was not addressed by the
commercial market at any price. / Graduation date: 1992
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/37184 |
| Date | 19 August 1991 |
| Creators | Baily, Albert L. |
| Contributors | Herzog, James H. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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