JP7027745B2 - Analysis device for the behavior of hitting tools - Google Patents

Description

The present invention relates to an analyzer, a method and a program for analyzing the behavior of a striking tool swung by a user.

Conventionally, a technique for analyzing the behavior of a striking tool swung by a user has been known (see, for example, Non-Patent Document 1). Non-Patent Document 1 discloses a technique for simulating bending deformation during a swing of each minute element constituting a shaft of a golf club according to an analysis model based on the finite element method.

Kenta Matsumoto, 5 others, "Effects of club head inertia on shaft behavior", Proceedings of Sports Engineering / Human Dynamics 2015, B-34 (USB memory), October 2015

By the way, in the mode in which the user uses the hitting tool, characteristics peculiar to the user appear. For example, when thinking about golf clubs, some users have a strong grip, while others do not. Also, where to grip the grip depends on the user, and some grip it shallowly (grasp near the grip end) and others grip it deeply (grasp the position away from the grip end toward the head). And these characteristics when the user uses the hitting tool can affect the behavior of the hitting tool during the swing. Therefore, it is important to identify the characteristics when the user uses the hitting tool.

It is an object of the present invention to provide an analyzer, a method and a program capable of specifying the characteristics when a user uses a hitting tool.

The analysis device according to the first aspect is an analysis device that analyzes the behavior of the hitting tool swung by the user, and is the first to acquire the first measurement data that measures the behavior of the hitting tool from the first measuring instrument. The first swing is based on the acquisition unit, the second acquisition unit that acquires the second measurement data that measures the behavior of the hitting tool from the second measuring instrument, and the second measurement data during the first swing. Based on the specific part that specifies the predetermined behavior of the hitting tool and the first measurement data during the first swing, the characteristics when the user uses the hitting tool are analyzed as parameters. According to the model, the analysis unit that analyzes the deformation of the hitting tool during the first swing and the analysis result by the analysis unit match the predetermined behavior specified by the specific unit. It is provided with a determination unit that determines analysis parameters.

The analysis device according to the second aspect is the analysis device according to the first aspect, and the analysis parameters are the strength of the gripping force at which the user grips the hitting tool, and the analysis device during the swing by the user. At least one of the centers of rotation in the hitting tool.

The analysis device according to the third aspect is the analysis device according to the second aspect, and the analysis unit corrects the first measurement data based on the rotation center, and obtains the corrected first measurement data. Based on this, the deformation of the hitting tool is analyzed.

The analysis device according to the fourth aspect is the analysis device according to the second aspect or the third aspect, and the analysis unit models the grip included in the hitting tool with a spring model and analyzes the deformation of the hitting tool. do. The determination unit determines the spring constant of the spring model as the strength of the gripping force.

The analysis device according to the fifth viewpoint is an analysis device according to any one of the first to fourth viewpoints, and the determination unit is based on the analysis result by the analysis unit, and the first swing is used. The analysis parameter is determined by specifying the predetermined behavior and optimizing the analysis parameter so that the predetermined behavior matches or approaches the predetermined behavior specified by the specific unit.

The analysis device according to the sixth viewpoint is an analysis device according to any one of the first to fifth viewpoints, and the analysis unit is determined by the first measurement data and the determination unit during the second swing. Based on the analysis parameters, the deformation of the hitting tool during the second swing is further analyzed.

The analysis device according to the seventh viewpoint is an analysis device according to any one of the first to sixth viewpoints, and the predetermined behavior includes the speed, angle, and traveling direction of a predetermined portion included in the hitting tool. At least one of is included.

The analysis device according to the eighth viewpoint is an analysis device according to any one of the first to seventh viewpoints, and the hitting tool is a golf club.

The analysis device according to the ninth aspect is the analysis device according to the eighth aspect, and the predetermined behavior includes at least one of a head speed, a face angle, a trajectory angle, and a blow angle.

The analysis device according to the tenth viewpoint is the analysis device according to the eighth viewpoint or the ninth viewpoint, and the first measuring instrument is configured to measure the behavior of the grip included in the hitting tool. The second measuring instrument is configured to measure the behavior of the head included in the striking tool.

The analysis device according to the eleventh viewpoint is an analysis device according to any one of the first to tenth viewpoints, and the first measuring instrument includes an inertial sensor.

The analysis device according to the twelfth viewpoint is the analysis device according to the eleventh viewpoint, and the first aspect is such that the analysis result by the analysis unit matches the predetermined behavior specified by the specific unit. A correction parameter for removing the bias component of the angular velocity included in the first measurement data during the swing is calculated, and a correction unit for correcting the angular velocity is further provided based on the correction parameter. The analysis unit analyzes the deformation of the hitting tool based on the first measurement data including the corrected angular velocity.

The analysis program according to the thirteenth aspect is an analysis program for analyzing the behavior of the striking tool swung by the user, and causes the computer to execute the following steps.
-Step to acquire the first measurement data measuring the behavior of the hitting tool from the first measuring instrument-Step to acquire the second measurement data measuring the behavior of the hitting tool from the second measuring instrument-During the first swing Step to specify a predetermined behavior of the hitting tool resulting from the first swing based on the second measurement data of the user.-The user based on the first measurement data during the first swing. Steps to analyze the deformation of the hitting tool during the first swing according to the model whose analysis parameter is the feature when the hitting tool is used. The analysis result of the deformation is based on the second measurement data. Steps to determine the analysis parameters to match a given behavior

The analysis method according to the fourteenth aspect is an analysis method for analyzing the behavior of a striking tool swung by the user, and includes the following steps.
-Step to acquire the first measurement data measuring the behavior of the hitting tool from the first measuring instrument-Step to acquire the second measurement data measuring the behavior of the hitting tool from the second measuring instrument-During the first swing Step to specify a predetermined behavior of the hitting tool resulting from the first swing based on the second measurement data of the user.-The user based on the first measurement data during the first swing. Steps to analyze the deformation of the hitting tool during the first swing according to the model whose analysis parameter is the feature when the hitting tool is used. The analysis result of the deformation is based on the second measurement data. Steps to determine the analysis parameters to match a given behavior

According to the present invention, the behavior of the hitting tool is measured separately by the first measuring instrument and the second measuring instrument. Further, based on the first measurement data during the swing measured by the first measuring instrument, the deformation of the hitting tool during the swing is analyzed according to the model whose analysis parameter is the feature when the user uses the hitting tool. To. Further, from the second measurement data during the swing measured by the second measuring instrument, a predetermined behavior of the hitting tool generated as a result of the swing is specified. Then, the analysis parameters are determined so that the analysis result of the deformation of the hitting tool matches the predetermined behavior based on the second measurement data. From the above, it is possible to analyze the characteristics when the user uses the hitting tool.

