Abstract: Provided is a system for measuring golf club deformation that can easily measure golf club deformation during a golfer's golf swing as usual. A measurement system (1) according to the present invention is provided with an image pickup apparatus (4), attached to a golf club (3) and facing a direction that includes at least one identifier attached to the golf club (3) for specification of a position on the golf club (3), and with a measurement apparatus (2) that measures the golf club deformation based on position information of the at least one identifier, the position information being acquired from an image of the golf club captured by the image pickup apparatus (4) during a swing.

Abstract: Provided is a golf swing classification method that is capable of optimizing selection of a golf club. A golf swing classification method when a golf club hits a golf ball according to the present invention includes the steps of: acquiring acceleration in at least a single point on the golf club or in at least one point that follows the single point during the golf swing; and mapping a behavior of the golf club based on a time period from a time point when an absolute value of the acceleration is at a maximum to a time point when the golf club hits the golf ball.

Abstract: In a hybrid vehicle that selects a series mode in which an engine drives a motor generator to generate electric power and a driving motor drives drive wheels, fuel supply to the engine is stopped and motoring in which the motor generator forcedly drives the engine can be performed, failure determination of a front O2 sensor and a rear O2 sensor provided in an exhaust passage of the engine can be performed based on a change in a detection value of the sensors when the fuel supply is stopped, and a throttle valve of the engine is forcedly opened in the motoring.

Abstract: In a hybrid vehicle that selects a series mode in which an engine drives a motor generator to generate electric power and a driving motor drives drive wheels, the series mode is suspended to temporarily stop fuel supply to the engine, and the motor generator forcedly drives the engine using electric power supplied from a driving battery to perform motoring, and failure determination of the O2 sensors is performed based on oxygen concentrations of an exhaust gas from the engine detected by a front O2 sensor and a rear O2 sensor when the fuel supply to the engine is stopped and when the fuel supply is restarted after finish of the motoring.

Abstract: A changeover valve is opened, reference pressure Pb is detected, a monitoring timer is set to 0, a purge process is started, the changeover valve is closed, a pump is operated, and the monitoring timer t is started. Then, a canister internal pressure Pc is detected, a pressure deviation ?Pc is calculated from the reference pressure Pb and the canister pressure Pc, and it is determined if there is abnormality such as a leak or obstruction in a fuel evaporative gas treatment portion when the pressure deviation ?Pc is a first threshold ?P1 or higher. It is determined that there is a leak when the pressure deviation ?Pc is less than a second threshold ?P2, and it is determined that there is an obstruction when the pressure deviation ?Pc is the second threshold ?P2 or higher.

Abstract: A purge solenoid valve is opened to introduce an atmospheric pressure into a fuel tank, the purge solenoid valve is closed to operate a negative pressure pump, and set an internal pressure of the tank to a reference pressure Pb. Then, a changeover valve is closed, and the purge solenoid valve is opened to cause a canister to communicate with an intake passage. Further, the changeover valve is opened, and the purge solenoid valve is closed. Then, a first tank internal pressure Po is detected and subtracted from the reference pressure Pb. If a calculated first pressure deviation ?Po is larger than a first threshold ?P1, it is determined that there is no open sticking in a sealing valve.

Abstract: An apparatus includes a dynamo-electric machine driving an engine, and a calculator calculating an increment in a crank angular acceleration of the engine every certain period from a base time after the driving of the engine by the dynamo-electric machine. The apparatus further includes a determiner determining that the engine has started by the dynamo-electric machine on a condition that the increment calculated by the calculator exceeds a standard value.

Abstract: An object of the present invention is to provide a system and method for measurement and analysis of a behavior of a golf club head. Specifically, the system comprises a measurement and analysis device having a marker recognition and positional information acquisition unit for recognizing the at least one marker and acquiring positional information of the recognized at least one marker, a vector calculation unit for calculating a first vector representing a direction of the head and a second vector representing a tangent vector of a trajectory of the head during the golf swing, and a vector angle change acquisition unit for calculating a vector angle between the first vector and the second vector and acquiring a time series change of the calculated vector angle.

Abstract: An object of the present invention is to provide a golf club classification method capable of classifying a golf swing precisely. Specifically, the present invention provides a classification method comprising steps of: partitioning the golf swing of the golfer into golf swing trajectories of a back swing, a down swing, and a follow through so as to determine a stable point in the golf swing trajectories as an origin for any two of the trajectories and to assign a two dimensional coordinate to the two golf swing trajectories; determining straight lines connecting each of one point selected within each of the two golf swing trajectories and the origin; calculating angles between each of the determined straight lines and the horizontal line respectively for the two golf swing trajectories; and classifying the golf swing based on a difference between the calculated angles.

