Home plate having strike zone determination function

Abstract

The present invention relates to a home plate having a strike zone determination function, wherein a stereo camera is embedded in a main body of the home plate and can determine whether a baseball thrown by a pitcher is a strike or ball by determining whether the baseball passes through a strike zone of the home plate, and display the state thereof. The home plate having a strike zone determination function according to the present invention determines whether a baseball thrown by a pitcher is a strike or ball by determining whether the baseball passes through a strike zone of the home plate, and displays the determination result, and thus can be used to determine strikes and balls in an actual baseball game, and has the advantage of allowing a pitcher or batter to accurately determine strikes and balls even when practicing alone.

Description

Home plate with strike zone judgment function

[0001] The present invention relates to a home plate used in a baseball game, and more particularly, to a home plate equipped with a strike zone judgment function implemented so as to determine whether a ball thrown by a pitcher passes through the strike zone of the home plate by embedding a stereo camera inside the home plate body, thereby determining whether it is a strike or a ball and displaying the status.

[0002] Professional baseball, which has been enjoying explosive popularity with the number of spectators visiting baseball stadiums increasing exponentially in recent years, can be said to be one of the most popular sports in Korea.

[0003] However, during a game, the game is often interrupted due to arguments between the batter, umpire, manager, and umpire regarding strikes or balls, or the ejection of players or managers, which reduces the enjoyment of the game. In the long term, this hinders the popularity and development of professional baseball.

[0004] In baseball, the strike zone is typically determined by the umpire's visual judgment, which is then applied to the ball count. However, the umpire's visual judgment can be inaccurate, leading to frequent disputes over whether a ball or strike is called.

[0005] These types of judging disputes are especially common when the umpire is not present on the field and is judging good and bad balls, or when amateurs are temporarily acting as umpires, as in baseball practice fields.

[0006] If we eliminate the risk of errors in visual judgment and use a more accurate mechanical device to determine strike-ball (strike zone), the strike zone will be determined automatically using accurate data, so the number of disputes over strike zone decisions will gradually decrease, and we will be able to enjoy a more enjoyable baseball game by preventing game stoppages or players or managers being ejected in advance.

[0007] The present invention is intended to solve the above-mentioned problem, and the technical problem to be solved by the present invention is to provide a home plate having a strike zone judgment function that can determine whether a baseball thrown by a pitcher passes through the strike zone of the home plate using a stereo camera built into the home plate main body, and can display the judgment as to whether it is a strike or a ball, and can prevent problems due to backlighting by arranging cameras at various angles.

[0008] A home plate having a strike zone determination function according to one embodiment of the present invention for achieving the above technical task is characterized by including: a home plate main body; a stereo camera unit built into the interior of the home plate main body; a control unit for determining whether a baseball passes through the strike zone using an image captured and transmitted from the stereo camera unit when the baseball passes near the home plate main body; and a light-emitting unit provided in the home plate main body.

[0009] A home plate having a strike zone judgment function according to one embodiment of the present invention may further include a power supply unit that supplies power to the stereo camera unit, the control unit, and the light emitting unit.

[0010] The above power supply unit can be connected to an AC power source while embedded in the home plate body or implemented in the form of a battery.

[0011] The above light emitting part is characterized in that it emits a first color when it is determined that the baseball has passed through the strike zone, emits a second color when it is determined that the baseball has not passed through the strike zone, and emits a third color when an abnormality occurs in the home plate main body.

[0012] It is preferable that the above stereo camera unit includes at least two stereo cameras.

[0013] The above control unit is capable of measuring the speed of the baseball, the rotational speed of the baseball, and the trajectory of the baseball in three dimensions using images captured by at least two stereo cameras.

[0014] In addition, the control unit can measure in three dimensions the speed of the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat using images captured using the at least two stereo cameras when the batter swings the bat.

[0015] The control unit can transmit information about the speed of the baseball, the rotational speed of the baseball, the trajectory of the baseball, the speed of the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat to the user's smart device through an app.

