Method of determining spin of moving ball, and virtual golf device and virtual golf system using the same

Abstract

To provide a method of determining spin of a moving ball, and a virtual golf device and a virtual golf system using the same.SOLUTION: A method of determining spin of a moving ball includes: an image acquisition step of acquiring, at a first time point, a first image for a ball that is provided with an identification part and is moving with a spin, and acquiring a second image at a second time point; an identification information acquisition step of acquiring first identification information of the identification part from the first image, and acquiring second identification information of the identification part from the second image; and a spin determining step of, after selecting an expected spin using cumulative spin data, determining the spin of the moving ball by applying the expected spin to the first and second identification information.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for grasping the spin of a moving ball, and a virtual golf device and a virtual golf system that utilize the same. [Background technology]

[0002] Recently, golf has become more popular, and the number of people playing golf is increasing. Golf is not only played on outdoor golf courses, but screen golf (virtual golf), which allows players to play golf using virtual golf devices, is also becoming more popular. In screen golf, images of a golf course are displayed on a screen, giving the player the feeling of playing a real game outdoors. In addition, screen golf saves time and money compared to playing on an outdoor field, so it is popular among modern people who find it difficult to play on an outdoor field due to time or financial reasons.

[0003] Comparing screen golf with real golf, screen golf has the advantage of being able to provide users with technical services that are difficult to provide in real golf, which is played in an open outdoor space, since screen golf is played in a closed indoor space. For example, in real golf, when a user hits a golf ball, the physical state of the golf ball, such as the speed and launch angle of the hit golf ball, cannot be grasped, but in screen golf, the physical state of the hit golf ball can be grasped and provided to the user using various sensing means. One of the physical states of the golf ball that users are interested in is the "spin" of the golf ball. Spin indicates the rotation state of a golf ball rotating in a three-dimensional space, and in order to sense it, equipment such as an expensive sensor is required. However, since using expensive equipment to sense spin is economically inefficient, there is a need to develop a technology that can accurately grasp the spin at a low cost. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a method for grasping the spin of a moving ball, which can sense the spin in a simple manner without expensive equipment. Another object of the present invention is to provide a virtual golf device that allows a user to sense the spin of a golf ball hit in a simple manner without expensive equipment. Another object of the present invention is to provide a virtual golf system that allows a user to sense the spin of a golf ball hit in a simple manner without expensive equipment. Other objects of the present invention will become apparent from the following description and the accompanying drawings. [Means for solving the problem]

[0005] In order to achieve the above object, a method for grasping the spin of a moving ball according to an embodiment of the present invention includes an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point for a ball having an identifier and moving with a spin, an identification information acquiring step of acquiring first identification information of the identifier from the first image and acquiring second identification information of the identifier from the second image, and a spin grasping step of selecting a predicted spin using accumulated spin data and applying the predicted spin to the first and second identification information to grasp the spin of the moving ball.

[0006] In the method for grasping the spin of a moving ball, the ball is a golf ball, and when a user hits the golf ball with a golf club, the golf ball moves with a spin, and the cumulative spin data can be formed using information on the spin of the golf ball when the user who hit the golf ball whose spin is to be grasped and another user having the same level of golfing skill as the user have hit the golf ball in the past.

[0007] In the method for grasping the spin of a moving ball, the ball is a golf ball, and when a user hits the golf ball with a golf club, the golf ball moves with a spin, and the method further includes a step of sensing a state change due to the movement of the golf ball between the first and second time points, and the cumulative spin data may be formed using the selected spin data after selecting spin data associated with the state change of the golf ball. In the method for grasping the spin of a moving ball, in the spin grasping step, a result of applying the predicted spin to the first identification information is compared with the second identification information, and the predicted spin is determined as the spin of the moving ball according to a comparison result with the second identification information, or a new predicted spin is selected and the spin grasping step is re-executed.

[0008] In the method for grasping the spin of a moving ball, the cumulative spin data may indicate a Gaussian distribution, and the predicted spin may be selected as a plurality of predicted spins by extracting a plurality of arbitrary spins at different positions from each other in the Gaussian distribution. In the method for grasping the spin of a moving ball, the cumulative spin data may exhibit a Gaussian distribution, and the predicted spin may be initially selected in the Gaussian distribution in a range between -standard deviation and +standard deviation centered on the mean.

[0009] In the above method for grasping the spin of a moving ball, the new predicted spin is selected such that the difference between the predicted spin and the new predicted spin increases as the result of comparing the application result of the predicted spin to the first identification information with the second identification information increases. The method for determining the spin of a moving ball further includes additional steps including the steps of acquiring a third image of the ball at a third time point, acquiring third identification information of the identification unit from the third image, and verifying the determined spin using the third identification information.

[0010] In the above method for grasping the spin of a moving ball, a plurality of spins are grasped in the spin grasping step, and a result of applying the plurality of spins to the first identification information or the second identification information is compared with the third identification information, and one of the plurality of spins is determined as the spin of the moving ball according to a comparison result with the third identification information, or a new predicted spin is selected and the spin grasping step and the additional step are re-executed.

[0011] A virtual golf device according to an embodiment of the present invention includes a calculation unit that performs a calculation process to calculate a movement of a virtual golf ball corresponding to the real golf ball when a user hits the real golf ball, and a display unit that displays a virtual golf course and the virtual golf ball moving on the virtual golf course as calculated in the calculation process. After a user hits the real golf ball, the virtual golf device grasps the spin of the moving ball according to a method for grasping the spin of the moving ball, the method including: an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point for a ball having an identifier and moving with a spin; an identification information acquiring step of acquiring first identification information of the identifier from the first image and acquiring second identification information of the identifier from the second image; and a spin grasping step of selecting a predicted spin using accumulated spin data and then applying the predicted spin to the first and second identification information to grasp the spin of the moving ball. In the virtual golf device, the calculation process may reflect the result of grasping the spin of the actual golf ball.

[0012] A virtual golf system according to an embodiment of the present invention includes a service device and at least one virtual golf device communicatively connected to the service device. The virtual golf device includes a calculation unit that performs a calculation process to calculate a movement of a virtual golf ball corresponding to the real golf ball when a user hits the real golf ball, and a display unit that displays a virtual golf course and the virtual golf ball moving on the virtual golf course as calculated in the calculation process. After a user hits the real golf ball, the virtual golf device grasps the spin of the moving ball according to a method for grasping the spin of the moving ball, the method including: an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point for a ball having an identifier and moving with a spin; an identification information acquiring step of acquiring first identification information of the identifier from the first image and acquiring second identification information of the identifier from the second image; and a spin grasping step of selecting a predicted spin using accumulated spin data and then applying the predicted spin to the first and second identification information to grasp the spin of the moving ball.

