Rack and roll automation strategies in material handling systems

BY ARC ADVISORY GROUP DECEMBER 2001

Rack and Roll Automation Strategies
in Material Handling Systems

Executive Overview ................................................................................ 3

Simulation Reduces the Risk in Material Handling Capital Expenditures .... 4

Automotive Plants Seek Common Controls.............................................. 6

Bottling Lines Seek Improvements in Line Efficiency.................................. 8

AC Drives Threaten to Invert the Automation Hierarchy.......................... 11

Material Tracking Is Essential................................................................ 12

Predictive Maintenance Remains Untapped in Material
Handling Solutions .............................................................................. 14

Enterprise & Automation Strategies for Industry Executives

ARC Strategies • December 2001

Shift toward equipment upgrade versus new plant capital spending

Capacity increases to deal with the new economy

Material handling logistics is strategic

Goods and information are moved concurrently in the supply channel

Mass customization

Zero inventory levels

Tighter collaboration between partners

Electronic commerce

Availability of intelligent material handling solutions

Strategic Trends Creating a Renewed Emphasis in Material Handling Solutions

WMS Solution

Conveyor
PLC
Zone Routing
Computer
PLC DataHwy +

RocketPort
422 Converter Support
Modem
Bar Code
Scanner

Up to 16 Bar Code Scanners
Typical Controls Configuration
Analog Line

Information and Automation Systems Demand Tighter Integration

2 • ARCweb.com • Copyright © ARC Advisory Group


Executive Overview

Material handling solutions are assuming a very strategic role in the im-
provement of order to delivery cycles, inventory reduction, and satisfying a
continuously changing buying culture. When thought of as a process, mate-
rial-handling solutions remains at the core of manufacturing, distribution,
consumption, and disposal activities. As the automotive, pharmaceutical,
and food & beverage industries continue to restructure and consolidate an
increasing demand for material handling solutions capable of preparing
shipments which contain multiple brands will keep the industry growing at a
rapid pace. Distribution centers are now shipping uniquely loaded pallets
containing a diversity of products based on individual store locations. This Guided Vehicles
is placing greater emphasis on the information management, extensibility,
Cartoners
and flexibility of the automation systems installed in the plants.
Conveyors

Material handling has become a priority as variety, availability, convenience, Carousels
and quality combined with a trend toward zero inventory levels is driving an Pick and Place
efficient movement of merchandise from manufacturer & distribution centers
Unloading Machines
to customers. Component suppliers and manufacturers are forming collabo-
Material Tracking
rate relationship as shipments of subassemblies are being delivered to the
discrete assembly lines in an ordered sequence and only as required on a Line Coordination
timely basis. This is placing enormous demands on the uptime of material Palletizers
handling equipment and accuracy of picking while continuously increasing Routing
the speed movement of material and delivery of services. Consequently, top
Robotics
to bottom automation solutions have become a strategic element in material
Sortation systems
handling systems for manufacturing plants, assembly plants and distribution
centers. Forklift trucks, conveyor systems, monorails, cranes, sortation sys- Accumulators
tems, palletizers, depalletizers, pick-to-light, Automatic Guided Vehicles, Diverters
Automatic Storage and Retrieval Systems, carousels, and robotics comprise Storage & Retrieval
many of the subsystems used to speed and automate the movement of goods.
Material Handling
Subsystems
The primary focus of this report is on emerging technologies in automation
and information systems necessary to converge on material handling systems
to achieve business goals of the organization. However, the importance of
Warehouse Management Software (WMS) cannot be overlooked for optimal
inventory management in discrete production and in distribution centers.
WMS remains an integral part of optimizing equation in manufacturing to-
day.

