Ball machines exist that allow practicing ground strokes like forehand, backhand, volley and overhead. However there is no  device that assists the player with their serve on the tennis court today.
The challenge for a tennis coach, while watching the student struggle with the toss, is to first get the player to experience hitting a good serve with the correct toss. Coaching time is less productive as the student is tossing the ball incorrectly and thus hitting faulty serves.

This invention called Serve Assist, will toss the ball for the student at the
desired location at the desired instant, so the student can actually hit the
ball and realize for herself the virtue of tossing the ball correctly.  The kinetic and visual memory built by repeatedly hitting the ball at the desired location and instant will be invaluable in finally realizing where to toss the ball, so as to hit a good serve.

The invention also marks the ball with laser to highlight the appropriate point of contact. This is customizable by the coach based on player parameters. This provides instant visual feedback to the student and the coach.

In the second phase of coaching with Serve Assist, the student actually tosses with the machine. In this mode, the student realizes the variation in location and height of the ball toss with respect to Serve Assist. The set of programmable sensors, will toss the ball only if it senses a valid serving hand motion. This will encourage a consistent tossing arm action.

Working with Serve Assist, maximizes the Coaches productivity on court.