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Valero Energy is needing to hire a Business Intelligence Analyst – Simulation Developer at our San Antonio, TX Headquarters. The position will support the Transportation department by developing data analytic, algorithm, simulation and optimization models. One of the key responsibilities will be to develop refinery logistics simulation models using Simio Enterprise software. Applications can be submitted here: http://valero.taleo.net/careersection/jobdetail.ftl?job=22001OQ&lang=en

The Transportation Library provides a collection of objects for modeling cargo transportation using trains, trucks, boats, pipes, and robots. The Tanker object is sub-classed from Vehicle and used to transport discrete and flow entities between node locations. The Tanker has all the same functionality as Vehicle, except it has been extended to have weight and volume limits. In addition to standard discrete pickups and drop offs, the Tanker can also perform continuous flow pickups and drop-offs using a Dock object. The Dock object provides support for flow into and out of entities and vehicles (like a Tanker or HopperCar) supporting flow. The Dock is seized/released by the Tanker/HopperCar during loading/unloading operations at the Dock. The Dock may also follow a Work Schedule. The Pipe object may be used to model continuous flow through a fully filled pipe. In contrast to the FlowConnector the Pipe requires time for the flow material to travel. The Pipe can be used to connect flow between Tanks or between a Dock and a Tank to more accurately model the travel time of material flow from one location to another. This is particularly useful in applications where heavy liquids are transported over long distances through a pipe. The Railcar, Locomotive, and HopperCar objects represent various types of train-related vehicles. Train movements are modeled by defining a track network comprised of ControlNode and Track objects, over which trains move. A train is a linked sequence of RailCars, where the first RailCar in the sequence is a Locomotive. The RailCar can represent a wide range of train cars including freight cars, cabooses, passenger cars, etc. In addition a HopperCar is special RailCar that is provided to support fill/empty operations at a Dock. The HopperCar is a RailCar with the added functionality of a Tanker. The RailCars can be linked together in any order; for example a train might contain two or more Locomotives. The RobotBase, RobotLowerArm, RobotUpperArm, and RobotHand objects are the components used to model a multi-axis robot. The RobotHand is specified as the transporter and the movements of the other robot components are automatically calculated to support the required hand movement. Like all Simio-provided libraries, this library is open so you can look at how it was built, learn from it, and subclass your own objects to improve them. The Transportation Library was created totally by deriving its objects from other Simio objects and then supplementing with Process Logic. No C++, Java, or other user code was required to write or use these objects. And you can also customize the behavior to match your own needs. Unlike our built-in libraries, this is not fully supported (although we can provide some help) and we may not continue enhancing it, particularly if we decide to build this capability into the base Simio products. We are anxious to receive your feedback on this library. Here is a zip file containing the library, documentation, and a few examples. Updated 2014-01-23 - The InputFlow node's Initial Maximum Flow Rate property on the Dock object was not being used to regulate the rate the Tanker was filled. This has been Fixed. The rate the Tanker is filled can now be adjusted using the InputFlow node's Initial Maximum Flow Rate property. Updated 2014-02-17 - Updates to the Tanker and Dock objects Updated 2014-03-17 - Updates to HopperCar and Locomotive behavior when dropping off. Also bug fixes. Updated 2014-03-19 - Bug fixes - Loaded car no longer takes off on its own after loading, but waits to be picked up by the locomotive and The Loaded add-on process now runs after the loading is complete. Updates 2014-04-07 - Added ability to allow a RailCar to request a Locomotive. See example DropPickTrain_DetatchToLoadUnload.spfx Updates 2014-04-17 - Bug Fixes to previous update Updates 2015-03-23 - Bug Fixes to previous update TransportationLibrary.zip

Hi, I am working on a transportation model where the vehicle drops off customers at a station and is parked at the node until it is further required. Is there a way to limit the number of vehicles a station can hold? Thanks, Amit Sinha

Hello I am working on the road transportation problem and I use the vehicles. I have a couple of questions about the vehicle's features and usage. 1) How can I define an Off Shift for the vehicles? 2) How can I extract the total amount of times or distances that a vehicle is traveling empty (without load)? 3) Is there any way to create any response regarding the average performance of all the vehicles used (i.e. average idle time of the vehicles) to perform an experiment? Thanks, Amin

