haptic feedback learning

one of the hardest parts of racket sports is learning proper swing mechanics, for instance golf, tennis, table tennis. You can hire a coach and spend years and lots of money perfecting a swing.

the hard part is some shots have limited feedback, i.e it's hard to FEEL if you're doing it right due to limited resistance, instead you rely on feedback from a coach adjust your swing, then hopefully lock it in and practice practice practice until it's good.

I suggest a two part technology.

First pro's would wear a high resolution motion capture suit, plus accelerometers on their racket, wrist etc to give detailed information about how their perfect strokes move through time.

next the amateur would wear the same rig, plus some cleverly placed gyroscopes and vibrating motors. During the stroke the computer would compare your wrist angle, racket position etc to the pro player. If it saw that you were twisting your wrist too early or late or what not. It would apply resistance on that axis in the form of gyroscopes and vibration.

That way you could FEEL if your stroke is right or wrong. This could be applied to other activities like driving vehicles etc. anywhere you can study a "good movement" then compare the students sloppy movement and try to nudge them back into a better position.

alternatively you could use one of thoses powered exoskeletons but have it apply resistance instead of assistance.