JP6300196B2 - Exercise equipment behavior analysis apparatus, exercise equipment behavior analysis method, and exercise equipment behavior analysis program - Google Patents

Description

  The present invention relates to a motion tool behavior analysis apparatus, a motion tool behavior analysis method, a motion tool behavior analysis program, and the like.

  In golf, which is an example of movement, the trajectory of the hit ball greatly depends on the direction of the club face at the time of impact. The direction of the club face is affected by the deflection of the shaft during the swing. Shaft stiffness distribution affects shaft deflection. Therefore, if the deflection of the shaft during the swing is accurately analyzed, a golf club design suitable for the golfer can be realized.

  For example, as disclosed in Patent Document 1, an analysis of shaft deflection is attempted by a motion tool behavior analysis device. In the exercise tool behavior analysis apparatus described in Patent Document 1, two strain gauges are attached to the shaft of a golf club. A cross-correlation function is derived between the strain gauge outputs. The cross-correlation function specifies the transfer of deformation from the grip side of the shaft to the head side. Thus, the dynamic behavior of the shaft during the swing is known.

JP 2003-102886 A

  However, in Patent Document 1, although it is possible to measure the bending characteristics of the place where the strain gauge is attached, in order to know the distribution of the bending characteristics of the entire shaft, it is necessary to attach a plurality of strain gauges to the shaft of the golf club. Convenience was bad.

  According to at least one aspect of the present invention, a sports equipment behavior analysis device, a sports equipment behavior analysis method, and a sports equipment behavior analysis program capable of providing an index greatly useful for designing a sports equipment represented by a golf club are realized. To do.

  (1) One aspect of the present invention relates to an exercise tool behavior analysis apparatus including an arithmetic unit that calculates a concentrated moment that acts on both end portions of the shaft during a swing using an output of an inertial sensor attached to the shaft of the exercise tool. .

  The present inventor has found that the dynamic behavior of the deflection and torsion of the shaft during the swing is quantitatively expressed by the concentrated moment acting on both end portions of the shaft regarding the dynamic behavior of the shaft during the swing. The inertial force of the shaft is measured using an inertial sensor, and concentrated moments generated at both ends of the shaft are derived based on the measured inertial force. The amount of shaft deflection and torsion generated during the swing from the concentrated moment is objectively specified numerically, and can provide an index that is very useful for designing the exercise tool.

  (2) The shaft is connected to the head, and one end portion of the both end portions of the shaft is a grip portion, and the other end portion is a connecting portion between the shaft and the head. In an exercise tool in which a shaft and a head are connected, such as a golf club, it is possible to calculate the amount of deflection and the amount of twist generated in the shaft during a swing.

  (3) The output of the inertial sensor includes at least one of an acceleration signal that specifies acceleration generated in the exercise tool and an angular velocity signal that specifies angular velocity generated in the exercise tool. The concentration moment can be calculated using acceleration and angular velocity.

  (4) The calculation unit calculates a force acting on the head by multiplying the mass of the head and an acceleration generated in the head during a swing, and uses the force acting on the head to calculate the concentration moment. Can be calculated. The acceleration generated in the head is estimated by using a mathematical expression from the output of an inertial sensor attached to the shaft, for example. The concentration moment can be calculated using the force acting on the head.

  (5) The calculation unit calculates the concentration moment of the grip portion using a force acting on the head and a distance from the grip portion of the shaft portion to the center of gravity of the head.

  (6) The calculation unit calculates the concentrated moment of the connecting portion using a force acting on the head and a distance from the connecting portion of the shaft portion to the center of gravity of the head. By using the concentrated moments at both ends of the shaft thus obtained, it is possible to calculate the bending moment distribution along the long axis direction of the shaft and the torsional moment around the long axis of the shaft.

  (7) The acceleration generated on the head side is the acceleration and angular velocity obtained from the output of the inertial sensor attached to the shaft, and the distance from the position where the inertial sensor is attached to the shaft to the center of gravity of the head And are estimated using Even if the inertial sensor is not attached to the head, the acceleration acting on the head can be estimated from the inertial sensor attached to the shaft, so that convenience is improved.

  (8) The calculation unit can calculate a bending moment distribution along a long axis direction in which the shaft extends using the concentrated moment. The degree of bending of the shaft is estimated for each part along the long axis direction of the shaft according to the distribution of the bending moment.

  (9) The shaft is connected to a head, and the calculation unit can calculate a deflection in a direction perpendicular to the major axis direction of the shaft and along the face surface of the head. The amount of deflection of the shaft is estimated according to the distribution of the bending moment. In particular, by extracting the deflection in the y-axis direction perpendicular to the axial direction of the shaft and along the face surface of the head, for example, the deflection amount in the y-axis direction can be displayed numerically.