[0013] In the virtual golf system, the service device includes a storage unit for storing user information, and the user information can be used to form cumulative spin data in the process of grasping the spin of the actual golf ball. Effect of the Invention

[0014] According to the present invention, it is possible to accurately grasp the spin of a moving ball in a simple manner without expensive equipment. [Brief description of the drawings]

[0015] [Figure 1] 1 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to an embodiment of the present invention. [Diagram 2] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Diagram 3] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Figure 4] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Diagram 5] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Figure 6] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Figure 7] 2 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 1. FIG. [Figure 8] 11 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to another embodiment of the present invention. [Figure 9] 9 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 8. FIG. [Figure 10] 9 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 8. FIG. [Figure 11] 9 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 8. FIG. [Figure 12] 9 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 8. FIG. [Figure 13] 9 is a diagram for specifically explaining each step of the operation process of the method for grasping the spin of the moving ball in FIG. 8. FIG. [Figure 14] 11 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to another embodiment of the present invention. [Figure 15] 15A to 15C are diagrams for explaining various methods for forming cumulative spin data used in the method of grasping the spin of a moving ball of FIG. 14. [Figure 16] 15A to 15C are diagrams for explaining various methods for forming cumulative spin data used in the method of grasping the spin of a moving ball of FIG. 14. [Figure 17] 15A to 15C are diagrams for explaining various methods for forming cumulative spin data used in the method of grasping the spin of a moving ball of FIG. 14. [Figure 18] 15A to 15C are diagrams for explaining various methods for forming cumulative spin data used in the method of grasping the spin of a moving ball of FIG. 14. [Figure 19] 11 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to another embodiment of the present invention. [Figure 20] FIG. 2 is a diagram showing a schematic structure of a virtual golf device according to an embodiment of the present invention. [Figure 21] 21 is a diagram showing an example of a method for calculating the movement of a golf ball in the virtual golf device of FIG. 20. [Figure 22] FIG. 21 is a diagram showing an example of a screen display providing golf play information in the virtual golf device of FIG. 20. [Figure 23] FIG. 13 is a diagram showing a schematic structure of a virtual golf device according to another embodiment of the present invention. [Figure 24] 1 is a diagram showing a schematic structure of a virtual golf system according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention will be described in detail below with reference to examples. The objects, features, and advantages of the present invention will be readily understood from the following examples. The present invention is not limited to the examples described herein, and may be embodied in other forms. The examples presented herein are provided so that the disclosed content will be thorough and complete, and so that the concept of the present invention will be fully conveyed to those skilled in the art to which the present invention pertains. Therefore, the present invention should not be limited by the following examples.

[0017] In this specification, the terms "first", "second" and the like are used to describe various elements, but the elements should not be limited by such terms. These terms are merely used to distinguish the elements from each other. Also, when a layer (film) is said to be on another layer (film) or substrate, it means that it can be formed directly on the other layer (film) or substrate, or a third layer (film) can be interposed between them.

[0018] In the drawings, the size of elements or the relative size between elements may be somewhat exaggerated for a clearer understanding of the present invention. In addition, the shapes of the illustrated elements may be somewhat changed due to variations in the manufacturing process, etc. Therefore, unless otherwise specified, the embodiments disclosed in this specification should not be limited to the shapes illustrated, and should be understood to include some modifications.

[0019] FIG. 1 is a flowchart illustrating an example of an operational process of a method for grasping the spin of a moving ball according to an embodiment of the present invention, and FIG. 2 to FIG. 7 are diagrams for specifically explaining each step of the operational process of the method for grasping the spin of a moving ball of FIG. 1. 1, the operational process for determining the spin of a ball includes first to fourth steps (S11-S14): the first step (S11) acquires an image of the ball in motion, the second step (S12) acquires information from the image, the third step (S13) selects an expected spin, and the fourth step (S14) applies the expected spin to the information obtained in the second step (S12) to determine the spin of the ball in motion.

[0020] Referring to FIG. 2, when a ball in motion is moving in the direction of about 2 o'clock while rotating with a spin, in the first step (S11), the ball is photographed at a first time point (T1) to obtain a first image (I1), and the ball is photographed at a second time point (T2) after the first time point (T1) to obtain a second image (I2). The ball includes various types of balls used for sports such as golf balls, baseball balls, table tennis balls, etc., and an identification part (A) is formed on the surface of the ball. The identification part (A) can be said to be a marker formed on the surface of the ball that can be used to grasp the spin state of the ball. For example, a baseball has a number of seams formed so that a pitcher can throw various types of balls, and the spin of the baseball can be grasped by checking the change in the state of the seams of the baseball in motion, so the seams of the baseball can serve as the identification part (A). In addition, most sports balls are marked with the name and brand of the manufacturer that manufactured the ball, and the spin can be grasped through the change in the state of the brand, etc., so these brands, etc. can also act as the identification part (A).

[0021] Referring to FIG. 3, in the second step (S12), first information on the identification portion (A) is obtained from the first image (I1), and second information on the identification portion (A) is obtained from the second image (I2). There are various methods for obtaining ball information from the image of the ball. As an example, the first image (I1) includes parts other than the ball (the place where the ball flies may be included in the image of the ball as the background), and the image is processed to remove such parts other than the ball and extract only the ball and the identification portion (A) on the ball surface, and then the relationship between the ball and the identification portion (A) is analyzed to obtain information on the identification portion (A). The same method can be applied to the second image (I2). Here, the identification information (for convenience, it may be simply named "information"), which is information on the identification portion (A), includes position information of the identification portion (A) on the ball. If the ball has a sphere shape, each point on the surface of the ball has different position information from the center of the sphere. Therefore, the identification part (A) formed on the surface of the sphere can also have specific position information from the center of the sphere, and the position information of the identification part (A) can be obtained by extracting an image of the ball and the identification part (A) and then analyzing the positional relationship between the center of the ball and the identification part (A).

[0022] The first and second identification information of the identification unit (A) are represented by A1 (i1, j1, k1) and A2 (i2, j2, k2), respectively. Here, A1 (i1, j1, k1) and A2 (i2, j2, k2) indicate location information for one point or location information for multiple points. That is, when the identification unit (A) consists of one point, A1 (i1, j1, k1) and A2 (i2, j2, k2) are location information for a single point, and when the identification unit (A) consists of multiple points, A1 (i1, j1, k1) and A2 (i2, j2, k2) are location information for multiple points. Usually, the identification unit (A) is often composed of multiple points rather than a single point.

