1. Networks ben cook 11/12/2012

2. OVERVIEW
Dr. Red talked about network topologies, network access, communication mediums (cables, fiber-optics, wireless), and OSI standards
CURRENT STATE:
Local area networks (LAN) connect
devices that are relatively close to each
other, usually with ethernet.
Improvements in fiber optic
technology has allowed LANs to
increase in physical size from a few
hundred feet to miles.

3. CURRENT STATE RS – 232: Universal Serial Bus (USB):
Standard for sending serial binary single-ended data and control signals. Defines voltage levels, signal timing, meaning of signals, and the physical size of connectors
Limitations with RS – 232 led to several other RS standards such as RS -422 (differential signaling), RS – 423 (unbalanced signaling), RS – 485 (can be used as a bus in multidrop configurations)
Slow speeds (max 1.5 Mbps), large voltage swings, and large physical connection lead to USB
Universal Serial Bus (USB):
Largely replaced RS – 232 connections, USB 3.0 able to reach speeds of 5 Gbps
Similar to Firewire, but USB is designed for simplicity and low cost while Firewire is designed for high speed/high performance
Firewire (IEEE 1394):
Serial bus interface standard that uses isochronous real time data transfer
Developed by Apple
Wired Ethernet (IEEE 802.3):
Uses coaxial, twisted, and most recently fiber optic cable that can reach speeds up to 100Gbps
Uses OSI standard to standardize data transfer

4. SUPPORTING TECHNOLOGY
WHERE, WHO, WHEN USED:
Pretty much everyone uses some form of networking to communicate with their manufacturing devices
COSTS:
SUPPORTING TECHNOLOGY
Networks are the supporting technology for everything else we’ve learned about in class
Appropriate software needed to control automated systems

5. References http://www.lammertbies.nl/comm/info/RS-232_specs.html
J. R. Pimentel. Communication Networks for Manufacturing. Prentice-Hall. 1990

6. USE IN INDUSTRY APPLICATION LIMITATIONS: VENDORS:
The goal of any network is to have all the components be able to communicate, so older equipment might not be up to current standards.
Current various standards might produce incompatible equipment
Lengths of traditional cable limited by weakening signal and interference
VENDORS:
Cimetrix – factory robot control
CODE (Cimetrix Open Development
Environment) machine modeling and
control software
JBT – AVG control
Control software to manage their AVGs
(only good for JBT products)
Inductive Automation
CISCO Systems Inc – customized and fully
supported solutions for general networking

7. EXISTING AND EVOLVING STANDARDS:
Open System Interconnection (OSI) model
From International Organization for Standardization
Way to characterize functions of a communication system in terms of layers
IEEE 802 a standard for networks that carry variable size packets, maps to Data link and Network layers

8. EXISTING AND EVOLVING STANDARDS
Generic Model for Communications and Control of Manufacturing Equipment (GEM)
Defines messages, state of machines, and scenarios to enable factory software to control and monitor manufacturing equipment. GEM compliant equipment share consistent interface and behavior
Developed by Semiconductor Equipment and Materials International (SEMI) organization

9. APPLICATIONS TECHNICAL PAPER LINK VIDEOS:
Ethernet-based Real Time Control Networks for Manufacturing Automation Systems, Kweon and Shin, University of Michigan
VIDEOS:

10. SUMMARY
Networks and control software are needed for automated equipment communication
Ethernet LANs are the most common
Several different standards (OSI, IEEE, GEM) ensure compatiblilty