Sometimes we overlook the basic building blocks in our field. In this case the four basic stroke types are crucial in understanding the mechanics of how certain rudiments, and hybrid rudiments work. Learning the four basic stroke types can give you a simplified measurement tool for stick heights when executing these rudiments, and ghost notes.
Full Stroke (rebound) Starts high, ends high.
Down Stroke Starts high, ends low.
Tap Stroke Starts low, ends low.
Up Stroke Starts low, ends high.
Practice each of these with a metronome to execute proper timing. Find a mirror to practice these in front of. Try keeping both hands around the same height for each stroke type.