The first sentence essentially says that the quality itself will be using robots to improve [itself].
The second sentence does not specify who is going to use robots to improve the quality, only that their use can affect the improvement in quality.
Generally speaking, since quality is a passive trait, it can't invoke help of other things or processes. We do say "the quality has improved" but that does not make quality active, just indicates a change of state.
Given the above, I think the second is closer to correct semantically (rather than grammatically), and I suppose you've asked it in that sense.
Also, as an afterthought, robots
don't really improve quality directly
, and that's why I'd probably say "through
using robots" or "via
using robots" instead of "by
", although it's only a shade of a difference.
RE latest edit: The "quality" is the subject in both sentences.