  (10) The shaft is connected to a head, and the calculation unit can calculate a deflection in a direction perpendicular to the major axis direction of the shaft and perpendicular to the face surface of the head. The amount of deflection of the shaft is estimated according to the distribution of the bending moment. In particular, since the deflection is taken out in the z-axis direction perpendicular to the major axis direction of the shaft and perpendicular to the face surface of the head, for example, the deflection amount in the z-axis direction can be displayed numerically.

  (11) The calculation unit can calculate a torsion around a long axis along which the shaft extends. The inertial sensor measures the inertial force of the shaft. Based on the measured inertial force, a concentrated moment around the long axis of the shaft is derived. The amount of torsion of the shaft is estimated based on the concentrated moment around the long axis. This amount of twist can provide an indication of the dynamic behavior of the shaft during the swing.

  (12) In another aspect of the present invention, a step of receiving an output of an inertial sensor attached to a shaft of an exercise tool and a concentration moment acting on both end portions of the shaft are calculated using the output of the inertial sensor. And a motion tool behavior analysis method comprising the steps.

  The present inventor has found that the dynamic behavior of the shaft during the swing is quantitatively expressed by the concentrated moment acting on both end portions of the shaft regarding the dynamic behavior of the shaft during the swing. The inertial force of the shaft is measured using an inertial sensor, and concentrated moments generated at both ends of the shaft are derived based on the measured inertial force. The amount of shaft deflection and torsion generated during the swing from the concentrated moment is objectively specified numerically, and can provide an index that is very useful for designing the exercise tool.

  (13) Another aspect of the present invention relates to an exercise tool behavior analysis program including a procedure for calculating a concentrated moment acting on both end portions of a shaft of an exercise tool using an output of an inertial sensor.

  The present inventor has found that the dynamic behavior of the shaft during the swing is quantitatively expressed by the concentrated moment acting on both end portions of the shaft regarding the dynamic behavior of the shaft during the swing. The inertial force of the shaft is measured using an inertial sensor, and concentrated moments generated at both ends of the shaft are derived based on the measured inertial force. The amount of shaft deflection and torsion generated during the swing from the concentrated moment is objectively specified numerically, and can provide an index that is very useful for designing the exercise tool.

It is a conceptual diagram which shows roughly the structure of the golf swing analyzer which concerns on one Embodiment of this invention. It is a conceptual diagram which shows a swing model roughly. It is a block diagram which shows roughly the structure of the arithmetic processing circuit which concerns on one Embodiment. It is a graph which shows an example of the measurement result of bending rigidity.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are essential as means for solving the present invention. Not necessarily. Bold italics in mathematical expressions indicate vectors, and the same symbols in the text correspond to bold italics and italics in mathematical expressions.

(1) Configuration of Golf Swing Analysis Device FIG. 1 schematically shows a configuration of a golf swing analysis device (exercise tool behavior analysis device) 11 according to an embodiment of the present invention. The golf swing analysis device 11 includes an inertial sensor 12. For example, an acceleration sensor or a gyro sensor is incorporated in the inertial sensor 12. The acceleration sensor can individually detect acceleration in three axial directions orthogonal to each other. The gyro sensor can individually detect the angular velocity around each of three axes orthogonal to each other. The inertial sensor 12 outputs a detection signal. The acceleration and angular velocity are specified for each axis in the detection signal. The acceleration sensor and the gyro sensor detect acceleration and angular velocity information with relatively high accuracy. The inertial sensor 12 may be a multi-axis sensor that can detect inertial amounts around a plurality of axes with one element, or a single axis that can detect an inertial amount acting on one detection axis with one element. It may be a sensor in which a plurality of sensors are mounted.

  The inertial sensor 12 is attached to a golf club (exercise tool) 13. The golf club 13 includes a shaft 13a and a grip 13b, and the grip 13b is grasped by a hand. The grip 13b is formed along the long axis from which the shaft 13a extends. The shaft 13a has rigidity characteristics. A head 13c is coupled to the tip of the shaft 13a. The head 13c has a center of gravity at a position eccentric from the long axis of the shaft 13a.

  The inertial sensor 12 is attached to an arbitrary portion of the shaft 13a or the grip 13b of the golf club 13. The inertial sensor 12 may be fixed to the golf club 13 so as not to be relatively movable. Here, when the inertial sensor 12 is attached, one of the detection axes of the inertial sensor 12 is aligned with the axis of the shaft 13a, and the other detection axis of the inertial sensor 12 is aligned with the direction along the face surface of the head 13c. It is desirable to be included.

