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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

I second this idea. If we can directly assign string name to a object-reference state variable, then use the object-ref state variable as the Object, it will be a lot helpful. String concat is a very good one, for example , ModelEntity go through NodeA, we define its next destination as NodeA_a ....

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.

Hi I have an entity that is moved through the network via vehicles. The vehicle will drop of the entity at the first server which then gets processed through two servers. I would like to use the vehicle that dropped off the entity at the Input to the first server to be used to pick up the next entity at the output of the second server. Is there a way to save the exact Vehicle that was used and specify that as the Vehicle to use at the second pick up point? Hopefully to a global variable and not to the entity (in my actual model, the entity going in to Server 1 is not the next entity coming out of Server 2). At the moment I am using 'Reserve Closest' as the reservation method at Server 2. I know that is incorrect, but I'm not sure how to setup this up using the other methods. In the attached model, process works for the first entity, but does not for the second entity onwards. Due to other limitations in the model, I need to have the Vehicles to 'Remain in Place' during idle. Thanks in advance for the help. SpecificVehicle.spfx

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.

Happy new year! One thing that I noticed is that with this model, the server never have a state of "blocked". I increased the processing time of Server2 and added a status pie to Server1. The server 1 is either Processing or starved, but never blocked according to the pie. But it should be blocked part of the time since I increased the processing time of Server2 to force this. It looks like the Server1 only accepts a new item to process if the path between Server1 and Server2 has room for at least one more vehicle. So the time that it should be blocked is considered as part of the "Starved" instead. I tried to figure out why this happens without success. Anyone knows why this happens? I attach the model to the post. Thank you! Input Server1 not blocked.spfx

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

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 i'm the simio user in south korea i want to make my model flexibily. My model has vehicle and elevator The overall process flow is vehicle take entities to server1, After vehicle arrived to server1, elevator take entities and go to every destination. To work well, Three things are needed for this trend First, i want to do if the vehicle comes to server1 then the elevator goes to upstair Second, the vehecle has to wait until the elevator after been to upstair and arrive to server1 Third, repeat the two steps. how can i solve the problem this model in Model2, not Model1 1veh1eleModel.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.

I want to build a simple repository model,as the Picture below. And there are two Funktions, that i donn't know, how to implement. The first Problem is: I hope that several products with different total amount can be generated in sequence one by one. For Example, there are 50 Product A, 40 Product B and 30 Product C at Source WE. They schould be generated in sequence. First 50 Product A,1,2,3...50 one by one generated. Then 40B, generated one by one and finally C. At present, I can only achieve one-time generation of all A, then all B and All C. The second Problem ist: there are may be 10 Vehicles in the System. I want to record the total time of the car loaded and empty travel time, and the corresponding percentage of these two items. I would be very very grateful if you could help. I'm really in a hurry and hope to get your help.

People often want to model two or more vehicles or entities moving together. There are a few components to this: 1) Seizing the resource appropriately - can be done in processes, but often best done within the vehicle object to make the modeling easier. Here, a vehicle has 4 properties added to support use of an operator. 2) Animating them moving together - the picture below shows use of a second queue animated on the custom vehicle. 3) In some cases, you also need the "driver" to be shown moving. The Attached Animation Speed illustrated below, accomplishes that. I have attached a model that uses a custom vehicle object to model a wheelchair which is "driven" (pushed) by a person to pick up a patient. *********** FOR VERSION 190 AND EARLIER ************************************* VehicleWithDriver.spfx You could use the same approch, possibly with just animation changes, to model something like a truck or forklift that requires a driver. In fact, I just added a second model to that same project that illustrates use in manufacturing (e.g. a lift truck and driver).VehicleWithDriver.spfx VehicleWithDriver.spfx *********************************************************************************** ************** FOR VERSION 191 AND LATER *********************************** VehicleX3.spfx VehicleWithDriver_VehicleX3_Examples.spfx For more information on the update, see the post below. ***********************************************************************************

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

I've hunted through the forums and online and cannot seem to find a fix for my simple application. I have 1 worker operating multiple work centers (Simio server). He should finish all work at one "server" before moving on to the next server. Otherwise, his utilization goes down substantially due to him bouncing back and forth between the servers and walking all day. I.e. Server A: Parts in Que: 1,2,3,4,5,6 Server B: Parts in Que 1,2,3,4,5,6 Worker is doing A1, B1, A2, B2, A3, B3, A4, B4, A5, B5, A6, B6 with a walking time inbetween each part. I want worker to do A1, A2, A3, A4, A5, A6, walk, B1, B2, B3, B4, B5, B6 I would prefer not to use constraint logic due to the complexity. I've read that somehow the solution seems to lie in setting the Secondary Resources "Repeat Group" status to false and attempting to use the "keep reservation" function, however I have not had any luck. I set the "keep reservation if" function to "ServerA.InputBuffer.Contents.NumberWaiting > 0" which in theory should fix the problem, however my worker continues running back and forth. Any help would be appreciated. Thanks, Jon

