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Thank you for the quick and detailed response! I see the error I was making with work schedule and have tested it on one server, it seems to work as intended. Since each of my servers have a different capacity, would I need to create a unique work week and unique day type for them all? Or is there a quicker work around? The manual inputs for the date time are a great work around, I'm only modeling for a few years so I don't mind inputting a few dates. What I mean by there being no buffers is that no server can have a queue. I used a list for selecting the destination on the output node of each source (total of 8 ) where it's a hierarchy. It can go to a select number of servers and if all of them are full it goes to a dummy server of infinite capacity that exits the items to an overflow sink.

You want to make the servers have a Capacity Type of Schedule and follow the default Standard Week. If you don't want to give them a lunch break, just change the definition of the Standard Day. Leave the default Off Shift Rule of Suspend Processing. The easiest approach for arrivals is to have a Source with an Interarrival time of 4.33 weeks (or 4 weeks) and an integer random distribution for the Entities Per Arrival. Doing a "first Monday" is possible, but a bit complicated because Simio time does not have the concept of Month because months are of varying size. You could probably specify the initial Time Offset to be early in a month, then maybe make the interarrival time be something like DateTime.DaysInMonth(DateTime.Month(Timenow),DateTime.Year(TimeNow)) which would make the next arrival be exactly one month later (same day of the month). When you say you have no buffers, what do you mean? If an entity arrives when all servers are busy, should it be balked (possibly disposed) or should it wait somewhere like on the server input node, on a path or in the Source output node? If the above arrival approach isn't exact enough, you can put exact arrivals in a data table. The arrival time could be specified at any exact datetime you desire and still have the Entities Per Arrival be a distribution.

Hi all! I am simulating a facility with nearly 40 servers, each one starting with some entities in the input node at initialization and having a different capacity. Each server has a 0 input buffer capacity. My entity creation is currently set to having an interarrival time to be 4.33 weeks (1 month) with a random number of entities created. Currently, it runs 24/7 and does not care about the time, but I want to incorporate that. How can I make it so that the entities arrive once a month, let's say the first Monday, at 8am? How can I make it so the servers are only processing between 8am and 4pm Monday - Friday? The work schedule doesn't seem to work for me, but I could be doing it wrong, since I have a 0 input buffer, which I can't change as it's part of my routing logic for overflow. I would be happy with using timers or a process logic if someone can explain it to me. Ideally, the entities only arrive when it's during the working time, and the entities remaining after 4pm are just put on hold until 8am the next day. Thanks in advance!

Hi, there is a simple approach you can use. Use Connectors between the queue server and the desks. At Buffer Logic of the Desks, change the Input Buffer Capacity to 0. Create a List with the Input nodes of the seven Desks. On the Output of the queue server change Entity Destination Type to Select From List and the goal to Smallest Value. Keep the default expression. It should work fine.

Hello all I am relatively new to Simio and DES. I am trying to model a pallet conveyor. It is a closed loop conveyor. I use the "vehicle" as the pallet that loops around the conveyor. At the source the part (default entity) is loaded on the pallet. At the sink the part is unloaded. The problem that I am encountering is that the vehicles from time to time pile up at the sink, then after a certain amount of time they continue back to the starting point "Source1". This happens more the more I increas the "initialnumber in system" of vehicles The transfer-in Time for the sink is set at 0. At the model trace I read this for the "Input@Sink1" : "the in Token waiting at VisitNode step for '1' other processes to complete." I would apreciate any advice. Many thanks! Vehicle_stuck_at_sink.spfx

Hello everybody, I'm trying to make this work but I cant Type/Conteiner BinBig BinMed BinSmall Product1 1 1 - Product2 - 1 1 Product3 1 - 1 Product4 1 1 1 I want to make a node where these entities (Products and Bins) are convined in one batch, I try to use a process based in decitions and search.. the file is attached if you wanna take a look on it.. (the product have to be the parent) OptimoContenedores2.spfx

In addition - Based on error message, the destination selection step seems to be trying to use a reference table, (used at source output node), despite the particular node list being specified in the routing logic for the node in question, (i.e. Output@QC2 - see below). Thanks again.

Hi there, I'm very much a novice, but currently leveraging the logic in VisitAllServersInAnyOrder simbit to ensure an entity visits an entity is never reworked more than once. I've updated the model entity with required state variables and created a "MyServer" to create the "HasEntityVisited" etc etc. I'm using the "Candidate.MyServer.HasEntityVisited==False" logic for the selection condition in the output node routing logic. However, whenever I run the model I get the error message "Referenced definition type "MyServer" does not match executing type "BasicNode". I've gone over and over the various elements and compared to the working simbit, but can't identify the issue. Any help would be greatly appreciated. Thanks in advance. Garrett

