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I have 2 transports delivering entities to 3 servers. What should be happening is that Transport 1 loads entities to capacity (12) then moves to Server 1 and delivers all of the entities (12). Transport 2 should load 12 entities and deliver all 12 to Server 2. Transport 1 returns to Home Node and loads 12 more entities for delivery to Server 3... and so on. However, what is happening is that both Transports are loading 12 entities then moving to Server 1 and delivering 4 entities each, then on to Server 2 and repeat and so on. I have removed and added servers to confirm that for some reason the Transports are delivering 1/#ofServers of their total capacity, conducting all of their deliveries and then returning to home once empty. I have limited the timepath to each Server to only allow 1 Transport at a time, but then Transport 2 just waits at the Home Node until Transport 1 is on its way to Server 2. Then it moves to Server 1 and just ends up one node behind Transport 1 at all times. The dispatch logic: (Server1.InputBuffer.Contents.NumberWaiting <= 12)||(Server2.InputBuffer.Contents.NumberWaiting <= 12)||(Server3.InputBuffer.Contents.NumberWaiting <= 12); set at Smallest Value for Selection Goal; Selects from a List of all Server Nodes.

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

I'm trying to model a towing company. A call comes either jump start or tow (entity 1 and 2) from two different sources. They go through a dispatch (server1) and get delivered to a specific driver (servers 2,3,4 or 5) . Each call coming in will have some exponentially distributed distance from origin associated with it (and direction component?) My challenges are: Is there a way to take and entity from a source and move it into free space some vector away from the source (distance and direction). Then, if that is possible, can I move a server to that location to process it (and if a tow then move some other vector distance after process). Finally, the ultimate goal of the model is to create a conditional routing logic for the dispatch server to compare distance from call and availability of drivers. Such that if a driver is finishing up near the next call, that server will take priority over the one with an empty queue if further away. TLDR: Can servers move? Is there a way I can change how long a path is based on variable input?

I have created two real states for each entity and depending on the probability based, assigned to each entity a different processing time. I guess that this should work, but now I realized that I have another problem. Before the two servers that I mentioned in the post, I have another server with a lower processing time. It is supposed that Server 2 and Server 1, that have a larger processing time, should create a bottleneck, and I want that all the queue stays in the input buffer of that Server (let's say Server 0). The problem is that the entities that finishes at Server 0, go directly to the server 1, although I specified that the output buffer of the Server 0 is 0, the path capacity is 1, and the input buffer of Server 1 is 0. I even can appreciate how some entities that arrive to the Server 0, if this server is busy, skips that server and pass directly to the next one. How it is possible? I want to create the queue in the Server 0, and then move to the other ones when they are empty, always following a FIFO rule. Thank you so much.

Hello, I am simulating a restaurant queue with two servers. The queue is lineal and the entity order is FIFO. The 85% of the entities goes to Server 1 and 15% to Server 2. But I need that all the entities do the same path. So, those entities that have to go to Server 2, wait till Server 1 (capacity==2) is empty, and then go to Server 2 (capacity==2) without processing in S1, and those entities that go to Server 1, then, wait till Server 2 is empty, to move on without process in Server 2. The real example is a lineal queue where you have to choose between two foods, but independently which one you choose, you do the same line, taking the food in the server you choose and waiting for the people that is in the other server to finish in order to move on and pay. How can I do it? Thank you so much.

I am trying to simulate a model of a factory where 6 hours of planned maintenance occurs every Wednesday at the same time, from 8am to 2pm on the production line. There is a second almost duplicate line which can then be operated when the maintenance begins, it is attached to the 1st line after the source and the first server. The factory is 24/7 in production. When this occurs the 1st line should clear of all entities and should remain empty for the 6 hours. How is it possible to simulate this 6 hours of no production on the first line after the first server and when this happens the source should continue producing but follow another path to a second line after the first server. From this experiment i want to see how many entities can still be created over a period of time when the maintenance occurs by using the second line.