[0023] Since the ball and the identification part (A) exist in a three-dimensional space, the position information of the identification part (A) is displayed by three independent components that represent three dimensions, and i, j, and k indicate the three independent components. For example, i, j, and k can indicate the x component, y component, and z component in a Cartesian coordinate system. Alternatively, i, j, and k can indicate the r component, φ component, and θ component in a spherical coordinate system. In order to grasp the three-dimensional position information of the identification part (A) from an image of the ball, a stereo camera or a depth camera can be used when photographing the ball. Also, multiple cameras that can obtain three-dimensional information can be used. Alternatively, it is possible to use a camera that generates a two-dimensional image without using a stereo camera or the like. Two-dimensional position information of the identification part (A) can be obtained from an image photographed by a two-dimensional camera. Even if two-dimensional position information is obtained and only position information for the i and j components is obtained among the i, j, and k components in the identification unit (A), if the ball is moving under specific conditions (for example, when the ball's spin value for the above k component is zero or can be almost ignored), the ball's spin can be determined from the two-dimensional position information alone.

[0024] Referring to Fig. 4, it is assumed that a ball has a spin and rotates around a specific axis in a three-dimensional space consisting of i-axis, j-axis, and k-axis. Here, the spin can be specified by an axis that is a reference for the rotation of the ball and a rotation amount that indicates the degree of rotation. For example, when the spin of the ball is "S", this can be expressed as follows with the spin Si of the i-axis component, the spin Sj of the j-axis component, and the spin Sk of the k-axis component. S = Si i + Sj j + Sk k ( i , j , k indicate the fundamental unit vectors of the i-axis, j-axis, and k-axis, respectively) At this time, the rotation amount (S1) and rotation axis (S2) of the spin (S) can be calculated using Si, Sj, and Sk as follows:

number

[0025] The spin of the currently moving ball is the target spin (S * ), the identification unit (A) is located at a first position on the ball at a first time point (T1), and the target spin (S * ) at the second point in time (T2). Thus, the target spin (S * ) serves to change the position of the identification part (A) on the ball and to detect the target spin (S * ) rotation amount (S1 * ) and the rotation axis (S2 * ) and the target spin (S * On the other hand, when the identification portion (A) is represented by multiple points (multiple pixels), the first and second information (A1(i1, j1, k1), (A2(i2, j2, k2)) can be a collection of position information for multiple points. These are called A1set and A2set, and the target spin (S * ) position transformation matrix by Sm * Then, the following equation (1) can be established. [Sm * ][A1set] = [A2set] ------- Equation (1)

[0026] According to formula (1), the first identification information ([A1set]) of the identification unit (A) is assigned a target spin (S * ) according to the position conversion factor ([Sm * Now that the first and second identification information ([A1set], [A2set]) is known, the unknown target spin (S * ) is a situation in which one wishes to grasp the spin of the player currently moving, and according to the embodiment of the present invention, the spin of the player currently moving can be grasped by utilizing the formula (1). Specifically, in this embodiment, an arbitrary spin is assumed, and a position conversion factor according to the arbitrary spin is applied to the formula (1) to check whether the formula (1) holds. If the formula (1) holds, the arbitrary spin is treated as a target spin (S *) and if equation (1) does not hold, a method is used in which a new arbitrary spin is repeatedly assumed until equation (1) holds.

[0027] As described above, in this embodiment, an arbitrary spin is assumed to utilize equation (1), and in this regard, in the third step (S13), the target spin (S *) is selected. Referring to FIG. 5, when selecting the predicted spin, cumulative spin data accumulated for the spin can be used. The cumulative spin data includes data collected from all spins recorded when a plurality of users have played a ball with a spin in the past. For example, assuming that the currently moving ball is a golf ball used in a virtual golf play such as screen golf, the screen golf course is provided with a sensing means such as a laser sensor capable of measuring the spin, and the spin of the hit golf ball can be measured every time all users playing screen golf hit the golf ball by using the sensing means. The measured spin can be stored in a storage device such as a memory or a hard disk provided in the screen golf course. Alternatively, if there are a plurality of screen golf courses and the plurality of screen golf courses are managed by a central server, the measured spin can be stored in a storage device of the central server. In this way, when a spin corresponding to a hit is stored every time a user hits a golf ball, the stored data can be accumulated to form cumulative spin data for all hits of golf balls by all users. When a sufficient amount of data is accumulated, the cumulative spin data can show the shape of a Gaussian distribution curve. As shown in Figure 5, the Gaussian distribution curve is symmetrical around the mean (m), with most of the data concentrated in the range of m-σ (σ is the standard deviation) and m+σ around the mean. In the third step (S13), an arbitrary spin is selected as the predicted spin (denoted as "ES" in Figure 5) from the Gaussian distribution of the cumulative spin data. As an example, the initial predicted spin can be selected at the mean (m) or near the mean (m). The mean (m) indicates the case where the probability of the corresponding spin being obtained is the highest in the cumulative statistics, so when a predicted spin is selected near the mean (m), it is determined whether the selected predicted spin is the spin (target spin (S)) that the golf ball has in motion. * )) is likely to be decided.

[0028] In a fourth step (S14), the predicted spin is applied to the first and second identification information for the identification unit (A) to grasp the spin of the ball during the movement. Specifically, the predicted spin is first applied to the above formula (1) as follows: [ESm][A1set] = [EA2set] ------- Equation (2)

[0029] Here, [ESm] denotes a position transformation matrix according to the predicted spin, [A1set] denotes the first identification information related to the identification unit (A) at the first time point, and [EA2set] denotes the result obtained by applying the predicted spin to the first identification information (for convenience, named "preliminary information"). When the preliminary information is obtained by formula (2), it is compared with the second identification information. If there is a difference between the preliminary information and the second information as a result of comparing the preliminary information and the second information, this means that the predicted spin is the correct spin (target spin (S * )) is not the same as the predicted spin, and a new spin is selected. Here, the difference between the preliminary information and the second information means that the shape of the discrimination unit (A) when the predicted spin is assumed to be applied to the discrimination unit (A) at the first time point (T1) is different from the shape of the discrimination unit (A) at the actual second time point (T2) as shown in FIG. 6. If it is determined that the predicted spin is not the correct spin, a new predicted spin is selected, a position conversion factor according to the new predicted spin is applied to the first information to calculate new preliminary information, and the new preliminary information is compared with the second information to determine whether the new predicted spin is the correct spin. If the preliminary information and the second information are identical or very similar, the selected spin is determined as the target spin of the ball currently moving. Here, the fact that the preliminary information and the second information are very similar means that the difference between [EA2set] and [A2set] is small and is equal to or smaller than a predetermined value (the position information may be + or -, and a small difference here means a small absolute value).

