An object of the present invention is to provide a golf ball traveling a great flight distance. The present invention provides a golf ball comprising a spherical core and a cover covering the spherical core, wherein the golf ball has a ratio (t2/t1) of a time (t2) to a time (t1) of 1.05 or more in a hitting test using a driver (at a head speed of 40 m/sec), wherein the time (t1) is a time taken from a moment that the driver begins to contact with the golf ball to a moment that the golf ball reaches a maximum deformation amount, and the time (t2) is a time taken from the moment that the golf ball reaches the maximum deformation amount to a moment that the golf ball leaves the driver.

A portable device for determining whether a tennis ball is compliant with a stated deformation standard compresses a tennis ball by application of a pre-determined pre-load followed by a pre-determined force. A scale is provided for measuring the deformation of the tennis ball after it is compressed. The device includes several plate members disposed in parallel and relatively movable a controllable amount by a shifting mechanism.

A measuring device includes a base station, a weight station unit and a controller. A mount station unit is connected to the weight station unit and has first and second mounting bases connected by a swing arm. The first mounting base is moveably supported on the first weight scale, and the second mounted base is moveably supported on the second weight scale. An adjustable holding part is disposed at one end of the first mounting base and a support is disposed at another end of the first mounting base adjacent the swing arm. A sports article is mountable on the first mounting base between the adjustable holding part and the support.

A thickness checking pointer for billiard practice is provided, where while being fitted to a finger supporting a cue stick, the thickness checking pointer guides the cue stick to move in a straight line during forward and backward preparation motion or hitting motion of the cue stick, and emits a horizontal light beam in a travelling direction of the cue stick, so as to not only check which shape into which a cue ball and an object ball are arranged on the same straight line as the cue stick but also estimate the degree of thickness by which the cue ball moved upon hitting collides with the object ball, thereby enabling even beginners to easily understand billiards.

Articles of sports equipment, such as striking implements (e.g., sticks) and wearable articles (e.g., skates, helmets) for playing hockey or other activities, in which at least one of the characteristics (e.g., stiffness) of the articles of sports equipment is adaptable and can be altered during use of the sports equipment, such as by comprising an alterable component coupled to a controller, by comprising an alterable component that is autonomously alterable, and/or by an alterable component that can be altered in response to a command of a remote device.

A system for quickly determining if a hockey skate blade is bent is disclosed. The system is a quick and effective way to determine if a Hockey Skate Blade is bent which will affect the ability for the blade to be sharpened and skating performance. The disclosed system is a simple way to ensure skating performance and blade sharpness are optimized.

Provided is an impact point estimation apparatus that is capable of estimating, easily and with high accuracy, an impact point on a face surface of a golf club head at the time of a golf swing. The impact point estimation apparatus includes an acquisition part configured to acquire time-series sensor data that is output from at least one of an angular velocity sensor and an acceleration sensor attached to at least one of a grip and a shaft of a golf club and an estimation part configured to estimate the impact point, according to a shaft characteristic which is a characteristic of the shaft, based on the sensor data.

A golf club includes a club head having a volume of greater than about 360 cm.sup.3 and a mass less than 200 g. A shaft attachable to the club head has a tip end, a butt end, and a shaft balance point distance, BP.sub.s, as measured from the butt end, of no more than 19 inches. And the golf club has a mass less than 300 g.

A system for visually tracking the trajectory of an in-flight golf ball through an x-y-z space above a driving range includes a plurality of cameras for respectively creating a video stream of the x-y-z space. Each video stream is presented on a dedicated camera focal plane with information on respective azimuth angles and elevation angles from the particular camera to the in-flight golf ball. A central computer is connected with the camera focal plane of each camera to identify a start point for the golf ball, to track its trajectory in the x-y-z space, and to filter out background clutter. A visual display is provided to show the in-flight golf ball from its start point to a target point in real time.

An apparatus for measuring a deformation distribution of an object having a longitudinal dimension comprises a structure for supporting the object. A sensor unit comprises a base, a contact member having a body connected to the base by a rotational joint such rotational degrees of freedom are provided between the base and the contact member, an end of the body configured to contact and move along the object, and at least one sensor for determining an orientation of the body relative to the base. A displacement module enables relative movement between the sensor unit and the structure for the sensor unit to relatively move along the object in the longitudinal dimension. A method and system for measuring a rigidity distribution of an object having a longitudinal dimension are also provided.