[0016] According to the home plate having a strike zone judgment function according to the present invention, the strike zone can be set differently depending on the batter's height.

[0017] It is preferable that the surface of the home plate body be formed of a material that can protect the light-emitting part, the stereo camera part, and the control part and prevent injuries to players.

[0018] It is preferable that the above stereo camera unit be configured to have multiple stereo cameras positioned at various angles so that the trajectory of the baseball can be recognized even when backlighting occurs.

[0019] The above control unit uses an image captured using a stereo camera other than the stereo camera to which backlight is incident when backlight is incident on some of the at least two stereo cameras.

[0020] According to a home plate equipped with a strike zone judgment function according to the present invention, a stereo camera built into the home plate body is used to judge whether a baseball thrown by a pitcher passes through the strike zone of the home plate, thereby judging whether it is a strike or a ball and displaying the result, thereby having the effect of being used for strike ball judgment in an actual baseball game.

[0021] Additionally, when a pitcher practices alone, he can accurately determine whether the ball he throws passes through the strike zone, and when a batter practices alone, he can accurately determine whether the ball from the pitching machine is a strike or a ball.

[0022] Meanwhile, the speed, trajectory, and spin rate of a baseball can be measured using a stereo camera built into the home plate body, and there is an advantage in that the bat speed, bat trajectory, speed of the batted ball, and launch angle can be measured when the batter swings.

[0023] Additionally, the strike zone can be adjusted to suit the batter's height, and there is the advantage of being able to adjust the degree of strictness of the strike zone.

[0024] In addition, according to the home plate equipped with a strike zone judgment function according to the present invention, by arranging stereo cameras in various forms, there is an effect in which the trajectory of a baseball can be recognized using other stereo cameras even when backlight occurs on some cameras.

[0025] FIG. 1 is a drawing showing the configuration of a home plate equipped with a strike zone judgment function according to the present invention.

[0026] FIG. 2 is a drawing showing the operating state of a home plate equipped with a strike zone judgment function according to the present invention.

[0027] FIG. 3 is a drawing for explaining setting a strike zone at a home plate equipped with a strike zone judgment function according to the present invention.

[0028] FIG. 4 is a drawing for explaining an additional function of a home plate equipped with a strike zone judgment function according to the present invention.

[0029] FIG. 5 is a drawing for explaining calculating the speed, direction, and launch angle of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0030] FIG. 6 is a flowchart illustrating a process for measuring the number of spins of a baseball using a home plate equipped with a strike zone determination function according to the present invention.

[0031] FIG. 7 is a drawing for explaining a correction matrix calculation step for camera correction in a process of measuring the number of spins of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0032] FIG. 8 is a drawing for explaining a process of generating a rotation image in a process of measuring the rotation number of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0033] FIG. 9 is a drawing for explaining a process of determining a spin axis and spin amount in a process of measuring the number of spins of a baseball using a home plate equipped with a strike zone determination function according to the present invention.

[0034] FIG. 10 is a drawing showing various camera arrangement states of a home plate equipped with a strike zone judgment function according to the present invention.

[0035] FIG. 11 is a drawing for explaining the operating principle of a home plate equipped with a strike zone judgment function according to the present invention in a backlit state.

[0036] Hereinafter, a home plate equipped with a strike zone judgment function according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0037] The terms and words used in this specification and claims are not to be construed as limited to their conventional or dictionary meanings. Rather, they should be construed in a way that reflects the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of a term to best describe his or her invention. Therefore, the embodiments described in this specification and the configurations depicted in the drawings are merely the most preferred embodiments of the present invention, and it should be understood that various equivalents and modifications may be substituted for them at the time of filing this application.

[0038] FIG. 1 is a drawing showing the configuration of a home plate having a strike zone judgment function according to the present invention, and FIG. 2 is a drawing showing the operating state of a home plate having a strike zone judgment function according to the present invention.

[0039] Referring to FIGS. 1 and 2, a home plate (100) equipped with a strike zone judgment function according to the present invention comprises a home plate main body (110), a stereo camera unit (120), a control unit (130), and a light emitting unit (140).

