Abstract: A fitting device for selecting a golf club suitable for a golfer comprises: an acquisition part that acquires measurement values obtained by measuring a golfer's swing motion of a first golf club with a measuring device; and a calculation part that calculates a swing index related to the swing motion based on the measurement values; a determination part that determines, based on the swing index, a second optimum characteristic index indicating characteristics of a shaft for a second golf club different from the first golf club; and a selection part that selects at least a shaft for the second golf club that matches the second optimum characteristic index.

Abstract: Provided is a fitting apparatus configured to acquire measurement data obtained by measuring a swing action of a test club by a golfer, calculate one or more first indices representing an amount of change in an openness of a face surface of a head included in the test club at a time of the swing action based on the measurement data, calculate one or more second indices representing a characteristic of the swing action based on the measurement data, select a balance of a golf club suitable for the golfer, according to the one or more first indices, select at least one of a weight and a moment of inertia of a golf club suitable for the golfer, according to the one or more second indices, and select a golf club having the balance and the at least one of the weight and the moment of inertia.

Abstract: In a head, a center vertical cross section passing through a face center satisfies the following (a) and (b): (a) when a boundary point between an inner surface of a crown portion and an inner surface of a face portion is defined as a CF inner surface boundary point, a curvature radius of a head inner surface at the CF inner surface boundary point is 6.0 mm or greater and 10.0 mm or less, and the head thickness at the CF inner surface boundary point is 2.0 mm or greater; and (b) when a spot located 10 mm apart from the CF inner surface boundary point toward the crown side is defined as a spot C10, the head thickness reduces gradually from the CF inner surface boundary point to the spot C10, and the head thickness at the spot C10 is 1.0 mm or less.

Abstract: Provided is a fitting apparatus configured to acquire measurement data obtained by measuring a swing action of a test club by a golfer with a measurement device, calculate an amount of change in an attitude of a face surface of a head included in the test club in a period before impact at a time of the swing action, based on the measurement data, and select a balance of a golf club suitable for the golfer, according to the amount of change.

Abstract: A head includes a body member that has an opening, and a face member that includes a striking face and closes the opening. The face member includes a face portion that forms the striking face, and a peripheral portion that extends from a peripheral edge of the face portion toward a back side. The peripheral portion of the face member is welded to the body member. A weld bead that juts from the inner surface of the head is formed at a boundary position between the peripheral portion and the body member. A wall thickness at a face-side end point of the weld bead is greater than a wall thickness at a body-side end point of the weld bead. The peripheral portion has a length of less than or equal to 6 mm.

Abstract: A golf club includes a head; a shaft having a tip end and a butt end; and a grip. The golf club has a length of greater than or equal to 45.0 inches. The head has a weight of greater than or equal to 195 g. The golf club has a club moment about a rotation center of less than or equal to 22.74 (kg·cm), the rotation center being a point 100 mm away from a butt end of the grip. The shaft may have a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 280 g. A butt end region having a distance from the butt end of the grip of 100 mm or less may have a weight of greater than or equal to 27 g. This golf club can exhibit an on-plane effect.

Abstract: In a head, a center vertical cross section passing through a face center satisfies the following (a) and (b): (a) when a boundary point between an inner surface of a crown portion and an inner surface of a face portion is defined as a CF inner surface boundary point, a curvature radius of a head inner surface at the CF inner surface boundary point is 6.0 mm or greater and 10.0 mm or less, and the head thickness at the CF inner surface boundary point is 2.0 mm or greater; and (b) when a spot located 10 mm apart from the CF inner surface boundary point toward the crown side is defined as a spot C10, the head thickness reduces gradually from the CF inner surface boundary point to the spot C10, and the head thickness at the spot C10 is 1.0 mm or less.

Abstract: A golf club includes a head; a shaft; and a grip. The head has a weight Wh of greater than or equal to 195 g. The golf club has a club length Lc of greater than or equal to 45.0 inches. The golf club has a club weight Wc of greater than or equal to 295 g. The golf club has a swing moment of inertia Isw of less than or equal to 5470×103 (g·cm2). The swing moment of inertia Isw (g·cm2) is calculated by the following formula (1): Isw=Wc×(Lg+40)2+Ic??(1), where Wc represents the club weight (g), Lg represents a distance (cm) in an axial direction between a butt end of the grip and a center of gravity of the golf club, and Ic represents a moment of inertia (g·cm2) of the golf club about the center of gravity of the golf club.