The side view of the swing analysis system including the analysis apparatus which concerns on one Embodiment of this invention. Front view of the swing analysis system. Top view of the swing analysis system. A functional block diagram showing the configuration of a swing analysis system. A perspective view of a golf club illustrating the xyz local coordinate system. The figure which shows the position of the marker attached to a head. A flowchart showing the flow of analysis processing for the swing of the first shot. A flowchart showing the flow of analysis processing for the swing after the second shot. The figure explaining the rotation center in a hitting tool. Graph of the locus of the grip end based on the sensor data before and after the correction based on the center of rotation in the hitting tool. The figure explaining the analysis model of the deformation of the shaft according to the finite element method. A graph that conceptually shows the relationship between the true value of the angular velocity and the value measured by the angular velocity sensor. A flowchart showing a process for calculating a threshold value which is a correction parameter for removing a bias component. The figure which shows the position of the marker attached to the head of the golf club which concerns on Reference Example and Examples 1 and 2. The figure which shows the analysis result of the head speed which concerns on Reference Example and Example 1. FIG. The figure which shows the analysis result of the face angle which concerns on Reference Example and Example 1. FIG. The figure which shows the analysis result of the orbital angle which concerns on Reference Example and Example 1. FIG. The figure which shows the analysis result of the blow angle which concerns on Reference Example and Example 1. FIG.

Hereinafter, an analysis device, a method, and a program according to an embodiment of the present invention will be described with reference to the drawings.

<1. Overview of swing analysis system>
1 to 4 show an overall configuration diagram of a swing analysis system 100 including an analysis device 1 according to an embodiment of the present invention. The swing analysis system 100 is a system that analyzes the behavior of the golf club 5 swung by the golfer G. The behavior of the golf club 5 is measured by each of the first measuring instrument MD1 and the second measuring instrument MD2. The first measuring instrument MD1 and the second measuring instrument MD2 together with the analysis device 1 constitute a swing analysis system 100.

A portion of the golf club 5, particularly the shaft 52, has the property of being deformed during a swing. The analysis device 1 of the shaft 52 of the golf club 5 during the swing is based on the measurement data (first measurement data) indicating the behavior of the grip end 51a of the golf club 5 during the swing measured by the first measuring instrument MD1. Analyze the deformation. At this time, the deformation of the shaft 52 is analyzed according to a model in which a feature peculiar to the golfer G when the golfer G uses the golf club 5 is used as an analysis parameter. In the present embodiment, the strength of the gripping force that the golfer G grips the golf club 5 during the swing and the rotation center C of the golf club 5 during the swing are used as analysis parameters. Further, the analysis device 1 identifies a predetermined behavior of the golf club 5 generated as a result of the swing based on the measurement data (second measurement data) measured by the second measuring instrument MD2. The predetermined behavior referred to here is, for example, the position, speed, angle, traveling direction, etc. of a predetermined portion included in the golf club 5. Subsequently, the analysis device 1 determines the above-mentioned analysis parameters so that the analysis result of the deformation of the shaft 52 based on the first measuring instrument MD1 matches the predetermined behavior of the golf club 5 based on the second measuring instrument MD2. (Optimize). This makes it possible to identify the characteristics when the golfer G uses the golf club 5. Further, the finally determined analysis parameter is used for the analysis of the deformation of the shaft 52 during the subsequent swing by the same golfer G.

Hereinafter, the configuration of the first measuring instrument MD1, the second measuring instrument MD2, and the analysis device 1 will be described, and then the flow of the analysis process will be described.

<2. Details of each part>
The first measuring instrument MD1 according to the present embodiment is composed of the following inertial sensor unit 40 and two distance image sensors 2A and 2B. On the other hand, the second measuring instrument MD2 according to the present embodiment is composed of a high-performance photographing system. Hereinafter, they will be described in order.

<2-1. 1st measuring instrument>
<2-1-1. Inertia sensor unit>
As shown in FIG. 1, the inertial sensor unit 40 is attached to the grip end 51a, which is an end of the grip 51 of the golf club 5 opposite to the head 53, and measures the behavior of the grip end 51a. As shown in FIG. 5, the golf club 5 is a general golf club, and is composed of a shaft 52, a head 53 provided at one end of the shaft 52, and a grip 51 provided at the other end of the shaft 52. To. The inertial sensor unit 40 is compact and lightweight so as not to interfere with the swing operation.

As shown in FIG. 4, the inertial sensor unit 40 according to the present embodiment is equipped with an acceleration sensor 41, an angular velocity sensor 42, and a geomagnetic sensor 43. Further, the inertial sensor unit 40 is also equipped with a communication device 44 for transmitting sensor data output from these sensors 41 to 43 to an external device such as the analysis device 1 via the communication line 17. .. In the present embodiment, the communication device 44 is wireless so as not to interfere with the swing operation, but may be connected to the analysis device 1 by wire via a cable. The sensor data is transmitted from the sensors 41 to 43 to the analysis device 1 in real time via the communication device 44. However, for example, the sensor data may be stored in the storage device in the inertial sensor unit 40, and the sensor data may be taken out from the storage device after the swing operation is completed and passed to the analysis device 1.

The acceleration sensor 41, the angular velocity sensor 42, and the geomagnetic sensor 43 measure acceleration, angular velocity, and geomagnetism in the xyz local coordinate system, respectively. More specifically, the acceleration sensor 41 measures the accelerations a _x , a _y , and a _z of the grip end 51a in the x-axis, y-axis, and z-axis directions. The angular velocity sensor 42 measures the angular velocities ω _x , ω _y , and ω _z of the grip end 51a around the x-axis, y-axis, and z-axis. The geomagnetic sensor 43 measures the geomagnetisms _{mx, my, and m z in} the _x -axis, y-axis, and z-axis directions at the grip end 51a. The sensor data (first measurement data) relating to these accelerations, angular velocities and geomagnetism are acquired as time-series data having a predetermined short sampling period.

The xyz local coordinate system is a 3-axis Cartesian coordinate system defined as shown in FIG. That is, the z-axis coincides with the extending direction of the shaft 52, and the direction from the head 53 to the grip 51 is the z-axis positive direction. The y-axis is oriented so as to be as close as possible to the flying ball direction at the time of addressing the golf club 5, that is, substantially along the face-back direction, and the direction from the back side to the face side is the positive y-axis direction. .. The x-axis is oriented so as to be orthogonal to the y-axis and the z-axis, that is, substantially along the toe-heel direction, and the direction from the heel side to the toe side is the x-axis positive direction. The origin of the xyz local coordinate system is the grip end 51a.

Further, in addition to the xyz local coordinate system, the XYZ inertial coordinate system, which is the three-axis Cartesian coordinate system shown in FIGS. 1 to 3, is also defined. The Z-axis is the direction from the vertical lower side to the upper side, the X-axis is the direction from the back of the golfer G to the belly, and the Y-axis is the direction parallel to the ground plane from the hitting point of the ball 55 to the target point. Is.

The golf swing generally proceeds in the order of address, top, impact, and finish. The address means a stationary state in which the head 53 is arranged near the ball 55, and the top means a state in which the golf club 5 is taken back from the address and the head 53 is swung up most. The impact means a state at the moment when the golf club 5 is swung down from the top and the head 53 collides with the ball 55, and the finish means a state where the golf club 5 is swung forward after the impact.

<2-1-2. Distance image sensor>
The distance image sensors 2A and 2B are cameras having a distance measuring function of measuring the distance to the subject while taking a two-dimensional image of the golfer G trying to hit the golf club 5. Therefore, the distance image sensors 2A and 2B can output a time-series depth image together with a time-series two-dimensional image. The two-dimensional image referred to here is an image obtained by projecting an image of the shooting space into a plane orthogonal to the optical axis of the camera. The depth image is an image in which the depth data of the subject in the optical axis direction of the camera is assigned to pixels within the same imaging range as the two-dimensional image. In the present embodiment, as shown in FIG. 1, the first distance image sensor 2A is installed in front of the golfer G so as to capture the golf swing from the front side of the golfer G. On the other hand, the second distance image sensor 2B is installed on the right side of the golfer G in order to shoot the golf swing from a direction different from that of the distance image sensor 2A, specifically, to shoot the golfer G from the right side. ..

