Ball driving analysis device and ball driving analysis method
The combination of infrared sensors and cameras in a coordinated control system addresses false detections and inefficiencies in existing ball launch analysis, providing accurate flight parameter calculation.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- GPRO CO LTD
- Filing Date
- 2025-09-17
- Publication Date
- 2026-07-16
AI Technical Summary
Existing ball launch analysis technologies using infrared sensors and cameras are prone to false detections due to external noise and inefficiencies in capturing the moment of launch, requiring high-cost continuous shooting and inefficient data processing.
A ball launch analysis device combining left and right infrared sensors with cameras to detect and capture the ball's placement, appearance, and disappearance, using a coordinated control system to transmit trigger signals for accurate flight parameter calculation.
Enables highly accurate analysis of ball flight parameters by minimizing false detections and optimizing data capture, reducing costs and inefficiencies in existing systems.
Smart Images

Figure JP2025032797_16072026_PF_FP_ABST
Abstract
Description
Ball launch analysis device and ball launch analysis method
[0001] The present invention relates to a ball launch analysis device and a ball launch analysis method.
[0002] Conventionally, there are many technologies related to devices for analyzing the results of hitting a golf ball or other ball with a club. For example, Japanese Patent Publication No. 2005-529339 (Patent Document 1) discloses a method for determining the parameters of a moving golf ball. Japanese Patent Publication No. 2015-512660 (Patent Document 2) discloses a device for measuring a golf club head having a club face. Japanese Patent Publication No. 2019-536064 (Patent Document 3) discloses a golf ball launch monitor used in conjunction with an alignment stick. Japanese Patent Application Publication No. 2020-071228 (Patent Document 4) discloses a method for calculating the motion trajectory of an object. Japanese Patent Application Publication No. 2020-078069 (Patent Document 5) discloses a method for assisting in the filming of a golf swing. Japanese Patent Application Publication No. 2020-095019 (Patent Document 6) discloses a method for measuring the rotation of a ball. Japanese Patent Publication No. 2021-507426 (Patent Document 7) discloses a ball tracking system comprising a display, a sensor, a launch monitor, and a processor. Japanese Patent Publication No. 2022-520507 (Patent Document 8) discloses a method for measuring physical quantities related to a golf club. Japanese Patent Publication No. 2022-520681 (Patent Document 9) discloses a method for measuring the rotation of a ball. Japanese Patent Publication No. 2023-548132 (Patent Document 10) discloses a method for supporting a virtual golf simulation.
[0003] Furthermore, Japanese Patent Publication No. 2000-66315 (Patent Document 11) discloses a method for scientifically measuring the behavior of a club, which has a deep causal relationship with the motion of the launched ball. Japanese Patent Publication No. 2013-153802 (Patent Document 12) discloses a golf club measuring device that reduces measurement errors and is highly convenient. Japanese Patent Publication No. 2012-52845 (Patent Document 13) discloses a measuring device that more accurately measures the speed of both the striking tool and the ball being struck.
[0004] On the other hand, the applicant of the present application has applied for and obtained patent rights for the inventions disclosed in the following patent documents. For example, Japanese Patent Application Laid-Open No. 2017-169950 (Patent Document 14) discloses a ball missile detection device and a ball missile detection method for detecting a ball missile. Japanese Patent Application Laid-Open No. 2018-205074 (Patent Document 12) discloses a flight parameter measurement device and a flight parameter measurement method. Japanese Patent Application Laid-Open No. 2021-071387 (Patent Document 13) discloses a ball tracking device and a ball tracking method.
[0005] Japanese Patent Application Laid-Open No. 2005-529339, Japanese Patent Application Laid-Open No. 2015-512660, Japanese Patent Application Laid-Open No. 2019-536064, Japanese Patent Application Laid-Open No. 2020-071228, Japanese Patent Application Laid-Open No. 2020-078069, Japanese Patent Application Laid-Open No. 2020-095019, Japanese Patent Application Laid-Open No. Tokuhei 2021-507426, Japanese Patent Application Laid-Open No. Tokuhei 2022-520507, Japanese Patent Application Laid-Open No. Tokuhei 2022-520681, Japanese Patent Application Laid-Open No. Tokuhei 2023-548132, Japanese Patent Application Laid-Open No. 2000-66315, Japanese Patent Application Laid-Open No. 2013-153802, Japanese Patent Application Laid-Open No. 2012-52845, Japanese Patent Application Laid-Open No. 2017-169950, Japanese Patent Application Laid-Open No. 2018-205074, Japanese Patent Application Laid-Open No. 2021-071387
[0006] In recent years, devices such as infrared sensors and cameras have become easily available, and the development of devices that can accurately perform the analysis of the flight parameters of a ball from the player's hitting of the ball to the use of these devices has been underway.
[0007] While infrared sensors can accurately detect the appearance of the club and the disappearance of the ball at the moment of launch, they are susceptible to external noise and prone to false detections. On the other hand, cameras, due to their wide field of view, can accurately capture the ball's position, but to capture the moment of launch, the camera must continuously capture images from the moment the ball is placed. Furthermore, to properly capture the moment of launch, a high-performance camera capable of high-speed continuous shooting is required, which is costly. In addition, continuous shooting by the camera requires a huge amount of data, and although the camera should ideally continuously capture the moment of launch, to capture that moment, the camera must also continuously capture the player's practice swings, which is inefficient.
[0008] Here, the technologies described in the aforementioned Patent Documents 1-12 and 15-16 are technologies using cameras and have the same problems as described above. Also, Patent Document 14 is a technology using an infrared sensor and has the same problems as described above. Furthermore, Patent Document 13 uses a Doppler sensor, but as described above, a Doppler sensor needs to continuously monitor the scene even when the player is practicing, and has the same problems.
[0009] Therefore, the present invention has been made to solve the aforementioned problems, and aims to provide a ball launch analysis device and a ball launch analysis method that can perform highly accurate analysis from the launch of a ball to the analysis of the flight parameters of the ball by appropriately combining an infrared sensor and a camera.
[0010] The ball launch analysis device according to the present invention comprises left and right infrared sensors, left and right cameras, a placement determination control unit, an appearance determination control unit, a disappearance determination control unit, a next appearance determination control unit, a signal transmission control unit, an image capture control unit, and a calculation control unit. The left and right infrared sensors are provided on the left and right sides of the device, and are capable of detecting the left detection area and the right detection area, respectively, and the left detection area and the right detection area are adjacent to each other and do not overlap. The left and right cameras are provided on the left and right sides of the device, and are capable of capturing the left image capture area and the right image capture area, respectively, which include the left detection area and the right detection area, and the left image capture area and the right image capture area overlap to each other. The placement determination control unit uses the left and right cameras to determine whether the ball is placed in either the left trigger area, which is pre-set within the left detection area, or the right trigger area, which is pre-set within the left detection area, within the right image capture area. If the appearance determination control unit determines that the ball has been placed in either the left trigger area or the right trigger area, it uses an infrared sensor corresponding to the camera in the installation trigger area where the ball was placed to determine whether an object has appeared in the installation detection area, including the installation trigger area. If the appearance determination control unit determines that an object has appeared in the installation detection area, it uses an infrared sensor corresponding to the installation detection area to determine whether the ball has disappeared from the installation detection area. If the disappearance determination control unit determines that the ball has disappeared from the installation detection area, it uses an infrared sensor corresponding to the launch detection area adjacent to the installation detection area to determine whether the ball has appeared in the launch detection area. If the next appearance determination control unit determines that the ball has appeared in the launch detection area, it transmits a trigger signal. When the trigger signal is transmitted, the shooting control unit uses the left and right cameras to continuously photograph the ball in the left shooting area and the right shooting area. The calculation control unit calculates the flight parameters of the ball based on the ball images taken in succession by the left and right cameras.
[0011] Furthermore, the ball launch analysis method according to the present invention is a ball launch analysis method for a ball launch analysis device equipped with left and right infrared sensors and left and right cameras, and each control step of the ball launch analysis method according to the present invention corresponds to each control unit of the ball launch analysis device according to the present invention.