Copyright © ARC Advisory Group • ARCweb.com • 3


Simulation Reduces the Risk in Material
Handling Capital Expenditures

As industry after industry is continuing to downsize and “de-engineer”
automation continues to provide tremendous productivity gains. In some
plants the number of employees has dropped by as much as 50 percent. This
trend translates into a need for a higher, more sophisticated approach to
planning material handling systems. Today, Discrete Event Simulation
(DES) software is utilized to analyze and optimize a physical manufac-
Autosimulations
turing and material handling process. These packages contain powerful
CACI three dimensional modeling capabilities that simulate material flows
Lanner Group and process activity on a subsystem basis. Delmia, Tecnomatix, and
Enterprise Dynamics Rockwell Systems Modeling are some of the companies today that have
strong capabilities in physical modeling and work cell design.
Tecnomatix

ORCA Simulation Is Imperative
Frontstep It is inconceivable today to consider a material handling capital expendi-
ProModel ture for either a distribution center or a manufacturing facility without
simulating the entire system. Systems integrators, material handling
Rockwell Automation’s
Systems Modeling equipment suppliers, and in-house engineering staffs rely on manufac-
Micro Analysis & Design turing DES packages to evaluate new facility designs and analyze the
benefits of proposed upgrades to existing facilities. In many cases the
Wolverine
business requirements are changing so rapidly simulation and modeling
ALPHATECH
is no longer a single time event, but is viewed as a continual process
Mesquite over the lifetime of the facility. As businesses move toward zero levels
Imagine That of inventory there is a greater demand on distribution centers and
ThreadTec manufacturing plants to deliver goods with a faster turnaround time.
And as the business demands evolve, the topology of your material
Discrete Event Simulation
Suppliers handling equipment may need to be improved or reconfigured.

Desktop PCs Are Capable of Complex Simulation
The increased processing power of the desktop PC has had a dramatic effect
on the DES market. Previously, simulations of real problems required costly
workstations and lengthy runs made by simulation professionals with exper-
tise in both statistics and simulation languages. New technical developments
are simplifying the modeling process and enabling casual users to effectively
apply simulation technology specifically as many software suppliers move
toward object based technology to model subsystems in the plant. The range
of applications for simulation technology is therefore rapidly expanding and



vertically oriented packages that address specific industry needs and markets
are fast becoming available. While there are still technical differences among
simulation products, there is also a consensus that most simulation products
are capable of adequately addressing the normal range of modeling prob-
lems. Issues such as model size limitations, speed, and flexibility are
considered a thing of the past. Focus has now shifted to developing features
that enable a broader application of DES by casual users. Enhanced visuali-
zation tools, interoperability, hierarchical modeling, object-based
programming, optimization, and automatic scenario elaboration are key fea-
tures that distinguish individual offerings.

Simulation tools are spreading across the distributed enterprise
Simulation tools are spreading
to enable collaboration between business systems demands and
across the distributed enterprise to
manufacturing requirements. Tools for 3D design of factory
enable collaboration between
work cells are being combined with DES to encompass simula- business systems demands and
tion of the entire manufacturing layout. Flowcharting tools manufacturing requirements.
designed for business process reengineering are being extended
to include embedded discrete simulators enabling users to ob-
serve the system dynamics as they evaluate “as-is” and “to-be” designs.

Define Material Handling Requirements with Production Scheduling
Simulation is increasingly applied in the planning and scheduling sector for
finite-capacity scheduling of production. These rules based packages allow
scheduling of demand streams while utilizing the DES engine to evaluate
strategies. On-line production scheduling in conjunction with plant Collabo-
rative Production Management systems can be managed with these types of
systems. Production scheduling software typically focuses on scheduling
applications as well as those who provide complete APS solutions from sup-
ply chain planning through plant level daily production schedules.

Web-based simulation may also be considered one of the key requirements
for future DES packages. Simulation models will be distributed across the
Internet to enable multiple users access to dynamic analysis of an operation.
Collaborative model building across the Internet is also seen as a feature that
will combine object-based and web-based technologies. Programming lan-
guage will become a key concern for web-based simulation and users are
advised to ensure the languages such as Java to provide complete model mo-
bility. The dynamism that exists in the current DES marketplace bodes well
for end users seeking to minimize the risk in new projects.



