[2.1.9] "Set Requests" circuit setting on space platform breaks mixed rocket launches

[yurylink]

Factorio Version: 2.1.9
Modded: No

I started a new game to fully utilise the platform-to-platform item exchange and automated mixed rocket launches. My strategy was to build a "Space Storage Hub" platform to buffer items while transport ships travel between planets. This reduces ship waiting times and acts like a "buffer chest in space," which is crucial early-game when rocket silos are limited (and I believe that was the whole point of mixed rocket lauch).

To achieve this dynamically, I use a constant combinator on Nauvis matching my ship's logistic group, compare it via circuit network against the Space Storage Hub's current inventory, and feed the remaining demand directly into the Space Storage Hub's hub using the "Set requests" circuit option. I was kind of forced to use a circuit network in this situation because the logistics group determines where we are importing from, and I set up all imports from platforms instead of the planet. This way, if I change my ship's needs mid-flight, the Space Storage Hub automatically requests the missing items from the planet and has them ready in orbit for a quick transfer when the ship arrives.

What did you do?
1. I set up the dynamic circuit network described above to automatically set requests on my "Space Storage Hub" platform. Green to read the content and Red to set the requests.
2. I create the logistic group on the ship and let it run for a bit to fill up the Space Storage Hub.
3. I've started to use the ship, requesting small quantities instead of whole stacks
4. Observe how Space Storage Hub will behave.

What happened?
The rocket silos on the planet's surface entirely refuse to launch mixed rockets. The silos don't even see the request from the platform; they only see requests from the platform when there is enough for one full rocket. Essentially, the silos behave exactly as they did before the 2.0 space platform updates: a silo will only activate and launch if the circuit-requested item quantity is large enough to fill a whole, single-item rocket.

By dynamically setting the platform requests via the circuit network, the automated mixed rocket launch mechanic is completely broken/bypassed.

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No requests

But when I change the quantity of train wagons on the logistic group to a big number

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07-10-2026, 05-02-20.png (120.64 KiB) Viewed 544 times

(Initially, I suspected this was blocked by unfulfilled construction requests on a separate ship, but upon deeper testing of this setup, the root cause is that using the circuit network to "Set requests" entirely halts the mixed-cargo logic engine from compiling a mixed rocket. I think)

What did you expect to happen instead?
I expected that setting requests dynamically via a circuit network on a space platform would behave exactly like setting requests manually via the UI. The rocket silos should recognize the multiple distinct item requests and automatically bundle them together into a single mixed rocket launch to efficiently fulfil the platform's demands.

Does it always happen?
Always. Whenever platform requests are driven by the "Set requests" circuit signal, mixed rocket logic fails to trigger, and rockets only launch when a single item can completely fill the cargo bay. Ive even tested several time by increasing the logistic group request of some items to a number bigger then a stack, and when I do that, Rocket Silos send that Item and stops again

I have a strong suspicion that this is related to the fact that circuit network request are hardcoded to import from anywhere but since we cannot chance the import setting from circuit network, I cannot test this

[Genhis]

Hello, I don't see any issues with the save file, all items requested by circuit network were delivered. Can you point me to a place I should look at and give exact steps I should follow?

[yurylink]

Hello, I don't see any issues with the save file, all items requested by circuit network were delivered. Can you point me to a place I should look at and give exact steps I should follow?

Absolutely, Thanks for the quick response.

There is a Radar, a constant combinator and an Arithmetic combinator around the coordinates 92.000 x 422.700. They control the "Space Storage - Navius" platform. The Constant combinator has a logistic group with several items; the arithmetical combinator subtracts what is already present on the platform, and the result of that is sent back to the Radar (and then picked up by the platform to use in "set request").

If you look up the result of that arithmetic calculator (or in the platform itself), there are several items being requested, but none of the items' quantities are big enough to fill up a rocket with one item, as a result, the rocket silos are not sending anything. However, there are enough item requests to fill several rockets with mixed loads of them.

Now, how to reproduce the issue:
Just change any item quantity in the constant combinator to larger numbers (enough to fill a rocket with that item only). Then the rockets will pick that request and send it to the platform.

What I believe the issue is:
The rocket silos don't recognise the capability of sending mixed load rockets when the platform is requesting through a circuit network; they only operate that way when we explicitly set up a logistic group in the platform (through the platform interface, without a circuit network).

[Genhis]

I still don't see any problems with the behavior. I think there is some confusion about orbital logistics, so let me point out a few things:

1. Platform "Space Storage - Nauvis" uses circuit network to request items. At the moment all requested items are delivered. Your arithmetic combinator takes "Terraforming Plannet Request" group and subtracts it from platform inventory content. For example, you want 50 steel chests and platform already has 37, so the combinator outputs 13. This gets fed back to platform requests which now see that you only want 13 steel chests. You have 37, so the request is satisfied.
2. Platform "Transport Ship" has all its requests set as "import from platforms only". Rocket silo in "Read orbital requests" mode includes such requests. This is what you see on your red wire which isn't attached to any logic. Maybe it shouldn't do that?
3. Platform "Transport Ship" can't import its requests because they are also requested by "Space Storage - Nauvis".

Mixed rockets don't differentiate between normal requests and circuit network requests - it is all one big group from this point of view.

[yurylink]

Well, after some digging, you were right, is missunderstanding of the circuit network.

The whole reason that I set up artitimetric was set up in the first place was because I noticed that sometimes rockets send a few more itens that it needs when mixing them. But fundamentally, I should use the decider combinator to clear up fulfilled requests and thus allow the platform to send items to other platforms and just ignore a few more items being sent.