[0012] According to the present invention, by appropriately combining an infrared sensor and a camera, it becomes possible to perform highly accurate analysis of the ball's flight parameters, from launching the ball to analyzing its flight parameters.
[0013] Figure 1A is a schematic diagram showing an example of a player swinging with the ball launch analysis device according to the present invention, and Figure 1B is a schematic diagram showing an example of a player swinging with the ball launch analysis device according to the present invention. Figure 1B is a schematic diagram showing an example of a specific configuration of the ball launch analysis device according to the present invention. Figure 2 is a functional block diagram of the ball launch analysis device according to the present invention. Figure 3 is a flowchart showing the execution procedure of the ball launch analysis device according to the present invention. Figure 5A is a schematic diagram showing an example of when the left and right cameras of the ball launch analysis device according to the present invention are activated, and Figure 5B is a diagram showing an example of when the ball image is identified using the left and right images captured by the left and right cameras. Figure 6A is a schematic diagram showing an example of when a player places the ball in the tee area with the ball launch analysis device according to the present invention, and Figure 6B is a diagram showing an example of when the ball image enters the right trigger area in the right image. Figure 7A shows an example of a conceptual diagram illustrating the relationship between the camera coordinate system and the world coordinate system, along with a captured image in which a ball launch prediction area is set. Figure 7B shows a schematic diagram illustrating an example of the ball launch analysis device according to the present invention when infrared detection is activated. Figure 8A shows an example of the ball launch analysis device according to the present invention before the club appears in the right detection area, and Figure 8B shows an example of the ball launch analysis device according to the present invention when the club appears in the right detection area. Figure 9A shows a schematic diagram illustrating an example of the ball launch analysis device according to the present invention when the player takes a practice swing, and Figure 9B shows an example of the ball disappearing from the right detection area. Figure 10A shows a schematic diagram illustrating an example of the ball not flying in the launch direction, and Figure 10B shows an example of the ball flying forward in the launch direction. Figure 11A shows a schematic diagram illustrating an example of a ball launch analysis device according to the present invention in which continuous shooting is performed by transmitting a trigger signal, and Figure 11B shows a schematic diagram illustrating an example in which the ball is photographed with the right camera at the first time point and the ball is photographed with the left camera at the second time point.Figure 12A shows an example of calculating flight parameters from ball speed to side angle from ball images taken at two different times, and Figure 12B shows an example of calculating backspin and sidespin flight parameters from ball images taken at two different times. Figure 13A shows an example of acquiring images taken at two different times with the same camera, and Figure 13B shows an example of calculating flight parameters using the ball launch prediction region to identify the first ball image at the first time and the center coordinates of the ball in the world coordinate system at the time of installation. This figure shows an example of when flight parameters and a swing video are displayed in the ball launch analysis device according to the present invention. This figure shows an example of when the ball launch prediction region is set at the time of installation, and an image taken when the ball launch prediction region is set at the time of installation in the embodiment, with the ball captured by the right camera at the first time, the ball captured by the left camera at the second time. This figure shows an example of images taken by the left and right cameras at the time of installation, an image taken by the right camera at the first time, and an image taken by the left camera at the second time in the embodiment.
[0014] The embodiments of the present invention will be described below with reference to the attached drawings to facilitate understanding of the invention. Note that the following embodiments are merely examples of the present invention and are not intended to limit the technical scope of the invention.
[0015] As shown in Figure 1A, the ball launch analysis device 1 according to the present invention is installed on a flat batting cage S. When power is turned on, it activates left and right infrared sensors and left and right cameras to form their respective regions Z (detection region, shooting region). When a player P (user) places a ball B (for example, a golf ball) in region Z, the ball launch analysis device 1 determines whether or not the ball B has been placed in a preset trigger region within region Z.
[0016] Next, when ball B is placed in the trigger area, the ball launch analysis device 1 may, for example, display a message indicating readiness (e.g., "READY") on the display unit D (monitor unit), or display ball images of ball B taken by the left and right cameras.
[0017] Then, as shown in Figure 1B, when player P hits ball B with club C, the ball launch analysis device 1 detects the period from the appearance of club C to the disappearance of ball B in region Z and emits a trigger signal indicating that ball B has been launched.
[0018] Furthermore, the ball launch analysis device 1, upon transmission of a trigger signal, analyzes the ball images of ball B captured by the left and right cameras to calculate the flight parameters of ball B (e.g., carry, ball speed, launch angle, side angle, backspin, sidespin, etc.), and displays the calculated flight parameters on the display unit D.
[0019] Next, the specific configuration of the ball launch analysis device 1 will be described. First, as shown in Figure 2, the ball launch analysis device 1 is equipped with left and right infrared sensors (left infrared sensor 10a, right infrared sensor 10b) and left and right cameras (left camera 11a, right camera 11b).
[0020] Here, the left and right infrared sensors 10a and 10b are provided on the left and right sides of the device 1, respectively, and are capable of detecting the left detection area Z10a and the right detection area Z10b, respectively. The left detection area Z10a and the right detection area Z10b are adjacent to each other and do not overlap. As shown in Figure 2, the left infrared sensor 10a is installed on the lower left side of the device 1, and the right infrared sensor 10b is installed on the lower right side of the device 1. The left detection area Z10a of the left infrared sensor 10a and the right detection area Z10b of the right infrared sensor 10b are configured in a predetermined shape (for example, rectangular) and are adjacent to each other and do not overlap. The left and right infrared sensors 10a and 10b detect the appearance of ball B in either the right detection area Z10a or the left detection area Z10b, the appearance of club C (object), and the disappearance of ball B based on the change in the intensity of the reflected light in the right detection area Z10a and the left detection area Z10b, respectively.
[0021] Furthermore, there are no particular limitations on the configuration of the left and right infrared sensors 10a and 10b. For example, as shown in Figure 2, rectangular slits are provided on the left and right sides of the ball launch analysis device 1, and LEDs (light-emitting elements) that use infrared light as a light source are provided inside the left and right slits. The infrared light emitted by the LEDs passes through the slits of a predetermined shape (for example, rectangular), and the left detection area Z10a and the right detection area Z10b are configured in the aforementioned shape (for example, rectangular). As a result, by providing slits on the left and right, the left detection area Z10a and the right detection area Z10b take on a predetermined shape as a whole, and the detection area Z is configured in the batting cage S.
[0022] Furthermore, although the width in the launch direction between the left detection area Z10a and the right detection area Z10b is set as appropriate, for example, if a ball B is placed in either the left detection area Z10a or the right detection area Z10b, the sizes of the left detection area Z10a and the right detection area Z10b are set so that the ball B is present only in either the left detection area Z10a or the right detection area Z10b.
[0023] Here, the ball launch analysis device 1 has holes directly below the left and right slits, and a photodiode (light-receiving element) that receives reflected infrared light is installed inside the hole to detect the intensity of the reflected light in the left detection area Z10a and the right detection area Z10b. When a ball B is placed in either the left detection area Z10a or the right detection area Z10b, the ball launch analysis device 1 enters an infrared detection state, and the photodiode detects the intensity of the reflected light in the left detection area Z10a and the right detection area Z10b through the hole.
[0024] Furthermore, the left and right cameras 11a and 11b are provided on the left and right sides of the device 1, respectively. The left camera 11a is installed on the upper left side of the device 1, and the right camera 11b is installed on the upper right side of the device 1. The left and right cameras 11a and 11b are capable of capturing the left shooting area Z11a and the right shooting area Z11b, respectively, which include the left detection area Z10a and the right detection area Z10b, and the left shooting area Z11a and the right shooting area Z11b overlap with each other. Here, since the left and right cameras 11a and 11b have a certain field of view, the left shooting area Z11a of the left camera 11a includes the left detection area Z10a and the right detection area Z10b, and the left shooting area Z11b of the right camera 11b includes the left detection area Z10a and the right detection area Z10b. For example, since the field of view of the left and right cameras 11a and 11b is triangular, the left shooting area Z11a of the left camera 11a and the right shooting area Z11b of the right camera 11b both include the left detection area Z10a and the right detection area Z10b, and also partially overlap.