Automotive Plants Seek Common Controls

Material handling is an integral component of many discrete manufacturing
production lines. Convergence in control systems is taking place between
CNC systems and the overhead gantry systems used to advance material
through the production process. This is prevalent in
automotive and heavy machinery applications where
the metal fabrication is performed in progressive
steps. As production in engine and transmission
plants moved toward increasingly agile manufactur-
ing configuration, the complexion of control systems
on the plant floor has changed dramatically.

The age of dedicated transfer lines is coming to clo-
sure as many automotive plants are being used to
supplement production of other plants. The massive
capital investments and enormous production run
requirements of the dedicated transfer lines has been
replaced by the introduction of general purpose and
multifunction machine tools at each station. How-
ever, this has brought a new era to how work in
Automotive Engine Production Lines Exemplify
Agility in Metal Working Applications process is moved from station to station.

Overhead robotic systems are now the mainstay of the transfer line. Carte-
sian coordinate overhead gantry systems are moving engine blocks, heads,
and transmission casing between each stage of the production process. Stan-
dard and custom configured machine tools from leading edge OEMs such as
Grobe, Hulle Hiller, and Unova are providing the metal cutting capabilities
at each of the stations. Although these agile production lines cannot compete
with the production speeds attainable with dedicated single station transfer
lines, the automotive manufactures are trading off speed for a wider range of
operation and rapid changeover.

Take for example the Ford plant in Lima, Ohio built in 1957. This plant is a
living museum for automotive production systems as it has a combination of
dedicated transfer lines and newer agile manufacturing systems. The dedi-
cated transfer lines can produce over 600 thousand engines per year whereas
the agile lines are limited to slightly greater than 60 thousand engines per
year. However, agile production lines can easily be reconfigured to produce
six cylinder, four cylinder or eight cylinder engines. Machining tolerances



and engine specifications can all be modified with a change in the CNC ap-
plication program. A tremendous amount of production variation can be
handled with a single production line.

Standardization in Control Systems
The rapid pace of technology is transforming factory floor control systems.
Off the shelf CNC systems are replacing the dedicated single station transfer
line controls. Custom designed robotic controls are now converging with the
CNC systems. As many plants seek a common control solution for the met-
alworking and the material handling systems, the CNC controls have
extended their reach. Conceptually, this is not tremendous
reach for CNC systems, as the basis of a metal working ap-
plication requires a precision motion control system, which
is very similar to a robotics system. However, trying to di-
rectly apply a standard CNC solution to a robotics
application can be fraught with unrealized expectations and
some difficult problems. Overhead gantry systems do not
require the inverse kinematics required of a general-purpose
robotic solution as the axes are all orthogonal, however,
leading CNC suppliers such as Siemens and Indramat have
augmented their core CNC systems with inverse arm solu-
tions, teach pendant capabilities, and gripper control as
extensions to the standard CNC. In this manner, commonal-
ity in the control hardware in addition to the look and feel of
Teach Pendants Are Standard in Robotics
the human interface is maintained within the manufacturing plant. in Contrast to CNC Solutions

Adoption of PC-based HMI in the machine tool market by all the leading
CNC suppliers, including FANUC, Siemens, and Mitsubishi, has been an
enabling technology providing the ability to cost effectively adapt the look
and feel. HMI software has become an increasingly important element of
material handling and machinery functionality as a result of the tremendous
utility of a graphical interface combined with the benefits of common soft-
ware architecture. The automotive industry has rapidly moved to PC-based
platforms and the Windows family of operating systems, CE and NT/2000,
for machine and cell control systems. These are rapidly becoming informa-
tion systems as bar code scanners, radio frequency tags, and infrared tags are
being used to track the progress of every item in a manufacturing and mate-
rial handling workflow. Overall, manufacturers adopting PC-based systems
are able to derive numerous cost reductions in training and support in con-
junction with the ease of integration of plant floor and information systems.



