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Hello everyone, I have a server which can potentially have many entities waiting in the input queue. All these entities have different priorities (as a model entity state variable). I want to retrieve these values to then select the highest one and put it on a status label to track this during the run. Is there an option to do this? Regards, MF

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!

Ok, I think that I sort it out. I am not very confident of what I do but I think that it works now: I changed the Vehivle "Routing Logic". Idle action: Go to home AND I changed for every server, secondary resources: Earlier it did not work because the vehicle was stuck at the sink waiting for an entity to be available at the source. The idle action for the vehicle was to "Park at home"..

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

Updated version with prime on infeed. Filler won't start until you have enough entities on the infeed conveyor. IndexingPlate - V4.spfx

Ok I can do a trace and see what I find. Also, I do have different entity/job types getting processed. In my routing tables, I do have the entities specified in the table. I'm trying to use the "ChooseAlternateSequence" simbit as a reference. Is it possible to do this if you have more than one entity type?

Hello, I'm having strugles trying to configure the setup for the next process: some entities have a diferent processing time and setup time, before to enter to be processed in the workcenters, the workcenter have to be cleaned. I looked the simbit, "ServerWithSequenceDependenrSetup" but I'm confused with the configuration of the processing task. I dont know why we have two lines and o why only one have associeted the change-over matrix.

Hello there, this is my first post here and I hope someone can help me with my problem. I´m quite new to Simio and working on my first project. I have some "return entities" that are considered "bad" at the end of the production. So they will get collected in a server which is used as a storage and get returned to the factory every 24 hours, to get reworked, if there is capacity left. Now, I want to check if there is capacity left in the destinated server and in best case, reserve the needed capacity before, before I route these entities towards it. After the entity arrived in the server, the reserved capacity should get released again. I couldn´t find a good example here in the forum or via google search, as in the SimBits, how to solve this the correct way. Maybe someone here can give me a tip, how to. Thanks in advance. Aljonator

Hello, I have two concerns. In one of my small models I want my transporter to make a round and pick up the entities at the different locations and bring them to a destination (Server1). In addition, I would like that the individual times are measured with a state MyModelEntity.TmpStart and MyModelEntity.Duration, in order to calculate afterwards with a transport cost rate the cost for each individual part. Unfortunately I'm getting desperate with this and getting various error messages, does anyone know how to implement this? Best Regards, Gashi

First of all, Thank you so much for the answer in advance, but could I bother anyone who answers with some example model or picture of the method I am still new to SIMIO, so I am concerned about following the advice correctly. 1) Let's say every day I have X number of people arriving( using distribution to generate numbers outside SIMIO randomly). This is the shop where people visit from 8.00 to 20.00 every day with different visit rates per hour (example as below), and I use X to time to this percentage so I can get the exact number of visits per hour. The problem is I want to make an arrival interval random with some sort of function/distribution or table(excel calculation), not a stable arrival rate. My idea is random from 0 to 1 and gives the random number (Y) to match with X outside SIMIO and put the whole table in, but I wonder, is there any better method than this? 2) The second question is about two entities from different sources, A and B. A and B will go through the same server for three servers, but after server 3, one will go to 4, and one will go to 5. Can you give me any advice on how to do that

Hello everyone, I'm thrilled to share that I've successfully established my simulation model and conducted extensive verification and validation. Now, I'm ready to take the next exciting step: experimentation! While I've made considerable progress, I've encountered a minor setback. It seems that for certain scenarios, the response 'AverageWaitingTimePerTruck' isn't displaying any values. Interestingly enough, this issue only arises when conducting experiments with higher throughput values. The response is defined by averaging the tally statistic 'WaitingTimeBeforeReloading' of the Truck Entities in my model. Have any of you experienced a similar situation before? If so, I would greatly appreciate your insights on resolving this matter. Thank you in advance for your support! Best regards, Toon

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

Hello, I am writing my master thesis on production system design with simulation modeling. I have designed two models in Simio - one for current production system and one for optimized one. They are both designed in a correct way and they work as they are supposed to. The only difference between them is in path lengths. The difference between results from optimized and current system should be 3 - 5 % but for some reason I get all of the results identical to the last decimal place after running an experiment. I have attached a picture of my path properites and travel logic of entities. My guess is that for some reason path length is not being considered in the simulation. If anybody has any ideas what could be wrong, i would really appreciate your help.

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

Well, there are two problems in your model: First, there are many gates that are not following the data table. Second: every gate should be on the Gate table, regardless if they will have flights or not. If not, they will create entities on every single arrival of the departure table. You have many gates that are not included on Gate table.

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?

Hi Nicolas, I would investigate the Server property called Initial Capacity. This sets how many units of capacity are going to be available for the Server. You could also change this during the run by Assigning the Server's CurrentCapacity State Variable. I suggest checking out the SimBit titled "Worker Uses Work Schedule". You can access the SimBits in the Support ribbon in Simio. In this SimBit, I recommend changing the Initial Capacity for the Servers. You could set them to '6' or any value. When you run, you will see that the entities only move into the Process Station when they have successfully Seized the Secondary Resource. So even though there is 6 units available only 1 will be use when the Worker is able to process the entity. You can also experiment with giving the Worker a different Initial Number In System value so there can be more Workers. You will still see the same behavior; the number of entities that move into the Server for processing will be the number of Workers that were available to be seized. Happy Modeling! Liz

Hi everyone, I am trying to model entities moving from 10 origins (sources) to 10 destinations (sinks). The entities are simultaneously created according to a certain mix (Entity1 (85%), Entity2 (10%), and Entity3 (5%). However, the number of entities created per event is according to a certain distribution. There is an OD-matrix that captures the number of entities moving from origin to a specific destination. Let's say there are 10 destinations, than the destinations of the Entities are determined according to the OD-matrix: Entity1 and Entity2 can move to any of of the sinks. Entity3 can only move to one specific sink. One solution I came up with was to add weights to Connectors and assign destinations using TransferNodes, but I think that this is very inefficient. I then started to work with DataTables, but I cannot figure out how to probabilistically assign the destinations of the entities. My question is: how to model the probabilistic destination assignment of Entities using DataTables in such a way that it is relatively easy and flexible to add or remove Sources/Sinks? I have added the model for you to see, I hope that you can help me! Many thanks in advance Simple_OD_creation.spfx

This is problematic in Simio because Simio considers only entity length (not width) and only when on a Path or Conveyor. I think the first thing to do is fix the nose to tail problem. If you happen to use Conveyors to model this, there are built-in features to manage spacing while stopped and different spacing while moving. But unfortunately Conveyors are limited to a single direction, so are perhaps not appropriate if this is a bi-directional taxiway. If you are using Paths, you can fix this by making each plane longer when you draw it. For example, if you are drawing a plane that is 50M long and you want it to stay at least 10M behind the plane in front of it, place a nearly invisible dot about 10M in front of the plane's nose, making the total plane length (including safety spacing) be 60M. Although Simio will still put the entities nose to tail, there will be a 10M safety spacing between the physical planes. The problem of conflict at merge points is a bit more tedious to fix. I'd recommend a resource-based approach, like illustrated in the SimBit in Merging Conveyors Controlled by Gate. You can use this approach even when using Paths.

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!