[0025] As shown in Figure 2, when player P hits ball B from right to left towards the ball launch analysis device 1, the area in front of the batting cage S in the launch direction is to the left, and the area behind the batting cage S in the launch direction is to the right. In this case, the left infrared sensor 10a and the left camera 11a first detect and photograph player P's launch, and the right infrared sensor 10b and the right camera 11b detect and photograph player P's launch later. On the other hand, when player P hits ball B from left to right towards the ball launch analysis device 1, the area in front of the batting cage S in the launch direction is to the right, and the area behind the batting cage S in the launch direction is to the left. In this case, the right infrared sensor 10b and the right camera 11b first detect and photograph player P's launch, and the left infrared sensor 10a and the left camera 11a detect and photograph player P's launch later.
[0026] Incidentally, the left shooting area Z11a of the left camera 11a is pre-set as a left trigger area Ta where ball B is placed within the left detection area Z10a of the corresponding left infrared sensor 10a, and the right shooting area Z11b of the right camera 11b is pre-set as a right trigger area Tb where ball B is placed within the left detection area Z10b of the corresponding right infrared sensor 10b. The ball launch analysis device 1 determines whether or not ball B is placed in either the left trigger area Ta or the right trigger area Tb.
[0027] Furthermore, a tee area TE on which a ball B can be placed is pre-installed in the batting cage S, and the ball launch analysis device 1 is installed by the player P so that either the left trigger area Ta or the right trigger area Tb overlaps with the tee area TE of the batting cage S. Here, as shown in Figure 2, the ball launch analysis device 1 is installed so, for example, that the right trigger area Tb of the right shooting area Z11b of the right camera 11b overlaps with the tee area TE.
[0028] Incidentally, the ball launch analysis device 1 has a swing camera 12 installed near the upper center of the device. The swing camera 12 captures the swing region SR that overlaps with the left shooting region Z11a of the left camera 11a and the right shooting region Z11b of the right camera 11a. This makes it possible to capture the swing of player P.
[0029] Furthermore, the ball launch analysis device 1 is equipped with left and right lights La and Lb, which can be illuminated in various colors, installed on the upper left and right sides of the device. In addition, the ball launch analysis device 1 is equipped with a monitor D, which can display various messages, ball images, analysis results, etc., installed above the device.
[0030] The ball launch analysis device 1 includes a power supply unit, a control circuit, and a communication circuit. The power supply circuit supplies power to each circuit, the left and right infrared sensors 10a and 10b, the left and right cameras 11a and 11b, the swing camera 12, the left and right lights La and Lb, and the monitor D, etc. The control circuit incorporates, for example, a CPU, ROM, RAM, etc. (not shown). The CPU, for example, uses RAM as a working area and executes programs stored in ROM, etc. Furthermore, each control unit, which will be described later, is realized by the CPU executing programs. The communication circuit communicates with the player P's terminal device or mobile terminal device, transmitting the analysis results of the ball launch analysis device 1 and receiving information from the player P's terminal device or mobile terminal device.
[0031] Next, with reference to Figures 3-14, the configuration and execution procedure of an embodiment of the present invention will be described. First, when player P turns on the power to the ball launch analysis device 1 (Figure 4: S101), the ball launch analysis device 1 performs a predetermined process, and the display control unit 101 of the ball launch analysis device 1 activates the left and right cameras 11a and 11b (Figure 4: S102). Specifically, as shown in Figure 5A, the display control unit 101 enables the left shooting area Z11a to be photographed with the left camera 11a, and enables the right shooting area Z11b to be photographed with the right camera 11b.
[0032] Next, the display control unit 101 starts displaying on monitor D (Figure 4: S103). Specifically, as shown in Figure 5A, the display control unit 101 displays a message indicating the detection status (for example, "DETECTING") on monitor D. This allows the player P to be informed of the detection status. Note that if there is no information to display on monitor D or if monitor D does not exist at this point, the display control unit 101 may omit the display in S103.
[0033] Next, the lighting control unit 102 of the ball launch analysis device 1 starts lighting up the left and right lights La and Lb (Figure 4: S104). Specifically, as shown in Figure 5A, the lighting control unit 102 lights up the left and right lights La and Lb in a color that indicates the detection state (for example, red). This allows the player P to be notified of the detection state. If the left and right lights La and Lb are not present, the lighting control unit 102 may omit the display in S104.
[0034] Next, when the display control unit 101 activates the left and right cameras 11a and 11b, the installation determination control unit 103 uses the left and right cameras 11a and 11b to determine whether or not the ball B is installed in either the left trigger area Ta of the left shooting area Z11a or the left trigger area Tb of the right shooting area Z11b (Figure 4: S105).
[0035] Here, there are no particular limitations on the determination method of the installation determination control unit 103, but for example, as shown in Figure 5B, when the installation determination control unit 103 acquires the captured image 511a of the left shooting area Z11a captured by the left camera 11a and the captured image 511b of the right shooting area Z11b captured by the right camera 11b, it searches whether or not there is a ball image corresponding to ball B in the captured image 511a of the left shooting area Z11a and the captured image 511b of the right shooting area Z11b.
[0036] Here, there are no particular limitations on the search method of the installation determination control unit 103, but for example, the installation determination control unit 103 performs predetermined image processing (for example, binarization) on the captured image 511a of the left shooting area Z11a and the captured image 511b of the right shooting area Z11b, and extracts the outer edge (contour) of the object in the captured image 511a of the left shooting area Z11a and the outer edge of the object in the captured image 511b of the right shooting area Z11b. Here, binarization means converting pixels whose pixel value is above a predetermined threshold to "1" (white) and pixels whose pixel value is below the threshold to "0" (black). The threshold is set in advance so that the outer edge of ball B in the captured images 511a and 511b is clear.
[0037] The placement determination control unit 103 then detects the image enclosed by the outer edge of the extracted object as the object image. For example, as shown in Figure 5A, when player P holds the ball B in his right hand H and attempts to place it in the tee area TE, as shown in Figure 5B, the captured image 511a of the left shooting area Z11a extracts the outer edge of the right hand H, the outer edge of the ball B, and the outer edge of the tee area TE, resulting in the extraction of a right hand image 500 enclosed by the outer edge of the right hand H, a ball image 501 enclosed by the outer edge of the ball B, and a tee image 502 enclosed by the outer edge of the tee area TE. Furthermore, since the right shooting area Z11b partially overlaps with the left shooting area Z11a, the captured image 511b of the right shooting area Z11b extracts the right hand image 500, the ball image 501, and the tee image 502.
[0038] Furthermore, the installation determination control unit 103 identifies a circular image that approximates a circle to the detected object image. There are no particular limitations on the method by which the installation determination control unit 103 identifies the circular image, but for example, the installation determination control unit 103 calculates the long side L of the object image 503, calculates the area S1 of a circle 504 with the calculated long side L as its diameter, and then calculates the area S2 inside the outer edge of the object image 503. Then, the installation determination control unit 103 calculates the area ratio S1 / S2 by dividing the area S1 of the circle 504 by the area S2 inside the outer edge of the object image 503. The installation determination control unit 103 calculates the area ratio S1 / S2 for all object images 503 and identifies the object image 503 having the area ratio S1 / S2 closest to 1 (-) as the ball image. For example, as shown in Figure 5B, the area ratio S1 / S2 of the right-hand image 500 is greater than 1, the area ratio S1 / S2 of the tee image 502 is somewhat close to 1, and the area ratio S1 / S2 of the ball image 501 is closest to 1, so the ball image 501 is identified as a circular image.