As shown in FIG. 4, both distance image sensors 2A and 2B have the same configuration. Therefore, in the following, for the sake of simplicity, the configuration of the distance image sensor 2A will be described, but the same applies to the distance image sensor 2B. The analysis device 1 may be composed of a plurality of computers, and for example, the distance image sensors 2A and 2B may be connected to different computers.

The distance image sensor 2A used in the present embodiment captures a two-dimensional image as an infrared image (hereinafter referred to as an IR image). Further, the depth image can be obtained by a method such as a time-of-flight method using infrared rays or a dot pattern projection method. Therefore, as shown in FIG. 1, the distance image sensor 2A has an IR light emitting unit 21 that emits infrared rays toward the front and an IR that receives infrared rays that are emitted from the IR light emitting unit 21 and reflected on the subject and returned. It has a light receiving unit 22. The IR light receiving unit 22 is a camera having an optical system, an image pickup device, and the like. In the present embodiment, the IR light emitting unit 21 and the IR light receiving unit 22 are housed in the same housing 20 and are arranged in front of the housing 20.

In the distance image sensor 2A, in addition to the CPU 23 that controls the entire operation of the distance image sensor 2A, a memory 24 that at least temporarily stores image data (first measurement data) of captured time-series IR images and depth images. Is installed. The control program that controls the operation of the distance image sensor 2A is stored in the memory 24. Further, the distance image sensor 2A also has a built-in communication unit 25, and the communication unit 25 transmits the captured image data to an external device such as an analysis device 1 via a wired or wireless communication line 17. Can be output to. In the present embodiment, the CPU 23 and the memory 24 are also housed in the housing 20 together with the IR light emitting unit 21 and the IR light receiving unit 22. It should be noted that the transfer of image data to the analysis device 1 does not necessarily have to be performed via the communication unit 25. For example, if the memory 24 is removable, the image data can be read out by the analysis device 1 by removing it from the housing 20 and inserting it into the reader of the analysis device 1 (corresponding to the communication unit 15 described later). Can be done.

In the present embodiment, as described above, infrared imaging is performed by the distance image sensor 2A, and the behavior of the grip end 51a is analyzed based on the captured IR image. Therefore, although omitted in FIG. 5, a reflective sheet that efficiently reflects infrared rays is used as a marker on the grip end 51a so that the behavior of the grip end 51a can be easily measured by the distance image sensors 2A and 2B. It is affixed. A similar infrared reflective sheet is also attached to the shaft 52 as a marker.

<2-2. 2nd measuring instrument>
The detailed configuration of the second measuring instrument MD2 is shown in FIGS. 2 and 3. In addition, in FIG. 1, the second measuring instrument MD2 is omitted, whereas in FIGS. 2 and 3, the first measuring instrument MD1 is omitted. The second measuring instrument MD2 is a high-performance photographing system equipped with a plurality of cameras 3A to 3H, and time-series image data obtained by measuring the behavior of the head 53 during a swing from various directions by these cameras 3A to 3H. (Second measurement data) is photographed. The cameras 3A to 3H are strobe type. Therefore, the second measuring instrument MD2 further includes strobes 4A to 4H that illuminate the shooting range of the cameras 3A to 3H, and also includes a trigger device 8 that determines the timing of operation of the cameras 3A to 3H and the strobes 4A to 4H.

The cameras 3A to 3H photograph the state in the vicinity of the head 53 in the vicinity of the impact. That is, the behavior of the head 53 near the impact is photographed from a plurality of directions by a plurality of cameras 3A to 3H. Therefore, the behavior of the head 53 is three-dimensionally captured by a plurality of series of image data output from the plurality of cameras 3A to 3H. By image processing these image data, the analysis device 1 can calculate the behavior of the head 53 as a result of the swing of the golf club 5 with high accuracy. In the present embodiment, the head speed, face angle, blow angle, and trajectory angle immediately before impact are calculated as the behavior of the head 53.

The cameras 3A to 3H are arranged above the golfer G, such as being hung on the ceiling. Of these, the cameras 3A to 3D are arranged in the immediate vicinity of the golfer G, and the cameras 3E to 3H are arranged slightly separated from each other on the positive side in the Y-axis direction with respect to the golfer G. The cameras 3A to 3H are connected to the analysis device 1 via a wired or wireless communication line 18. The image data taken by the cameras 3A to 3H is transmitted to the analysis device 1 in real time. It is also possible to store the image data in the storage device built in the cameras 3A to 3H and later transfer the image data from the storage device to the analysis device 1.

The strobes 4A to 4H are light emitting devices that assist the shooting of the cameras 3A to 3H. The strobes 4A to 4H are also placed above the golfer G, such as being hung on the ceiling. Of these, the strobes 4A to 4E are arranged in the immediate vicinity of the golfer G, and the strobes 4F to 4H are arranged slightly apart on the positive side in the Y-axis direction with respect to the golfer G. The strobes 4A to 4H operate in synchronization with the cameras 3A to 3H.

As shown in FIG. 6, a plurality of markers M1 to M5 are attached to the head 53. The markers M1 to M5 efficiently reflect the light emitted from the strobes 4A to 4H, and are attached so that the positions of the markers M1 to M5 and the behavior of the head 53 can be easily captured by the cameras 3A to 3H. The markers M1 to M4 are attached to the face surface 53a that hits the ball 55 in the head 53, and preferably, a region near the center on the face surface 53a so as not to interfere with the hitting of the ball 55 on the face surface 53a. It is attached avoiding. The marker M5 is attached so as to extend elongated along the vicinity of the center of the upper edge of the face surface 53a on the top surface of the head 53. The positions where the markers M1 to M5 are attached here are examples.

The trigger device 8 includes a plurality of sets of timing sensors and a timing control device 9. More specifically, the floodlight 6A and the light receiver 7A, the floodlight 6B and the light receiver 7B, and the floodlight 6C and the light receiver 7C each constitute a set of timing sensors. The floodlights 6A to 6C and the light receivers 7A to 7C are arranged near the feet of the golfer G. The timing control device 9 is connected to the cameras 3A to 3H, the strobes 4A to 4H, and the analysis device 1 in addition to the floodlights 6A to 6C and the light receivers 7A to 7C.

The floodlight and the light receiver included in each timing sensor are arranged on a straight line substantially parallel to the X-axis and face each other (see FIG. 3). During the swing, the floodlights 6A to 6C constantly irradiate the light receivers 7A to 7C, respectively, and the light receivers 7A to 7C receive the light. However, at the timing when the golf club 5 passes between the floodlights 6A to 6C and the receivers 7A to 7C, the light from the floodlights 6A to 6C is blocked by the golf club 5, so that the receivers 7A to 7C do this. Cannot receive light. The light receivers 7A to 7C each detect this timing, and based on this timing, generate a timing for the timing control device 9 to operate the cameras 3A to 3H and the strobes 4A to 4H. The timing signal generated by the timing control device 9 is transmitted from the timing control device 9 to the cameras 3A to 3H and the strobes 4A to 4H. In response to this, these cameras 3A to 3H and strobes 4A to 4H perform photographing and light emission.

