As I offered to RoverDude on reddit I plan on adding on-rails gathering for the particle collector. I just wanted to say "hi" and lay out my plans for the initial work. Basically for the first iteration I plan on simply recording the flow and the timestamp every time the collector gets updated. Then when you return to a vessel I will use the flow and difference in time to inject a single large amount of Karbonite. There's plenty of ways this can get abused by players, but it should be enough to get started on. In the future power consumption and orbit eccentricity should also be taken into account. I'm doing this because the first time I read about Karbonite my immediate thought was "I want to make an unmanned self-resupplying fuel depot in LKO" and this is not possible until on-rails harvesting is implemented.