[0040] The home plate body (110) is formed in a pentagonal plate shape like the home plate used in regular baseball games.

[0041] The stereo camera unit (120) is formed by being built into the interior of the home plate main body (110). At this time, the stereo camera unit (120) may include at least two stereo cameras (120a, 120b).

[0042] The control unit (130) determines whether the baseball passes through the strike zone by using images captured and transmitted from at least two stereo cameras (120a, 120b) included in the stereo camera unit (120) when the baseball passes near the home plate main body (110).

[0043] A light-emitting part (140) is provided in the home plate main body (110). The light-emitting part (140) may be formed with a plurality of light-emitting diodes (LEDs) formed in one part or an edge part of the inside of the home plate main body (110).

[0044] The above light emitting part (140) can emit a first color when it is determined that the baseball has passed through the strike zone, emit a second color when it is determined that the baseball has not passed through the strike zone, and emit a third color when an abnormality occurs in the home plate body.

[0045] Figure 2 (a) shows the state of the system's readiness, (b) shows the state in which the baseball passes through the strike zone and is a strike, (c) shows the state in which the baseball does not pass through the strike zone and is a ball, and (d) shows the state in which an abnormality occurs in the home plate body and cleaning of foreign substances is required.

[0046] Therefore, it is possible to quickly determine whether it is a strike or a ball based on the color emitted from the light emitting unit (140), and additionally, it is possible to quickly determine whether there is an abnormality in the home plate.

[0047] Meanwhile, the home plate (100) equipped with a strike zone judgment function according to the present invention may further include a power supply unit (not shown) that supplies power to the stereo camera unit, the control unit, and the light emitting unit. The power supply unit may be connected to an AC power source while embedded in the home plate main body unit (110) or may be implemented in the form of a battery. When the power supply unit is connected to an AC power source while embedded in the main body unit (110), the home plate (100) is operated in a fixed manner, and when the power supply unit is implemented in the form of a battery, the home plate (100) may be operated in a movable manner.

[0048] FIG. 3 is a drawing for explaining setting a strike zone in a home plate having a strike zone judgment function according to the present invention, and FIG. 4 is a drawing for explaining an additional function of a home plate having a strike zone judgment function according to the present invention.

[0049] Referring to FIG. 3, the home plate (100) equipped with a strike zone judgment function according to the present invention first uses a separate jig to initialize the position of the stereo camera included in the stereo camera unit (120) and recognizes the position of each point.

[0050] Afterwards, the preset value is added in the vertical (Z-axis) direction from the first point (A1) to move to the second point (A2) to determine the lowest point in the vertical (Z-axis) direction of the strike zone. Next, a value input differently depending on the batter's height is added to determine the highest point in the vertical (Z-axis) direction of the strike zone, which is the third point (A3).

[0051] If the trajectory of the baseball passes within the XYZ coordinates of the strike zone set in the above manner, it is judged to be a strike.

[0052] Referring to FIG. 4, the control unit (130) of the home plate (100) equipped with a strike zone judgment function according to the present invention can measure the speed of the baseball, the rotational speed of the baseball, and the trajectory of the baseball in three dimensions using images captured by at least two stereo cameras included in the stereo camera unit (120).

[0053] In addition, the control unit (130) can measure in three dimensions the speed of the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat, etc., by using images captured by at least two stereo cameras included in the stereo camera unit (120) when the batter swings the bat.

[0054] Meanwhile, in the present invention, information on the speed of the baseball, the rotational speed of the baseball, the trajectory of the baseball, the speed of the bat when the batter swings the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat, measured by the control unit (130), may be transmitted to the user through a separate app by connecting to the user's smart device.

[0055] FIG. 5 is a drawing for explaining calculating the speed, direction, and launch angle of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0056] Referring to Figure 5, the 3D recognition coordinates of the baseball are B1(x1, y1, z1), B2(x2, y2, z2), and the progress vector of the baseball is and if the elapsed time is t, the progress vector of the baseball is is as follows.