Hello every body. I am a beginner on SImio and this software is very powerfull. I have a problem I want to modify Fixed route vehicle's destination. I don't want a vehicle on demand.I need a fixed route vehicle. But I need to modify the vehicle's destination. Because I want the first vehicle Go to the first source and i want the second vehicle go to the second sources. And I have 80 vehicle and i want this loop destination for all vehicle. It's works very well for the First 5 vehicles ( For Source_Aub_Char in my model) and it's doesn't work for the sixth and after it's works. But my method doesn't work for all vehicle. I don't understand why. My method is : - I select the current vehicle with "Path1.Contents.FirstItem" - And After with "set Row" i selected différent sequences table for the current vehicle - I do a count for the number vehicle entrance and the model choice the good sequence table with this counter. There is my simplify model in attachement. Some body can help me to see what's wrong or to give me a better method ? Thank you very much. And sorry for my english i'm french. Question FOrum.spfx

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 model! It took a long time to get the sprint release but now I can see it and it helps. Now I have another problem. I am trying to do a pick up at two different places and the drop off at one destination. There I want to have the transport costs split on the entity with the calculation TransportCostRate/TransportQty. The logic works like this: The transport from Source1 to Source2 (or BasicNode4) should be charged and assigned to ModelEntity.Cost. Then from Source2 to Server1 another calculation should be done, now with the increased transport quantity in dependency. But in BasicNode4 the process is not triggered by the ModelEntity, but by the Transporter. Is there any way that the process is triggered by the passenger? (the entity in the ridestation). The model is in the appendix. Best regards. Model_421.spfx

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

Hello Gosia, I recommend using two State Variables to record the start and end times using the function TimeNow upon the Vehicle’s arrival to a Node. A Decide step is needed to check if the Current Node is different from the Destination Node and that is when values of the State Variables are assigned using the Assign step. The Processes will be set at the Vehicle’s Add-On Process Triggers On Entered Node and On Exiting Node. You can visit the SimBit section under the Support ribbon and check the SimBit titled “Record Distance Traveled” to see a similar example. Another approach is to create a custom Vehicle Class and use a Level State Variable instead of the two Real State Variables to collect information of the travel time. I suggest exploring the Level State Variable in the Help pages under the chapter titled “States”. I recommend checking the SimBit titled “Using Level States (from project Infection Propagation Using Continuous And Flow)” as well. Best Regards, Khaled

Hi! Yes, there is a way. What you could do is use a String.Format expression. This way you can show multiple variables on the dynamic text. On your case something like: String.Format("{0}: {1} {2}{3}: {4}", "Material Costs", MyModelEntity.MaterialCosts, String.NewLine, "ProductionCosts", MyModelEntity.ProductionCosts) should work. As a plus, you could use a state to disable/enable these labels with a button and a process. Something like: Math.If(EnableTxT, String.Format("{0}: {1} {2}{3}: {4}", "State1", ModelEntity.State1, String.NewLine, "State2", ModelEntity.State2), "")

Hi, I have 6 entities arriving at exactly 8am each day. Each of the 6 entities will create a certain number of entities on arrival from their respective distributions. How do I model in my source? I cannot have multiple sources as each entity has its own server processing times. Please can you help? Thank you

Hello, In my model, I have two vehicle types. The first type, MyVehicle, is a subclassed vehicle similar to the vehicles in the SimBit Electric Vehicle, except they use Free Space Only. The other type of vehicles are standard vehicles. My problem is when entities seize a vehicle for transport from one server, I want them to seize the closest MyVehicle and only seize a standard vehicle if no MyVehicles are available. The output node at each server is set to select from the transport list which includes both vehicle types. If I set the reservation method to "Reserve Closest" the closest vehicle of either type is reserved and if I set the reservation method to "Reserve Best", MyVehicle[1] will be attempted to be seized even if it is not the closest MyVehicle. I assume there is a way to use an add-on process to control which vehicle is seized, but I am unsure. Just FYI, I have MyVehicles starting at two different HomeNodes, 5 per node. Any thoughts would be greatly appreciated!! Thank you! Please let me know if this description is not clear.

Hi, I have a series of shipping containers that are fed by a single conveyor, and I want all the containers to fill to a specific capacity whilst minimising the total time to fill. That means that if a container downstream is busy transfering-in an entity, then subsequent entities should stop at an upstream container to mitigate any queing, whilst respecting the capacity limits. At the moment I have the containers represented by sinks, but this doesn't allow me to set capacity limits. I'm using a TransferNode to set each entity's destination with a sequence table, but this doesn't reflect that an entity's destination might change enroute if it's desitation becomes busy or full as it transits. Can anyone please offer some advice or point me towards a SimBit that does something similar? Thanks, Craig

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

I have a multiple combiners into which a single worker provides entities. While the worker is at a specific combiner, I want to check if that combiner's output buffer is full. I'd prefer not to create a separate process for each combiner as I have dozens. How do I code the process so that it is generic and that 1 process can work for any combiner? I'm hoping this is an easy question. Sorry if it's obvious. Thanks for your help.