I quit working on this same idea about a year ago after concluding that the resolution on (existing) 9-axis IMUs wasn't good enough for serious tennis players.
Then again, maybe just being able to see your racquet head speed increase as you improve your technique will be enough for a "quantum of utility" for beginners.
Then again, maybe just being able to see your racquet head speed increase as you improve your technique will be enough for a "quantum of utility" for beginners.
Good luck to them!