  The golf swing analyzing apparatus 11 includes an arithmetic processing circuit (arithmetic unit) 14. An inertial sensor 12 is connected to the arithmetic processing circuit 14. In connection, a predetermined interface circuit 15 is connected to the arithmetic processing circuit 14. The interface circuit 15 may be connected to the inertial sensor 12 by wire or may be connected to the inertial sensor 12 by wireless. A detection signal is supplied from the inertial sensor 12 to the arithmetic processing circuit 14.

  A storage device 16 is connected to the arithmetic processing circuit 14. The storage device 16 can store, for example, a golf swing analysis software program 17 and related data. The arithmetic processing circuit 14 executes a golf swing analysis software program 17 to realize a golf swing analysis method. The storage device 16 can include a DRAM (Dynamic Random Access Memory), a mass storage device unit, a non-volatile memory, and the like. For example, in the DRAM, the golf swing analysis software program 17 is temporarily held when the golf swing analysis method is executed. A golf swing analysis software program 17 and data are stored in a mass storage unit such as a hard disk drive (HDD). The nonvolatile memory stores a relatively small capacity program such as BIOS (basic input / output system) and data.

  An image processing circuit 18 is connected to the arithmetic processing circuit 14. The arithmetic processing circuit 14 sends predetermined image data to the image processing circuit 18. A display device 19 is connected to the image processing circuit 18. A predetermined interface circuit (not shown) is connected to the image processing circuit 18 for connection. The image processing circuit 18 sends an image signal to the display device 19 according to the input image data. An image specified by the image signal is displayed on the screen of the display device 19. The display device 19 is a liquid crystal display or other flat panel display. Here, the arithmetic processing circuit 14, the storage device 16, and the image processing circuit 18 are provided as a computer device, for example.

  An input device 21 is connected to the arithmetic processing circuit 14. The input device 21 includes at least alphabet keys and numeric keys. Character information and numerical information are input from the input device 21 to the arithmetic processing circuit 14. The input device 21 may be composed of a keyboard, for example. The combination of the computer device and the keyboard may be replaced with, for example, a smartphone, a mobile phone terminal, a tablet PC (personal computer), or the like.

(2) Configuration of Swing Model The arithmetic processing circuit 14 performs arithmetic processing using the swing model shown in FIG. Both end portions are defined as a grip end 24 and a head end 25 of the shaft 13a. Here, the grip end 24 is set as a grip portion of the grip portion, and the head end 25 is set as a connecting portion of the shaft 13a and the head 13c. A coordinate system is set at the grip end 24. The x-axis of the coordinate system is specified in the direction in which the grip 13b extends. Joint grip end 24 has a total of six degrees of freedom of the three degrees of freedom of rotation with three degrees of freedom of position, that position is identified by the position vector x _w. The center of gravity of each position of the head end 25 and the head 13c of the shaft 13a is identified by a position vector _x l, _{x p,} the position of the inertial sensor 12 can be located at the position vector _{x s.} The distance between the grip end 24 and the head end 25 is 1 (el). Here, EI (x) and GJ (x) mean the bending stiffness distribution and the torsional stiffness distribution of the shaft 13a. The angular velocity vector of the golf club 13 is represented by ω _s . Head 13c has a mass _{m p.} The position vector of the head end 25 with respect to the grip end 24 is represented by L _p , and the position vector from the head end 25 of the shaft 13 a to the center of gravity of the head 13 c is represented by r _p .

