topic Re: Item trace Gantt only for some stations? in FlexSim Forum

Item trace Gantt only for some stations?

m_rosadini — Tue, 18 Jul 2017 01:19:42 GMT

[ FlexSim 17.1.3 ]

Hi,

I'm trying to trace the time spent by items on certain stations with a Gantt chart. On the attached model, objects have a label called "gantt" and I would like to trace ony the ones with a label value of 1.

I have set the option in the trace requirements, and it does skip the first object (with a vaue of 0) however, after starting the trace, it doesn't take this into account anymore.

Is this the correct way to implement this? Or someone could suggest a workaround?

I have tried a custom Gantt with the Table presets, however, the actual process would involve around 10 stations and I'm not sure how to make it that after creating an item it should add another entry to the Gantt and write and read another set of rows

Thanks!

support.fsm

Re: Item trace Gantt only for some stations?

matt_long — Tue, 18 Jul 2017 14:35:16 GMT

The Item Trace Gantt Chart was designed with this functionality in mind. Once you start tracing a flowitem it continues the trace until the flowitem is destroyed.

We can manually create the data and display it in a Custom Gantt Chart. I've attached a sample model showing how to do this. You'll have to manually add entries for each item to the table Item Trace that the Custom Gantt Chart will read. I also created a second table, Traced Items, which gives you a single entry for each item you are tracing. The table caches off the rows in the Item Trace table that are associated with that item. The chart can then loop through the Traced Items table and pull the correct data from the Item Trace table.

To expand this to the 10 objects you referred to, just copy the code from Processor2 to additional objects. You won't need to change the code, it will work for as many objects as you need.

Processor1 does have slightly different code because it has to add the initial entry for the item into the Traced Items table. Whereas Processor2 only updates the row from the Traced Items table.

customitemtrace.fsm

Re: Item trace Gantt only for some stations?

m_rosadini — Wed, 19 Jul 2017 19:15:59 GMT

Thank you @Matt Long for the detailed and flexible answer, it was a bit more tricky than I expected!

Re: Item trace Gantt only for some stations?

m_rosadini — Tue, 29 Aug 2017 15:45:25 GMT

Hi @Matt Long a few weeks ago you helped me creating this custom Gantt for one of our customers. However we are facing an issue. The Gantt keeps growing every time an item enters the process and it starts to get very big, making it very difficult trace each item. They are requesting us if it would be possible to group or sort the items in the charts.captura.png

The names of the zones are marked as ATSI1, ATSI2 etc. The idea would be that when a new item enters the chart it gets positioned after the last one of its group. In this screenshot, item 3 should had been placed before Item 2 and so on. It may not seem relevant here but sometimes a new item enters the chart way later in the simulation and it is hard to correlate it with it's group. ¿Maybe with the stats collector could be done? @jordan.johnson

Re: Item trace Gantt only for some stations?

JordanLJohnson — Tue, 29 Aug 2017 16:47:11 GMT

@marcello.rosadini It will be easier/better if you post this as a new question; you can always link back to this question in the new one. In brief, yes, the stats collector and calculated table can do this. I'll watch for your new question, and post my answer there.

Re: Item trace Gantt only for some stations?

JordanLJohnson — Tue, 29 Aug 2017 16:49:24 GMT

Also, how are zones defined? Are they process flow zones? Is each zone a visual tool, with related objects defined? Let me know in your new question.

Re: Item trace Gantt only for some stations?

kevin.megee — Tue, 29 Aug 2017 20:28:41 GMT

@Matt Long how would I track the item time from processor 1, all the way to the sink, or a finishing queue? I would like to see how long an item takes to go through my model from a certain point, to the finishing queue.

Re: Item trace Gantt only for some stations?

matt_long — Tue, 29 Aug 2017 20:34:36 GMT

This is why the Item Trace Gantt Chart is nice because it will automatically trace the item all the way through the model. To do this manually it might be easiest to use Process Flow. You could use a Wait for Event activity to add a listener to the flow item's On Entering and On Exiting. Each time the event fires, update whatever data you need and then send the token back to the Wait for Event to listen for it to enter the next object.

Re: Item trace Gantt only for some stations?

kevin.megee — Tue, 29 Aug 2017 20:46:18 GMT

Thanks for the quick response. I guess I'm confused by your answer. I used the trigger codes from the above sample you created. Is there a trigger "on entry" code that could track the End Time of a flow item from the Item Trace table?7632-customitemtrace.fsm

Re: Item trace Gantt only for some stations?

matt_long — Tue, 29 Aug 2017 21:09:40 GMT

If you're just looking for the total time between two objects, just save off the start time as a label on the item, then when the item reaches the end point you can get the total time using

time() - item.StartTime

Process Flow also makes it easy to track staytimes over multiple objects using an Event-Triggered Source and a Wait for Event together. Then you graph those staytimes by pinning the staytime of the Wait for Event.