[0030] The accumulated spin data is also used when selecting a new expected spin when it is determined that the initially selected expected spin is not the correct spin. Referring to FIG. 7, the initially selected expected spin is designated as the initial expected spin (ES) for convenience, and the second selected expected spin is designated as the second expected spin (ES', ES"), where the initial expected spin and the second expected spin (ES', ES") can be selected according to a certain rule. For example, the first expected spin (ES) can be selected at the mean (m) or near the mean (m). The mean (m) indicates the case where the probability of the corresponding spin occurring is highest in cumulative statistics, so when the expected spin (ES) is selected at the mean (m) or near the mean (m), the selected expected spin (ES) is likely to be determined as the spin of the golf ball in motion. If the first expected spin (ES) is not the correct spin, a second expected spin (ES', ES") is selected. As the second expected spin (ES', ES"), a spin (ES') having a first difference (Δ1) from the first expected spin (ES) or a spin (ES") having a second difference (Δ2) from the first expected spin (ES) is selected. As described above, when the first expected spin (ES) is applied to the first information regarding the identifier (A), "preliminary information" for the identifier (A) at the second time point (T2) is obtained. If the difference between the "preliminary information" and the second information for the identification part (A) is small, this means that the initial expected spin (ES) is not very different from the correct spin, so it is preferable to select a second expected spin (ES') whose difference from the initial expected spin (ES) is relatively small. If the difference between the "preliminary information" and the second information for the identification part (A) is large, this means that the initial expected spin (ES) is significantly different from the correct spin, so it is preferable to select a second expected spin (ES") whose difference from the initial expected spin (ES) is relatively large.

[0031] FIG. 8 is a flowchart illustrating an example of an operational process of a method for detecting the spin of a moving ball according to another embodiment of the present invention, and FIG. 9 to FIG. 13 are diagrams for specifically explaining each step of the operational process of the method for detecting the spin of a moving ball of FIG. 8. 8, the operation process for determining the spin of a ball includes first to fifth steps (S21-S25). The first step (S21) acquires an image of the ball in motion, the second step (S22) acquires information from the image, the third step (S23) selects an expected spin, the fourth step (S24) applies the expected spin to the information obtained in the second step (S22) to determine the spin of the ball in motion, and the fifth step (S25) verifies the determined spin.

[0032] 9, when a moving ball is moving in a predetermined direction while rotating with a spin, in a first step (S21), the ball is photographed at a first time point (T1) to obtain a first image (I1), the ball is photographed at a second time point (T2) after the first time point (T1) to obtain a second image (I2), and the ball is photographed at a third time point (T3) after the second time point (T2) to obtain a third image (I3). The balls include various kinds of balls used for sports such as golf balls, baseball balls, table tennis balls, etc., and an identification part (A) that is a mark that can be identified from the outside is formed on the surface of the ball.

[0033] Referring to FIG. 10, in the second step (S22), first information on the identifier (A) is obtained from the first image (I1), second information on the identifier (A) is obtained from the second image (I2), and third information on the identifier (A) is obtained from the third image (I3). The ball information can be obtained by removing parts other than the ball from the captured image, extracting only the ball and the identifier (A) on the ball surface, and then analyzing the relationship between the ball and the identifier (A). Here, the identifier information (which may be simply called "information" for convenience) that is information on the identifier (A) includes position information of the identifier (A) on the ball. Specifically, the first to third identifiers are represented as A1 (i1, j1, k1), A2 (i2, j2, k2), and A3 (i3, j3, k3), respectively. Here, A1(i1, j1, k1), A2(i2, j2, k2), and A3(i3, j3, k3) each indicate location information for one point or location information for multiple points.

[0034] In the third step (S23), a predicted spin is arbitrarily selected. Referring to FIG. 11, the accumulated spin data accumulated for the spin can be used in selecting the predicted spin, as in the previous embodiment. The accumulated spin data can be formed by accumulating past records for a plurality of spins, and when a sufficient amount of data is accumulated, the accumulated spin data can show the shape of a Gaussian distribution curve. As shown in FIG. 11, the Gaussian distribution curve has a symmetric shape around the mean (m), and most of the data is concentrated in the range of m-σ (σ is the standard deviation) and m+σ around the mean. In the third step (S23), a single or multiple arbitrary spins are selected from the Gaussian distribution of the accumulated spin data. In the case of a single, the subsequent steps (fourth and fifth steps (S24, S25)) are performed for one predicted spin at a time, and in the case of multiple, the subsequent steps (fourth and fifth steps (S24, S25)) are performed for multiple predicted spins at a time. If the number of times predicted spins are selected until the correct spin is found is very large, it is preferable to select multiple predicted spins at once and perform the subsequent steps for efficient process progress. When multiple expected spins (ES1, ES2, ES3) are selected, they can be selected at any position. Or, they can be selected near the mean (m) or standard deviation (σ) at the time of initial selection. The mean (m) and standard deviation (σ) indicate a case where the probability of the corresponding spin is relatively high in cumulative statistics, so when expected spins (ES1, ES2, ES3) are selected near the mean (m) or standard deviation (σ), there is a high possibility that the selected expected spins (ES1, ES2, ES3) will be determined as the spin of the golf ball in motion.

