[He doesn't answer straight away, debating whether to let Peter just work it out for himself. But it wasn't a very clear picture right now and he knew it, so he does reply.]

Robotic legs.

I was trying to get them to walk on their own. One step at a time. Literally and figuratively.

I am working on creating an A.I.

I... should have put together more of their body. Vision, especially, so they could navigate by sight but I... became impatient for results. I think I overloaded the system.

[Now he sounds regretful.]