<2-3. Analyst>
The analysis device 1 is a general-purpose computer as hardware, and is realized as, for example, a tablet computer, a smartphone, a notebook computer, or a desktop computer. As shown in FIG. 4, the analysis device 1 is manufactured by installing the analysis program 31 from a computer-readable recording medium 30 such as a CD-ROM into a general-purpose computer. The analysis program 31 is software for analyzing the golf swing based on the first and second measurement data sent from the first and second measuring instruments MD1 and MD2, respectively, and is an operation described later in the analysis device 1. To execute.

The analysis device 1 includes a display unit 11, an input unit 12, a storage unit 13, a control unit 14, and a communication unit 15. These units 11 to 15 are connected to each other via the bus line 16 and can communicate with each other. The display unit 11 can be configured with a liquid crystal display or the like, and displays the result of golf swing analysis or the like to the user. The term "user" as used herein is a general term for golfers G themselves, their instructors, developers of golf equipment, and other persons who require the results of golf swing analysis. The input unit 12 can be composed of a mouse, a keyboard, a touch panel, or the like, and receives an operation from the user on the analysis device 1.

The storage unit 13 can be configured by a hard disk or the like. In addition to storing the analysis program 31, the storage unit 13 also stores the first and second measurement data sent from the first and second measuring instruments MD1 and MD2. The control unit 14 can be composed of a CPU, a ROM, a RAM, and the like. By reading and executing the analysis program 31 in the storage unit 13, the control unit 14 virtually reads out and executes the first acquisition unit 14a, the second acquisition unit 14b, the analysis unit 14c, the specific unit 14d, the determination unit 14e, and the correction unit. It operates as 14f. Details of the operation of each part 14a to 14f will be described later. The communication unit 15 functions as a communication interface for receiving data from external devices including the inertial sensor unit 40, the distance image sensors 2A and 2B, and the cameras 3A to 3H via the communication lines 17 and 18.

<3. Analysis method>
Hereinafter, an analysis method for analyzing the behavior of the golf club 5 during a swing will be described. In this analysis method, the deformation of the shaft 52 is analyzed, and the predetermined behavior of the head 53 generated as a result of the swing is derived. At this time, the characteristics when the golfer G swings the golf club 5 are taken into consideration. Specifically, in the process of analyzing the deformation of the shaft 52, a characteristic peculiar to the golfer G when the golfer G swings the golf club 5 is determined and used as an analysis parameter. Further, since the same golfer G is considered to have the same characteristics, the above-mentioned analysis parameters are diverted to the subsequent analysis of the golf swing performed by the same golfer G. Therefore, different analysis processes are performed for the first golf swing by the same golfer G and the subsequent golf swings. The analysis process corresponding to the former is shown in FIG. 7, and the analysis process corresponding to the latter is shown in FIG. 8, which will be described in order below. Since the process of FIG. 8 is similar to the process of FIG. 7, the process of FIG. 8 will be described focusing on the differences from the process of FIG. 7.

<3-1.1 Golf swing analysis processing for the first shot>
First, the golfer G swings the golf club 5 with the inertial sensor unit 40 described above. In step S1, at this time, the inertial sensor unit 40 included in the first measuring instrument MD1 causes accelerations a _x , a _y , a _z , angular velocities ω _x , ω _y , ω _z and geomagnetic m _x , m during the golf swing. Sensor data (first measurement data) of _y and m _z are detected. Further, these sensor data are transmitted to the analysis device 1 via the communication device 44 of the inertial sensor unit 40. On the other hand, on the analysis device 1 side, the first acquisition unit 14a receives this via the communication unit 15 and stores it in the storage unit 13. In this embodiment, time-series sensor data is collected at each time during the swing, including at least a section from just before the address to the finish.

Further, in step S2, the swing motion of the golf club 5 is photographed by the distance image sensors 2A and 2B included in the first measuring instrument MD1. That is, the distance image sensors 2A and 2B detect image data (first measurement data) that captures the golf swing. Step S2 is performed in parallel with step S1 for the same swing operation as step S1. The detected image data is transmitted to the analysis device 1 via the communication unit 25 of the distance image sensors 2A and 2B. On the other hand, on the analysis device 1 side, the first acquisition unit 14a receives this via the communication unit 15 and stores it in the storage unit 13. In this embodiment, time-series image data at each time during the swing is collected.

Further, in step S3, the swing motion of the golf club 5 is photographed by the second measuring instrument MD2. That is, the cameras 3A to 3H detect the image data (second measurement data) that captures the golf swing. Step S3 is performed in parallel with steps S1 and S2 for the same swing operation as steps S1 and S2. The detected image data is transmitted from the cameras 3A to 3H to the analysis device 1. On the other hand, on the analysis device 1 side, the second acquisition unit 14b receives this via the communication unit 15 and stores it in the storage unit 13. In this embodiment, time-series image data at each time during the swing is collected.

In the following step S4, the analysis unit 14c corrects the first measurement data at each time during the swing. This correction is made by considering the center of rotation C in the golf club 5 during the swing by the golfer G. In many cases, the golfer G swings the golf club 5 by grasping the vicinity of the end portion of the golf club 5, as shown in FIG. Therefore, conventionally, in the simulation model for analyzing the behavior of the golf club 5 during the swing, it is assumed that the golf club 5 rotates about the grip end 51a. However, in reality, the rotation center C of the golf club 5 is not the grip end 51a, but is often in the vicinity of the gripping position exactly held by the player in the golf club 5. Conventionally, the true center of rotation of such a golf club 5 has not been considered, but grasping this can contribute to a more accurate simulation. The gripping position on the grip 51 is peculiar to the golfer G, and is used as an analysis parameter representing the characteristics when the golfer G swings the golf club 5.

Specifically, in step S4, the analysis unit 14c sets a value of a specific rotation center C, and corrects the sensor data acquired in step S1 based on the rotation center C. As shown in FIG. 7, steps S4 to S9 are repeatedly executed until the rotation center C peculiar to the golfer G is finally determined (step S11), whereby the optimum solution of the rotation center C is determined. .. Therefore, in step S4, the value of the rotation center C is appropriately selected according to the algorithm of the optimization method adopted. The value (initial value) of the rotation center C set in the first step S4 may be estimated from the sensor data before correction, or is 0 which means that the rotation center coincides with the grip end 51a. Including the case of).

In the present embodiment, the first measurement data to be corrected in step S4 is the sensor data of the accelerations a _x , a _y , and a _z at each time during the swing. Since the position of the inertial sensor unit 40 is offset from the center of rotation C by a distance d _h at the accelerations a _x , a _y , and _az at the grip end 51a measured by the inertial sensor unit 40, the position around the center of rotation C is offset. Contains rotating components. This rotation component is generated by the influence of the angular velocity and the angular acceleration generated at the position of the inertial sensor unit 40 with the rotation around the rotation center C. The analysis unit 14c calculates this rotation component based on the rotation center C, and removes this from a _s = (ax, a _y , a _z ), so that the corrected acceleration a _s'at the grip end _51a = (A _x ', a _y ', a _z ') sensor data is calculated. This rotation component can be expressed as ([ω _{s_T} ] [ω _{s_T} ] + [ω _{s_T} ']) {h}. Note that ω _{s_T} is a tensor (antisymmetric tensor representing the outer product) of ω _s = (ω _x , ω _y , ω _z ), and ω _{s_T'is} a derivative of ω _{s_T} . Further, h = (0, 0, d _h ).