[0035] In a fourth step (S24), the predicted spin (ES1, ES2, ES3) is applied to the first and second identification information for the identification unit (A) to grasp the spin of the ball during its movement. Specifically, the predicted spin (ES1, ES2, ES3) is first applied to the following equations (3-1), (3-2), and (3-3) as follows: [ES1m] [A1set] = [E1A2set] ------- Formula (3-1) [ES2m] [A1set] = [E2A2set] ------- Formula (3-2) [ES3m] [A1set] = [E3A2set] ------- Formula (3-3)

[0036] For ease of explanation, if the predicted spins (ES1, ES2, ES3) are named the first predicted spin (ES1), the second predicted spin (ES2), and the third predicted spin (ES3), respectively, in the above formula, [A1set] indicates the position information (first information) of the identification unit (A) at the first time point (T1), [ES1m], [ES2m], and [ES3m] indicate position conversion factors by the first to third predicted spins (ES1, ES2, ES3), respectively, [E1A2set] is preliminary information obtained by applying the first predicted spin (ES1) to the first information (named "first preliminary information"), [E2A2set] is preliminary information obtained by applying the second predicted spin (ES2) to the first information (named "second preliminary information"), and [E3A2set] is preliminary information obtained by applying the third predicted spin (ES3) to the first information (named "third preliminary information"). When the first to third preliminary information are obtained, they are compared with the second information. If there is a difference between the first to third preliminary information and the second information as a result of comparing the first to third preliminary information with the second information, the first to third predicted spins (ES1, ES2, ES3) are not all correct spins, so the third step (S23) is executed again. That is, in the third step (S23), a plurality of predicted spins are selected, and this time predicted spins other than the first to third predicted spins (ES1, ES2, ES3) previously selected are selected.

[0037] As shown in FIG. 12, if the first and second preliminary information to which the first and second predicted spins (ES1, ES2) are applied are significantly different from the identifier information (second information ([A2set])) at the second time point (T2), and the third preliminary information to which the third predicted spin (ES3) is applied is identical / similar to the identifier information (second information ([A2set])) at the second time point (T2), the third predicted spin (ES3) is determined to be the spin of the ball currently in motion.

[0038] In the fifth step (S25), the spin determined in the fourth step (S24) is verified using the third information. As shown in Fig. 13, in the fifth step (S25), the third expected spin (ES3) is applied to the second information for the identifier (A) (or the third expected spin (ES3) can be applied to the first information). To this end, the third expected spin (ES3) is applied to the following equation (4) as follows: [ES3m] [A2set] = [E3A3set] ------- Formula (4)

[0039] In formula (4), [ES3m] indicates the position conversion factor according to the third predicted spin (ES3), [A2set] indicates the position information (second information) of the identification unit (A) at the second time point (T2), and [E3A3set] is the result obtained by applying the third predicted spin (ES3) to the second information (named "verification information"). When the verification information is obtained, it is compared with the third information ([A3set]). If there is a difference between the verification information and the third information as a result of comparing the verification information and the third information, the third predicted spin is not the correct spin, so the process returns to the third step (S23) and the step of selecting the predicted spin is executed again. If the verification information and the third information are identical or very similar as a result of comparing the verification information and the third information, the third predicted spin is determined as the spin of the ball currently in motion, and the entire process of grasping the spin is completed. Here, the fact that the verification information and the third information are very similar means that the difference between [E3A3set] and [A3set] is smaller than a predetermined value. The reason for adding this verification step is that there can be multiple spins that transform the identification unit (A) from a state at a first time point (first information state) to a state at a second time point (second information state) (for ease of explanation, to take a simple example in a two-dimensional state, if the identification unit (A) is located at the 9 o'clock direction of the ball at a first time point and at the 12 o'clock direction of the ball at a second time point, the state change between the first time point and the second time point can occur by both a spin in which the ball rotates 90 degrees clockwise and a spin in which the ball rotates 270 degrees counterclockwise), and therefore the spin that the currently moving ball has among the multiple spins can be accurately identified through the verification step.

[0040] FIG. 14 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to another embodiment of the present invention, and FIG. 15 to FIG. 18 are diagrams for explaining various methods for forming cumulative spin data used in the method for grasping the spin of a moving ball of FIG. 14.

[0041] 14, the operation process for grasping the spin of a ball includes first to fifth steps (S31-S35). In the first step (S31), an image of a ball having an identification portion formed on its surface during movement is acquired, in the second step (S32), identification information of the identification portion is acquired from the image, in the third step (S33), one of a plurality of accumulated spin distribution data is selected, in the fourth step (S34), an expected spin is selected using the selected spin distribution data, and in the fifth step (S35), the spin of the ball during movement is grasped using the selected expected spin.

[0042] Looking at each of the first to fifth steps (S31-S35) in detail, in the first step (S31), a ball having an identifier formed on its surface is photographed at a first time point to obtain a first image, and the ball is photographed at a second time point after the first time point to obtain a second image. In the second step (S32), first information on the identifier is obtained from the first image, and second information on the identifier is obtained from the second image. The first and second information include position information of the identifier on the ball. In the third step (S33), a selection step is performed to select one of a plurality of spin distribution data, which will be described later. In the fourth step (S34), a predicted spin is arbitrarily selected using the spin distribution data selected in the third step (S33). The predicted spin may be selected as a single spin or multiple spins. In the fifth step (S35), the single or multiple predicted spins selected in the fourth step (S34) are applied to the first information to obtain preliminary information, and the preliminary information is compared with the second information. If there is a difference between the preliminary information and the second information as a result of comparing the preliminary information and the second information, the predicted spin is not the correct spin, so the process returns to the fourth step (S34) and the fourth and fifth steps (S34, S35) are executed again. Among the first to fifth steps (S31-S35) of this embodiment, the first, second, fourth and fifth steps (S31, S32, S34, S35) correspond to the first to fourth steps (S11, S12, S13, S14) in the embodiment described with reference to Figures 1 to 7, so detailed description of these steps will be omitted.

[0043] Referring to FIG. 15 for the third step (S33), the cumulative spin data is stored in a predetermined storage device. For example, assuming that the ball currently moving is a golf ball used in a virtual golf play such as screen golf, the screen golf course is provided with a sensing means such as a laser sensor capable of measuring the spin, and the spin of the hit golf ball can be measured every time all users playing screen golf hit a golf ball using the sensing means. The measured spin can be stored in a storage device such as a computer memory or hard disk provided in the screen golf course. Alternatively, if there are multiple screen golf courses and the multiple screen golf courses are managed by a central server, the measured spin can be stored in the storage device of the central server. In this way, if the spin due to the corresponding hit is stored every time a user hits a golf ball, the stored data can be accumulated to form cumulative spin data for all hits of the golf ball by the user. Here, the cumulative spin data stored in the storage device can be configured into a plurality of categories according to the golfing ability of the user. For example, the cumulative spin data can be classified into cumulative spin data for ALLUser, which is formed based on spin information of a golf ball hit when all users hit the golf ball while playing at a screen golf course; cumulative spin data for 1LevelUser, which is formed based on spin information of a golf ball hit when a user with a first level golf skill hits the golf ball while playing at a screen golf course; cumulative spin data for 2LevelUser, which is formed based on spin information of a golf ball hit when a user with a second level golf skill hits the golf ball while playing at a screen golf course; and cumulative spin data for 3LevelUser, which is formed based on spin information of a golf ball hit when a user with a third level golf skill hits the golf ball while playing at a screen golf course.The cumulative spin data for ALLUser, the cumulative spin data for 1LevelUser, the cumulative spin data for 2LevelUser, the cumulative spin data for 3LevelUser, etc. show different Gaussian distribution curves. In this way, when the cumulative spin data is divided according to the level of the golf skill of the user, the cumulative spin data for ALLUser can be used when selecting the expected spin as in the above embodiment. Alternatively, when the user who hit the golf ball whose spin is currently to be grasped has a second-class golf skill, the expected spin can be selected using a Gaussian distribution curve based on the data of a user who has the same level of golf skill as the user (the cumulative spin data for 2LevelUser). In this way, by providing a plurality of cumulative spin data divided according to the level of the golf skill of the user, and using the cumulative spin data of a user who has the same or similar golf skill level as the user who hit the golf ball when grasping the spin of the golf ball during exercise, there is an advantage that the time required for the operation of grasping the spin can be shortened.