ここで、ａ_ｓは、慣性センサー１２の出力から得られる加速度（重力加速度（ベクトル）ｇを含む）を示し、ω_ｓは、慣性センサー１２の出力から得られる角速度を示し、Ｌ_ｓｐは慣性センサー１２からヘッド１３ｃの重心までの距離（位置ベクトル）を示す。文字上のドットは時間微分を示す。なお、演算子「×」はベクトルの外積を示す。グリップ端２４の加速度や角速度は慣性センサー１２の計測値から算出される。［数１］の下式を用いて、シャフト１３ａに装着した慣性センサー１２からヘッド１３ｃに作用する加速度（ベクトル）ａ_ｐを推定して力（ベクトル）Ｆ_ｐを算出する。なお、慣性センサー１２をヘッド１３ｃまたはヘッド１３ｃ近くのシャフト１３ａに装着する場合においては、［数１］の上辺の加速度（ベクトル）ａ_ｐに慣性センサー１２の出力を直接入力して力（ベクトル）Ｆ_ｐを求めることができる。また、ここでは、Ｌ_ｓｐは慣性センサー１２が取り付けられた位置からヘッド１３ｃの重心位置ｘ_ｐまでの距離としているが、近似的に慣性センサー１２が取り付けられた位置からシャフト１３ａとヘッド１３ｃの連結部分までの距離（位置ベクトル）をＬ_ｓｐとして算出してもよい。力算出部２８は［数１］を用いて力Ｆ_ｐを算出し、力信号を出力する。 (3) Configuration of Arithmetic Processing Circuit FIG. 3 schematically shows the configuration of the arithmetic processing circuit 14. The arithmetic processing circuit 14 includes a force calculation unit 28. An acceleration signal and an angular velocity signal are input from the inertial sensor 12 to the force calculation unit 28. Force calculation unit 28, based on the acceleration and angular velocity, and calculates the force (vector) _{F p} acting on the head 13c. In the calculation, the force calculation unit 28 acquires mass data of the head 13c. Mass _{m p} of the head 13c is described in the mass data. The mass data may be stored in the storage device 16 in advance. When the acceleration (vector) acting on the head 13c is _ap , the force (vector) _Fp is calculated according to the following equation.

Here, a _s indicates an acceleration (including gravitational acceleration (vector) g) obtained from the output of the inertial sensor 12, ω _s indicates an angular velocity obtained from the output of the inertial sensor 12, and _Lsp is an inertial sensor. 12 shows the distance (position vector) from 12 to the center of gravity of the head 13c. The dot on the letter indicates time differentiation. Note that the operator “x” indicates a vector outer product. The acceleration and angular velocity of the grip end 24 are calculated from the measured values of the inertial sensor 12. The acceleration (vector) _ap acting on the head 13c is estimated from the inertial sensor 12 mounted on the shaft 13a by using the following equation, and the force (vector) _Fp is calculated. When the inertial sensor 12 is mounted on the head 13c or the shaft 13a near the head 13c, the output of the inertial sensor 12 is directly input to the acceleration (vector) _ap of the upper side of [Equation 1] to obtain a force (vector). F _p can be determined. Further, here, L _sp is that the distance from the position where the inertial sensor 12 is attached to the center of gravity position x _p of the head 13c, approximately coupling shaft 13a and the head 13c from the position where the inertial sensor 12 is attached The distance (position vector) to the part may be calculated as _Lsp . The force calculation unit 28 calculates the force F _p using [Equation 1] and outputs a force signal.

集中モーメントＭ（ｌ）の算出にあたって第１集中モーメント算出部３１は第１位置ベクトルデータを取得する。第１位置ベクトルデータにはシャフトとヘッド１３Ｃの連結部分からヘッド１３ｃの重心までの位置ベクトルｒ_ｐが記述される。第１位置ベクトルデータは予め記憶装置１６に格納されればよい。第１集中モーメント算出部３１は第１集中モーメント信号を出力する。第１集中モーメント信号で集中モーメントＭ（ｌ）は特定される。 The arithmetic processing circuit 14 includes a first concentrated moment calculator 31 and a second concentrated moment calculator 32. The first concentration moment calculation unit 31 and the second concentration moment calculation unit 32 are connected to the force calculation unit 28, respectively. A force signal is input from the force calculator 28 to the first concentrated moment calculator 31 and the second concentrated moment calculator 32. The first concentrated moment calculator 31 calculates a concentrated moment (vector) M (l) acting on the head end 25 (x = 1) according to the following equation, for example. The concentration moment M (l) is calculated at each time at predetermined time intervals.

In calculating the concentration moment M (l), the first concentration moment calculation unit 31 acquires first position vector data. The first position vector data position vector r _p from connecting portion of the shaft and the head 13C to the center of gravity of the head 13c is described. The first position vector data may be stored in the storage device 16 in advance. The first concentration moment calculator 31 outputs a first concentration moment signal. The concentration moment M (l) is specified by the first concentration moment signal.

集中モーメントＭ（０）の算出にあたって第２集中モーメント算出部３２は第２位置ベクトルデータを取得する。第２位置ベクトルデータにはグリップ端２４からヘッド端２５までの位置ベクトルＬ_ｐが記述される。第２位置ベクトルデータは予め記憶装置１６に格納されればよい。第２集中モーメント算出部３２は第２集中モーメント信号を出力する。第２集中モーメント信号で集中モーメントＭ（０）は特定される。 The second concentration moment calculator 32 calculates the concentration moment M (0) acting on the grip end 24 (x = 0) according to the following equation, for example. The concentration moment M (0) is calculated at each time at predetermined time intervals.

