Tools for Rapid Simulation Modeling for the Paper Switching Application

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Tools for Rapid Simulation Modeling for the
Paper Switching Application

• Presented for RASIG
• by
• John Carson
• AutoSimulations

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A Modest Proposal

• AutoMod can do it!

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Who is this guy?What is AutoMod?

• AutoSimulations
• founded in 1982
• 108 employees worldwide
• offices in USA, UK, Japan, Taiwan, Singapore
• distributors in UK, Europe, Far East, Brazil
• headquarters in Bountiful, Utah
• owned by Brooks Automation (almost)
• ASI offers simulation and scheduling software,
  training and consulting
• main simulation product AutoMod

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AutoMod

• General purpose simulation package
• strong modern simulation language
• runs on Windows
• Templates to facilitate vehicle and material
  handling applications
• vehicles, conveyors, ASRS, bridge crane,
• tanks pipes for liquid and bulk
• vehicle templates can be applied to
• rail, trucks, ships
• Currently on version 9.0

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AutoMod Applications

• Bread n butter
• Manufacturing
• Warehousing
• Distribution Centers
• Transportation/logistics

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Transportation Applications

• AutoMod has been used for
• rail yard simulation
• Norfolk Southern mixing centers
• Steel company train yard
• U.S. Navy explosives storage site (rail, ship,
  cranes)
• rapid transit
• Miami Metrorail and Portland TRI-MET
• ports
• Port of Singapore
• ships, tractor/trailer and agv, yard cranes, quay
  cranes

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DemonstrationA Rail Demo Model
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Topics

• The Challenge
• Example Simulation Modeling in One Day
• Whats in the AutoMod Toolkit?
• An Approach to Rapid Modeling for the Paper
  Switching Exercise
• Discussion

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The Challenge

• Rapid Model Development
• Model must be ready to run in days
• Data should be standardized as much as possible
• Rapid Experimentation
• Rapid Analysis
• Other aspects outside the simulation toolkit
• data collection preparation, ...

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Example Rapid Model Building

• Taco Bell template model
• model of auto traffic in parking lot, adjacent
  streets and drive-thru (0, 1 or 2)
• Taco Bell has applied the model to 80 sites
• They develop a new model in one day
• import CAD drawing and develop new layout
  (paths) of adjacent streets and parking lot
• enter site-specific data (traffic rates, ) in
  standardized format
• NO programming
• run and get standard reports (analysis may take a
  few days)
• Initial development took 6-8 weeks

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DemonstrationThe Taco Bell Template Model
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Whats a Template Model?

• Specific, narrow domain
• well-defined scope, boundary, level of detail
• Generic model
• everything is a variable, including the layout
• completely data-driven
• Standardized input files
• Standard output reports
• customized for the application (not standard
  AutoMod reports)

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Is a Template Model Possible for the Paper
Switching Application?

• Assumptions
• Man-machine simulator
• Needs to have an interactive front-end
• Humans provide the hard decision-making logic
• Model makes the basic moves, displays current
  state, tracks standard statistics, tracks history
• Model needs to replay and allow restart at given
  time
• Needs to run on a network
• multiple front-ends, multiple simultaneous users
• multiple models (or multiple copies of same model)

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Whats in the AutoMod Toolkit?

• MCM/MMS
• Generic modeling support
• Replay and Checkpoint/Restart
• Tracking History
• Presentation
• Other requirements
• standard inputs and outputs

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The AutoMod Toolkit MCM/MMS

• MCM
• Model Communications Module
• Facilitates messaging between models and other
  applications, such as
• Custom user interfaces written in Excel, VB or
  Java
• MMS (Multiple-Model Synchronization)
• Allows multiple AutoMod model to run together
• Simulation clocks automatically synchronized
• Works on 1 PC or over network
• MCM messaging to send entities or information
  model to model

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MCM/MMS Actual Applications

• MMS allows any number of AutoMod models to run
  together with synchronized clocks, and to pass
  messages
• USPS
• 3 to 7 synchronized AutoMod models
• simultaneous model development
• easy swapping of one mh design for another
• experimentation with an integrated model
• AutoMod AutoSched AP
• uses AutoMod to add mh and animation quickly
  without having to enhance the AutoSched product

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MCM/MMS - Overview

• Control system
• UI s/w
• Excel
• VB and Java UI
• AutoMod Models
• AutoSched Models
• Other simulation package

AutoMod Model
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DemonstrationMCM/MMS In Action
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What is MMS?

• Provides time management
• offers 2 modes exact and periodic
  synchronization
• models are event-driven and run as fast as
  possible, or with animation, run with a display
  step
• repeatable
• Provides message passing
• automatic synchronization messages
• model dependent messages
• message is any no. of integers, reals and strings
• message usually represents an external event or
  data transfer
• each model has a callback function to process
  external events

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What is MMS?