FIG. 10 is a graph of the locus of the grip end derived by the simulation actually performed by the present inventors. More specifically, the golf swing is performed by converting the time-series data of the acceleration as in the _xyz local coordinate system into the value in the XYZ inertial coordinate system and then integrating the time-series data of the converted acceleration twice. Time-series data representing the position of the grip end inside was calculated. The graph of "before correction" in FIG. 10 is a graph of the locus of the grip end derived from the time series data of acceleration a _s and angular velocity ω _s without correction based on the rotation center C, and is "after correction". The graph of is a graph of the locus of the grip end derived from the time-series data of the corrected acceleration a _s'and the angular velocity ω _s based on the rotation center C. In calculating the corrected graph, when the rotation center C was calculated, d _h = 19.15 cm. As you can see by comparing these graphs, the graph before correction is jagged, and noise that seems to be due to angular velocity and angular acceleration is confirmed in the graph, but such noise is confirmed from the graph after correction. Can be seen to have been removed.

In the following step S5, the time series sensor data corrected in step S4 and the time series image data acquired in step S2 are time-adjusted. In other words, the analysis unit 14c synchronizes the sensor data (unless otherwise specified, it means the latest corrected sensor data; the same applies hereinafter) and the image data.

Specifically, first, the analysis unit 14c derives the address, top and impact times based on the sensor data. Since various methods for deriving these times are known, detailed description thereof will be omitted here.

Subsequently, the analysis unit 14c derives the posture matrix N at each time during the swing based on the sensor data. Now, the posture matrix N is expressed by the following equation. The attitude matrix N is a matrix for converting the value of the xyz local coordinate system into the value of the XYZ inertial coordinate system.

The meanings of the nine components of the attitude matrix N are as follows.
Component a: Cosine of the angle between the X-axis of the inertial coordinate system and the x-axis of the local coordinate system Component b: Cosine of the angle between the Y-axis of the inertial coordinate system and the x-axis of the local coordinate system Component c: Inertia Cosine component of the angle formed by the Z axis of the coordinate system and the x axis of the local coordinate system d: Cosine component of the angle formed by the X axis of the inertial coordinate system and the y axis of the local coordinate system e: Y of the inertial coordinate system Cosine component of the angle between the axis and the y-axis of the local coordinate system f: Cosine component of the angle between the Z-axis of the inertial coordinate system and the y-axis of the local coordinate system g: X-axis of the inertial coordinate system and local Cosine component of the angle formed by the z-axis of the coordinate system h: Cosine component of the angle formed by the Y-axis of the inertial coordinate system and the z-axis of the local coordinate system i: Z-axis of the inertial coordinate system and z of the local coordinate system Cosine of the angle formed by the axis Here, the vector (a, b, c) represents the unit vector in the x-axis direction, and the vector (d, e, f) represents the unit vector in the y-axis direction, and the vector ( g, h, i) represent a unit vector in the z-axis direction.

Since various methods for calculating the attitude matrix N based on the sensor data output from the inertial sensor unit are known, detailed description thereof will be omitted here. If necessary, the methods described in JP-A-2016-2429, JP-A-2016-2430, etc. by the same applicants can be followed.

Subsequently, the analysis unit 14c detects an image of the linear shaft 52 at each time by performing image processing on the image data (hereinafter referred to as front image data) at each time during the swing derived from the distance image sensor 2A. Then, the orientation of the shaft 52 in the time series is specified. Further, the direction of the shaft 52 is specified based on the vector (g, h, i) representing the direction of the z-axis, which is specified from the posture matrix N at each time during the swing. Then, the analysis unit 14c aligns both time-series data so that the degree of coincidence between the orientation of the time-series shaft 52 derived from the sensor data and the orientation of the time-series shaft 52 derived from the front image data is the highest. do.

Subsequently, the front image data and the image data taken from the right side by the distance image sensor 2B (hereinafter referred to as the right image data) are synchronized. Specifically, the analysis unit 14c derives the three-dimensional coordinates of the grip end 51a at each time during the swing by performing image processing on the front image data. Similarly, the analysis unit 14c derives the three-dimensional coordinates of the grip end 51a at each time during the swing by performing image processing on the right image data.

Subsequently, the analysis unit 14c has the highest degree of agreement between the three-dimensional coordinates of the time-series grip end 51a derived from the front image data and the three-dimensional coordinates of the time-series grip end 51a derived from the right image data. , Align both time series data. As a result, the time of the right image data and the sensor data are adjusted via the front image data.

In the following step S6, the analysis unit 14c derives the posture of the grip 51 at each time during the swing. The posture of the grip 51 can be represented by the orientation of the xyz local coordinate system described above in the XYZ inertial coordinate system fixed to the ground. Therefore, in the present embodiment, NT ( ^T on the right shoulder represents a transposed matrix), which is a posture matrix for converting the XYZ inertial coordinate system into the xyz local coordinate system, is derived as the posture of the grip 51.

As described in the explanation of step S5, the posture matrix ^NT can be calculated only from the sensor data, but in the present embodiment, the image data acquired in step S2 is also included in order to further improve the accuracy of the analysis. With reference, the attitude matrix ^NT is calculated. That is, both the sensor data acquired in step S1 (sensor data corrected in step S4) and the image data acquired in step S2 capture the same operation of the golf club 5. Therefore, using the sensor data in step S4 and the image data in step S2, a predetermined objective function including the attitude matrix ^NT is defined, and the attitude matrix ^NT is used as an optimum solution for minimizing or maximizing the objective function. Can be derived.

In the following step S7, the analysis unit 14c accelerates the grip 51 (more accurately, the grip end 51a) in the xyz local coordinate system at each time during the swing, and the grip 51 (more accurately, the grip 51) in the xyz local coordinate system. The angular velocity and the angular acceleration of the grip end 51a) are calculated. Specifically, the acceleration of the grip 51 in the xyz local coordinate system is derived by canceling the gravity component from the value of the acceleration included in the sensor data. The angular velocity of the grip 51 in the xyz local coordinate system corresponds to the value of the angular velocity included in the sensor data. The angular acceleration of the grip 51 in the xyz local coordinate system is calculated by differentiating the value of the angular velocity included in the sensor data.

As described above, the values of the acceleration, the angular velocity, and the angular acceleration of the grip 51 in the xyz local coordinate system can be calculated only from the sensor data. However, in the present embodiment, in order to further improve the accuracy of the analysis, the values of the acceleration, the angular velocity, and the angular acceleration of the grip 51 are also referred to with reference to the image data acquired in step S2 as in the case of the attitude matrix ^NT . Is optimized.

In the following step S8, the analysis unit 14c analyzes the deformation of the shaft 52 at each time during the swing. The deformation analysis model of the shaft 52 according to the present embodiment is a model according to the finite element method. The grip 51 and shaft 52 are assumed to be multi-stage cylindrical beam elements, and the head 53 is assumed to be rigid. As shown in FIG. 11, the grip 51 and the shaft 52 are each divided into a plurality of minute elements along the longitudinal direction. In the present embodiment, the grip 51 and the element closest to the grip 51 in the shaft 52 are defined as a physical region, and the remaining region is defined as an elastic deformation region.