I'm pretty sure my whole approach is flawed, but I don't see how else to do this. The attached is a very simplified version of what I'm trying to do. In the real problem, I have empty containers that enter a detached queue based on when they are retrieved from customers. I also have workers that need to select (through a fairly complicated process) which of these containers to batch together to enter a filling station. This selection process is complicated because it depends on filling material, pressure, volume, and safety stock of the sku (multiple skus can be combined in same batch provided filling material, pressure, and volume of container match). Anyway, what I'm aiming for is Create a batch When the worker is idle, he will go to a node and search among empty containers in the detached queue to assemble a complete batch. If there aren't enough containers, the worker will wait, idle. As empty containers arrive at the detached queue, they should trigger, somehow, the worker to try to create a batch again. There are new containers now, so maybe a batch is possible. (Preferably, since hundreds of containers could arrive at a time, this trigger would be for all the containers arriving at this specific time, not each container doing a separate trigger.) With the batch, the worker should move to a server, seize it and wait while the containers are filled. Then move to a separator to separate out the batch, moving the containers to full inventory and the worker should go back to try to create another batch. I'm stuck in a couple of places, specifically (so far) . . . I can't seem to get the worker, once batched, to move to the filling station. In fact, the Move block in PickingStation_Entered doesn't even fire. I can't figure out how to get the entity to trigger the worker to reevaluate the batching process. However I try this, the batching process is executed by either the entity's token or a model token. I can't see how to get the worker to be the executing token. Any help or guidance would be appreciated. Model.spfx

Hi, Is it possible to access the filter expression of standard Dynamic Selection Rules for use in processes? Basically I want to filter queues based on some Entity properties, eg, being a specific material. However standard dispatching rules only apply the filter if multiple entities are in the queue. Eg, if a an entity of "wrong" type arrives to the InputBuffer of a Server and the input buffer is empty it will seize the queue anyway. In my case I want to keep the server starved until an entity of correct type arrives. I found a way to implement that by filtering the queue with the same expression as used in the dynamic selection rule, however I need to add another property for that expression, which is a bit confusing. Thanks for your help Michael

Hello, I'm modeling an orange factory. One thing that I'm trying to solve is the modeling of the reception pools (of oranges). 1) Arrive trucks. 2) The truck is weight. Every truck have a random value of kilograms of oranges. (integer) 3) The truck dispose the oranges in a workstation. (workstation = reception pool). This is model with a Separator. 3.1) There are 3 workstation. 3.2) Every workstation has diferent Input Buffers. 3.3) The entity once entered in MemberOut@Separator1, it triggers a decide process. 3.3.1) This decide is to choose the workstation depending of the Quantity of Oranges versus the Input Buffer. Now I need to Wait until the Input Buffer is Empty, but I'm having problems with that, because the entities don't release from this server. If there are doubts about the model or anything else, I will answer as fast as possible. test1.spfx

Hello! I'm having problems with ExcelWrite process. I have a few months in Simio and I didn't have this problem before. I need to write the "TestTime" of every entity in the system after the first test (server). 1) I created an Excel Document. 2) I created and excel connection. 3) I linked the excel connection with my excel document. 4) I made a process. 4.1) I made an assign, where an "i" integer variable take the value "i+1" so i can write all the data in different rows. 4.2) I added the ExcelWrite process to write the data that I need. This data is "i" and "TestTime" 5) I used the add-on process triggers to use the process (4 step) 6) I ran the model. 7) I went to my Excel Document and It was empty I will attach my model, so you can see what I'm doing wrong. P.S. : I have Microsoft Excel 2010 ExcelWriteTest.spfx

Hi farnaz, in fact, you should be checking your buffer at the beginning of the period 10-11. If all machines stop at 10, entities will stop flowing shortly after. Therefore you could check around 10:05 or somewhere around the beginning of the period. To do so, you can use a timer (Definitions>Elements>Timer) and set it to occur every 24h with an offset of 20h05m (10:05PM)). Then, have a process being triggered by that timer. In that process you would check if the input buffer was empty or not (Server.InputBuffer.Contents==0). You can do that using a Decide step. If the condition is false (there is something in the buffer) change the resource state + Capacity of the server so that it processes said entity. For it to work for another hour you could set another timer or use a paralell process with a delay of 55min. At the end of that time you would turn off the server again. Hope this helps (I haven't tested it to be sure it works)

HELLO, before asking my question ı want to make some explanations about the model. 1- the model is source- server 1, server2 - sink. server1 and server2 has no connection. source connceted with this two servers and two servers linked to the sink. each server has different processing times. 2- server1 is required 5 minutes in every 10 hours while server2 is required 6 minutes in every 8 hours. server1 cannot give service during the maintenance and maintenance cannot start if there are customers in queue. 3- when either server finishe serving a customer, server takes the next customer from the server's queue, if any, and if server's queue is empty but the other is not, server takes the first customer from the other queue. My question is how to build this model? could you please help me???

