Advertising and selling a feature that you don't have sure seems like fraud to me. If it's "the feature is nearly ready but just needs some polish" there's an

Advertising and selling a feature that you don't have sure seems like fraud to me. If it's "the feature is nearly ready but just needs some polish" there's an argument to be made that maybe you were just being a bit too hopeful. But "years and lots of fundamental research away, and we're not even sure what sensor systems were going to rely on", that's just fraud. You're looking for early stage investors, not customer preorders, at that point.