Further, although the grip 51 is gripped by the golfer G, it is not gripped as hard as a fixed end, but is gripped so as to move with a flexible hand movement. Therefore, in this analysis model, in order to express such a flexible gripping condition, as shown in FIG. 11, the grip 51 is modeled by a spring model, and the deformation of the shaft 52 is analyzed. In the spring model, the above gripping condition is expressed by the spring constant of the element corresponding to the grip 51. The spring constant represents the strength of the gripping force at which the golfer G grips the grip 51, and represents the characteristics when the golfer G swings the golf club 5. Further, in general, the strength of the gripping force is not constant during the swing period, is relatively small from the address to the top, and is relatively large during the downswing after the top. Therefore, in this spring model, it is assumed that the spring constant is a constant value from the address to the top and linearly increases from the top to the impact. Therefore, in this spring model, the spring constants are the components ka _x , kay, ka _z in the x, y and z directions at the time of address (more specifically, from the address to the top) and x, y and _z at the time of impact. It is represented by the directional components ki _x , ki _y , and ki _z . The spring constants ka _x , ka _y , ka _z , ki _x , ki _y , and ki _z are the analysis parameters of this analysis model.

In step S8, the analysis unit 14c sets the spring constants ka _x , ka _y , ka _z , ki _x , ki _y , ki _z , and the spring constants ka _x , ka _y , ka _z , ki _x , ki _y , Ki _z is input to the analysis model of the deformation of the shaft 52 described above. As described above, in step S8, the strength of the gripping force peculiar to the golfer G, that is, the optimum solution of the spring constants ka _x , ka _y , ka _z , ki _x , ki _y , ki _z is determined (step). It is repeatedly executed up to S11). Therefore, in step S8, the values of the spring constants ka _x , ka _y , ka _z , ki _x , ki _y , and ki _z are appropriately selected according to the algorithm of the optimization method adopted. The values (initial values) of the spring constants ka _x , ka _y , ka _z , ki _x , ki _y , and ki _z set in the first step S8 may be estimated from the sensor data before correction, or may be predetermined. It may be a value. Further, the analysis unit 14c has, as parameters representing the behavior of the grip 51, the posture of the grip 51 at each time during the swing calculated in steps S6 and S7, and the acceleration, angular velocity and angular acceleration of the grip 51 in the xyz local coordinate system. Is input to the analysis model of the deformation of the shaft 52 described above. As a result, the amount of deformation of each element of the grip 51 and the shaft 52 is calculated.

The basic concept of the analysis model of the deformation of the shaft 52 according to the present embodiment is also shown in Non-Patent Document 1. Therefore, this analysis model can be understood in more detail by referring to Non-Patent Document 1.

In the following step S9, the determination unit 14e determines the predetermined behavior of the golf club 5 resulting from the swing (hereinafter, the first result value) based on the deformation amount of each element of the grip 51 and the shaft 52 calculated in step S8. ) Is specified. The first result value in the present embodiment relates to the behavior of the head 53, and more specifically, the head speed HS _Sim immediately before the impact, the face angle FA _Sim , the blow angle BA _Sim , and the orbit angle PATH _Sim . ..

At the time of executing step S9, the amount of deformation of each element of the golf club 5 at each time during the swing is derived by the steps so far. Therefore, the determination unit 14e derives the behavior of the element on the most head 53 side (hereinafter referred to as the final element) on the shaft 52 at each time during the swing based on this information. Then, from the behavior of this final element and the data of the shape of the head 53, the positions of various points of interest (including the center of gravity of the head 53) of the head 53 at each time during the swing are calculated. The data of the shape of the head 53 is, for example, CAD data at the time of designing the head 53, and is assumed to be stored in advance in the storage unit 13. Then, the determination unit 14e derives the behavior of the head 53 as described above based on the positions of various points of interest of the head 53 in these time series.

Further, step S10 is executed in parallel with steps S4 to S9. In step S10, the specific unit 14d has the same predetermined behavior of the golf club 5 as in step S9 (hereinafter, the second result value) based on the second measurement data from the second measuring instrument MD2 acquired in step S3. ) Is specified. That is, here, as the second result value, the head speed HS _Mot , the face angle FA _Mot , the blow angle BA _Mot , and the orbital angle PATH _Mot immediately before the impact, which are derived from the measurement result of the highly accurate second measuring instrument MD2, are specified. Will be done. Specifically, by performing image processing on the image data at each time during the swing acquired in step S3, the images of the markers M1 to M5 are detected, and the positions and orientations of the detected images of the markers M1 to M5 are determined. Based on this, the second result value is calculated.

In the following step S11, the determination unit 14e determines the analysis parameters regarding the rotation center C and the strength of the gripping force based on the first result value and the second result value. In the present embodiment, the optimum solution of the analysis parameter is specified by optimizing the analysis parameter so that the first result value matches or approaches the second result value. That is, the second result value, which is the measurement result of the second measuring instrument MD2 having high-precision analysis performance, is extremely close to the true value, and by matching or bringing the first result value to or close to this, the rotation center C and gripping are performed. The optimum solution of force strength can be obtained.

Specifically, the determination unit 14e defines the following objective function J, and determines the strength of the rotation center C and the gripping force so that the objective function J is minimized as the optimum solutions for each. Therefore, the determination unit 14e substitutes the first result value calculated in the immediately preceding step S9 and the second result value calculated in the step S10 into the following equation, and these values are predetermined close to 0. Judge whether it converges to a value within the range (hereinafter referred to as the end condition). Then, when the end condition is satisfied, the optimization process is terminated, and the latest rotation center C and the strength of the gripping force are determined as the strength of the rotation center C and the gripping force peculiar to the golfer G. On the other hand, if the end condition is not satisfied, the process returns to step S4.

In the following step S12, the correction unit 14f corrects the first measurement data at each time during the swing acquired in step S1, more specifically, the sensor data of the angular velocities ω _x , ω _y , and ω _z . This correction is made by considering the bias components of the angular velocities ω _x , ω _y , and ω _z . That is, in general, the output value of the angular velocity sensor 42 (gyro sensor) includes a bias component as an error. In particular, since the golf club 5 moves at high speed immediately before the impact, which roughly corresponds to the downswing period, the bias component becomes large. Therefore, by removing such a bias component, it becomes possible to simulate a golf swing with higher accuracy.

FIG. 12 is a graph conceptually showing the relationship between the angular velocity ω _i , which is the measured value of the angular velocity sensor 42, and its true value (i = x, y, z). As shown in the figure, the measured value of the angular velocity ω _i and the true value have a linear relationship when the magnitude of the angular velocity ω _i is small, but have a linear relationship when the magnitude of the angular velocity ω _i is large. It collapses. As a result, the bias component becomes large in the high speed region (ω _i > TH _i ) of the angular velocity ω _i and becomes small in the low speed region (ω _i <−TH _i ) of the angular velocity ω _i . Therefore, in the present embodiment, the angular velocity ω _i is corrected according to the following correction formula. Note that ω _i'is the corrected angular velocity (angular velocity including the bias component), TH _i is a threshold value that determines the range in which the linear relationship between the true value and the measured value is maintained, and k _i is. It is a correction coefficient. In the following formula, the absolute values of the upper and lower threshold values are the same, but they can be set differently.
ω _i '= TH _i + (ω _i -TH _i ) x k _i (when ω _i > TH _i )
ω _i '=-TH _i + (ω _i + TH _i ) x k _i (when ω _i <-TH _i )

TH _i and k _i are correction parameters for removing the bias component of the angular velocity ω _i . In the present embodiment, the threshold value TH _i is set based on the sensor data acquired in step S1 and the second measurement data from the second measuring instrument MD2 acquired in step S3. Specifically, the correction unit 14f is a threshold value such that the head speed HS _Sim and the face angle FA _Sim calculated in step S9 match or approach the head speed HS _Mot and the face angle FA _Mot calculated in step S10. Calculate TH _i . Then, the correction unit 14f corrects the sensor data of the angular velocities ω _x , ω _y , and ω _z at each time during the swing according to the above correction formula based on the threshold value TH _i .