[0057]

[0058] At this time, the velocity (v) of the baseball, the direction (θ) of the baseball with respect to the +x axis, and the launch angle (Φ) of the baseball can be calculated as follows.

[0059]

[0060]

[0061]

[0062]

[0063] FIG. 6 is a flowchart illustrating a process for measuring the rotational speed of a baseball using a home plate equipped with a strike zone determination function according to the present invention.

[0064] Referring to FIG. 6, the process (600) of measuring the number of spins of a baseball using a home plate equipped with a strike zone determination function according to the present invention includes a correction matrix calculation step (S610) for camera correction, a three-dimensional coordinate conversion step (S620) for converting the position coordinates of a feature part into three-dimensional coordinates, a rotation step (S630) for rotating the extracted three-dimensional coordinates with an arbitrary spin, a two-dimensional coordinate conversion step (S640) for converting the rotated coordinates into two-dimensional coordinates, a comparison step (S650) for comparing an image converted into two-dimensional coordinates using a matching algorithm with a target image, and a decision step (S660) for determining the final spin axis and spin amount.

[0065] FIG. 7 is a drawing for explaining a correction matrix calculation step for camera correction in a process of measuring the number of spins of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0066] When capturing an image of a baseball using a stereo camera, as illustrated in FIG. 7, the first camera (Cam_B) and the second camera (Cam_T) view different positions, and the baseball moves at each moment, so the actual captured image has different view points. Therefore, in order to extract information about the rotation of the baseball, it is necessary to align the view points to the same extent, and for this purpose, a camera calibration process is required.

[0067] Additionally, distortion occurs within each single camera image separately, so it is necessary to correct this.

[0068] FIG. 8 is a drawing for explaining a process of generating a rotation image in a process of measuring the rotational speed of a baseball using a home plate equipped with a strike zone judgment function according to the present invention.

[0069] Figure 8 illustrates generating a rotated image through transformation between three-dimensional coordinates and two-dimensional coordinates.

[0070] A reference image having two-dimensional coordinates as shown in (a) is converted into three-dimensional coordinates as shown in (b), the extracted three-dimensional coordinates are rotated by an arbitrary spin, and then the rotated coordinates are converted into two-dimensional coordinates as shown in (c) to generate a rotated image. Thereafter, the rotated image is compared with a target image.

[0071] FIG. 9 is a drawing for explaining a process of determining a spin axis and spin amount in a process of measuring the number of spins of a baseball using a home plate equipped with a strike zone determination function according to the present invention.

[0072] First, in Frame 1 and Frame 2, we extract areas that are distinctive features that stand out from the surrounding background, such as the baseball's threads or logo.

[0073] Next, a rotation image is generated by rotating the first frame (Frame 1) to the second frame (Frame 2) while changing the spin axis and spin rate for an area (920) having a horizontal and vertical offset from the center point (910) of the baseball.

[0074] Afterwards, the generated rotation image is compared with the image in the second frame (Frame 2), and the point where the feature elements of the baseball are most identical is found, and the spin axis and spin rate are determined based on that point.

[0075] FIG. 10 is a drawing showing various camera arrangement states of a home plate equipped with a strike zone judgment function according to the present invention, and FIG. 11 is a drawing for explaining the operating principle of a home plate equipped with a strike zone judgment function according to the present invention in a backlight state.

[0076] As illustrated in FIG. 10, a home plate equipped with a strike zone judgment function according to the present invention has a plurality of stereo cameras positioned at various angles to cope with a situation where it is impossible to recognize the trajectory of a baseball due to backlighting.

[0077] Figure 10 (a) shows a case where two stereo cameras are arranged vertically, (b) shows a case where two stereo cameras are arranged horizontally, (c) shows a case where three stereo cameras are arranged in a triangle, (d) shows a case where four stereo cameras are arranged in a square, and (e) shows a case where five stereo cameras are arranged in an inverted pentagon.

[0078] The home plate equipped with a strike zone judgment function according to the present invention can recognize the trajectory of a baseball using other stereo cameras even when backlight occurs on some cameras by arranging stereo cameras in various forms.