[0039] If the placement determination control unit 103 is unable to identify the ball image as a circular image, it determines that ball B is not placed in either the left trigger area Ta of the left shooting area Z11a or the left trigger area Tb of the right shooting area Z11b (Figure 4: S105NO). In this case, the placement determination control unit 103 returns to S105 and repeats the determination of whether ball B is placed.
[0040] On the other hand, if the installation determination control unit 103 is able to identify the ball image 501 as a circular image, it then acquires positional information of the trigger region of the shooting area where the ball image 501 of the circular image was identified, and determines whether or not the identified ball image 501 is contained within the trigger region. Here, as shown in Figure 5B, when the ball image 501 is identified as a circular image in the captured image 511a of the left shooting area Z11a, the installation determination control unit 103 acquires positional information of the left trigger region Ta of the left shooting area Z11a (for example, coordinate values of the camera coordinate system indicating the boundary of the left trigger region Ta), and determines whether or not the ball image 501 is contained within the left trigger region Ta based on the positional relationship between the ball image 501 and the left trigger region Ta. Similarly, when the ball image 501 is identified in the right shooting area Z11b, the installation determination control unit 103 acquires the position information of the right trigger area Tb of the right shooting area Z11b (the coordinate values of the camera coordinate system indicating the boundary of the right trigger area Tb), and determines whether or not the ball image 501 is contained within the right trigger area Tb based on the positional relationship between the ball image 501 and the right trigger area Tb.
[0041] If the determination results in the ball image not being contained within the trigger area, for example, as shown in Figure 5B, in the captured image 511a of the left shooting area Z11a, the ball image 501 is outside the left trigger area Ta, and in the captured image 511b of the right shooting area Z11b, the ball image 501 is outside the right trigger area Tb, then the placement determination control unit 103 determines that ball B is not placed in either the left trigger area Ta of the left shooting area Z11a or the left trigger area Tb of the right shooting area Z11b (Figure 4: S105NO). In this case, as described above, the placement determination control unit 103 returns to S105 and repeats the determination of ball B's placement. Here, for example, the placement determination control unit 103 may display a message on the monitor D indicating that the ball is outside the detection range (for example, "Out of zone"), prompting player P to place the ball in an appropriate position.
[0042] On the other hand, as shown in Figure 6A, when player P places ball B in the tee area TE and releases his hand from ball B, as shown in Figure 6B, the placement determination control unit 103 performs predetermined image processing on the captured image 611a of the left shooting area Z11a and the captured image 611b of the right shooting area Z11b, and extracts the outer edge of the object in the captured image 611a of the left shooting area Z11a and the outer edge of the object in the captured image 611b of the right shooting area Z11b. Next, when the placement determination control unit 103 detects the image surrounded by the outer edge of the extracted outer edge of the object as an object image, the right hand image 600, the ball image 601, and the tee image 602 are extracted from the captured image 611a of the left shooting area Z11a and the captured image 611b of the right shooting area Z11b. Furthermore, when the installation determination control unit 103 identifies a circular image that approximates a circle in relation to the detected object image, the ball image 601 is identified as a circular image in both the captured image 611a of the left shooting area Z11a and the captured image 611b of the right shooting area Z11b. The installation determination control unit 103 then acquires the position information of the left trigger area Ta of the left shooting area Z11a where the ball image 601 of the circular image was identified, and determines whether the ball image 601 identified in the left shooting area Z11a is contained within the left trigger area Ta. The setting determination control unit 103 also acquires the position information of the right trigger area Tb of the right shooting area Z11b, and determines whether the ball image 601 identified in the right shooting area Z11b is contained within the right trigger area Tb.
[0043] As a result of the determination, as shown in Figure 6B, if the ball image 601 is not contained within the left trigger area Ta in the left shooting area Z11a, but the ball image 601 is contained within the right trigger area Tb in the right shooting area Z11b, the placement determination control unit 103 determines that ball B is placed in either the left trigger area Ta of the left shooting area Z11a or the right trigger area Tb of the right shooting area Z11b (Figure 4: S105YES). This makes it possible to determine the placement of ball B with high accuracy. In addition, if ball B is detected in the left trigger area Ta of the left shooting area Z11a or the right trigger area Tb of the right shooting area Z11b by the left and right cameras 11a and 11b, it is determined that ball B is placed in either the left trigger area Ta or the right trigger area Tb.
[0044] Here, for example, when determining the installation of the ball B only with an infrared sensor, the hands or club C of the player P may become noise, and although the ball B is not installed, the ball B may be erroneously detected as being installed. Also, although the ball B is not set at a desired position, the infrared sensor may erroneously detect that the ball B is installed. In the present invention, by analyzing the captured images of the left and right cameras 11a and 11b, it is possible to accurately determine the installation of the ball B without causing false detection.
[0045] Further, in the present invention, a trigger region is provided in the captured image, and when the specified ball image is included inside the trigger region, it is determined that the ball B is installed. That is, using the positional relationship between the trigger region and the ball B, the installation of the ball B is determined only when the ball B enters the trigger region. Here, since the trigger region is an area that can be surely detected by the left and right infrared sensors 10a and 10b, the player P can accurately install the ball B in the trigger region that can be detected by the left and right infrared sensors 10a and 10b.
[0046] By the way, as described above, the installation determination control unit 103 determined whether ball B was placed in either the left trigger area Ta of the left shooting area Z11a or the right trigger area Tb of the right shooting area Z11b. However, it is not limited to this, and for example, the installation determination control unit 103 may use one of the left and right cameras 11a and 11b, which is pre-set by player P, to determine whether ball B is placed in the trigger area of the shooting area. For example, if information on player P's dominant hand (right-handed or left-handed) is set in the ball launch analysis device 1, the installation determination control unit 103 will use the camera corresponding to player P's dominant hand to determine whether ball B is placed in the trigger area of the shooting area. Specifically, if player P is right-handed, player P launches ball B from right to left relative to the ball launch analysis device 1, so the installation determination control unit 103 will use the right camera 11b to determine whether ball B is placed in the trigger area Tb of the right shooting area Z11b. On the other hand, if player P is left-handed, player P launches ball B from left to right towards the ball launch analysis device 1. In this case, the placement determination control unit 103 uses the left camera 11a to determine whether ball B is placed in the trigger area Ta of the left shooting area Z11a. This reduces the amount of processing required and makes it possible to determine the placement of ball B with high accuracy.
[0047] Furthermore, when the placement determination control unit 103 determines that ball B is placed in either the left trigger area Ta of the left shooting area Z11a or the left trigger area Tb of the right shooting area Z11b, it may calculate the center coordinates of ball B in the world coordinate system (real coordinate system) using the center coordinates of the camera coordinate system of the ball image 601 used for the determination, the radius of the ball image 601, camera calibration information, and the law of cosines. Here, as shown in Figure 7A, the camera coordinate system has its origin at the center CI of the captured image P corresponding to the focal length f of the camera (for example, the left camera 11a), the left-right direction xi of the captured image P is the x-axis direction, and the up-down direction yi of the captured image is the y-axis direction. The world coordinate system has its origin at the center CR of the camera (left camera 11a), the left-right direction xr of the camera is the x-axis direction, the up-down direction yr of the camera is the y-axis direction, and the front-back direction zr (depth direction) of the camera is the z-axis direction. Camera calibration information is information that associates an arbitrary point in the camera coordinate system with a corresponding point in the world coordinate system, and examples include the K matrix and the P matrix. The captured image P is located perpendicular to the z axis at a distance of focal length f in the z-axis direction from the center CR of the camera (right camera 11a) toward the captured image P. Furthermore, the camera calibration information performs a transformation between the x and y coordinates of the camera coordinate system and the x and y coordinates of the world coordinate system. In addition, the transformation between the z-axis coordinate of the camera coordinate system and the z-axis coordinate of the world coordinate system is performed using the radius b0i of the ball image and the law of cosines. Here, the center coordinates b0c(b0xr, b0yr, b0zr) of ball B in the world coordinate system are calculated using the center coordinates b0c(b0xi, b0yi) of the camera coordinate system of ball image 601, the radius b0i of ball image 601, the camera calibration information of the camera (right camera 11a), and the law of cosines using the angle θ between both ends of ball image 601 and the center CR of the camera (right camera 11a). By combining this with the center coordinates of ball B in the world coordinate system immediately after launch, the flight parameters of ball B can be calculated with high accuracy.