FIG. 13 is a flowchart showing a process for calculating the threshold value TH _i included in step S12. The algorithm of this process is based on the following findings obtained by the present inventors through experiments. That is, when a golf club with an inertial sensor such as the golf club 5 was swung many times by various subjects and the swing data at that time was analyzed, when the threshold value TH _x was increased, the head speed HS _Sim became faster. The face angle FA _Sim tended to close more. Further, when the threshold value TH _y was increased, the head speed HS _Sim became slower and the face angle FA _Sim tended to open more. Further, when the threshold value TH _z was increased, the head speed HS _Sim became slower and the face angle FA _Sim tended to open more. This relationship is summarized in Table 1.

Based on the above findings, the correction unit 14f determines whether the head speed HS _Sim is faster than the head speed HS _Mot by the first value or more (step S21). If it is fast, the process proceeds to step S22, and the threshold values TH _x and TH _z are set to predetermined values (for example, 0 rad / s and 1 rad / s, respectively) so that the head speed HS _Sim matches or approaches the head speed HS _Mot , respectively. Set. Further, in step S22, a threshold value TH _y is set so that the head speed HS _Sim matches or approaches the head speed HS _Mot by using the dichotomy method.

Further, the correction unit 14f determines whether the head speed HS _Sim is faster than the head speed HS _Mot by a second value or more, which is smaller than the first value (step S23). If it is fast, the process proceeds to step S24, and the threshold values TH _x , TH _y , and TH _z are set to predetermined values (for example, 0.5 rad / s, respectively) so that the head speed HS _Sim matches or approaches the head speed HS _Mot . Set to 0 rad / s, 1 rad / s).

Further, the correction unit 14f determines whether the head speed HS _Sim is slower than the head speed HS _Mot by a third value or more (step S25). If it is slow, the process proceeds to step S26, and the threshold values TH _y and TH _z are set to predetermined values (for example, 0 rad / s and 1 rad / s, respectively) so that the head speed HS _Sim matches or approaches the head speed HS _Mot , respectively. Set. Further, in step S26, a threshold value TH _x is set so that the head speed HS _Sim matches or approaches the head speed HS _Mot by using the dichotomy method.

After the adjustment of the head speed is completed in steps S21 to S26, the face angle is adjusted next (steps S27 and S28). After adjusting the head speed, the face angle may be adjusted. In step S27, the correction unit 14f determines whether the face angle FA _Sim is separated from the face angle FA _Mot by a predetermined value or more. If they are far apart, the process proceeds to step S28, and the dichotomy is used to set a threshold TH _z such that the face angle FA _Sim matches or approaches the face angle FA _Mot .

After that, in step S13, the analysis unit 14c determines the sensor data of the angular velocities ω _x ', ω _y ', ω _z'after the correction by step S12, and the rotation center C and the strength of the gripping force determined in step S11. Using the optimum solution, the same processing as in steps S4 to S9 is performed again. That is, the deformation of the shaft 52 is re-analyzed, and the first result value including the head speed HS _Sim , the face angle FA _Sim , the blow angle BA _Sim , and the trajectory angle PATH _Sim is recalculated.

In the following step S14, the result of step S13 is displayed on the display unit 11. For example, the values of the head speed HS _Sim , the face angle FA _Sim , the blow angle BA _Sim , and the trajectory angle PATH _Sim included in the first result value calculated in step S13 are displayed, and instead of or in addition to this, the swing. The deformation of the grip 51 and the shaft 52 inside is displayed graphically. As a result, the analysis process of the first golf swing is completed.

<3-2-2 Analysis processing of golf swing after the second shot>
Next, the analysis process of the golf swing after the second shot will be described with reference to FIG. In the analysis process after the second stroke, the values of the analysis parameter and the correction parameter determined in the first stroke are diverted, the deformation of the shaft 52 is analyzed, and the first result value is calculated. Therefore, in the analysis process after the second shot, the first measurement data from the first measuring instrument MD1 is collected (steps S1 and S2) as in the case of the first shot, but as in step S3 described above. Collection of the second measurement data from the second measuring instrument MD2 is omitted.

After steps S1 and S2, the analysis unit 14c removes the bias component from the sensor data of the angular velocities ω _x , ω _y , and ω _z according to the correction formula of step S12 using the threshold value TH _i of the first shot (step). S15). After that, the analysis unit 14c uses the sensor data of the corrected angular velocities ω _x ', ω _y ', and ω _z ', and the optimum solution of the rotation center C of the first shot and the strength of the gripping force, from step S4 to The same processing as in S9 and S14 is performed. As a result, the deformation of the shaft 52 after the second shot is analyzed, and the first result value including the head speed HS _Sim , the face angle FA _Sim , the blow angle BA _Sim , and the trajectory angle PATH _Sim is calculated, and further, these The analysis result is displayed on the display unit 11.

<4. Modification example>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the following changes are possible. In addition, the gist of the following modifications can be combined as appropriate.

<4-1>
The analysis device, method and program according to the above embodiment are configured to be suitable for analyzing the behavior of a golf club, but a similar algorithm is used to analyze the behavior of any swinging tool. Can be used.

<4-2>
The above-mentioned configurations of the first measuring instrument MD1 and the second measuring instrument MD2 are examples, and the first measuring instrument MD1 and the second measuring instrument MD2 can be variously configured. For example, the first measuring instrument MD1 may be composed of only one distance image sensor 2A and the inertial sensor unit 40, may be composed of only the inertial sensor unit 40, or may be composed of one or a plurality of distance images. It can also be composed of only sensors. Further, the geomagnetic sensor 43 can be omitted from the inertial sensor unit 40.

Further, the second measuring instrument MD2 can be a high-performance motion capture system composed of a plurality of cameras. However, the second measurement data from the second measuring instrument MD2 is higher than the first measuring instrument MD1 because it is used to determine the correction parameters of the first measurement data and the analysis parameters representing the characteristics of the golfer G. It is preferable that the device can accurately measure the behavior of the golf club 5.

<4-3>
The predetermined behavior of the golf club 5 specified in steps S9, S10 and the like is not limited to the above-mentioned examples of the head speed, face angle, blow angle and trajectory angle, and even if various other behaviors of the head 53 are specified. Alternatively, various behaviors of various parts other than the head 53 may be specified. Also, the predetermined behavior used to determine the analysis parameters does not have to be plural, but may be one. For example, the analysis parameters can be determined so that only the head velocity based on the first measurement data matches the index based on the second measurement data.

<4-4>
In the above embodiment, the analysis parameter is determined based only on the result of the first stroke, but the analysis parameter may be determined based on the result of the plurality of strokes. In this case as well, the same analysis parameter can be used for the subsequent analysis of the shaft 52. The same applies to the correction parameters.

