ich habe ein paar Fragen. Das System, das ich skizziert im Anhang beigefügt habe, macht mir Schwierigkeiten. Ein Fördergut ("Kabine") soll nach einer Förderstrecke in durch eine MFsteuerung auf zwei halbkreisförmige Förderstrecken aufgeteilt werden, danach über eine weitere wieder zusammengeführt werden. Folgende zwei Methoden wurden eingefügt:
if Eingang.inhalt.leer then
Nun meine Fragen:
1. Warum werden keine Kabinen ins System eingeführt? Wenn ich eine Simulation starte, passiert gar nichts. Die Methode "erzeugen" ist bei der Station "Eingang" unter Steuerung "Ausgang" hinterlegt.
2. Was bedeutet die Fehlermeldung, die ich im Anhang beigefügt habe und die erst seit einfügen der Materialflusssteuerung auftaucht?
3. Die Materiaflusssteuerung soll sicherstellen, dass die Kabinen abwechselnd auf dem äußeren und dem inneren Kurvenband transportiert werden sollen. Gibt es dafür noch andere Lösungsmöglichkeiten, um die Fehlermeldung zu umgehen?
Mit freundlichen Grüßen,
Insbesondere stört, dass die Materialflusssteuerung anscheinend selbst Zeit benötigt. Sie könnte das Fördergut schon längst auf die äußere Schleife umsetzen, dennoch wird das Fördergut vor der Materialflusssteuerung rot angezeigt. Deshalb gibts einen Stau, obwohl der nicht auftreten dürfte, da die Taktzeitein groß genug dimensioniert sind.
For some reason you get a critical error. Please upload your model so that the Siemens people can take a look at the underlying issue.
Now, your model: keep it simple. You can use a simple cyclice exit strategy (default) and set blocking to active. Instead of methods you can use a simple source object (instead of your object Eingang).
thank you for your advice. I changed the method and the station to a single source, now I don't have this error any more.
But I have another question. I show you my model at 6 different instants of time and my material flow control. I calculated the cycle and the distance between two objects, so there shouln't be any waiting pieces. But unfortunately, there are. And then, the distance between two objects change unwantedly. Why does that happen? Does the material flow control need the time? It's intendet to just put the objects on the free curved conveyor without and waiting processes. Additionally, the ropebelt conveyor before the curve shouldn't change its velocity! And I didn't add a buffer there!
Thank you for your help!
All the best,
would it be possible to post your model?
We would like to find the reason for the critical error you get.
Please can you post the original model or at least tell which version you ar using?
It is impossible to locate the problem without knowing the settings. The FlowControl object does not take any simulation time. You can apply many settings to the length-objects to make them work as you desire, but the most important ones are speed of the Line object and the length of the MUs.
Sure. I added u the model, but it's not the original one with the error. The error was caused by a single station and a method, but I don't remember what I did there. I started yesterday with modelling a pre-model and only saved the actual version, it will get more complicated in February.
I found out that I calculated wrongly. The object was too long, resulting in a queue before the curve. I adjusted the velocity of the curves conveyors, so that problem is already solved. After the curve (and an irregular interval on the following conveyor) I need a mechanism clocking the obects in a time distance of 12 second (later 8 seconds) again. Therefore I wanted to implement a single station which should wait, containing one object, until the following arrives at the conveyor before. The conveyor needs 12 (or 8) seconds. But with my method the station just pauses and the whole system crashes. It should be a very simple method, shoulnd't it?
if Regelstrecke.leer then
Haltestelle.pause := true
else Haltestelle.pause := false;
Sorry for relocating the problems a lot!
All the best,
The reason why it does not work the way you thought about it, is that the method Takten is only triggered once. Once the object is paused, it is not triggered again to unset the pausing.
Some considerations. Personally, I would only use length objects (e.g. Lines), to keep as much physical integrity (so no SingleProc). I would also suggest to switch on vector graphics (tab Graphics of the MU) so that you can see the correct lengths. You can remove the FlowControl objects, since they have no function here, you can apply the same settings to the Line.
There is a simple way to implement time-based gaps between MUs: use the recovery time (tab Times of the Line). It prevents an MU from entering for the given amount of time. If needed you can even use a formula to make this time variable and dependent on the state of some objects (this has worked really well for me).
Finally, I think you do not want the MU to stay waiting all the time. I mean, you want to load the cabin with skiers and once it is full it is good to go, right? I sure hope so, because I always want to be back on the top of the slopes as quickly as possible!
thank you for your quick responses.
I'm going to chance the material flow controls and the single stations to lines as you recommend me.
How does it work exactly with the time management? I know what you mean with recovery time and the formula, but what exactly to I have to put in? I'd like to clock the cabins coming from the curved conveyor, how can I tell the conveyor to move the right distance and then to wait until the next cabin arrives from one of the curved lines?
The model is not about skiing, so we don't have time pressure. More important is to keep or to adjust the time distance between two cabins. Therefore, the clock has to be very precise. This has to happen on the conveyor after the curved conveyor which should regulate the time distance. Do you know what I try to explain ?
All the best,
I modelled my MU in the 3D-mode, Then I got an error pop up and now I can't connect ANY object to my source any more. So I can't run any simulation!!! Thank you for your help!
All the best,
After restarting Plant Simulation it works again, but my 3D-modell ist still gone. It was hard work. Why didn't PlantSimultion connect the 3D with the 2D modell`?