The Satellite Review Magazine The Satellite Review Magazine Vol 1 | Page 36

Modeling Tomorrow’s
Material Handling
Solutions Today
By Ian McGregor,

Director, Emulate 3D, Ltd.

If You Think Things Are Changing Fast
Now, Just Wait for Tomorrow
The rise of the Internet and e-commerce
has created changes in buying behavior
that many material handling and
distribution companies are still
struggling to deal with. As consumers
get used to buying a wider range of
products online, they expect goods to
be delivered tomorrow at the latest, and
at no charge. For those responsible for
the design and running of distribution
centers and warehouses, keeping control
of the initial investment during the
design phase is key to profitability.
While designing material handling
systems capable of accommodating
change is difficult under these
circumstances, there are methods
that help to understand the system
behavior and reduce the risks associated
with automation projects of any size.
Simulation Leads to Better
Understanding
Dynamic simulation is an established
method which relies on creating a
model of the proposed system and
experimenting with it by introducing
loads in a realistic way. To be of use, the
model must be a reasonably accurate
representation of the real thing, and
its behavior under different operating
conditions must be close to that of the
actual system as it processes orders.
Industrial simulation models have
several main aims:
- To evaluate and experiment with
different system configurations in terms

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of equipment choices, system layout
choices, resource availability (fork lifts
and trained operators, for example), and
also in terms of system use (how to sort
and batch orders, when to introduce
replenishment stocks, etc.)
- To illustrate system operation and
response under various order loadings,
typically peak and normal, filling
or emptying the system, or both
simultaneously
Simulation models require considerable
data, and oblige those carrying out
the project to face issues and make
decisions earlier than they might
otherwise have done. This situation
leads to an enhanced level of system
understanding which produces very real
benefits, many of which are felt even
before the model is built.
Challenge Ideas in the Simulation
Sandbox
Once created, the model should be the
center of an initially divergent iterative
process which eventually refines the
chosen solution. Simulation results are
impartial, so new ideas can be tested
fairly against those coming from
experience, which might otherwise
carry more weight. The simulation
becomes a representation of the current
state of thinking about the project – it
can be seen, run, and challenged in
ways that are otherwise impossible
without such a transparent and
immediately understandable model.
Off-Line Emulation is Key to
Thoroughly Tested, Robust Control
Systems
A growing number of companies benefit
further from virtual analysis by
developing models for off-line controls
testing. The goal is to create and verify
the robust operation of the control
system, in parallel with the system build
and install. Prior to the existence of
dynamic emulation tools (as opposed
to IO switch-based testing, which is

limited to stepping through sequences
of events) controls testing could only
be carried out after the system was
assembled on site. Controls testing was
carried out under considerable time
pressure, and any project delays were
likely to create problems for the controls
engineers before the Factory Acceptance
Test (FAT) and system handover.
Off-line controls testing models are
again data-driven, but are connected to
real control systems running the actual
control programs. Loads or products
are introduced into the model in a
repeatable way and block photo eyes
and sensors just as their real counterparts do. These create inputs to PLCs
or higher level control systems which
then calculate outputs which start and
stop motors, trigger pushers, start robot
cycles, etc., just as they do in the real
world.
The advantages offered by off-line
controls testing are numerous:
- Controls testing can start before the
system is built
- Testing is controlled and repeatable
- Different parts of testing can be
carried out in parallel, on multiple PCs
- On-site time and cost is greatly
reduced
- On-site time is predictable, with little
variation
- Operators can be trained safely, with
no real system disruption
Reduce Your Investment Risk Through
Simulation and Emulation
As end users demand more flexible
systems to protect them from the
unforeseeable changes that are just
around the corner, analysis and controls
testing software becomes an ever more
essential part of the engineer’s toolbox.
The only