<4-5>
In the above embodiment, the rotation center C and the strength of the gripping force are used as the analysis parameters representing the characteristics when the golfer G swings the golf club 5, but only one of these can be used. Further, as analysis parameters, various features when the golfer G swings the golf club 5 can be used as analysis parameters in addition to the rotation center C and the strength of the gripping force.

<4-6>
In the above embodiment, the deformation of the shaft 52 is analyzed based on the rotation center C and the strength of the gripping force, and then the correction for removing the bias component is performed, but both steps can be executed in the reverse order. ..

<Reference example (true value)>
As shown in FIG. 14, a golf club having markers attached to the positions near the face surface on the crown portion of the head, near the end portion on the toe side and near the end portion on the heel side, was prepared. Then, the trajectory of these markers during a swing using this golf club was measured by a motion capture system that enables high-precision three-dimensional measurement consisting of a plurality of cameras. Then, from the trajectories of the above markers, the head velocity, face angle, orbital angle and blow angle immediately before impact were calculated.

<Example 1>
By the same process as the analysis process of FIG. 7 according to the above embodiment, the deformation of the shaft is analyzed in consideration of the strength of the gripping force of the rotation center C and the golfer during the swing, and based on the result, immediately before the impact. The head speed, face angle, trajectory angle and blow angle were calculated. However, here, the correction for removing the bias component in step S12 is omitted. Further, in the first embodiment, as the first measurement data derived from the first measuring instrument, the acceleration data and the angular velocity data of the grip portion derived from the motion capture system, and the image data derived from the distance image sensor are used, and the second measurement is performed. A motion capture system was also used as a vessel.

<Example 2>
By the same process as the analysis process of FIG. 7 according to the above embodiment, the strength of the gripping force of the rotation center C and the golfer during the swing is taken into consideration, and the deformation of the shaft is analyzed by making a correction to remove the bias component. Based on the results, the head speed, face angle, trajectory angle and blow angle immediately before impact were calculated. However, in Example 2, a motion capture system was used as the second measuring instrument.

<Verification>
15A to 15D are graphs showing the correlation between the head speed, the face angle, the trajectory angle, and the blow angle immediately before the impact according to the reference example and the first embodiment, respectively. As can be seen from the figure, the error of Example 1 with respect to the reference example was about ± 1.5 m / s for the head speed and about ± 1.5 deg for the face angle, the trajectory angle and the blow angle, which were very small. From this result, the effect of the algorithm according to the first embodiment was confirmed.

Table 2 below shows the head speed, face angle, track angle, and blow angle according to the reference example and the second embodiment. As can be seen from the table, the error of the examples with respect to the reference example was very small. From this result, the effect of the algorithm according to the second embodiment was confirmed.

1 Analytical device 14a 1st acquisition unit 14b 2nd acquisition unit 14c Analysis unit 14d Specific unit 14e Determination unit 14f Correction unit 2A Distance image sensor 2B Distance image sensor 3A to 3H Camera 40 Inertivity sensor unit 5 Golf club 51 Grip 52 Shaft 53 Head MD1 1st measuring instrument MD2 2nd measuring instrument G golfer

Claims (14)

It is an analysis device that analyzes the behavior of a striking tool that is swung by the user.
The first acquisition unit that acquires the first measurement data that measures the behavior of the hitting tool from the first measuring instrument, and
A second acquisition unit that acquires the second measurement data that measures the behavior of the hitting tool from the second measuring instrument, and
Based on the second measurement data during the first swing, a specific part that specifies a predetermined behavior of the hitting tool that occurs as a result of the first swing, and a specific unit.
Based on the first measurement data during the first swing, the deformation of the hitting tool during the first swing is performed according to a model in which the characteristics when the user uses the hitting tool are used as analysis parameters. The analysis unit to analyze and
An analysis device including a determination unit that determines the analysis parameters so that the analysis result by the analysis unit matches the predetermined behavior specified by the specific unit. The analysis parameters are at least one of the strength of the gripping force at which the user grips the hitting tool and the center of rotation of the hitting tool during the swing by the user.
The analysis device according to claim 1. The analysis unit corrects the first measurement data based on the center of rotation, and analyzes the deformation of the hitting tool based on the corrected first measurement data.
The analysis device according to claim 2. The analysis unit models the grip included in the hitting tool with a spring model, analyzes the deformation of the hitting tool, and analyzes the deformation of the hitting tool.
The determination unit determines the spring constant of the spring model as the strength of the gripping force.
The analysis device according to claim 2 or 3. The determination unit identifies the predetermined behavior due to the first swing based on the analysis result by the analysis unit, and the predetermined behavior matches the predetermined behavior specified by the identification unit. The analysis parameters are determined by optimizing the analysis parameters so that they are close to each other.
The analysis device according to any one of claims 1 to 4. The analysis unit further analyzes the deformation of the hitting tool during the second swing based on the first measurement data during the second swing and the analysis parameters determined by the determination unit.
The analysis device according to any one of claims 1 to 5. The predetermined behavior includes at least one of a velocity, an angle and a traveling direction of a predetermined portion included in the hitting tool.
The analysis device according to any one of claims 1 to 6. The hitting tool is a golf club.
The analysis device according to any one of claims 1 to 7. The predetermined behavior includes at least one of head speed, face angle, trajectory angle and blow angle.
The analysis device according to claim 8. The first measuring instrument is configured to measure the behavior of the grip included in the striking tool.
The second measuring instrument is configured to measure the behavior of the head included in the striking tool.
The analyzer according to claim 8 or 9. The first measuring instrument includes an inertia sensor.
The analysis device according to any one of claims 1 to 10. To remove the bias component of the angular velocity included in the first measurement data during the first swing so that the analysis result by the analysis unit matches the predetermined behavior specified by the specific unit. A correction unit for calculating the correction parameter and correcting the angular velocity based on the correction parameter is further provided.
The analysis unit analyzes the deformation of the hitting tool based on the first measurement data including the corrected angular velocity.
The analysis device according to claim 11. An analysis program that analyzes the behavior of hitting tools that are swung by the user.
The step of acquiring the first measurement data that measures the behavior of the hitting tool from the first measuring instrument, and
The step of acquiring the second measurement data that measures the behavior of the hitting tool from the second measuring instrument, and
A step of identifying a predetermined behavior of the hitting tool resulting from the first swing based on the second measurement data during the first swing.
Based on the first measurement data during the first swing, the deformation of the hitting tool during the first swing is performed according to a model in which the characteristics when the user uses the hitting tool are used as analysis parameters. Steps to analyze and
A computer is made to perform a step of determining the analysis parameters so that the analysis result of the deformation matches the predetermined behavior based on the second measurement data.
Analysis program. An analysis method for analyzing the behavior of a striking tool swung by a user, the step comprising a step performed by a computer.
The step of acquiring the first measurement data that measures the behavior of the hitting tool from the first measuring instrument, and
The step of acquiring the second measurement data that measures the behavior of the hitting tool from the second measuring instrument, and
A step of identifying a predetermined behavior of the hitting tool resulting from the first swing based on the second measurement data during the first swing.
Based on the first measurement data during the first swing, the deformation of the hitting tool during the first swing is performed according to a model in which the characteristics when the user uses the hitting tool are used as analysis parameters. Steps to analyze and
An analysis method including a step of determining the analysis parameters so that the analysis result of the deformation matches the predetermined behavior based on the second measurement data.

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