In calculating the concentration moment M (0), the second concentration moment calculation unit 32 acquires second position vector data. In the second position vector data, a position vector L _p from the grip end 24 to the head end 25 is described. The second position vector data may be stored in the storage device 16 in advance. The second concentrated moment calculator 32 outputs a second concentrated moment signal. The concentration moment M (0) is specified by the second concentration moment signal.

算出にあたって曲げモーメント分布算出部３５は長さデータを取得する。長さデータにはシャフト１３ａの長さｌ（エル）が記述される。長さデータは予め記憶装置１６に格納されればよい。曲げモーメント分布算出部３５は曲げモーメント分布信号を出力する。曲げモーメント分布信号でシャフト１３ａの全長にわたって時刻ごとに曲げモーメントの分布は特定される。 The arithmetic processing circuit 14 includes a bending moment distribution calculating unit 35 and a torsional moment calculating unit 36. The bending moment distribution calculating unit 35 is connected to the first concentrated moment calculating unit 31 and the second concentrated moment calculating unit 32. The bending moment distribution calculator 35 receives the first concentrated moment signal and the second concentrated moment signal from the first concentrated moment calculator 31 and the second concentrated moment calculator 32, respectively. Based on the concentrated moment M (l) and the concentrated moment M (0), the bending moment distribution calculating unit 35 determines M _yz (0) that is the concentrated moment in the y-axis direction and the z-axis direction at the grip end 24 and the head end 25. M _yz (l), which is a concentrated moment in the y-axis direction and the z-axis direction, is obtained, and the distribution of the bending moment M _yz (x) acting in the y-axis direction and the z-axis direction of the shaft 13a is calculated according to the following equation. The distribution is calculated at each time according to the above-described time interval.

In the calculation, the bending moment distribution calculation unit 35 acquires length data. The length data describes the length l (el) of the shaft 13a. The length data may be stored in the storage device 16 in advance. The bending moment distribution calculation unit 35 outputs a bending moment distribution signal. The distribution of the bending moment is specified for each time over the entire length of the shaft 13a by the bending moment distribution signal.

算出にあたってねじりモーメント算出部３６は長さデータを取得する。ねじりモーメント算出部３６はねじりモーメント信号を出力する。ねじりモーメント信号でシャフト１３ａの全長にわたって時刻ごとにねじりモーメントは特定される。 The torsional moment calculator 36 receives the first concentrated moment signal and the second concentrated moment signal from the first concentrated moment calculator 31 and the second concentrated moment calculator 32, respectively. Based on the concentrated moment M (l) and the concentrated moment M (0), the torsional moment calculation unit 36 and the concentrated moment M _x (0) around the x axis at the grip end 24 and the concentrated around the x axis at the head end 25. A moment M _x (l) is obtained, and a torsion moment M _x acting around the x-axis of the shaft is calculated according to the following equation. The calculation is performed at each time according to the above-described time interval.

In the calculation, the torsional moment calculation unit 36 acquires length data. The torsion moment calculation unit 36 outputs a torsion moment signal. The torsion moment is specified for each time over the entire length of the shaft 13a by the torsion moment signal.

算出にあたってｙ方向たわみ算出部３７およびｚ方向たわみ算出部３８は曲げ剛性データを取得する。曲げ剛性データにはシャフト１３ａの全長にわたって曲げ剛性分布ＥＩ（ｘ）が記述される。曲げ剛性データは予め記憶装置１６に格納されればよい。ｙ方向たわみ算出部３７はｙ方向たわみ信号を出力する。ｙ方向たわみ信号で各位置（ｘ）ごとにｙ方向のたわみ量は特定される。ｚ方向たわみ算出部３８はｚ方向たわみ信号を出力する。ｚ方向たわみ信号で各位置（ｘ）ごとにｚ方向のたわみ量は特定される。 The arithmetic processing circuit 14 includes a y-direction deflection calculation unit 37 and a z-direction deflection calculation unit 38. The y-direction deflection calculation unit 37 and the z-direction deflection calculation unit 38 are connected to the bending moment distribution calculation unit 35. A bending moment distribution signal is input from the bending moment distribution calculation unit 35 to the y-direction deflection calculation unit 37 and the z-direction deflection calculation unit 38. The y-direction deflection calculation unit 37 and the z-direction deflection calculation unit 38 are based on the bending moment distribution and the bending stiffness distribution EI (x), and the y-direction deflection and z of the shaft 13a in the y-axis direction and the z-axis direction of the coordinate system according to the following equations. Each direction deflection is calculated. The deflection is calculated at each time according to the above-described time interval.