Bottling Lines Seek Improvements in
Line Efficiency

In the food and beverage industry, the bottling and canning lines are the key
to running efficient operations. A wider range in bottle and can sizes is con-
tinuously challenging manufacturing engineers. It is not uncommon
today to design a bottling line to handle a two-ounce bottle as well as
three-liter vessel, however current designs result in compromises in
efficiency. To optimally handle such a wide variation in container
sizes requires running a single line at different speeds while also tak-
ing into consideration the coordination at the end of the line conveyor
with a case packer or flow wrapping machine. In addition, numerous
environmental problems plague the food and beverage industry such
as changes in humidity and static electricity causing jams at a pres-
sure combiner, rinsers, and case packers. Although many lines run a
single product for several days, end users are expending significant
effort in the reduction of change over time to adjust for the variation
in shape and size of bottles. However, based on ARC’s market re-
search it is apparent that much less effort is being applied to improve
the synchronization of conveyor speeds or focus on predictive main-
Manufacturing Efficiencies Are
Focused on Bottling Systems tenance. As a result, additional plant machinery is required to
account for unbalanced lines and rerouting production around
equipment failures. Accumulators, diverters, and smart conveyors are
widely used at strategic locations in the material handling lines to synchro-
nize between conveyor lines or modular packaging machinery.

Variable AC Drives Are Underutilized
Although variable speed AC drives are applied in bottling conveyor lines,
the number of installations is extremely low. It is estimated that less than
thirty percent of the installed conveyor lines today utilize variable speed
drive technology rather than traditional single speed drives that require large
accumulation tables. Manufacturers retrofitting existing lines and additional
expenditures in capital equipment to increase the line capacity are not speci-
fying variable speed drives. Consequently, large accumulation tables are
required on bottling lines consuming valuable floor space as well as increas-
ing the maintenance and service costs of the plant. While variable speed AC
drive technology is proven to increase line capacity, reduce equipment
downtime, increase the operating range, and radically improve the energy
efficiency, many manufacturing operations continue to apply the notion of a



single maximum speed. Installing a material handling solution that simply
subscribes to the notion that running a line at maximum speed results in
suboptimal performance. However, synchronizing the speed of each piece of
equipment or equivalently balancing the load enables performance optimiza-
tion.

Manufacturers Need to Develop a Retrofit Program
Conveyor systems are the most widely used material handling subsystems in
any manufacturing plant or warehouse distribution center. As such these
systems are also the most prone to failure. Comprised of moving belts, gear-
boxes, chains, and motors, conveyor lines require a significant amount of
continuous maintenance. Conveyors are utilized extensively in manufactur-
ing operations to move bulk raw materials such as grains, plastics, ore,
pallets, packed cases or simply transporting loosely proc-
essed goods such as bottles, cookies, candies or crackers. Manufacturers that try to specify controls
In many applications, conveyors are simply a commodity, and mechanical features are severely
purchased on price rather than feature and function. penalized by OEMs for nonrecoverable
Manufacturers that try to specify controls and mechanical engineering costs and are unable to
features are severely penalized by OEMs for nonrecover- benefit from volume discount pricing of
standard components.
able engineering costs and are unable to benefit from
volume discount pricing of standard components.

E&J Gallo, one of the largest wine producers in the world, uses conveyor sys-
tems extensively in their distribution center as well as the manufacturing
bottling plants. Unable to purchase conveyor equipment to their specifica-
tions, the engineering staff is kept busy upgrading off the shelf conveyor
systems. Plant engineers are trained specifically to identify technology that
will lower the cost of maintenance. Control systems are being integrated
with the conveyors, chain drives are replaced with belts or direct drives and
lube free bearing are used wherever possible. Clearly, this a tremendous en-
gineering cost to E&J Gallo, however the return on this investment is easily
recouped by reducing standard maintenance, unscheduled maintenance, and
unscheduled downtime. Overall, the goal of this manufacturing operation is
to increase the reliability in conjunction with improving the predictability of
maintenance.



