It seems to me that it doesn't really work that way. You're not a cog, and robotics capabilities research is hugely multidisciplinary, so you should be able to synthesize unique insights of your own. There are always, always open problems and issues that nobody else is looking at, even in crowded fields.

Besides, as a noob researcher, you'd mostly be doing somebody else's grunt work, at least for a while. Learning the ropes. Then, if you survive, you'd be able to devote substantial time to projects of personal interest -- and those might be high-impact, or at least appear that way to you.