Hello. I'm completely new to Simio, but I know it has a lot of potential. I was wondering if there is a way to make a workstation work on multiple entities simultaneously. (Much like the 'initial capacity' of a server) I have tried to work a little with the 'Operation Quantity' and 'Processing Batch Size', but they don't quite fulfill what I try to do. I have 8 different entity types that spawn from a Source. I would like the Workstation to be able to work on 28 entities simultaneously, such that, if 28 entities entered the workstation queue at once, all 28 leave the workstation at the same time (if the workstation is empty, of course). But if 14 are already in the workstation and another 14 arrive at the same time, they would still be processed simultaneously, but the 14 that are already in the workstation being processed of course are processed quicker than the rest, as they've been in the workstation a set amount of time. I hope this is possible, and thanks in advance. EDIT: I just decided to go with a server instead, which made it a whole lot simpler. Thanks for the help.

To acess a state variable of an entity that is being processed at a server (let's call it Server1) you should type the following into the label, assuming there is only a single entity at the server: Server1.Processing.Contents.FirstItem.ModelEntity.Name Mind that you will get a warning if you run with such expression in a label, because you will be at times trying to reference an entity at an empty station. Then, you should expand the expression to: Math.if(Server1.Processing.Contents.NumberWaiting != 0, Server1.Processing.Contents.FirstItem.ModelEntity.Name, "")

Love the articulated robot! Is there a way to specify which direction it rotates? On my initial trial it only moved clockwise when loaded and counter-clockwise when empty. In the model I have the robot loading a server and then unloading it. I figured the travel direction was because of where I located the nodes. I moved the output node of the server so that it would be less distance to go CCW but it still ran CW. I continued moving things around until I made it work. It seems to be tied to where the node is located left/right (or east/west) of the robot's base node? It's not a big deal for me right now, but I figured it might come up if I try to send a robot through a wall or something

This is my first time using this forum so I hope I am posting this in the correct section. I am currently busy with a problem involving the dust suppression program at an open pit mine. In open pit mines water trucks are used to maintain the condition of haul roads and reduce mine dust. Water trucks load water from refilling stations and traverse the road to spray water. After the water is exhausted, the water truck travels toward one of water stations for refilling and then continues to traverse the roads to satisfy the watering patterns. The water trucks run 24 hours per day.In practice the watering frequency of each road is related to the traffic intensity of haul trucks. The period of effectiveness, after the road has been watered, can range from 30 minutes to 3 hours. Regular light watering at approximately 0.3-0.5l/m2 is much more effective than infrequent heavy watering. To simplify the problem each road will be assigned a watering frequency (e.g. every 60 minutes) and a sliding time window (e.g. 10 minutes). The water can therefore be sprayed on the road within the given time window (e.g. 50 to 70 minutes). If the trucks service the road more frequently than every 50 minutes the road will be over watered and this can cause a host of problems. If the trucks water the road less frequently than every 70 minutes dust aggregation will start becoming problematic. In order to satisfy the water demand of the roads, it is possible that a truck waters a road segment first, then travels along the next road segment without watering it, and then waters another road segment. The road segment that a water truck traverses without watering is called a dead heading. A bidirectional road has to be watered in each of the two directions Empty water trucks are refilled at the refilling stations. A refilling station can serve a limited number of trucks at the same time. Also, a limited number of trucks can wait before being refilled. Hence, every refilling station has two kinds of capacities: the capacity for refilling the trucks and the capacity for holding trucks. If a refilling station is overloaded, some trucks need to be reassigned to a different refilling station. My main problem at this stage is how to model the dust aggregation on the haul roads. I started by setting up each road as a source server sink and then only displaying the server queue. The entities can then be modeled as dust clouds. The trucks then tend to the servers as operators. This still does not give the desired outcomes. I’m struggling to schedule the trucks to move on the shortest route and then return to the nearest filling station once they have depleted their water supply. Does anyone have any other ideas on how to approach the problem? Thanks for your help! Regards Carl-Gustaf Gericke