A ball striking device, such as a golf club, includes a head with a face having a ball-striking surface configured for striking a ball, a body connected to the face, and at least one channel in the ball-striking surface of the face. The region of highest COR response of the face is directionally enlarged toward the channel. Depending on the size, shape, and location of the channel, the face can be altered to provide greater COR response and increased energy transfer for impacts at specific locations on the face.

A ball striking device, such as a golf club, includes a head with a face having a ball-striking surface configured for striking a ball, a body connected to the face, and at least one channel in the ball-striking surface of the face. The region of highest COR response of the face is directionally enlarged toward the channel. Depending on the size, shape, and location of the channel, the face can be altered to provide greater COR response and increased energy transfer for impacts at specific locations on the face.

A method of selecting a golf club head for a specific user, includes: (a) receiving first data comprising impact location of each of a plurality of golf swings taken by the user using a test golf club; (b) generating an impact probability map specific to the user; (c) providing second data comprising correlations between striking face location and coefficient of restitution (COR) for each of a plurality of golf clubs; (d) calculating a user-specific expected COR value for each of the plurality of golf clubs based on the first data, the impact probability map, and the second data for each of the plurality of golf clubs; and (e) outputting and displaying golf club preference information based on the calculated user-specific expected COR.

A method of selecting a golf club head for a specific user, includes: (a) receiving first data comprising impact location of each of a plurality of golf swings taken by the user using a test golf club; (b) generating an impact probability map specific to the user; (c) providing second data comprising correlations between striking face location and coefficient of restitution (COR) for each of a plurality of golf clubs; (d) calculating a user-specific expected COR value for each of the plurality of golf clubs based on the first data, the impact probability map, and the second data for each of the plurality of golf clubs; and (e) outputting and displaying golf club preference information based on the calculated user-specific expected COR.

A method of selecting a golf club head for a specific user, includes: (a) receiving first data comprising impact location of each of a plurality of golf swings taken by the user using a test golf club; (b) generating an impact probability map specific to the user; (c) providing second data comprising correlations between striking face location and coefficient of restitution (COR) for each of a plurality of golf clubs; (d) calculating a user-specific expected COR value for each of the plurality of golf clubs based on the first data, the impact probability map, and the second data for each of the plurality of golf clubs; and (e) outputting and displaying golf club preference information based on the calculated user-specific expected COR.

A method of selecting a golf club head for a specific user, includes: (a) receiving first data comprising impact location of each of a plurality of golf swings taken by the user using a test golf club; (b) generating an impact probability map specific to the user; (c) providing second data comprising correlations between striking face location and coefficient of restitution (COR) for each of a plurality of golf clubs; (d) calculating a user-specific expected COR value for each of the plurality of golf clubs based on the first data, the impact probability map, and the second data for each of the plurality of golf clubs; and (e) outputting and displaying golf club preference information based on the calculated user-specific expected COR.

An equipment fitting system that measures swings by a user of different pieces of equipment with inertial sensors, and analyzes sensor data to recommend which piece of equipment is optimal for the user from among those tested. Illustrative applications include fitting of baseball bats and golf clubs. Swing metrics calculated from sensor data may include an acceleration metric, a speed metric, and a momentum metric; these metrics may be combined into a metrics score for each piece of equipment. Other factors may be included in an overall score, such as the user's subjective score for each piece of equipment, and ratings from experts or other consumers. Users may assign the relative importance for the different factors to calculate an overall equipment score.

A method of measuring and recording at least one performance variable of a golf club head.

A method of measuring and recording at least one performance variable of a golf club head.

The present invention relates to a method for characterizing a racket head of a ball game racket frame as well as to the representation of a racket head.