Dear Simulationists, I am trying to model a manufacturing cell consisting of a metrology station, CNC machine, and an airblast station. Each processed batch contains 3 different parts. The batch is inspected in the metrology station, then is mounted on the CNC where the first part is machined. After the first part is machined, it is then taken out of the CNC machine and transported to the airblast station, and after that to the metrology station and the finished parts store, while the CNC machines the second part of the batch. The same is repeated for the second and third part of the batch. After all three parts are machined, the plate used as a fixture for the batch is also processed on the CNC, followed by transportation to the metrology station and the plate store. There are defect rates of different magnitude associated with different operations. My idea was to represent each of the operation steps as separate servers (4 CNCs, 4 metrology stations, 3 airblast stations) and create a process logic that assigns a single shared processing capacity on all servers performing the same function. For example, this would not allow the second CNC to start operating if the first is already operating. I have been struggling to define this process logic for three days now, and as my desperation levels grew progressively higher, I decided to seek assistance from the experts in this forum. I would deeply appreciate it if you share your ideas on how this process logic might look like, ideas about more efficient methods to model the scenario and any general feedback or suggestions! Thanks, Hristiyan

Dear Simulationists, I am trying to model a manufacturing cell consisting of a metrology station, CNC machine, and an airblast station. Each processed batch contains 3 different parts. The batch is inspected in the metrology station, then is mounted on the CNC where the first part is machined. After the first part is machined, it is then taken out of the CNC machine and transported to the airblast station, and after that to the metrology station and the finished parts store, while the CNC machines the second part of the batch. The same is repeated for the second and third part of the batch. After all three parts are machined, the plate used as a fixture for the batch is also processed on the CNC, followed by transportation to the metrology station and the plate store. There are defect rates of different magnitude associated with different operations. My idea was to represent each of the operation steps as separate servers (4 CNCs, 4 metrology stations, 3 airblast stations) and create a process logic that assigns a single shared processing capacity on all servers performing the same function. For example, this would not allow the second CNC to start operating if the first is already operating. I have been struggling to define this process logic for three days now, and as my desperation levels grew progressively higher, I decided to seek assistance from the experts in this forum. I would deeply appreciate it if you share your ideas on how this process logic might look like, ideas about more efficient methods to model the scenario and any general feedback or suggestions! This is a repost of the thread from the public forum to allow file attachments. Thanks, Hristiyan

Any entity traveling on a path at a faster speed than the entity ahead of it with catch up to that lead entity, and continue following it as long as the path Passing property is False. I have used this as a quick way to model things like a vehicle that tows several carts around the model. You might also look to the Trains or Transportation library that is in the shared items folder.

In a model of a bus transportation system,how would I place a certain time period between buses before they get into service, so they won't arrive at transfer nodes concurrently? I thought of placing a delay in "RunInitialized" process, but the delay should be greater for subsequent vehicles, and I don't know how to determine if the vehicle is the firsty, second, third bus, etc.

Hi everyone, Working on a model that should interrupt a delay function in a different process. The interrupt in that manner prevent the execution of a process. Tokens for this process are generated when an entity is being created, and destroyed (by means of the interrupt) when the entity arrives at its destination. The entities are being transported by means of a vehicle, so sometimes not all the tokes are destroyed since some of the tokens are still in the delay (waiting for transportation of the vehicle). The problem that I am facing is that the tokens are not destroyed in order, this pattern seems rather random. It even occurs that tokens with a very low ID number are still in the delay when this should not even be possible (they should have been destroyed long ago). So the question is, does Simio interrupt tokens within a delay in the correct order or randomly and how to ensure that this occurs correctly? Thanks !

The Transportation Library has been updated with a few bug fixes. Sprint 7.114 or later required.

The Candidate Library is special library used to stage objects before moving them into the Standard or Flow Library. At some future date these objects may be moved “as-is”, or they may have some design changes before integrating them into the Standard/Flow Library. We encourage users to provide feedback on these objects so that any suggested changes can be reflected in their final implementations. This version of Candidate Library has two objects: a Pipe and a Server. The Pipe is targeted to be added to the Flow Library and is an updated version of the Pipe in the Transportation Library. It is useful for modeling flow between two FlowNodes where travel speed and volume are important considerations. An example model is included (SimplePipeFlow) The Server is targeted to replace the existing Server in the Standard Library. This new Server object has the exact same functionality as the existing Server but also supports multi-phase activities. This is useful in modeling situations where a number of activities take place at one location and each activity requires different resources. These activities can be specified either directly on the Server, or through the use of relational tables. This makes it much easier to model multi-phase activities such as found in healthcare, complex batch operations, or assembly operations. An example model is included (MultiphaseServer) These objects have been made part of the Flow Library and the Server object in the Standard Library.