[0048] Further, when the installation determination control unit 103 determines that the ball B is installed in either the left trigger region Ta of the left imaging region Z10a or the left trigger region Tb of the right imaging region Z10b, in the captured image used for the determination, a ball launch prediction region PR along the launch direction of the ball B may be set while including the ball image 601. Here, as shown in FIG. 7A, when the captured image used for the determination is the right captured image 611b (captured image in one direction), a ball launch prediction region PR having a predetermined shape (for example, a rectangular shape) is set along the right direction (one direction) of the ball image 601 corresponding to the launch direction of the ball B (in the world coordinate system, the left direction) while including the ball image 601. Further, the shape of the ball launch prediction region PR is appropriately designed. Thereby, when the ball B immediately after launch is captured, it becomes possible to easily identify the ball image and reduce the processing amount.
[0049] Now, when the determination of the installation determination control unit 103 is completed (FIG. 4: S105 YES), next, the ball launch analysis device 1 transitions to the infrared detection state, and the appearance determination control unit 104 of the ball launch analysis device 1 activates the infrared sensor (here, the right infrared sensor 10b) corresponding to the camera (here, the right camera 11b) of the installation trigger region (here, the right trigger region Tb) where the ball B is installed (FIG. 4: S106). Specifically, as shown in FIG. 7B, the appearance determination control unit 104 enables the right infrared sensor 10b to detect the right detection region Z10b. Note that not only the right infrared sensor 10b alone may be activated (turned on), but both the left infrared sensor 10a and the right infrared sensor 10b may be activated.
[0050] Next, as shown in FIG. 7B, the display control unit 101 displays a message indicating the ready state (for example, "READY") on the monitor D. Thereby, the player P can be notified of the ready state.
[0051] Furthermore, the display control unit 101 uses a camera that captures an image in which the placement of ball B has been determined to occur, and displays the captured image of ball B on monitor D. Here, as shown in Figure 7B, since the placement of ball B has been determined in the right shooting area Z11b of the right camera 11b, the display control unit 101 displays the captured image 71b of the right shooting area Z11b of the right camera 11b on monitor D. This allows player P to confirm the captured image 71b in which ball B has been placed on monitor D.
[0052] Furthermore, the display control unit 101 activates the swing camera 12 (Figure 4: S107) to film the player P's swing. This allows for the recording of a video of the player P's swing from before the swing to after the swing. If the swing camera 12 is not present, the display control unit 101 may omit activating it in S107.
[0053] Furthermore, as shown in Figure 7B, the lighting control unit 102 changes the color of the left and right lights La and Lb to a color indicating the ready state (for example, green) (Figure 4: S108). This allows the player P to be informed of the ready state for the swing. Note that if the left and right lights La and Lb are not present, the lighting control unit 102 may omit the change in S108.
[0054] Next, the appearance determination control unit 104 uses the right infrared sensor 10b to determine whether or not an object has appeared in the installation detection area (right detection area Z10b) which includes the installation trigger area (right trigger area Tb) where the ball B is installed (Figure 4: S109).
[0055] Here, there are no particular limitations on the determination method of the appearance determination control unit 104, but for example, as shown in Figure 8A, the appearance determination control unit 104 acquires the intensity of reflected light from the right detection area Z10b of the right infrared sensor 10b. The appearance determination control unit 104 then determines whether the change in the intensity of reflected light from the right detection area Z10b exceeds a first appearance threshold. The first appearance threshold is set appropriately, for example, based on the intensity of reflected light from club C.
[0056] Here, if the change in the intensity of the reflected light in the right detection area Z10b exceeds the first appearance threshold, the appearance determination control unit 104 determines that an object has appeared in the right detection area Z10b. On the other hand, if the change in the intensity of the reflected light in the right detection area Z10b is within the first appearance threshold, the appearance determination control unit 104 determines that no object has appeared in the right detection area Z10b. In this case, the appearance determination control unit 104 continues to acquire the intensity of the reflected light in the right detection area Z10b and repeats the above determination.
[0057] Now, if player P takes a practice swing away from the batting position S, for example, the intensity of the reflected light in the right detection area Z10b does not change, so the appearance determination control unit 104 determines that no object appears in the installation detection area (Figure 4: S109NO). In this case, the appearance determination control unit 104 returns to S109 and repeats the determination of whether an object has appeared.
[0058] On the other hand, as shown in Figure 8B, when player P attempts to hit ball B using club C, and club C appears in the right detection area Z10b, the appearance determination control unit 104 determines that the change in the intensity of the reflected light in the right detection area Z10b exceeds the first appearance threshold, and determines that an object has appeared in the installation detection area (Figure 4: S109 YES). This makes it possible to accurately detect that player P is attempting to hit ball B with club C without detecting practice swings from other locations.
[0059] Now, once the appearance determination control unit 104 has completed its determination (Figure 4: S109 YES), the disappearance determination control unit 105 of the ball launch analysis device 1 uses the infrared sensor (right infrared sensor 10b) corresponding to the installation detection area (right detection area Z10b) to determine whether or not ball B has disappeared from the installation detection area (right detection area Z10b) where the object appeared (Figure 4: S110).
[0060] Here, there are no particular limitations on the method of determination used by the disappearance determination control unit 105. For example, the disappearance determination control unit 105 acquires the intensity of reflected light from the right detection area Z10b of the right infrared sensor 10b. The disappearance determination control unit 105 then determines whether the change in the intensity of reflected light from the right detection area Z10b exceeds a predetermined disappearance threshold. The disappearance threshold is set appropriately based on the intensity of reflected light from ball B.
[0061] If the change in the intensity of the reflected light in the right detection area Z10b exceeds the disappearance threshold, the disappearance determination control unit 105 determines that ball B has disappeared from the right detection area Z10b. On the other hand, if the change in the intensity of the reflected light in the right detection area Z10b is within the disappearance threshold, the disappearance determination control unit 105 determines that ball B has not disappeared from the right detection area Z10b. In this case, the disappearance determination control unit 105 continues to acquire the intensity of the reflected light in the right detection area Z10b and repeats the above determination.
[0062] Here, as shown in Figure 9A, if player P simply takes a practice swing with club C without hitting ball B, club C passes through the installation detection area Z10b and appears in the adjacent detection area Z10a, but ball B remains in the installation detection area Z10b. In this case, although the intensity of the reflected light in the right detection area Z10b changes temporarily, the presence of ball B ultimately causes the change in the intensity of the reflected light in the right detection area Z10b to fall within the disappearance threshold. Therefore, the disappearance determination control unit 105 determines that ball B does not disappear from the installation detection area Z10b (Figure 4: S110NO). In this case, the disappearance determination control unit 105 returns to S110 and repeats the determination of whether ball B has disappeared.
[0063] On the other hand, as shown in Figure 9B, when player P hits ball B using club C, ball B passes through the installation detection area Z10b together with club C, and ball B moves forward. As a result, the intensity of the reflected light in the right detection area Z10b changes, and the change in the intensity of the reflected light in the right detection area Z10b exceeds the disappearance threshold. Therefore, the disappearance determination control unit 105 determines that ball B has disappeared from the installation detection area Z10b (Figure 4: S110 YES). This makes it possible to accurately detect when ball B is definitely hit without detecting a simple practice swing by player P.
[0064] Now, once the disappearance determination control unit 105 has completed its determination (Figure 4: S110 YES), the next appearance determination control unit 106 of the ball launch analysis device 1 uses an infrared sensor (here, the left infrared sensor 10a) corresponding to the launch detection area (here, the left detection area Z10a) adjacent to the installation detection area Z10b to determine whether or not ball B has appeared in the launch detection area (left detection area Z10a) (Figure 4: S111).