In the calculation, the y-direction deflection calculation unit 37 and the z-direction deflection calculation unit 38 acquire bending stiffness data. The bending stiffness data describes the bending stiffness distribution EI (x) over the entire length of the shaft 13a. The bending stiffness data may be stored in the storage device 16 in advance. The y-direction deflection calculation unit 37 outputs a y-direction deflection signal. A deflection amount in the y direction is specified for each position (x) in the y direction deflection signal. The z-direction deflection calculation unit 38 outputs a z-direction deflection signal. The amount of deflection in the z direction is specified for each position (x) in the z direction deflection signal.

算出にあたってねじれ角算出部３９はねじり剛性データを取得する。ねじり剛性データにはシャフト１３ａの全長にわたってねじり剛性分布ＧＪ（ｘ）が記述される。ねじり剛性データは予め記憶装置１６に格納されればよい。ねじれ角算出部３９はねじれ角信号を出力する。ねじれ角信号で各位置（ｘ）でｘ軸回りのねじれ角量は特定される。 The arithmetic processing circuit 14 includes a twist angle calculation unit 39. The torsion angle calculation unit 39 is connected to the torsion moment distribution calculation unit 36. A torsional moment signal is input to the torsional angle calculating unit 39 from the torsional moment calculating unit 36. The torsion angle calculation unit 39 calculates the torsion angle around the x axis of the shaft 13a based on the torsion moment and torsional rigidity distribution GJ (x) according to the following equation. The calculation of the twist angle is performed at each time according to the above-described time interval.

In the calculation, the torsion angle calculation unit 39 acquires torsional rigidity data. The torsional rigidity data describes the torsional rigidity distribution GJ (x) over the entire length of the shaft 13a. The torsional rigidity data may be stored in the storage device 16 in advance. The torsion angle calculation unit 39 outputs a torsion angle signal. The amount of twist angle around the x-axis is specified at each position (x) by the twist angle signal.

(4) Operation of Golf Swing Analysis Device The operation of the golf swing analysis device 11 will be briefly described. First, a golfer's golf swing is measured. Prior to the measurement, necessary information is input from the input device 21 to the arithmetic processing circuit 14. Here, according to the swing model of the golf club 13, the position vector _{r p} of the center of gravity of the mass _{m p} and the head 13c of the head 13c, the position vector _{L p} of the head end 25, the shaft 13a length l (el), flexural rigidity distribution EI (x), the torsional rigidity distribution GJ (x), the input of the position, etc. vector _{x s} of the sensor 12 is facilitated. The input information is managed under a specific identifier, for example. The identifier may identify a specific golf club 13.

  Prior to measurement, the inertial sensor 12 is attached to the shaft 13 a of the golf club 13. The inertial sensor 12 is fixed to the golf club 13 so as not to be relatively displaced. Here, one of the detection axes of the inertial sensor 12 is aligned with the axis of the shaft 13a. One of the detection axes of the inertial sensor 12 is adjusted to the hitting direction specified by the direction of the face (hitting surface).

  Prior to execution of the golf swing, measurement of the inertial sensor 12 is started. The inertial sensor 12 continuously measures acceleration and angular velocity at specific sampling intervals. The sampling interval defines the measurement resolution. The detection signal of the inertial sensor 12 is sent to the arithmetic processing circuit 14 in real time. The arithmetic processing circuit 14 receives a signal specifying the output of the inertial sensor 12.

  When the golf club 13 is shaken, the posture of the golf club 13 changes along the time axis. The inertial sensor 12 outputs a detection signal according to the posture of the golf club 13. In accordance with the output of the detection signal, the arithmetic processing circuit 14 calculates a deflection in the y-axis direction, a deflection in the z-axis direction, and a twist angle around the x-axis. The y-direction deflection signal, the z-direction deflection signal, and the twist angle signal are input to the image processing circuit 18. Thus, the amount of deflection in the y-axis direction, the amount of deflection in the z-axis direction, and the amount of twist angle around the x-axis are imaged. An image is displayed on the screen of the display device 19 according to the drawing data. The deflection in the y-axis direction reflects the deflection of the shaft 13a along the swing surface. The deflection in the z-axis direction reflects the deflection of the shaft 13a in a direction perpendicular to the face surface of the head 13c.