Gallo made a huge leap by decentralizing the conveyor’s PLCs control sys-
tems. Case conveyors and bottle conveyors were all decentralized over
Ethernet. Networking the conveyor system is an integral part of a predictive
maintenance system. The lifetime of a mechanical system is well understood,
consequently the ability to track the usage of an individual conveyor pro-
vides a lever in implementing scheduled maintenance before a system fails.
Overall, the importance of information tracking is providing tremendous
benefits preventing unscheduled maintenance and downtime.

Conveyors Demand Continuous Maintenance to Prevent Downtime

Business Reasons Prevent New Technology Adoption
Manufacturers are moving toward modularity in conveyor systems to im-
prove on the maintainability of these systems while also benefiting from the
ability to reconfigure the manufacturing process. Although, the automation
technology exists to make conveyor systems much more reliable than they
are today, system integrators and OEMs are reluctant to change their stan-
dard product or consider a custom solution. Significant time and effort goes
into selection of bottling or packaging line equipment. This area usually
represents the largest capital investment in a plant, requiring the greatest
amount of maintenance, and holds the largest amount of work-in-process
(WIP). More should and can be done to maximize utilization of these assets
and reduce the amount of WIP.

Obviously, there are many business reasons for this resistance. High cost of
engineering and design is one of the most significant ones. Companies that
compete in this sector are in a highly competitive business where price is



very important. Consequently, many technology improvements in automa-
tion systems are not readily available to the end users.

AC Drives Threaten to Invert the
Automation Hierarchy

Factory automation solutions are evolving toward control systems moving to
the device level. Increasingly, plant engineers and system integrators are
adopting this broader concept of distributed control while traditional
automation providers are offering a wider variety of product solutions
that are interoperable. However, AC drive suppliers are challenging
the traditional automation hierarchy by incorporating standard logic
control with inverters. AC drives are evolving toward total machine
controllers in contrast to their heritage as simply an actuator. AC
drive suppliers recognizing the potential of the excess computational
capacity available in digitally controlled drives are incorporating PLCs
in these systems. While, some automation suppliers are offering AC
drives that are directly mounted to the motor in lower horsepower
rated applications such as fans or pumps. Consequently these types of
solutions are less viable in a material handling system. The emergence
of the AC drive consisting of an integral PLC, device network and
OPC connectivity is enabling machine builders to lower the number of
components in a system.

Intelligent and Full Function AC Drives Alter Control Architecture
Traditional automation architectures place the AC drive simply as a control-
lable I/O point on a PLC. However, the integration of PLC directly into the
drive has simply inverted the automation architecture for many distributed
control applications. That is to say, the AC drive is now a viable element to
be considered for logic control and actuation. Specifically, in the case of con-
veyor systems, the continual pressure to lower the cost of wiring and reduce
the number of components lends well to an AC drive solution with logic con-
trol capability. Conveyors are becoming modular in nature as material
handling applications seek to use common control modules that can be re-
configured for a wide variety of applications.



Integration of PLC in an AC drive is not sufficient. Networking, persistence
in data, and standard communication interfaces are necessary to match the
demands of many applications. Although the extra processing power has
benefited applications by offering flexibility and additional options, such as
self-tuning, self-diagnostics, and optimizing techniques the important issue
today is ease of integration with other systems.