Abstract: Provided is a sensitive golf club with a sensor unit. The sensor unit includes a battery, a sensor module configured to measure sensor data indicating a state of the golf club using power from the battery, a communications unit configured to wirelessly transmit the sensor data to an external device using power from the battery, and a control unit configured to control operation of the sensor module and the communications unit using power from the battery. The sensor unit has an A mode, and a B mode in which operation of the communications unit is suppressed compared to the A mode. The control unit is configured to judge whether or not the golf club is prepared for a shot based on the sensor data, and switch between the A mode and B mode based on whether or not the golf club is prepared for a shot.

Abstract: A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. The shaft has a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 275 g and less than or equal to 300 g. W1/W3 is greater than or equal to 0.40, where W1 represents a weight (g) of the butt end region, and W3 represents a weight (g) of the shaft-grip-weight portion.

Abstract: A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The golf club has a length of greater than or equal to 45.0 inches. The golf club has a weight of less than 295 g. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. W1/W3 is greater than or equal to 0.40, where W1 represents a weight (g) of the butt end region, and W3 represents a weight (g) of the shaft-grip-weight portion.

Abstract: Provided is a fitting apparatus configured to acquire measurement data obtained by measuring a swing action of a test club by a golfer, calculate one or more first indices representing an amount of change in an openness of a face surface of a head included in the test club at a time of the swing action based on the measurement data, calculate one or more second indices representing a characteristic of the swing action based on the measurement data, select a balance of a golf club suitable for the golfer, according to the one or more first indices, select at least one of a weight and a moment of inertia of a golf club suitable for the golfer, according to the one or more second indices, and select a golf club having the balance and the at least one of the weight and the moment of inertia.

Abstract: Provided is a fitting apparatus configured to acquire measurement data obtained by measuring a swing action of a test club by a golfer with a measurement device, calculate an amount of change in an attitude of a face surface of a head included in the test club in a period before impact at a time of the swing action, based on the measurement data, and select a balance of a golf club suitable for the golfer, according to the amount of change.

Abstract: A golf club 2 includes a head 4, a shaft 6, and a grip 8. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2760 (kg·cm2) or greater and less than 2820 (kg·cm2). Isw/Ige is equal to or less than 2.42. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg·cm2). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.

Abstract: A golf club includes a head; a shaft having a tip end and a butt end; and a grip. The golf club has a length of greater than or equal to 45.0 inches. The head has a weight of greater than or equal to 195 g. The golf club has a club moment about a rotation center of less than or equal to 22.74 (kg·cm), the rotation center being a point 100 mm away from a butt end of the grip. The shaft may have a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 280 g. A butt end region having a distance from the butt end of the grip of 100 mm or less may have a weight of greater than or equal to 27 g. This golf club can exhibit an on-plane effect.

Abstract: A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. The shaft has a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 275 g and less than or equal to 300 g. W1/W3 is greater than or equal to 0.40, where W1 represents a weight (g) of the butt end region, and W3 represents a weight (g) of the shaft-grip-weight portion.

Abstract: A golf club includes a head; a shaft; and a grip. The head has a weight Wh of greater than or equal to 195 g. The golf club has a club length Lc of greater than or equal to 45.0 inches. The golf club has a club weight Wc of greater than or equal to 295 g. The golf club has a swing moment of inertia Isw of less than or equal to 5470×103 (g·cm2). The swing moment of inertia Isw (g·cm2) is calculated by the following formula (1): Isw=Wc×(Lg+40)2+Ic ??(1), where Wc represents the club weight (g), Lg represents a distance (cm) in an axial direction between a butt end of the grip and a center of gravity of the golf club, and Ic represents a moment of inertia (g·cm2) of the golf club about the center of gravity of the golf club.

Abstract: A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The golf club has a length of greater than or equal to 45.0 inches. The golf club has a weight of less than 295 g. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. W1/W3 is greater than or equal to 0.40, where W1 represents a weight (g) of the butt end region, and W3 represents a weight (g) of the shaft-grip-weight portion.

Abstract: 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.

Abstract: Provided is a virtual golf simulation apparatus including a processor. The processor is connected to an output device and is configured to acquire measurement data obtained by using a measurement device to measure an actual shot performed by a golfer, analyze a shot characteristic of the golfer based on the measurement data, virtually generate a virtual golfer having a shot characteristic corresponding to the shot characteristic of the golfer, receive, from the golfer, an instruction instructing the virtual golfer to perform an action in a virtual space, simulate a shot of the virtual golfer in the virtual space in accordance with the instruction, and output a result of the simulation to the output device.