A ball-throwing machine includes a camera connected to a computer vision unit and a microphone connected to a speech-processing unit. The computer vision unit processes images from the camera to determine a user's position, and to detect user gestures from a predetermined repertoire of gestures. The speech-processing unit recognizes user vocal commands from a predetermined repertoire of commands. A computer receives information from a control panel, from the computer vision unit, from the speech-processing unit, and from a file describing the ballistic properties of the ball to be thrown. The computer accordingly determines a ball trajectory according to the user's position and parameters indicated by a combination of control-panel settings, user gestures, and user vocal commands. The computer then adjusts the direction, elevation, ball speed, and ball spin to conform to the determined trajectory, and initiates throwing of a ball accordingly.