Hi I've got a model where the situation is like this: 1. 3 Worker: W1 W2 W3 2. 3 Server: S1 S2 S3 On Monday (work schedule), W1 will work in S1 in the morning and work in S2 in the afternoon. W2 will work on S2 in the morning and S1 in the afternoon. But on Tuesday, W1 will work in S2 in the morning and S3 in the afternoon. W2 will work in S3 in the morning and S2 in the afternoon. The server properties in the secondary resource are "select from the node list." But since the node list for S1 and S2 contain both W1 and W2, and they both have the same hour of working (4+4), when the S1 server seized the resource on Tuesday morning, instead of W1, W2 got allocated instead( W2 should be in S3). I have tried: 1. Using server selection goal to " smallest distance," but it didn't work since the worker will keep swapping the room every day 2. Giving each worker a new initial value and setting the selection goal to "smallest value," but they still have the issue. 3. Try setting idle action for the worker to stay at the node, but sometimes the worker will go to the wrong destination from the first entity, hence no one working in the other room. (2 worker stay together) Is there any method to realize this idea? Thanks in advance

This helped in some applications, especially use cases where multiple servers are in series and I need the operator to focus on the start or end of the process. Thanks! However, when servers are in parallel the operator tends to run back and forth between them. If I were to assign a higher priority to one line, the worker would focus on that line only. i.e. if he empties the que of parts in the input buffer of Server 1, he goes down to work on only 1 part at Server2 before going right back to Server1. Rather, I'd like for the operator to clear all parts in the que at Server1 before walking down to Server2 and vice-versa. I've tried doing this through process logic however I get stuck trying to evaluate which server the worker is supporting.

Thank you for the quick answer! Yes I know the ABC Costing Calculation in Simio, but I forgot to add, that I want to divide the total transport costs among the individual components that are transported at the same time. I think it would work with the calculation: TransportCostRate / TransportQty * TransportTime , so I just have to track the transport quantity for example with MyVehicle.RideStation.Contents. And my small model is just a example. My goal is to set up a cost analysis tool with calculation of transport costs, bufffer costs, processing costs, ... for finished production models. And for example the buffer costs, i want to use more specific cost rates (footprint dependence for example, ...) The disadvantage of my custom way is that so far I can determine the costs only at certain points (for example pick up and drop off) in time and not "continuously" as it is now with the automatic calculation. Or do you know if there is a way to adjust these "custom" times so that they are also calculated continuously?

Hi! I don't think you need to save those times stamps on MyVehicle. I would suggest you to use processes that triggers when the entity leaves the Output Buffer of the source and enters the Input Buffer of the server. To do that, create two process with the corresponding Triggering Event Name: Source1.OutputBuffer.Exited or Server1.InputBuffer.Entered, saving time stamps directly on the MyModelEntity.

Updated version where slug conveyor can be used as a standalone slug build conveyor. Set the Merge property on the conveyor to False to use as standalone conveyor. Ending node for slug section should be a slug node. Make sure that the initial traveler capacity of the slug node should be 0. ConveyorLibrary _V2.spfx

ConveyorLibrary.spfx Simple conveyor library with a merge controller, slug conveyor, Slug Node and a Photo Eye. Library has two example models. A MergeControllerModel and a PE_ExampleModel. Merge controller,Slug Conveyor and Slug Node are used together to develop a slug merge. ConveyorLibrary.spfx On the slug conveyor you can specify the size of the slug. Slug node controls when the next slug is to be released. As soon as last entity in slug crosses the slug node it will send a signal to merge controller to release the next slug. Ending node of the slug conveyor has to be a slug node. Conveyors before and after slug conveyor are regular conveyors. These objects have not be extensively tested. These can be used to develop other conveyor related objects.

A basic photo eye object that can be used with conveyor belts. Photo eye is based on a transfer node object. It collects statistics on time in blocked state, cleared state and throughput. Transfer nodes on entered and on exited add on processes can be used as on blocking and on clearing add on processes. Photo eye has properties to define the delays for on blocked and on cleared. Photo eye will wait to complete on blocked delay to execute on blocked add on process. Similarly, photo eye will wait to complete on cleared delay to execute on cleared add on process. PE_Library.spfx

Hi all, I am building a simulation of a system with multiple separators which MemberOutput nodes two different routing policies can occur: 1. Standard Policy In the 'Standard Policy', each separator has its dedicated transporter assigned to it and entities arriving at the MemberOutputNode can only select the defined transporter. To this end, a DataTable has been constructed. 2. Power Hour policy In the 'Power Hour Policy', operations are shifted into a higher gear. We select a maximum number of three nearest transporters whose ride request is 0 and include them in the DataTable which specifies the Transporter Selection. Entities arriving at the MemberOutputNode can now request rides from any transporter in the DataTable. I tried to reference to a DataTable called 'TransporterSelection.EPT' in the Transport Logic of each MemberOutput Node. Each value in the EPT column is cross-referencing to a DataTable in which I try to assign the MemberInput Nodes as a Node Reference State Variable of the Transporter (EPT). Is there any way to dynamically assign more (or less for that matter) Transporters to a TransferNode? Hope that anyone knows how to do this! Cheers, Toon

Hi @jzhou, how would this work if I want to refer to the MemberOutput Node of a separator in an expression? I get lost at the following expression: Entity.Location.Parent.Node.AssociatedObject.Separator.Output.[what comes next?]

