A mixed-reality sport simulation system includes a projectile-tracking sub-system to generate projectile-tracking data when a projectile is launched by a user, a near-eye display to display mixed-reality virtual objects displayed over physical objects within a field of view of a user representing lines of sight of the user, and a controller. The controller may direct the near-eye display to display a mixed-reality environment including virtual objects within the field of view. The near-eye display may provide an unobstructed real-world view for view vectors below a selected pitch angle and at least a portion of the mixed-reality environment for view vectors above a selected pitch angle. The controller may receive projectile-tracking data in real-time from the projectile-tracking sub-system and may direct the near-eye display to display one or more virtual objects representing a trajectory of the projectile within the mixed-reality environment in real-time based on the projectile-tracking data.

A device to function as a training aid designed to improve the tennis serves, ground strokes and volleys, badminton serves and strokes, volley ball serves and returns, baseball batting, racquet ball serves and returns, and squash serves and returns. It is also useful in any activity where the user seeks to improve striking performance when a sports object is suspended in a particular three-dimensional space location.

A tennis swing training apparatus is provided, which is a spherical spacer with a strap with a fastening device to hold the strap on the arms, to prevent the spherical spacer from switching position or falling out during the process of the swing, which when put in between a limb from a body part or strategically placed on the body it separates or holds the arm and swing into position to maintain proper position by having the player squeeze or feel the feedback of the apparatus. The apparatus can be used to help fix most of swings and shots used in tennis including one handed forehand, two-handed backhand, forehand and backhand volley, forehand slice, one-handed backhand slice, overhead, and the serve.

A tennis serve trainer mechanically encourages and causes the execution of a counter-intuitive hitting-up-on-the-ball service swing. The trainer has a straight shaft and a ball which can slide freely on the shaft between a tennis racquet grip on one end and a cap on the other. The ball is magnetically held against the grip until a threshold swing speed releases the ball. The magnetic force, the distance from the grip to the cap and the weight of the ball are coordinated so that the ball will strike the cap at the apex of the swing. At that moment, the arm is fully extended, the racquet head speed is accelerated to its maximum, the angle of attack is ideal, the ball and the racquet meet at the perfect impact point at the apex of the serve, and a snap in the racquet motion happens automatically at the top of the swing.

A training device for tennis provides multiple training stations for various tennis strokes.

A tennis teaching aid comprises a stand and a ball (10) and a guide (12) mounted on the stand for rotation about an axis. The guide (12) extends around the ball (10) and defines a planar guide plane that is parallel to but spaced from a required path of a tennis racquet to hit the ball (10) with topspin. The majority of the ball (10) projects above the guide plane for contact with a tennis racquet so that a correct contact with the ball (10) is achieved when the racquet moves parallel to, but not in contact with, the guide (12) and the ball (10) is spinning about its rotational axis.

A tennis training aid includes a glove and a wrist brace. An attachment mechanism extends between the back side of the glove and the wrist brace. The attachment mechanism has a first piece releasably connected to second piece so as to secure the glove, and thus the hand, at a desired angle relative to the wrist brace, and thus the wrist. The attachment mechanism preferably has an adjustable length so as to select the desired angle. Preferably, the attachment mechanism is a strap clip. The tennis training aid can also include both right-handed and left-handed gloves so as to accommodate for users having different dominant hands and allowing for use of the training device for the serve toss and the forehand and backhand strokes.

A tennis swing training apparatus is provided, which is a spherical spacer with a strap with a fastening device to hold the strap on the arms, to prevent the spherical spacer from switching position or falling out during the process of the swing, which when put in between a limb from a body part or strategically placed on the body it separates or holds the arm and swing into position to maintain proper position by having the player squeeze or feel the feedback of the apparatus. The apparatus can be used to help fix most of swings and shots used in tennis including one handed forehand, two-handed backhand, forehand and backhand volley, forehand slice, one-handed backhand slice, overhead, and the serve.