I have an application that receives a number of datums that characterize spatial / temporal processes. It then filters these datums and creates actions which are then sent to processes that perform the actions. Rinse and repeat.

At present, I have a collection of custom filters that perform a lot of complicated spatial/temporal calculations.

Many times as I discuss my system to individuals in my company, they ask if I'm using a rules engine.

I have yet to find a rules engine that is able to reason well temporally and spatially. (Things like When are two entities ever close? Is entity A ever in region B? If entity C is near entity D but oriented backwards relative to C then perform action D.)

I have looked at Drools, Cyc, Jess in the past (say 3-4 years ago). It's time to re-examine the state of the art. Any suggestions? Any standards that you know of that support this kind of reasoning? Any defacto standards? Any applications?

Thanks!