Connectivity Leads to Modularity
In a networked environment AC drives offer numerous advantages. There
are two sources of immediate benefits. Specifically, information becomes
more accessible throughout the entire plant and modularity of the machinery
is easier to implement. Networking expands the possibility of set
Baumuller point control, data collection, status monitoring, and even preventive
Emerson/Control Techniques
maintenance. Modular conveyor systems require synchronization as
well; therefore the availability of a networked interface provides the
Lenze
possibility of a plug and play system.
SEW
Suppliers of AC Drives As many conveyor manufacturers move toward ease of installation
with Integral PLC Control
and turnkey installation, the demand for common interfaces is grow-
ing. In many manufacturing domains OLE for Process Control (OPC) has
become very prevalent, while Ethernet is rapidly emerging on the factory
floor. OPC has become important for integration with the plant wide infor-
mation systems. Combined with an Ethernet solution and the ability to use
the same network for electronic line shafting of conveyors becomes an ex-
tremely viable solution. These two standards will clearly impact the AC drive
market as suppliers have rapidly integrated many networking options such
as Profibus, CANOpen, and DeviceNet.

Material Tracking Is Essential

Much of the value in a material handling system is focused on the Ware-
house Management Systems (WMS) software that is responsible for
improving the overall efficiency of moving finished goods, work in process,
and raw materials throughout the production plant. However, WMS sys-
tems cannot provide accurate retrieval and storage routing plans unless
products can be uniquely identified. Material tracking is where innovations
in the industry are taking place. The use of bar code, sorters, infrared, radio



frequency, and transmitting devices are enabling manufacturers to track
goods more accurately.

Individual product tracking is important from the perspective that it enables
the manufactured goods to carry process related information throughout the
entire production process. In addition, information systems are able to cata-
log unique product data providing companies the ability to reduce warranty
liabilities. Take for example the most recent case
between Firestone and Ford. If each and every tire
were tracked during the production process, the
number of warranty recalls would be limited to
only those tires produced on certain days or at
specific plants thereby significantly reducing the
number of recalls.

The greater amount of information tracked during
the production process enables manufacturers to
isolate lots of production if there is a shipment re-
call. Radio frequency and inductive tagging is
Material Tracking Solutions Are Increasing the Demands
very prevalent in automotive power train for Information Management on the Factory Floor
plants where virtually every facet of the pro-
duction process is maintained in a database. Bar coding is seldom used in
these types of environments as contamination from machining oils and metal
chips cannot be tolerated. Bar coding is extremely prevalent in electronic
assembly where clean room quality is maintained on the manufacturing
floor. Similarly, in the postal service every package and letter is labeled with
a bar code at the central sorting centers. In fact the postal service has pushed
the technology in Optical Character Recognition (OCR) systems to com-
pletely automate the placement of bar codes on each package. The postal
service has developed sophisticated algorithms for machinery that can take a
random assortment of letters, perform an OCR, and apply a bar code label at
a rate of 36 thousand letters per hour. However, this is absolutely necessary
to completely automate handling of millions of letters a day.

Tracking Increases Plant Floor Database Storage Needs
Regardless of the production environment, manufacturers are applying sen-
sor technology that can endure the environmental conditions of the plant.
There is simply a tremendous demand to keep track of the shipment location
by maintaining product specific information on the goods being manufac-
tured. Consequently, the content of information being tracked has escalated



over the last several years requiring more sophisticated sensor technology.
In addition to material tracking it is the maintenance records, machinery cy-
cles, and reliability of the machinery is all being maintained in a database.

As a result virtually all industries are incorporating
Industry
PC-based solutions as a substitute to the large
Standards Description
modular PLC based systems historically used to
SQL Server Database Access
manage the entire material handling system. This
OLE Object Linking and Embedding is not to say that the PLC does not have a place in
OPC OLE for Process Control material handling systems. As machinery becomes
ODBC Object Database Connectivity increasingly modular and material handling facili-
ties are required to be physically configurable, the
COM Component Object Model
PLC has become an embedded device in convey-
DCOM Distributed Component Object Model
ors, palletizers, cartoners, and sorters. This is a
Data Base Management in Material Handling radical change from the time when a large central-
Has Become an Absolute Necessity
ized PLC system would be responsible for
maintaining a database and controlling an entire
material handling system.

