Here's a line-by-line explanation of the terms:
Line 1: reactionless drive: objective of research to develop
an apparatus, such as a gyroscope, which is capable of producing unidirectional
thrust without the equal and opposite reaction mentioned in Newton’s Third Law.
Line 2: Artificial photosynthesis is one of the next generation of
renewable energy technologies referred to in Lake Water Storage Haiku.
Line 3: Microrobotics or microbotics is the study of mobile
robots less than 1 mm in diameter.
So far I have no explanation for the haiku as a whole.