• Works on 1 PC or any no. over a LAN
• Based on sockets, so works with Windows, Unix
• On Windows LAN, MMS has low overhead
• Provides debugging support
• Ability to interact with all models while running
• Repeatable capability to repeat run for
  debugging by re-run all models, or only one model
  driven by a message file.
• Hardened, tested, used in large-scale industrial
  models
• Prototype in use for 3 years
• MMS available now in commercial release

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MMS Time ManagementExact and Periodic Mode

• In exact mode, the simulation clocks are
  synchronized perfectly
• only 1 model runs at a time
• appears as if all are running simultaneously
• MMS server controls which model runs
• In periodic mode, all messages are sent when
  desired, but are received periodically, say every
  10 simulated seconds
• between message updates, all models run
  simultaneously
• potential for large run-time gain
• downside is possible loss of accuracy
• suitable only for properly defined, loosely
  coupled submodels
• repeatable

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MMS Applications

• Interactive custom UI
• Excel
• VB
• Java UI

AutoMod Model
Ergonomics or Robotic Cell Model
MMS Controller
AutoSched AP Model
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Applications US Postal Service

• USPS Processing and Distribution Center
• currently 3 AutoMod models in the suite
• soon to be 6 models
• individual models for
• equipment (LPE, FPE, IBS)
• MH (conveyor, agv)
• Facility control (scheduling, routing, dispatch,
  )
• multiple model developers, geographically
  distributed
• each model can run standalone for debugging, V/V
  and initial runs and analyses

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Postal Model
Facility Control Model
Equipment Models
letters
AGVS
Conveyor
flats
parcels
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Applications Semi-Conductor(Presented at ASI
Symposium, June99)

• Integrated Mfg and MH Models for large
  semi-conductor manufacturer
• AutoSched AP and AutoMod Models
• AP model does facility control, scheduling,
  routing, processing
• has all the intelligence
• AutoMod model is simpler, MH only
• receives commands to move a lot from A to B
• notifies AP model upon delivery

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Applications Ergonomics

• An ASI customer (a simulation consulting firm)
  connected an AutoMod model to ergonomics model
  produced by another s/w company

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The AutoMod Toolkit Variables

• For path-based models (incl rail), a standard
  classification system for components and control
  points allows a generic model to adapt to new
  layouts
• main track, leads, ladder,
• control points can be variable

1 or more leads
Any no. of parallel tracks
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The AutoMod Toolkit Variables

• Generic logic to address the basic moves
• pull into track X
• drop N railcars
• pull forward past switch and back into track Y
• Conclusion One AutoMod model can work with a
  range of layouts

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Replay and Checkpoint/Restart

• Human-made decisions transmitted from the UI to
  the model can be recorded
• Allows play back of a complete shift or day
• Gives you a built-in way to do a presentation
• Allows checkpoint/restart capability
• Restart and play back to a specified point
• Pick up with interactive human decisions
• we goofed, lets back up 1/2 hour and try again
• true back-up of time not feasible, but re-run is
  fast when animation is off

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AutoMods Train Template

• Provides some support for typical train modeling
• automatic detection of head of train passing a
  point
• automatic detection of train clearing a point
  (such as a switch)
• dynamic acceleration and deceleration rates
• currently, its prototype but has been used by
  AutoSimulations consulting group numerous times

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Requirements for a Custom Interactive Front-End

• Model must be driven by a custom UI
• Standardized, pre-written
• Will it require some customization on each
  project?
• Standard model controls
• Pause/continue
• Animation on/off
• View control (zoom)
• Restart and re-run up to specified point
• Specific commands for train control
• Displays system state and standardized output
  reports
• Easy, quick to learn and use

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Standardized Inputs and Reports

• How feasible to have standard inputs across the
  range of anticipated applications?
• Train arrivals
• Train characteristics (no. types of railcars)
• Speeds, acceleration, braking, delays
• ...
• Are there standard outputs?
• Can custom outputs be added quickly?

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Standardized Set of Decisions

• The logic behind the decisions is provided by the
  human users
• makes model simpler
• makes a generic model possible
• But can the actual decisions (or commands) be
  standardized?
• Pull into track X (one of several parallel
  tracks)
• Stop with engine at point Y, or Stop with last
  car at point Z
• Drop last N railcars

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Limitations

• Model would move trains, drop off and pickup
  railcars
• Animation would display trains and railcars only
• Other activities would be represented by time
  delays and would not be shown visually
• automobiles unload and re-load (mixing center)
• container movement, unload and load

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Summary An Approach to Rapid Modeling for Paper
Switching

• Same model running on multiple machines
• synchronized in simulation time
• runs real time, faster or slower
• color-coded animation shows current state
• allows different users to view different parts of
  yard and different reports
• Standard interactive UI with model control and
  reporting

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Discussion Q A

• Is it feasible? Is it cost effective?
• Can the movement logic be modeled in a generic
  fashion?
• The hard logic comes from human participants
• The model responds to commands
• Other modeling activities - data collection,
  analysis, etc - must still take place.