  The stiffness distribution EI (x) is measured by a design value specified by the shaft manufacturer or by a dedicated measuring instrument, and a characteristic as shown in FIG. 5 is obtained. In the drawing, the origin of the x axis corresponds to the grip end 24 of the shaft 13a that identifies the shaft 13a, the horizontal axis indicates the length in the long axis direction of the shaft 13a, and the vertical axis indicates the bending rigidity of the shaft. . The torsional stiffness distribution GJ (x) is also measured in advance using a dedicated measuring instrument.

  In the golf swing analyzing apparatus 11, the inertia sensor 12 measures the inertia force of the shaft 13a. Based on the measured inertial force, the concentration moment M (l) and the concentration moment M (0) are derived. In this way, it is possible to quantitatively express dynamic behavior such as the amount of deflection and the amount of torsional angle of the shaft 13a during the swing. The concentration moment M (l) and the concentration moment M (0) can provide an index useful for designing the golf club 13.

  In the golf swing analyzing apparatus 11, the output of the inertial sensor 12 includes an acceleration signal and an angular velocity signal. The acceleration is specified by the acceleration signal, and the angular velocity is specified by the angular velocity signal. The concentrated moment M (l) and the concentrated moment M (0) are calculated according to the acceleration and the angular velocity.

The concentration moment M (0) is calculated at the grip end 24 of the shaft 13a using, for example, a swing model shown in FIG. Based on the concentrated moment M _yz (0) and the concentrated moment M _x (0) at the grip end 24, the dynamic behavior of the shaft 13a is quantitatively expressed according to the force acting from the arm during the swing. On the other hand, the concentrated moment M _yz (l) and the concentrated moment M _x (l) are calculated at the head end 25 of the shaft 13a that identifies the shaft 13a by the swing model. Based on the concentrated moment M _yz (l) and the concentrated moment M _x (l) at the head end 25, the dynamic behavior of the shaft 13a is quantitatively expressed according to the force acting from the head 13c during the swing.

The bending moment distribution calculation unit 35 performs the y-axis direction and the z-axis of the shaft 13a along the long-axis direction of the shaft 13a based on the concentrated moments M _yz (l) and the concentrated moment M _yz (0) in the y-axis direction and the z-axis direction. A bending moment distribution M _yz (x) is calculated. The degree of bending of the shaft 13a is estimated for each part along the axial direction of the shaft 13a according to the bending moment distribution M _yz (x). In addition, torsional moment calculation section 36 calculates torsional moment _{M x} around the axis of the shaft 13a on the basis of intensive moment _M x (l) and concentrated moment _M x around the x-axis (0). Degree twist of the shaft 13a is estimated for each region of the shaft 13a in accordance with the torsional moment M _x.

The golf swing analyzing apparatus 11 estimates the deflection amounts of the y-axis direction component and the z-axis direction component of the shaft 13a according to the bending moment distribution M _yz (x). The deflection in the y-axis direction reflects the deflection of the shaft 13a along the face surface of the head 13c. The deflection in the z-axis direction reflects the deflection of the shaft 13a in the direction orthogonal to the x-axis and y-axis, that is, the direction orthogonal to the face surface of the head 13c.

The golf swing analyzing apparatus 11 estimates the torsion angle amount of the shaft 13a according to the torsion moment M _x (x). Such a torsion angle amount can provide an indication of the dynamic behavior of the shaft 13a during the swing.

  As described above, in the present invention, the concentrated moment generated at both ends of the shaft 13a during the swing is calculated using the output of the inertial sensor 12 attached to the shaft 13a, and the bending moment distribution of the shaft and the like are calculated from the concentrated moment. It is possible to specify the torsional moment and quantitatively output the amount of deflection and the amount of torsional angle of the shaft. In a conventional deflection measuring system using a strain gauge, it is necessary to attach a plurality of strain gauges to the shaft of the golf club in order to know the distribution of the bending characteristics of the entire shaft. It is possible to estimate the bending characteristics and the torsional angle characteristics of the entire shaft 13a only by mounting one inertial sensor 12. As another effect, since the present invention uses the inertial sensor 12, it is possible to perform swing trajectory calculation and swing analysis in combination with calculation of bending characteristics and torsion angle characteristics, which is excellent in convenience. Yes.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Therefore, all such modifications are included in the scope of the present invention. For example, in the above description, the exercise tool in which the center of gravity of the head 13c is deviated from the long axis of the shaft 13a as in the golf club 13 is described. However, the present invention is not limited thereto, and the center of gravity of the head 13c is the length of the shaft 13a. The present invention can also be applied to an exercise tool along an axis. Further, for example, a term described at least once together with a different term having a broader meaning or the same meaning in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings. Further, the configurations and operations of the arithmetic processing circuit 14, the display device 19, the input device 21, the storage device 16, and the like are not limited to those described in the present embodiment, and various modifications can be made.