[0065] Here, there are no particular limitations on the determination method of the next appearance determination control unit 106, but for example, the next appearance determination control unit 106 acquires the intensity of reflected light from the left detection area Z10a of the left infrared sensor 10a. Then, the next appearance determination control unit 106 determines whether the change in the intensity of reflected light from the left detection area Z10a exceeds the second appearance threshold. The second appearance threshold is set appropriately based on the intensity of reflected light from ball B.
[0066] Here, if the change in the intensity of the reflected light in the left detection area Z10a exceeds the second appearance threshold, the next appearance determination control unit 106 determines that an object has appeared in the left detection area Z10a. On the other hand, if the change in the intensity of the reflected light in the left detection area Z10a is within the second appearance threshold, the appearance determination control unit 104 determines that no object has appeared in the left detection area Z10a. In this case, the next appearance determination control unit 106 continues to acquire the intensity of the reflected light in the left detection area Z10a and repeats the above determination.
[0067] Here, as shown in Figure 10A, when player P hits ball B with club C, if for some reason ball B does not fly forward in the direction of launch but instead flies to the left or right of the launch direction, or even goes back, and does not fly in the direction of launch, ball B will not appear in the left detection area Z10a. In this case, the next appearance determination control unit 106 determines that the change in the intensity of the reflected light in the left detection area Z10a is within the second appearance threshold (Figure 4: S111NO). In this case, since ball B has disappeared once, the next appearance determination control unit 106 returns to S105, and the placement determination control unit 103 determines the placement of ball B again. In this return step S105, the infrared sensors (for example, only the right infrared sensor 10b, or both the left infrared sensor 10a and the right infrared sensor 10b) are stopped (turned off).
[0068] On the other hand, as shown in Figure 10B, when player P hits ball B forward using club C, ball B appears in the left detection area Z10a. The next appearance determination control unit 106 then determines that the change in the intensity of the reflected light in the left detection area Z10a exceeds the second appearance threshold, and determines that ball B has appeared in the left detection area Z10a (Figure 4: S111YES). This makes it possible to detect that ball B has been hit in the direction of the shot without detecting any unusual shots of ball B.
[0069] Now, once the next appearance determination control unit 106 has completed its determination (Figure 4: S111 YES), the signal transmission control unit 107 of the ball launch analysis device 1 then transmits a trigger signal (Figure 4: S112). The launch time of ball B can be estimated from the time this trigger signal is transmitted.
[0070] Next, once the signal transmission control unit 107 has completed its transmission (Figure 4: S112), the shooting control unit 108 of the ball launch analysis device 1 then uses the left and right cameras 11a and 11b to continuously photograph the ball B in the left shooting area Z11a and the right shooting area Z11b (Figure 4: S113).
[0071] There are no particular limitations on the continuous shooting method of the shooting control unit 108, but for example, when the shooting control unit 108 receives a trigger signal, it uses the left and right cameras 11a and 11b to perform continuous shooting at a predetermined shooting speed (for example, 1000 fps), as shown in Figure 11A. There are no particular limitations on the continuous shooting method, but for example, if the left and right cameras 11a and 11b are low-speed shooting cameras, high-speed shooting can be made possible even with low-speed shooting cameras by applying high-speed shooting software to the left and right cameras 11a and 11b. Also, if the left and right cameras 11a and 11b are high-speed shooting cameras, the shooting control unit 108 can simply perform high-speed shooting with the left and right cameras 11a and 11b.
[0072] Here, as shown in Figure 11B, the shooting control unit 108, at a first time t1 immediately following the activation time t0 of the trigger signal, uses the right camera 11b corresponding to the infrared sensor (right infrared sensor 10b) in the installation detection area Z10b to photograph the ball B in the right shooting area Z11b and acquires the right image 1111b. At a second time t2, obtained by adding a predetermined time (Δt) to the first time t1, the left camera 11a corresponding to the infrared sensor 10a in the launch detection area Z10a is used to photograph the ball B in the left shooting area Z11a and acquires the left image 1111a. The predetermined time (Δt) is set appropriately depending on the performance of the camera. This allows for continuous shooting even of a high-speed ball B by capturing images with the right camera 11b and the left camera 11a in sequence along the launch direction of the ball B.
[0073] Once the shooting control unit 108 completes continuous shooting (Figure 4: S113), the calculation control unit 109 of the ball launch analysis device 1 then calculates the flight parameters of ball B based on the ball images of ball B continuously captured by the left and right cameras 11a and 11b (Figure 4: S114).
[0074] Here, there are no particular limitations on the calculation method of the calculation control unit 109, but for example, the calculation control unit 109 identifies the ball image from images taken at two different times by performing the image processing S105 described above on two consecutively captured images. For example, as shown in Figure 11B, the calculation control unit 109 performs image processing on the first captured image at the first time t1 (here, the right captured image 1111b) and the second captured image at the second time t2 (here, the left captured image 1111a). Then, the calculation control unit 109 identifies the first ball image b1 from the first captured image 1111b at the first time t1 and identifies the second ball image b2 from the second captured image 1111a at the second time t2.
[0075] Next, the calculation control unit 109 performs the image processing described in S105YES above to calculate the center coordinates of the ball image in the world coordinate system using the center coordinates of the identified ball image in the camera coordinate system, the radius of the ball image, camera calibration information, and the law of cosines. Here, as shown in Figure 12A, the calculation control unit 109 uses the center coordinates b1c(b1xi, b1yi) of the camera coordinate system of the first ball image b1, the radius b1i of the first ball image b1, the camera calibration information of the right camera 10b, and the law of cosines to calculate the center coordinates b1c(b1xr, b1yr, b1zr) of the world coordinate system of the first ball B (ball B at the first time t1) corresponding to the first ball image b1. Next, the calculation control unit 109 uses the center coordinates b2c(b2xr, b2yr, b2zr) of the world coordinate system of the second ball B (ball B at the second time t2) corresponding to the second ball image b2, using the center coordinates b2c(b2xi, b2yi) of the camera coordinate system of the second ball image b2, the radius b2i of the second ball image b2, the camera calibration information of the left camera 10a, and the law of cosines.
[0076] The calculation control unit 109 then uses the center coordinates of the world coordinate system of ball B at two different times to calculate the ball speed BS (m / s), launch angle LA (degrees), and side angle SA (degrees) from among the flight parameters. Here, ball speed BS is the value obtained by dividing the ball distance between the center coordinates b2c (b2xr, b2yr, b2zr) of the second ball B's world coordinate system and the center coordinates b1c (b1xr, b1yr, b1zr) of the first ball B's world coordinate system by the subtraction time obtained by subtracting the first time t1 from the second time t2. Launch angle LA means the angle formed by the ball distance and the horizontal plane. Side angle SA is the angle of the left and right curving directions relative to the launch direction of ball B, for example, the angle of the left and right curving directions in the z-axis direction relative to the x-axis direction of the launch direction. Furthermore, the calculation control unit 109 calculates the carry CA (m) using the ball speed BS and the formula for the parabola of ball B. Carry CA is the distance from the point where ball B was struck to the point where it landed, and can be obtained by substituting the ball speed BS as the initial velocity into the formula for the parabola of ball B. Carry CA can also be converted from m to yards (YDS), where 1 yard is 0.9144 m. In this way, the ball speed BS, launch angle LA, side angle SA, and carry CA can be calculated from the center coordinates of the world coordinate system of ball images at two different times.
