I want to halt patients (agents) from seizing treatment rooms (resource) from two resource pools until one of the pools has one room available. This because once the patient has seized from one pool, it will be blocked to evaluate seizure from the other. I've tried to use "recalculateResourceChoiceConditions()" to fix this problem.
Now, I tried using a Hold block which in my head should work perfectly as long as the blocking condition is "(TreatmentRooms.idle() + TreatmentRooms1.idle()) == 0 ". This, however, yields a logical error saying that the agent cannot leave the previous block. Is there another block I can use to emulate the wanted logic, or is there something I can do with the Hold block to circumvent this error?
You need a queue ahead of the hold block. "Hold" does not come with its own queue.
Related
in my model I have a queue were multiple agents from different sources come together to seize an transporter ( see picture). But now they leave immediately after they enter the queue to the seize transporter block. But I want to keep them in to queue until a transporter is free and then the first one in the queue should seize a transporter and so should move to the seize transporter block. How should I fix this?
There are several ways:
After the queue, add a RestrictedArea elements to limit the number of agents in the Seize seizeTransporter4 element. In the queue, you can sort the agents.
Instead of a queue element, use a Wait element, in which case you need to write the logic for extracting agents and sending them to seizeTransporter4 element.
The second way is more flexible in terms of writing logic.
seizeTransporter has its own embedded queue. You can access that value with seizeTransporter4.size(). If you insist on having them separately, instead of queue, use delay block, with stopDelay option. Whenever the seizeTransporter4.size() drops below number of available transporters, run the stop delay function. Like
if (seizeTransporter4.size()<=3){
myDelay.stopDelay(myDelay.get(0));
}
I am trying to simulate manufacturing process by using statechart. And i have created agents for particular machines by statecharts and connecting those agents according to manufacturing process with help of resource pool, seize block and release block
My agent is passing through the resource pool and seize block. And I am expecting to run the model one after another seize blocks. However, when I run the model my all three statcharts are active at a same time, which I do not want. can anybody suggest me a possible way to avoid simultaneous process?
I'm assuming your manufacturing processes don't take 0 time. You're missing Delay blocks, causing all your blocks to execute at the same, instantaneous moment.
On a side note, what you're showing us isn't a statechart, but a flowchart.
I am modelling earthmoving operation. Every trench agent seize two transporters, one excavator, and one truck. When truck is released it will do some other job before been seized again by the same trench. So this process repeat until the trench will be empty.
The process is occuring for two three times without any problem but after two three times the trench agent is not go out of the seizeTransporter block (the one that seize truck). I have a delay block after the seizeTransporter block and it use Maximum Capacity. So it should not be a problem and it should not prevent the seizeTransporter block out port to push the trench out.
I noticed this is hapenning when the truck stop to resolve a collision. It looks like the collision cannot be resolved and the truck stay where it is for ever. :))
I have tried so many things that could solve this problem but none of them works.
There is an option in the material-handling library TransporterControl element to override transporter conflicts after some time. Maybe reduce the default timeout of 10 model time units, see below:
I'm a new AnyLogic user so hopefully this is a simple problem. I would like to use a block as to represent a storage area for items to be used in an assembly, I am using the delay block with delay time of 0, but maybe the queue block would be more appropriate? I have set up a model in which every X number of seconds a "truck" arrives and if the delay block contains less than a specified capacity of elements, the inject function is called to refill the block. This sort of works, but is seems that the agents are flowing through the delay block's out port and thus do not count toward its capacity (that makes sense to me...) resulting in my source blocks continuing to create agents when the system isn't ready for them. My delay block is followed by a "move by transporter" block which seems to be getting all of the delay blocks outputs immediately. There are only two transporters in my model and I am not sure why more than two agents can be accepted by the transporter block at a time. I set my transporter fleet to have a capacity of 2 but that did not solve the problem.
Any advice would be helpful! Perhaps a different approach is needed. My goal is to have an essentially unlimited pool of parts at the inlet of the factory, but only create agents when the downstream processes are able to pull them in. Thanks in advance!
Welcome to SOF :)
Best use a "Wait" block here:
Let your trucks dump stuff into "Wait" whenever they arrive. Your downstream block can now pull them when they are ready using myWaitBlock.free(someAgent for as many agents as they want to pull from it.
Similarly, you can use a Delay with infinite capacity and set its type to "Until stopDelay() is called". Then similarly as the "Wait" block, you call myDelayBlock.stopDelay(someAgent) when you want.
Another option: Use a hold-block in front of a normal (infinite) queue and unblock it when ready: myHoldBlock.unBlock(numToLetThrough) --> probably the easiest
PS: Please also check how to ask good questions here on SOF, yours is very long, much easier to understand with some screenshots :) --> https://stackoverflow.com/help/how-to-ask
I'm trying to emulate what QUEST does when a buffer is queried for a certain Part. In there if the part is not in the buffer the request is left pending and if a Part arrives to the buffer it's released to the machine requesting it. I have also seen this behavior in SimPy which is another DES engine.
I can't seem to find a simple way to do this in AL. The queue block has the following methods:
release(agent): Will return false and forget about the request if there's not an agent as the one specified
remove(agent): Will return null if there's no agent in the queue
So those methods won't do what I want...
It gets a little more complicated as the queue contains agents with parameters and I want to request a specific set of parameters (let's say the agents have a number parameter that can go from 1 to 3 and I'm only interested in agents in the queue if this parameter has the value 2).
Also there's a series of agents pulling this agents from the queue simultaneously and I'd like a priority to be set (let's say FIFO)
so there's a couple things that I've tried and have lead me nowhere:
Using a seize block instead of queue and adding the agents to the embedded queue in the seize block. -> I can't find the proper method to seize from the buffer in a different way from a buffer block (so I moved to option 2) but seize does have a promising customize resource choice that could help with the parameter down-selection
Using a seize block and storing the agents in a pool as resources. issues with dynamic creation of resources, seizing the appropriate one etc...
Creating a queue of requests that have returned null from a queue. This sounds like an overkill but I'll look into it
All of those appear to be a bit complex for such a simple thing in other softwares for simulation so I'm wondering if I'm missing something or if someone has come across this issue before
Suggestion 1: may it helps you to store the agents in the queue in a collection (or different collections, according to the parameter settings). Events: "on enter" and "on exit"
Suggestion 2: may the Wait - block helps you here?