  DESCRIPTION OF SYMBOLS 11 Exercise tool behavior analysis apparatus (golf swing analysis apparatus), 12 Inertial sensor, 13 Exercise tool (golf club), 13a Shaft, 14 Computation part (arithmetic processing circuit), 24 Grip end, 25 Head end

Claims (9)

Using the output of the inertial sensor attached to the shaft of the movement device having a shaft connected to the head,
A calculation unit for calculating a concentrated moment acting on both end portions of the shaft during the swing of the exercise tool ;
The output of the inertial sensor includes an acceleration signal that specifies an acceleration generated in the exercise tool,
Of both end portions of the shaft, one end is a grip portion, and the other end is a connecting portion between the shaft and the head,
The computing unit is
Multiplying the mass of the head and the acceleration generated in the head during a swing to calculate the force acting on the head,
Calculating the concentration moment of the grip portion using a force acting on the head and a distance from the grip portion of the shaft to the connecting portion;
A force acting on the head, sporting goods behavior analysis device which is characterized that you calculate the concentration moment of the coupling portion with the distance from the connecting portion of the shaft to the center of gravity of the head. The exercise device behavior analysis apparatus according to claim 1 ,
The output of the inertial sensor, sporting goods behavior analysis device which comprises an angular velocity signal that identifies the angular velocity occurs before Symbol sporting goods. The exercise device behavior analysis apparatus according to claim 2 ,
The acceleration generated on the head side is
Acceleration and angular velocity obtained from the output of the inertial sensor attached to the shaft;
A motion tool behavior analysis apparatus characterized by being estimated using a distance from a position of the shaft to which the inertial sensor is attached to a center of gravity of the head. In the exercise device behavior analysis apparatus according to any one of claims 1 to 3 ,
The motion unit behavior analysis apparatus, wherein the calculation unit calculates a distribution of a bending moment along a longitudinal direction in which the shaft extends using the concentrated moment of the grip portion and the concentrated moment of the connecting portion. . The exercise device behavior analysis apparatus according to claim 4 ,
Before SL calculating unit, based on the bending rigidity distribution of the shaft, sporting goods behavior perpendicular to the long axis direction of the shaft, and wherein the calculating the deflection in the direction along the face of the head Analysis device. The exercise device behavior analysis apparatus according to claim 4 ,
Before SL calculating unit, based on the bending rigidity distribution of the shaft, sporting goods behavior perpendicular to the long axis direction of the shaft, and characterized by calculating a deflection of the direction orthogonal to the face surface of the head Analysis device. In the exercise device behavior analysis apparatus according to any one of claims 1 to 6 ,
The exercise unit behavior analysis apparatus, wherein the calculation unit calculates a torsion around a long axis along which the shaft extends based on a torsional rigidity distribution of the shaft. A step of receiving the output of the inertial sensor attached to the shaft of the movement device having a shaft connected to the head,
Using the output of the inertial sensor, calculating a concentration moment acting on both end portions of the shaft during the swing of the exercise tool;
Equipped with a,
The output of the inertial sensor includes an acceleration signal that specifies an acceleration generated in the exercise tool,
Of both end portions of the shaft, one end is a grip portion, and the other end is a connecting portion between the shaft and the head,
The process includes
Multiplying the mass of the head by the acceleration generated in the head during a swing to calculate a force acting on the head;
Calculating the concentration moment of the grip portion using a force acting on the head and a distance from the grip portion of the shaft to the connecting portion;
Calculating the concentration moment of the connecting portion using the force acting on the head and the distance from the connecting portion of the shaft to the center of gravity of the head;
A motion tool behavior analysis method comprising: Using the output of an inertial sensor attached to the shaft of an exercise tool having a shaft connected to the head, the computer executes a procedure for calculating a concentrated moment acting on both end portions of the exercise tool shaft during the swing of the exercise tool A sports equipment behavior analysis program,
The output of the inertial sensor includes an acceleration signal that specifies an acceleration generated in the exercise tool,
Of both end portions of the shaft, one end is a grip portion, and the other end is a connecting portion between the shaft and the head,
The procedure is as follows:
A procedure for calculating a force acting on the head by multiplying the mass of the head by an acceleration generated in the head during a swing;
Calculating the concentration moment of the grip portion using a force acting on the head and a distance from the grip portion of the shaft to the connecting portion;
Calculating the concentration moment of the connecting portion using the force acting on the head and the distance from the connecting portion of the shaft to the center of gravity of the head;
A sports equipment behavior analysis program comprising:

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