[0077] Furthermore, the calculation control unit 109 calculates the rotation axis SX0 and rotation rate TS0 of ball B using ball images b1 and b2 from two different time points. For example, as shown in Figure 12B, the calculation control unit 109 matches the size of the first ball image b1 at the first time point t1 to the size of the second ball image b2 at the second time point t2, virtually rotates the first ball image b1 whose size has been matched, and matches the surface image of the virtually rotated first ball image b1 to the surface image of the second ball image b2. The calculation control unit 109 calculates the rotation axis SX0 and rotation rate TS0 of the virtually rotated first ball image b1 whose surface images match. Then, the calculation control unit 109 calculates the backspin BS (rpm) and sidespin SS (rpm) using the calculated rotation axis SX0 and rotation rate TS0. Backspin (BS) refers to the rotational speed of ball B in the opposite direction to its launch direction, while sidespin (SS) refers to the rotational speed of ball B in the direction of curving to the left or right relative to its launch direction. For example, it refers to the rotational speed in the z-axis direction of the curving direction relative to the x-axis direction of the launch direction. In this way, backspin (BS) and sidespin (SS) can be calculated from ball images taken at two different times.
[0078] As mentioned above, flight parameters can include, for example, ball speed BS, launch angle LA, side angle SA, carry CA, backspin BS, and sidespin SS, but other flight parameters may also be added.
[0079] By the way, as described above, the shooting control unit 108 took a picture of ball B using the right camera 11b at the first time t1 and took another picture using the left camera 11a at the second time t2. However, it is not limited to this. For example, if the camera is a high-performance camera, as shown in Figure 13A, the shooting control unit 108 may take a picture of ball B in the right shooting area Z11b using the right camera 11b at the first time t1 and acquire the right image 1311b, and then take another picture of ball B in the right shooting area Z11b using the same right camera 11b at the second time t2 and acquire the right image 1311b. In this case, the calculation control unit 109 can calculate the flight parameters of ball B using the two right images 1311b taken at the first time t1 and the second time t2.
[0080] Furthermore, as described above, the calculation control unit 109 identified the ball image by performing the image processing S105 on all captured images. However, it is not limited to this. For example, if the placement determination control unit 103 sets a ball launch prediction region PR for the captured image, as shown in Figure 13B, the calculation control unit 109 may set the ball launch prediction region PR on the captured image 1411b at the first time t1, perform the predetermined image processing described above on the ball launch prediction region PR to identify the first ball image b1, and calculate the flight parameters of ball B. This makes it easier to identify the ball image and reduces the amount of processing required.
[0081] Furthermore, as described above, as shown in Figure 12, the calculation control unit 109 calculated the flight parameters of ball B using the right image 1111b taken at the first time t1 and the right image 1111a taken at the second time t2. However, it is not limited to this, and for example, the installation determination control unit 103 may calculate the flight parameters of ball B by adding the center coordinates b0c (b0xr, b0yr, b0zr) of ball B in the world coordinate system at the time of installation (in other words, the time t0 when the trigger signal is transmitted, or the time t0 when ball B appears in the installation trigger zone) to the center coordinates b1c (b1xr, b1yr, b1zr) of the first ball B in the world coordinate system at the first time t1 and the center coordinates b2c (b2xr, b2yr, b2zr) of the second ball B in the world coordinate system. This makes it possible to calculate the flight parameters of ball B with high accuracy. Time t0 corresponds, for example, to the center coordinate b0c of the installed ball B in the world coordinate system. Time t1 is the time when the first image of ball B, which has moved after the device received the trigger signal, is taken, and corresponds to the center coordinate b1c of the first ball B in the world coordinate system. Time t2 is the time when the second image of ball B, which has moved a certain amount of time after time t1 (for example, equivalent to 1 ms, 1000 fps), is taken, and corresponds to the center coordinate b2c of the second ball B in the world coordinate system.
[0082] Now, once the calculation control unit 109 has finished calculating the flight parameters (Figure 4: S114), the calculation control unit 109 then determines whether the calculated flight parameters are normal or not (Figure 4: S115).
[0083] Here, there are no particular limitations on the determination method of the calculation control unit 109, but for example, the calculation control unit 109 refers to the normal flight parameter range pre-set in a predetermined memory and determines whether the calculated flight parameter falls within the normal flight parameter range. Specifically, if the flight parameter is ball speed BS, the normal flight parameter range is set to, for example, 1 m / s or more, and the calculation control unit 109 determines whether the ball speed BS of the calculated flight parameter is 1 m / s or more within the normal flight parameter range. If the ball speed BS is 1 m / s or more within the normal flight parameter range, it can be determined that ball B flew normally. Also, if the flight parameter is launch angle LA, the normal flight parameter range is set to, for example, 70 degrees or less, and the calculation control unit 109 determines whether the launch angle LA of the calculated flight parameter is 70 degrees or less within the normal flight parameter range. If the launch angle LA is 70 degrees or less within the normal flight parameter range, it can be determined that ball B flew normally. Such processing can be designed appropriately depending on the type of flight parameter, and can be performed on all flight parameters or only on specific flight parameters. By determining whether the flight parameters are normal or not in this way, it is possible to detect if a calculation error has occurred for any reason.
[0084] If the calculation results in abnormal flight parameters, the calculation control unit 109 determines that player P's shot has failed (Figure 4: S115NO). In this case, the calculated flight parameters are not displayed, and the system proceeds to S105, prompting player P to place ball B again.
[0085] On the other hand, if the calculated flight parameters are normal as a result of the judgment, the calculation control unit 109 determines that player P's shot was successful (Figure 4: S115 YES). This makes it possible to display only the appropriate flight parameters. Note that the judgment process in S115 may be omitted.
[0086] Once the calculation control unit 109 has completed the calculation, the display control unit 101 displays the calculated flight parameters on the monitor D (Figure 4: S116).
[0087] Here, there are no particular limitations on the display method of the display control unit 101, but for example, as shown in Figure 14, the display control unit 101 displays the calculated carry CA (YDS), ball speed BS (m / s), launch angle LA (DEG), side angle SA (DEG), backspin BS (RPM), and sidespin SS (RPM) values on the screen 1400 of the monitor D. This allows the player P to know the flight parameters of the ball B for their own swing.
[0088] Furthermore, if the swing camera 12 is activated (Figure 4: S107), the display control unit 101 displays the flight parameters (Figure 4: S116) and then displays the video (or images) captured by the swing camera 12 (Figure 4: S117). Here, as described above, using the transmission time of the trigger signal indicating the launch of ball B, the display control unit 101 acquires the video before and after the transmission time of the trigger signal as a swing video, and displays the swing video 1401 from before the player P swings until after the swing, as shown in Figure 14. This allows the player P to check their own swing in video (or images). Note that if the swing camera 12 is not present, the display control unit 101 may omit the activation in S117.
[0089] Then, after the display control unit 101 displays the flight parameters (Figure 4: S116), or after the video captured by the swing camera 12 is displayed (Figure 4: S117), the ball launch analysis device 1 terminates processing. If player P swings again, they can operate the ball launch analysis device 1 to return to S101 or S102 and repeat the above processing. If processing returns to allow player P to make a new swing, the ball launch analysis device 1 can return to S103, S104, or S105 as needed. Specifically, the ball launch analysis device 1 causes the LED to light up red and the screen to switch to a ball search display.
[0090] Thus, by appropriately combining an infrared sensor and a camera, the present invention makes it possible to perform highly accurate analysis of the ball's flight parameters, from launch to the launch of the ball.
[0091] The effects of the present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.
[0092] First, a prototype ball launch analysis device 1 was fabricated based on Figures 1-14, and this ball launch analysis device 1 was used as the embodiment. Using the ball launch analysis device 1 of the embodiment, when images were captured when player P launched ball B, two images were obtained, as shown in Figure 15: a first image 1511b at time t1 and a second image 1511a at time t2. Using these two images, normal flight parameters could be calculated.
[0093] Furthermore, as shown in Figure 15, by setting the ball launch prediction area PR in the captured image 1511b0 at the time of installation t0, the amount of processing required to identify the first ball image b1 in the captured image 1511b at the first time t1 is reduced, and the identification of the first ball image b1 becomes easier.