Hello River, I downloaded your files. The Gate512 was missing. I removed the information in the "30 Departure.xlxs" file that I can run the model ;-). Generally I understood how it works. Answer to your first question: I think you mean these two ways, right? From the left and from the right. In this case I saw that you used the "Routing Logic" in like all Transfernodes. The Outbound Link Rule is "Shortest Path" and you set the "Node Name" to "Input@Takeoff" Simio is using everytime the shortest link path now. Like in the screenshot below: In my opinion it would be better to set the destination once after the Entity got created in the Source for example :-). There are different ways to do that. In your model I removed all Routing Logic in the Transfernodes and used the Routing Logic only in the Output-TransferNodes of the Sources. In Simio you need only to use one time a SetNode-Step or a Routing-Logic to set the destination of an Entitiy and Simio will follow the paths or travel in the FreeSpace. You can use for example a NodeList with 2 different destinations and this Routing-Logic: With the "Selection Goal" Random Simio will randomly choose the destination from the NodeList. I uploaded you your model with the changes as an example: Problem on the taxiway version 17A.zip What did I changed? 1) I removed the Routing Logic in all TransferNodes. 2) I added new Routing Logic to the TransferNodes of the Output-Node of the Sources. 3) I added a NodeList with 2 new Nodes. 4) In the two new Nodes I used a Nodes-Entered-Process and a Transfer-Step to transfer the Entity to the Input of the Sink. Answer to your second question: You can change the destination of an Entity any time. In the Path (Link) you have a function called "NumberTravelors" for example to get the number of travelors currently on this path. So you can use a Expression like "Path123.NumberTravelors < 2". This can be used to decide if a way is full allready that the other way get selected. Or you can use a Integer-State and count up and down. I would use a Node-Entered-Process in the last possible node with a Decide-Step and two SetNode-Step in this case :-). I hope my answer will help you. When you have any other question, you are welcome! Best regards Pascal

FullGate version 17 (both side take off).spfx We encounter few problems: 1. Why the plane( entities) only go to one side for waiting to take off but not both side used? 2. Any fomular can i add into the simio? The plane will choose which path to go on the taxiway. Such as the plane on the Node 82 if the taxiway A(path 179) had 3 plane waiting but taxiway B (Path 160) had 1 plane waiting, than the plane will choose taxiway B to wait for take off. Gate.xlsx 30 Departure.xlsx

Thank you Dave! Inspired by your approach, I defined two Node Reference State Variables for the Entity: EndDestination and NextNode. In the model Processes, I first determine the Entity State Variable EndDestination based on a DataTable with probabilities per destination node. Then, at routing decision points, I have created processes that evaluate the EndDestination node and set the next node for the unity based on that. Although it requires a bit of 'hard modeling', it works like a charm! Thanks

I have attached a simple model using model states to illustrate. I think it should work in a similar fashion using entity states. First, I define the states: Then use those states as Sequence destinations: Until you provide each of those states a value, the Sequence will make no sense and the entity won't know where to go. So on the Source I use an Assign to initialize all the values. This will direct the entity sequentially through Servers 1-4, and then to the Sink: Finally, just to illustrate the technique, on the output node of Server3, I interrupt the normal sequence by Assigning it to instead go to Server5 as its 4th step: If you convert these states to Entity states instead (I was just lazy), I think it should work the same but allow you to selectively override any Sequence Step at any time. UsingStatesInSequences.spfx

Hi David, I am trying to get your option 3 to work in my model, as the solutions sounds brilliant. I created an Add-On Process that probabilistically assigns destinations to the Entity and by assigning the destination node to the Entity's State Variable MyDest. In the Routing Logic, I've set the Initial Sequence to the sequence table called Routes that holds all possible routes. However, the entities now only follow the first sequence Routes (Input@LoadingDock9, Input@Sink_HTB), whereas Entities with the destination Input@Sink_RTM should follow the sequence Input@LoadingDock10, Input@Sink_RTM. How can I let the Entity follow a specific sequence from my Sequence Table Routes?

How can I set a safety distance between with other entity . e.g. Transfer Node 79 entity is will impact with others, how can I set a safety distance on every entity?

Thank you for responding - in that configuration, does that mean I need 100 excel sheets? Right now, I have 100 rows that have the different experiments I want to run, and all the values needed for the node-lists / transporter-lists and entities to be used Thanks for your help!

To make an entity wait until the runway is free what you could do is set the Initial Traveler Capacity of the Runway path to 1. This way entities will wait at the node before entering the path. I did not understand the first question, but if you need entities to visually appear behind one another, set Allow Passing to False on the path. Alternatively, you could use conveyor instead of path to make entities allign and respect some distance. Hope it helps.