Abstract: The accuracy or computation speed of mechanical analysis of a golf ball using the finite element method is increased. In the mechanical analysis, a model representing the golf ball is prepared on a computer, and computation is made by the finite element method using elements and nodes. At this time, the elements are made solid elements of hexahedron, the aspect ratio of the shape of each element is set so as to be not lower than 1.0 and not substantially higher than 6.5, and nodes are provided on the sides and at the vertexes of the hexahedron of element.

Abstract: A golf club head with a leading end of a shaft mountable thereon, the golf club head includes: a head main body, formed with a hosel insertion hole; a hosel, formed with a shaft case insertion hole and removably mounted in the hosel insertion hole; and a shaft case, formed with a shaft insertion hole and removably mounted in the shaft case insertion hole.

Abstract: The system (1) for measuring a golf swing according to the present invention is provided with at least two image pickup apparatuses that each capture an image of a golf club (5) that includes at least one head identifier attached to the head and with a measurement apparatus that measures the force acting on the head of the golf club (5) based on position information of the at least one head identifier, the position information being acquired from the images of the golf club (5) captured during a swing.

Abstract: A golf club head includes: a head main body formed with a hosel column inserting hole; a hosel column which is formed with a shaft inserting hole and is installed on the hosel column inserting hole; a bolt inserting hole penetrating from a sole side of the head main body to the hosel column inserting hole; and a bolt which is inserted into the bolt inserting hole and is screwed into the hosel column, wherein: the hosel column includes a trunk portion provided with a shaft inserting hole, and a leg portion which protrudes from a lower end surface of the trunk portion and is inserted into the hosel column inserting hole; and at least a lower end side of the leg portion and an inner portion of the hosel column inserting hole are polygonal sectional shape portions and are engaged with each other.

Abstract: A golf club head includes: a head main body having a shaft holder inserting hole; a shaft holder which has a shaft inserting hole and is attachably and detachably installed in the shaft holder inserting hole; a bolt inserting hole which penetrates from a sole side of the head main body to the shaft holder inserting hole; and a bolt which is inserted into the bolt inserting hole, screwed into the shaft holder, and fixes the shaft holder to the head main body, an axis center of the shaft inserting hole and an axis center of the shaft holder inserting hole being non-coaxial shapes, wherein a lower end side of the shaft holder and an inner portion of the shaft holder inserting hole are polygonal sectional shape portions and are engaged with each other.

Abstract: The method according to the present invention includes a step of dividing a golfer's golf swing into three golf swing trajectories, namely a backswing, downswing, and follow through, and allocating each golf swing trajectory to a 2D coordinate system formed by a horizontal axis and a vertical axis with a given point among the golf swing trajectories as the origin; a step of establishing, for each of the three golf swing trajectories, a line connecting the origin and a point selected in the golf swing trajectory and calculating an angle enclosed between each established line and the horizontal axis; and a step of calculating an angular difference between any two angles among the calculated angles, plotting the angular difference on a 2D map, and classifying the golf swing.

Abstract: Provided is a swing simulation system capable of simulating a swing without amplifying errors contained in measured values on three-dimensional coordinates of a grip during the swing. The simulation system according to the present invention includes: at least two imaging devices for imaging identification features capable of identifying a closed virtual plane that follows a grip of a golf club during a swing; and a simulation apparatus for simulating a behavior of the golf club during the swing, based on position information on the virtual plane.

Abstract: A golf club head having a hollow construction includes a face part having a ball-impacting surface and a first main rib and a second main rib disposed on the inner surface of the face part. The first main rib extends from a crown side to a sole side, and the second main rib extends from a hosel side to a toe-side part of the sole side, the first and second main ribs intersecting each other. The material thickness on a toe side of the face part, with the first main rib being the boundary, is formed so as to be thinner than the material thickness on a heel side of the face part.

Abstract: A face portion of a golf club head includes first to fourth main ribs on an inner surface of the head. The first main rib extends from a center portion of the face portion toward a crown, and the second main rib extends from the center portion toward a sole. The face portion is formed to have such a thickness that the center portion, the first main rib, and the second main rib become thinner in this order. The third and fourth main ribs extend from the center portion in outward directions of the face portion.

Abstract: A golf club head includes a head body that forms a crown portion, a sole portion, and a side portion and has an opening portion in a portion corresponding to a face portion, and a face member that is joined to the opening portion and forms the face portion. A first notch portion formed in a heel-side portion of the peripheral edge of the opening portion, and a second notch portion formed in a toe-side portion of the peripheral edge. The face member includes a first extending portion that seals the first notch portion, and a second extending portion that seals the second notch portion. The and second extending portions are more rigid than a portion of the peripheral edge.

Abstract: A leakage judgment with respect to a fuel tank is carried out. If the fuel tank is not leaking, a leakage judgment with respect to a canister is carried out. If there is a possibility of leakage in the fuel tank, a leakage judgment with respect to the fuel tank and the canister is carried out. If it is judged that there is leakage in the fuel tank and the canister, the leakage judgment with respect to the canister is carried out.