[0044] Golf skills can be determined by various factors, but hitting accuracy is particularly important. If a golf ball is hit accurately, it will fly straight toward the target point, but if it is not, it is highly likely that the golf ball will deviate to the left or right from the direction toward the target point, resulting in a hook or slice. Golf balls that hook or slice have a larger side spin than those that do not. Therefore, when a user with high hitting accuracy and good golf skills hits a golf ball, the golf ball generally flies forward with a small side spin, whereas when a user with low hitting accuracy and poor golf skills hits a golf ball, the golf ball generally may hook with a large side spin to the left or slice with a large side spin to the right. In addition to hitting accuracy, there are various factors that determine golf skills, such as flying distance and putting. It cannot be said that a hook or slice will necessarily occur just because a golfer has low golf skills, but from a large amount of data accumulated by multiple users, it is clear that there is a certain degree of difference in the distribution of spin data depending on the golf skills. Assume that the spin of all users has a range of (Sa, Sb), and the spin of a user belonging to a particular level has a range of (Sa', Sb') that falls within the range of (Sa, Sb). When the cumulative spin data for ALLUser is used to grasp the spin of a golf ball hit by a user of the particular level, a spin that falls within the range of (Sa, Sb) but is outside the range of (Sa', Sb') may be selected as the expected spin, and this expected spin is highly likely to be incorrect. In this case, the time required for the entire operation increases due to the time required to proceed through the fourth and fifth steps (S34, S35) for the corresponding expected spin. In contrast, when the spin data for the user of the particular level is used instead of the cumulative spin data for ALLUser to grasp the spin of a golf ball hit by a user of the particular level, a spin that falls within the range of (Sa', Sb') may be selected as the expected spin, and this expected spin is highly likely to be correct, at least compared to a spin that falls outside the range of (Sa', Sb').As a result, the time required for the entire operation can be reduced compared to when the accumulated spin data for ALLUser is used.

[0045] The process of selecting specific cumulative spin data from the overall cumulative spin data in the third step (S33) has been described above. In the embodiment described with reference to FIG. 15, the criterion for selecting specific data from the overall data is the "user's golf ability". By applying the same principle, it is also possible to select only specific data from the overall data in the third step (S33) according to other "criterion" other than the "user's golf ability". Hereinafter, the movement characteristics of the ball will be described as an example of another "criterion". As described above, it is assumed that the currently moving ball is a golf ball used in a virtual golf play such as screen golf, and that each time a user hits a golf ball in the virtual golf play, the spin due to the corresponding hit is stored in a storage device, and the stored data is accumulated to form cumulative spin data for all hits of the golf ball by the user. Here, the cumulative spin data stored in the storage device may be composed of a plurality of data divided according to the movement characteristics of the hit golf ball. For example, as shown in FIG. 16, the cumulative spin data can be divided into ALL cumulative spin data formed based on spin information of a hit golf ball when all users hit a golf ball while playing at a screen golf course, NoSideSpin cumulative spin data formed based on spin information when the hit golf ball has a movement characteristic of flying straight ahead with almost no side spin, LeftSideSpin cumulative spin data formed based on spin information when the hit golf ball has a movement characteristic of flying while curving to the left with a left side spin, and RightSideSpin cumulative spin data formed based on spin information when the hit golf ball has a movement characteristic of flying while curving to the right with a right side spin (here, the NoSideSpin cumulative spin data / LeftSideSpin cumulative spin data / RightSideSpin cumulative spin data can be further divided into multiple items according to the size of the side spin).For example, the cumulative spin data for LeftSideSpin can be divided into more items such as a first range of cumulative spin data for LeftSideSpin and a second range of cumulative spin data for LeftSideSpin. As shown in FIG. 16, the ALL cumulative spin data / NoSideSpin cumulative spin data / LeftSideSpin cumulative spin data / RightSideSpin cumulative spin data, etc., show different Gaussian distribution curves. When the cumulative spin data is divided according to the movement characteristics of the hit golf ball, the ALL cumulative spin data can be used in selecting the expected spin as in the above embodiment. Alternatively, it is first detected what state change occurs during the movement of the golf ball whose spin is currently to be grasped, and when the detection result shows that the golf ball has a movement characteristic of flying while curving to the right, the expected spin can be selected using a Gaussian distribution curve based on data (RightSpin cumulative spin data) that matches the movement characteristics. In this way, by providing a plurality of cumulative spin data categorized according to the movement characteristics of a golf ball and using the cumulative spin data associated with the movement characteristics of the golf ball when trying to grasp the spin of the golf ball during movement, there is an advantage that the time required for grasping the spin can be shortened, and the reason for this is the same as that explained in the case of using a plurality of cumulative spin data categorized according to the user's golf skill level (see the related explanation in FIG. 15).

[0046] Although the example in which the cumulative spin data is divided into a plurality of categories according to the characteristics of the path along which the hit golf ball moves has been described above, other criteria may be used in addition to the above movement characteristics. For example, the cumulative spin data may be divided into a plurality of categories according to the launch speed or launch angle of the hit golf ball. In addition, the variables for the motion characteristics such as the movement characteristics / launch speed / launch angle may be based on only one of these, and the cumulative spin data may be composed of a plurality of cumulative spin data. Alternatively, the cumulative spin data may be composed of a plurality of cumulative spin data based on at least two or more of the various variables. When two or more composite variables are applied, the two or more composite variables of the hit golf ball are identified, and the cumulative spin data of the items that match the composite variables are selected, and then the predicted spin may be selected from the selected cumulative spin data.