[0079] As shown in (a) of Fig. 11, when backlight is generated on the first stereo camera (120a), the home plate equipped with the strike zone judgment function according to the present invention can track the trajectory of the baseball using the second stereo camera (120b) and the third stereo camera (120c) positioned at different angles.

[0080] In addition, as shown in (b) of FIG. 11, when backlight is generated on the third stereo camera (120c), the home plate equipped with the strike zone judgment function according to the present invention can track the trajectory of the baseball using the first stereo camera (120a) and the second stereo camera (120b) positioned at different angles.

[0081] As seen, the present invention is characterized in that it is implemented so as to be able to determine whether a ball thrown by a pitcher passes through the strike zone of the home plate by embedding a stereo camera inside the home plate body, thereby determining whether it is a strike or a ball and displaying the status.

[0082] The present invention has the advantage of being able to measure and provide various information, such as the speed, trajectory and spin rate of a baseball, the bat speed when a batter swings, the trajectory of the bat, the speed and launch angle of the batted ball, using images captured from a stereo camera.

[0083] In addition, according to the present invention, there is an effect of being able to deal with a situation where it is impossible to recognize the trajectory of a baseball due to backlight by placing a plurality of stereo cameras at various angles.

Claims

1. For the home plate used in baseball games, Home plate body; A stereo camera unit built into the interior of the home plate body; A control unit that determines whether a baseball passes through the strike zone by using an image captured and transmitted from the stereo camera unit when the baseball passes near the home plate main body; and A home plate having a strike zone judgment function, characterized by including a light-emitting part provided in the home plate main body.

2. In paragraph 1, A home plate having a strike zone judgment function, characterized in that it further includes a power supply unit that supplies power to the stereo camera unit, the control unit, and the light emitting unit.

3. In the second paragraph, the power supply unit A home plate having a strike zone judgment function, characterized in that it is connected to AC power or implemented in the form of a battery while being embedded in the home plate body.

4. In the first paragraph, the light emitting part If the baseball is judged to have passed through the strike zone, the first color is emitted. If the baseball is judged not to have passed the strike zone, the second color is emitted. A home plate having a strike zone judgment function characterized by emitting a third color when an abnormality occurs in the home plate body.

5. In the first paragraph, the stereo camera part A home plate having a strike zone judgment function, characterized by including at least two stereo cameras.

6. In the fifth paragraph, the control unit A home plate having a strike zone judgment function, characterized in that it is possible to three-dimensionally measure the speed of the baseball, the rotational speed of the baseball, and the trajectory of the baseball using images captured by at least two stereo cameras.

7. In the 6th paragraph, the control unit A home plate having a strike zone judgment function, characterized in that it is possible to three-dimensionally measure the speed of the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat using images captured using at least two stereo cameras when a batter swings the bat.

8. In the 7th paragraph, the control unit A home plate equipped with a strike zone judgment function, characterized in that information regarding the speed of the baseball, the rotational speed of the baseball, the trajectory of the baseball, the speed of the bat, the trajectory of the bat, the speed of the ball hit by the bat, and the launch angle of the ball hit by the bat can be transmitted to a user's smart device through an app.

9. In the first paragraph, the strike zone is A home plate equipped with a strike zone judgment function that can be set differently depending on the batter's height.

10. In the first paragraph, the surface of the home plate body is A home plate equipped with a strike zone judgment function, characterized in that it is formed of a material that can protect the light-emitting part, the stereo camera part, and the control part and prevent injuries to players.

11. In the fifth paragraph, the stereo camera part A home plate equipped with a strike zone judgment function, characterized by having a plurality of stereo cameras positioned at various angles so as to be able to recognize the trajectory of the baseball even when backlighting occurs.

12. In the fifth paragraph, the control unit A home plate having a strike zone judgment function, characterized in that when backlight is incident on some of the at least two stereo cameras, an image captured using a stereo camera other than the stereo camera to which the backlight is incident is used.

Images