[0094] Next, the flight parameters were calculated using the image taken at installation time t0, the image taken at the first time t1, and the image taken at the second time t2. When the ball launch analysis device 1 of the embodiment determined that ball B was placed in the trigger area, as shown in Figure 16, the left camera 11a acquired the first image 1611a0 taken at installation time t0, and the right camera 11b acquired the second image 1611b0 taken at installation time t0, and the center coordinates of ball B in the world coordinate system were calculated. Next, when ball B was launched by player P, the ball launch analysis device 1 of the embodiment detected the launch of ball B using the left and right infrared sensors 10a and 10b, acquired the third image 1611b1 taken at the first time t1 with the right camera 11b, and acquired the fourth image 1611a2 taken at the second time t2 with the left camera 11a. Then, using the first captured image 1611a0, the second captured image 1611b0, the third captured image 1611b1, and the fourth captured image 1611a2, the ball launch analysis device 1 of the embodiment calculated the flight parameters, and the ball speed BS was 28.4 (m / s), the launch angle LA was 22.4 (degrees), the side angle SA was 3.6 (degrees), the backspin BS was 3335.1 (rpm), and the sidespin SS was 487.3 (rpm). Furthermore, from the backspin BS and sidespin SS, the rotation axis SX0 (SPIN AXIS) was 8.3 (rpm), and the rotation rate TS0 (TOTAL SPIN) was 3370.5 (rpm). These values are equivalent to those of commercially available flight parameter analysis devices and were normal flight parameters.
[0095] In the embodiments of the present invention, a ball launch analysis device 1 applied to a golf ball was described, but the present invention is not limited to this, and can be broadly applied as a device that performs everything from launching a stationary ball B in ball games such as baseball, tennis, soccer, rugby, ice hockey, and gateball, to analyzing the flight parameters of the ball.
[0096] Furthermore, in the embodiment of the present invention, a rectangular detection area was formed in the infrared sensor using a slit, but the invention is not limited to this, and detection areas of various shapes may be formed. Moreover, in the embodiment of the present invention, first, an infrared sensor corresponding to the camera in the installation trigger area is used to determine whether or not an object has appeared in the installation detection area, and when that object disappears, an infrared sensor corresponding to the launch detection area adjacent to the installation detection area is used to determine whether or not a ball has appeared, but the invention is not limited to this. For example, when a ball is placed in either the left trigger area or the right trigger area, an infrared sensor corresponding to the camera in the installation trigger area is used to determine whether or not a ball has appeared, and the infrared sensor corresponding to the launch detection area adjacent to the installation detection area is also activated, and it is possible to determine later whether or not a ball has appeared. In other words, in that case, the left and right infrared sensors 10a and 10b may be activated.
[0097] Furthermore, in the embodiment of the present invention, the ball launch analysis device 1 is configured to include each control unit, but it is also possible to configure the device to store a program that implements each of these control units on a storage medium and provide the storage medium. In this configuration, the program is read by the device, and the device implements each of the control units. In that case, the program read from the recording medium itself performs the effects of the present invention. Moreover, it is also possible to provide a method for storing the processes executed by each control unit on a hard disk.
[0098] As described above, the ball launch analysis device and ball launch analysis method according to the present invention are effective devices and methods applicable to all ball games in which a stationary ball is launched. By appropriately combining an infrared sensor and a camera, the ball launch analysis device and ball launch analysis method are effective in that they can perform highly accurate analysis from the launch of the ball to the analysis of the ball's flight parameters.
[0099] 1 Ball launch analysis device 101 Display control unit 102 Lighting control unit 103 Installation determination control unit 104 Appearance determination control unit 105 Disappearance determination control unit 106 Next appearance determination control unit 107 Signal transmission control unit 108 Shooting control unit 109 Calculation control unit
Claims
1. Left and right infrared sensors provided on each side of the device, capable of detecting the left detection area and the right detection area respectively, wherein the left detection area and the right detection area are adjacent to each other and do not overlap; Left and right cameras provided on each side of the device, capable of photographing the left shooting area and the right shooting area, respectively, which include the left detection area and the right detection area, wherein the left shooting area and the right shooting area overlap each other; Installation determination control unit that uses the left and right cameras to determine whether a ball is placed in either the left trigger area, which is pre-set within the left detection area of the left shooting area, or the right trigger area, which is pre-set within the left detection area of the right shooting area; Appearance determination control unit that, if the installation determination control unit determines that the ball is placed in either the left trigger area or the right trigger area, uses the infrared sensor corresponding to the camera in the installation trigger area where the ball is placed to determine whether an object has appeared in the installation detection area, which includes the installation trigger area. A ball launch analysis apparatus comprising: an appearance determination control unit that determines whether the ball has disappeared from the installation detection area using an infrared sensor corresponding to the installation detection area when the appearance determination control unit determines that an object has appeared in the installation detection area; a next appearance determination control unit that determines whether the ball has appeared in the launch detection area using an infrared sensor corresponding to a launch detection area adjacent to the installation detection area when the disappearance determination control unit determines that the ball has disappeared from the installation detection area; a signal transmission control unit that transmits a trigger signal when the next appearance determination control unit determines that the ball has appeared in the launch detection area; an imaging control unit that, when the trigger signal is transmitted, uses the left and right cameras to continuously photograph the ball in the left and right imaging areas; and a calculation control unit that calculates the flight parameters of the ball based on the ball images of the ball continuously photographed by the left and right cameras.
2. The ball launch analysis apparatus according to claim 1, wherein the shooting control unit captures a ball image of the shooting area using a camera corresponding to the infrared sensor of the installation detection area at a first time immediately following the transmission time of the trigger signal, and captures a ball image of the shooting area using a camera corresponding to the infrared sensor of the launch detection area at a second time obtained by adding a predetermined time to the first time.
3. The ball launch analysis apparatus according to claim 1, wherein when the installation determination control unit determines that a ball has been placed in either the left trigger area of the left shooting area or the right trigger area of the right shooting area, it sets a ball launch prediction area in the captured image used for the determination, which includes the ball image and is aligned with the launch direction of the ball; and the calculation control unit sets the ball launch prediction area in the captured image at a first time immediately following the transmission time of the trigger signal, performs predetermined image processing on the ball launch prediction area to identify the ball image, and calculates the flight parameters of the ball.
4. A ball launch analysis method for a ball launch analysis apparatus comprising:
4. Left and right infrared sensors provided on the left and right sides of the apparatus, capable of detecting a left detection area and a right detection area, respectively, wherein the left detection area and the right detection area are adjacent to each other and do not overlap; 5. Left and right cameras provided on the left and right sides of the apparatus, capable of photographing a left shooting area and a right shooting area, respectively, which include the left detection area and the right detection area, respectively, wherein the left shooting area and the right shooting area overlap each other; 6. A placement determination control step using the left and right cameras to determine whether a ball has been placed in either a left trigger area, which is pre-set within the left detection area of the left shooting area, or a right trigger area, which is pre-set within the right detection area of the right shooting area; 7. If the placement determination control step determines that the ball has been placed in either the left trigger area or the right trigger area, a presence determination control step using an infrared sensor corresponding to the camera in the placement trigger area where the ball was placed to determine whether an object has appeared in the placement detection area, which includes the placement trigger area; A ball launch analysis method comprising: an appearance determination control step which determines whether the ball has disappeared from the installation detection area using an infrared sensor corresponding to the installation detection area if the appearance determination control step determines that an object has appeared in the installation detection area; a next appearance determination control step which determines whether the ball has appeared in the launch detection area using an infrared sensor corresponding to a launch detection area adjacent to the installation detection area if the disappearance determination control step determines that the ball has disappeared from the installation detection area; a signal transmission control step which transmits a trigger signal if the next appearance determination control step determines that the ball has appeared in the launch detection area; a shooting control step which, when the trigger signal is transmitted, uses the left and right cameras to continuously photograph the ball in the left shooting area and the right shooting area; and a calculation control step which calculates the flight parameters of the ball based on the ball images of the ball continuously photographed by the left and right cameras.