PC-based systems are functioning as the overall line overseers that handle
the data collection as well as reconfiguration of the line. It is only very small
lines that are utilizing a PLC as the line controllers today. PC-based solu-
tions inherently offer a much greater capability to manage large data
collection tasks demanded by wider adoption of material tracking. In effect,
new installations are standardizing on full PC-based controls on all of the
systems on the factory floor.

Predictive Maintenance Remains Untapped
in Material Handling Solutions

Plant Asset Management (PAM) is the integration of on-line, real-time condi-
tion monitoring and analysis combined with a predictive maintenance
strategy such as Reliability Centered Maintenance (RCM) and Enterprise As-
set Management systems. Typically, PAM systems are integrated with
higher-level systems in a manufacturing operation where maintenance
budgets have been reduced by as much as 30 percent after implementing a
PAM. To achieve this level cost reductions maintenance optimization initia-



tives used condition monitoring, analysis, and operations management are
necessary.

In contrast, material-handling applications installed in for inventory storage
and retrieval systems, distribution centers, and packaging lines do not have a
comprehensive PAM strategy. System integrators that are responsible for
design and installation of the many material-handling systems that are in-
stalled today do not have the power to push OEMs toward technologies that
would enable PAM. Manufacturers seeking performance improvements
need to consider maintenance and service of the automation systems in the
supply chain as well as the factory automation machinery used to produce
goods. Suppliers of material handling systems such as conveyors, palletiz-
ers, cranes, packers, and sorters need to use embedded control technology to
provide system integrators the tools needed to incorporate predictive main-
tenance, scheduled maintenance, and remote service. Manufacturers have an
untapped reservoir of improvements that can be achieved by focusing on the
machine utilization, downtime, and increasing machine life of their material
handling systems.

Make
Supply Distribute
Supply Chain Mgmt
Supply Chain Mgmt ERP Supply Chain Mgmt
Supply Chain Mgmt

ITRAM EAM/CMMS

PIMS PAM

Control System

Plant Measurements, Including PCM

Plant Asset Management (PAM) Are Prevalent
in Manufacturing



Dynamic Condition Monitoring Optimizes Manufacturing
Time based maintenance schedules for machinery are commonly applied to-
day, however this is not the most cost-efficient solution. Embedded software
in AC drives and precision motion control systems, which are at the heart of
material handling systems, have radically improved the ease of use, commis-
sioning, and diagnostics. The next generation of these systems will provide
advanced software capabilities that will extend machine life, reduce mainte-
nance cost, and predict failures. AC drives and servo amplifiers are widely
available with digital signal processors, RISC, or microprocessors, which
serve as the embedded controller. The first generation of these all-digital so-
lutions simply eliminated many analog components, such as potentiometers
and capacitors providing a stable system independent of temperature varia-
tions and component fatigue. In addition these solutions also offer the
benefit of digital loop closure providing the ability to incorporate more ad-
vanced algorithms such as PID, pole placement, sensorless vector control,
feed forward, and non linear compensation. Dynamic auto-tuning is one of
the software advancements emerging on the market
Condition Algorithms
today that has incorporated features that are capable
Motor Cogging Cogging torque compen-
of continuously identifying the mechanical and elec-
sation for smooth speed
trical characteristics of the overall system.
Changing Load Adaptive tuning for
changing load conditions
These types of software features offer tremendous
Start-Up Auto tuning and automatic benefits in improving the overall performance of the
miswiring detection during
start-up machinery. It is not only wear and tear of mechani-
Machine Impact Jerk limit control allowing
cal components that are the source of the problem.
higher speeds and Take into consideration material handling line that
accelerations
needs to handle a large range in the weights of pack-
Power Output Power management to ages on a conveyor. In most cases the OEM would
maximize torque/ speed
over larger envelope have to make compromises configuring the system to
guarantee that the controllers would remain stable
Advanced Machine Control Algorithms
throughout the entire operating range, however with
auto-tuning drives are able to detect load changes
and make adjustments in the control algorithms dynamically. Robots and
conveyors are the most highly visible problem areas, which can immediately
benefit from this software technology. Overall, software compensation tech-
niques such as auto-tuning offer a much greater advantage over more
simplistic static condition monitoring features which do not compensate for
dynamic changes in mechanical components over time such as wear and
varying load conditions.



