is there a way to configure a circuit signal to detect weight?
would be very useful for mixed cargo and remote launches.

I don't think there's currently any way to do that. Launching when a certain weight threshold is met could be a worthwhile feature to add. I don't have a lot of time for mod development these days but it's something I'll keep in mind for the future.

This sounds like a great idea.

@S6X Since you mentioned you're short on time, I may be able to implement it for you since it seems fitting to be in this mod.
If you're open to it, I could do the coding and submit a pull request if you were to upload the source code to a GitHub repository.

Thanks for the offer but I have more time for modding now so I should be able to get to this soon!

Looking forward to your updates!

This has been added!

Nice! Until this got added, I used my own (private) mod to output an additional weight signal from rocket silos, but this seems like a more streamlined approach for a simpler circuit network. Nice work!

I have not played in a few months, great to come back and see this, but I'm having a brain not braining day and cant figure out how to get it to work?

Can set the launch weight but it does nothing and cant find a signal that reads it?

The launch weight does not allow the rocket to launch unless the rocket's weight is equal or greater than the specified weight. If you want the rocket to automatically launch when the weight limit is met, you can set up a constant combinator to send the rocket a launch signal all the time.

I see, thanks!
Also just found this: https://mods.factorio.com/mod/rocket-silo-weight-combinator?from=search seems like a great match too.