[0047] In the embodiment described with reference to Figures 15 and 16, the cumulative spin data is composed of a plurality of data divided according to a specific criterion, but it is not necessary to prepare a plurality of cumulative spin data separately in advance. The cumulative spin data corresponding to the "specific criterion" used in selecting the expected spins can be generated immediately before selecting the expected spins. This will be described with reference to Figures 17 and 18.

[0048] Assuming that a golf ball is used in a virtual golf play such as screen golf as described above, a record of a user playing screen golf is stored in a storage device such as a computer memory or a hard disk provided in a virtual golf device of a screen golf course. Alternatively, if there are multiple screen golf courses and the multiple screen golf courses are managed by a central server, the user's play record is stored in the storage device of the central server. Referring to FIG. 17, the storage device is divided into multiple storage areas, and each of the multiple storage areas stores a play record of a different user. The storage area stores a play score recorded by the user, information on the state of the golf ball such as spin and flight distance when the user hits, and personal records of the user such as average number of strokes / average flight distance / fairway landing rate. In addition, the storage area stores information on the level of the user's golf skill. Here, the user's golf skill can be determined using various play information when the user played in the past. For example, the user's golf skill can be determined using the "average number of strokes". The average number of strokes usually means the average number of strokes when playing 18 holes on a golf course consisting of 18 holes. In golf, the total number of strokes required for 18 holes is 72, and the lower the number of strokes a user records in 18 holes, the better the golfing ability. Professional golfers record strokes in their 60s or early 70s, while average golfers can be said to be advanced if they are within 80 strokes, and whether a user records a double-digit number of strokes or a triple-digit number of strokes based on the standard of 100 strokes can determine whether they are a beginner or not. In this way, the average number of strokes is an example of an index for judging the level of a user's golfing ability, and users who have the same average number of strokes as the user or users whose average number is slightly different from the user's by about a few strokes can all be judged to have the same level of golfing ability.

[0049] Assume that a user with second-class golf ability is playing a golf ball and the spin of the golf ball hit by the user is grasped. According to the embodiment described with reference to FIG. 14 and FIG. 15, a Gaussian distribution curve consisting of spin distribution data for a user having the same golf ability as the user playing the golf ball is selected from a plurality of spin distribution data, and an expected spin is selected from the Gaussian distribution curve. However, according to the present embodiment, a Gaussian distribution curve for a user having the same golf ability as the user playing the golf ball is not separately provided. In the present embodiment, as shown in FIG. 17, spin information (S1, S3, S4) of the currently playing user and users (User1, User3, User4) having the same golf ability as the user playing the golf ball is extracted from an area storing play records of these users (User1, User3, User4), and then cumulative spin data having a Gaussian distribution curve is generated based on the extracted spin information. In this way, the cumulative spin data of a user having a specific golf ability can be generated immediately before the step of selecting an expected spin, and in this case, it is not necessary to generate and separately store a plurality of cumulative spin data according to the user's golf ability in advance.

[0050] When data matching the "specific criteria" are extracted and then collected to generate cumulative spin data before selecting an expected spin, the "specific criteria" may be other than the golfing ability of the user. For example, it may be the motion characteristics of the ball. Assuming a golf ball used in a virtual golf play such as screen golf as described above, a record of a user playing screen golf is stored in a storage device provided in a virtual golf device of a screen golf course or a central server managing a plurality of screen golf courses. Referring to FIG. 18, the storage device is divided into a plurality of storage areas, and each of the plurality of storage areas stores a record of a physical state of a golf ball hit by a user after hitting the golf ball. For example, the storage area stores information on the state of a golf ball such as the moving speed, moving direction, spin, launch angle, etc. of the hit golf ball when the user hits the golf ball, classified for each hit case of the user. The cumulative spin data for selecting an expected spin may be formed based on the extracted information after extracting some information matching the motion characteristics of a golf ball currently moving from information stored in the storage device. For example, as shown in FIG. 18, it is assumed that a storage area for storing the physical state of a golf ball hit by a user is divided into a plurality of areas, and each of the plurality of storage areas stores information on the motion characteristics of the golf ball (e.g., the golf ball flies straight ahead without curving, the golf ball flies slightly curving to the right, the golf ball flies greatly curving to the right, etc.) and the spin when the corresponding motion characteristics are present. It is also assumed that the golf ball currently hit by the user exhibits a movement characteristic of flying while curving to the right. In this case, if Motion 1, Motion 2, and Motion 5 are cases in which the golf ball exhibits the motion characteristics of curving to the right, and Motion 3 and Motion 4 are cases unrelated to the motion characteristics of the golf ball curving to the right, in the storage device, spin information (S1, S2, S5) when the motion characteristics of Motion 1, Motion 2, Motion 5, etc. are present can be extracted, and then cumulative spin data having a Gaussian distribution curve can be generated based on the extracted spin information.In this manner, the cumulative spin data for a case showing a specific motion characteristic can be generated immediately before the step of selecting the predicted spin. In this case, it is not necessary to prepare and separately store a plurality of cumulative spin data corresponding to the motion characteristics of the golf ball in advance.

[0051] FIG. 19 is a flowchart illustrating an example of an operation process of a method for grasping the spin of a moving ball according to another embodiment of the present invention. 19, the operation process for grasping the spin of a ball includes first to sixth steps (S41-S46). In the first step (S41), an image of the ball in motion is acquired, in the second step (S42), information is acquired from the image, in the third step (S43), one of a plurality of spin distribution data is selected, in the fourth step (S44), a predicted spin is selected using the selected spin distribution data, in the fifth step (S45), the predicted spin is applied to the information acquired in the second step (S42) to grasp the spin of the ball in motion, and in the sixth step (S46), the grasped spin is verified.

[0052] Comparing this embodiment with the embodiment described with reference to Figures 14 to 18, this embodiment differs in that the number of images and identification part information acquired in the first and second steps (S41, S42) is increased by one, and a step of verifying the spin is added in the sixth step (S46). That is, the difference between this embodiment and the previous embodiment is that a third image is further generated and used for spin verification, which corresponds to the first, second, and fifth steps (S21, S22, S25) in the embodiment described with reference to Figures 8 to 13. Therefore, this embodiment can be considered as a combination of the embodiment described with reference to Figures 8 to 13 and the embodiment described with reference to Figures 14 to 18, and the detailed description of each step constituting this embodiment will be omitted since it can be fully understood from the description of the corresponding step in the previous embodiment.