Maintenance based on an as-required basis by anticipating potential failures
reduces the amount of unnecessary downtime. High-speed processors allow
integration of complex control algorithms that observe changes occurring on
machine components and predict potential failures. The number of applica-
tions for dynamic condition monitoring are unlimited, however even some of
the more obvious problems are not being implemented on a wide spread ba-
sis.

• Shaft coupling fatigue detected by a shift in resonance frequency can be
used notify operators of a potential failure.
• Increasing friction in mechanical gears and ball screws can be overcome
by applying additional torque. Machine shutdown is delayed while con-
currently the maintenance staff is alerted.
• Changes in backlash that might affect positioning accuracy can also be
dynamically compensated with an advanced control loop, by observing
torque demand changes in both directions.

Distributed Control Adds Computational Capacity
Distributed computational capacity and move to standard industrial net-
works available in PLCs, motion controllers, and drives is a significant
enabler. The incremental cost of computing power combined with net-
worked interfaces is more than offset by the value that dynamic condition
monitoring and remote network access brings to plants. More intelligent
control algorithms better serves customers through the recording of a ‘ma-
chine signature’ at the time of installation representing
data of various machine parameters. OEMs shipping
machines worldwide can monitor machine perform-
ance by comparing initial machine signatures with
current signature information to determine potential
problems. These facilities enable faster machine instal-
lation, and provide enhanced trouble shooting on a
global basis using web-enabled technologies in control-
lers.

Manufacturers prefer to buy open control systems with
a common architecture across all equipment. This is Monitor Machine Performance on the Web
in direct conflict with a supplier’s goal to lock users
into buying equipment. Therefore, in the world of open control systems,
suppliers must look for new ways to differentiate products. One of the ways



for suppliers to slow down the continuing price erosion and to gain addi-
tional market share is to focus improving ROA for end users.

System integrators and end users need to consider the Total Cost of Owner-
ship when designing new facilities as well as upgrading existing systems.
Advanced control algorithms reduce the cost of maintenance, increase per-
formance, and extend the intervals between replacements. Machinery
equipped with advanced control algorithms and network connectivity is
critical element in introducing a PAM strategy in your material handling sys-
tems.



Analyst: Sal Spada
Editor: Ed Bassett
Distribution: MAS-D & MAS-H Clients

Acronym Reference: For a complete list of industry acronyms, refer to our web
page at www.arcweb.com/arcweb/Community/terms/indterms.htm
AI Artificial Intelligence EAM Enterprise Asset Management
ANSI American National Standards Institute EC Electronic Commerce
APS Advanced Planning & Scheduling EPM Enterprise Production Management
B2B Business-to-Business ERP Enterprise Resource Planning
B2C Business-to-Consumer HMI Human Machine Interface
BPR Business Process Reengineering IT Information Technology
CAGR Compound Annual Growth Rate ITRAM IT & Remote Asset Management
CAN Controller Area Network MRP Materials Resource Planning
CEMS Continuous Emissions Monitoring ODBC Open Database Connectivity
System OLE Object Linking & Embedding
CMMS Computerized Maintenance OPC OLE for Process Control
Management System PAM Plant Asset Management
COM Component Object Model PID Proportional Integral Derivative
CNC Computer Numeric Control PIMS Process Information Management
CPG Consumer Packaged Goods System
CRM Customer Relationship Management PLC Programmable Logic Controller
DCOM Distributed Component Object ROI Return on Investment
Model SPC Statistical Process Control
DES Discrete Event Simulation TMS Transportation Management System
EAI Enterprise Application Integration WMS Warehouse Management System

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