I'm trying to model a transportation behavior where for every 20 entity(shipping size) accumulated at a node, I want a transporter to come pick the entities up (exactly 20 entities). However, since the requests are initiated from the same node, a single transporter comes and picks up everything if there are more than one party at the node (one party = 20 entities). But if I have two parties accumulated at the node, I want two transporters. I know setting the transporters' capacity to 20 will solve the issue, but the shipping size property can be different among nodes and I'd like this behavior to work even if the transporter's capacity is set to infinity. Any suggestions? Thanks, Selin

Hi Glen, I feel your pain...hahaha....and please whatever you do stay away from Math.Epsilon for this... Lets have a look at this based on the impact that this problem will have on a Tanker object (Transportation Requests) for I think the ultimate generic solution for all FlowContainer elements should be based on this logic... 1. There can always be a positive or negative residual around a specified level (0.0001 + 16000 MT - 0.0001) in a tank (cap of 25 000 MT)... 2. If there is a positive residual, there will be an entity in the output regulator's flow request queue...Thus an erroneous transport request will be logged.... 3. If there is a negative residual, there will be no entity in the output regulator's flow request queue...Thus transporter will be stuck as it would not have reached its load level of say 16 000 MT.... Based on these assumptions we have discarded the problem with the residual in the tank, which kinda really can be disregarded...and redirected the problem to the Flow regulators where the actual residual problem becomes more evident... What I typically do is set the variables on the monitors watching the transfer, to the specified level WITH plus or minus 0.0000000001 depending on the transfer performed. The monitor will thus trigger the end transfer process just before the specified level, and then I simply adjust variables back up by means of rounding up to a higher decimal. (0.0000001 instead of 0.0000000001 ) ALTHOUGH, you HAVE to clear your regulators' flow request queue before and after ANY transfer if you use the above option. This brings another catch 22 for each time you do this, a new entity instance is created. To be quite honest, I would program in hard code a function that executes after every transfer to round the value up to a higher decimal. i.e. perform the transfer in the code with the monitor to a level of variable - 0.00000001 (HARD CODE) and then have a function call after transfer to cut some decimals and round up back to the specified level which is at a higher order i.e. 0.000001. Truly think the solution to this conundrum lies close to this logic and its difficult to explain the on the blog...Perhaps we can set up a skype conference call and I can demonstrate as well as enlighten you to ALL potential pitfalls and workarounds we have discovered pertaining to these transfers...

Thing here is Alan, if you look at the example included in the transportation library, you will note that they assign volume = 5 and weight = 5. Thus if you want to use this transporter for weight or volume you have to make a double assignment each time. Throw some other conversions such as weight = metric tons and boom, transfer time goes out the window. There is also the density variable and flowcontainer fringe conditions on top of that. Bottom line, I can break this transporter so not worth using till fixed.

Very powerful... I like the transportation aisles which allows for some limited obstacle avoidance. Is it possible to combine multiple bays with different transportation aisles but only use one bridge, such that the transportation aisle changes as the crane traverses to its destination?

I updated the library in the above post. This version is "CraneLibraryV4a.zip". In this version, I fixed both issues. 1) There needs to be a Math.EPSILON delay on first entity arrival to provide time for crane initialize. Update your source and add a "Math.EPSILON" delay to the TimeOffset property. This will provide enough time for the crane to initialize. I added a warning message to the library if there is a reservation request for the crane and the crane is not done initializing. 2) The library was assuming that a Transportation Node was defined on the bay. In your bay, the Transportation Node was NULL. I updated the library so the Transportation Node property can be NULL.

Attached is an updated crane library. This version includes the following changes. 1) Crane Specific Transfer Bridge List.....Each crane can use a different bridge list. This gives added flexibility and helps avoid blocks. (e.g. Crane A within a bay can choose Bridge A and Bridge B while Crane B can choose Bridge B and Bridge C). 2) Animation for the seizing of the Cross Bay Transfer Aisle zones....Now when a crane seizes the cross bay transportation bay zone, the zone is display as a dark grey. 3) Bay is no longer visible. This allows for status objects, status labels and symbols that are placed on the floor to be visible.

The next three-day Standard Simio Training class, open to the public, will be held on August 14-16. The classes will be held in the McLean VA area, convenient to Dulles and Reagan airports and local transportation. Also plenty of hotel accommodation in the area and nearby downtown Washington, D.C. and all its attractions. The fee for the class is $1,485 per attendee. More information on Simio training: http://mosimtec.com/services/training/ Contact me if you have any questions or would like to register. Best, Martin