[0053] In this embodiment, too, it is possible to select cumulative spin data that matches specific requirements (user's golfing ability, golf ball kinetic characteristics, etc.) related to the golf ball currently in motion using stored information such as shown in Figures 15 and 16, and to select a predicted spin using this. Alternatively, in this embodiment, too, it is possible to extract spin data for cases that satisfy specific requirements (user's golfing ability, golf ball kinetic characteristics, etc.) using stored information such as shown in Figures 17 and 18, and then generate cumulative spin data using the extracted data, and to select a predicted spin using the generated cumulative spin data. Various methods for grasping the spin of a moving ball have been described above, and the above-described methods for grasping the spin can be applied to various devices. Grasping the spin is necessary for sports devices such as golf, baseball, soccer, etc., and the need for it increases especially when a user plays a virtual sport indoors. Below, a virtual golf device will be described as an example of a sports device that uses the action of grasping the spin.

[0054] FIG. 20 is a diagram showing a schematic structure of a virtual golf device according to an embodiment of the present invention, FIG. 21 is a diagram showing an example of a method for calculating the movement of a golf ball in the virtual golf device of FIG. 20, and FIG. 22 is a diagram showing an example of a screen for providing golf play information in the virtual golf device of FIG. 20. Referring to FIG. 20, a virtual golf device according to an embodiment of the present invention includes a hitting plate (10), a control unit (20), a sensing unit (30), an input unit (40), a sound unit (50), and a display unit (60).

[0055] The striking plate 10 is an area where a user stands to strike a golf ball. The striking plate 10 may be a separately provided plate-like object, or may be a floor where a virtual golf device is installed and where the user stands, rather than a separate object. Although not shown in the drawings, the striking plate 10 is provided with a striking mat on which a golf ball to be struck is placed, and the striking mat is provided with an auto tee that is structured to be movable up and down. A golf ball to be struck can be automatically provided to the user through the auto tee.

[0056] The control unit 20 controls the overall operation among the components of the virtual golf device. For example, the control unit 20 controls an auto tee installed on a hitting mat so that the auto tee provides a golf ball for hitting according to the time when the user hits the ball. For example, immediately after the user hits a golf ball placed on the hitting mat, the control unit 20 detects that the hit has been made and can cause the auto tee to provide a golf ball for the next hit.

[0057] The control unit 20 includes a calculation unit 21, a spin calculation unit 22, and a storage unit 23. The calculation unit 21 performs a calculation process to calculate a trajectory of a golf ball hit by a user when the golf ball moves on an actual golf course in a physical state based on the physical state of the golf ball. The spin calculation unit 22 serves to calculate the spin of the golf ball hit by a user, and the spin calculation process can use the method described above with reference to Figs. 1 to 19, etc., thereby making it possible to accurately grasp the spin of the golf ball in a simple manner without equipment such as an expensive sensor. The spin calculation unit 22 can be configured separately from the calculation unit 21 that calculates the trajectory of the golf ball, but it is also possible to configure the calculation unit 21 to calculate the spin without the spin calculation unit 22, as shown in the drawings. The storage unit 23 includes a storage device such as a memory or a hard disk, and stores various programs and / or data required for the operation of the control unit 20, the calculation unit 21, the spin calculation unit 22, etc. The user's play record and / or cumulative spin data used for spin calculation are stored in the storage unit 23. Alternatively, the calculation unit 22 may have its own storage means, and the user's play record and / or cumulative spin data used for spin calculation may be stored in the storage means.

[0058] The sensing unit 30 senses the movement of the golf club and / or the movement of the golf ball hit by the user when hitting the golf ball, and obtains information required for the calculation process. The sensing unit 30 may use a sensing means such as a camera or a sensor that can capture the movement of the golf club or the golf ball. The sensing means may use various sensing methods such as image sensing, light emission / reception sensing, and laser sensing, and such sensing methods may be used to obtain status information of the golf club or the golf ball hit by the user. The camera or the sensor may be used alone or together, and may be used alone or in combination. Information sensed by the sensing unit 30 is transmitted to the control unit 20, and the calculation unit 21 of the control unit 20 performs a calculation process based on the information from the sensing unit 30. In addition, in order for the spin calculation unit 22 to obtain the spin of the hit golf ball, an image of the golf ball hit by the user at a specific time is required, and when a camera is used as the sensing unit 30, the image may be generated by the sensing unit 30. In this case, the sensing unit 30 performs both an operation of obtaining information for trajectory calculation and an operation of obtaining information for spin calculation. Here, the operation of obtaining information for spin calculation may include an operation of detecting the motion characteristics of the golf ball, such as the translational motion of the golf ball or the moving path of the golf ball. The operation of detecting the motion characteristics of the golf ball is necessary when grasping the spin by applying the method according to the embodiment described with reference to FIG. 16 or FIG. 18. If the sensing unit 30 cannot perform the operation of obtaining information for spin calculation, it may be configured to have a separate camera for that operation.

[0059] The input unit 40 is for receiving various information from the user, and may use a keyboard, mouse, touch screen, etc. When login is required to use the virtual golf device, the user may use the input unit 40 to input his / her ID and password for login, or to select the golf course he / she wants to play or the difficulty level of play, etc. The sound unit 50 includes audio equipment such as a speaker, through which the user is informed of the progress of the game and various sound effects are reproduced according to the progress of the game.

[0060] The display unit 60 includes devices for display operations such as a projector and a screen. The projector projects golf-related images onto the screen so that the golf course and golf balls are displayed on the screen, and the screen displays the projected golf-related images and provides them to the user. Although not shown in the drawings, the display unit 60 may further include a display device such as a kiosk that serves as an auxiliary display in addition to the screen.

[0061] In this specification, some objects displayed on the screen may be referred to with the term "virtual." This is to avoid confusion with objects that exist in the real world, and means that they do not exist in the real world but are displayed in an image on the screen. For example, a "virtual golf course" means a golf course displayed on the screen, and a "virtual golf ball" means a golf ball displayed on the screen.

[0062] The virtual golf device is a device that is installed at a screen golf course to enable a user to play screen golf. The operation process of the virtual golf device when a user plays screen golf is as follows. When a user hits a golf ball, the sensor unit (30) senses the movement of the golf club and the physical state of the golf ball hit by the user, such as the moving speed and moving direction. The information sensed by the sensor unit (30) is transmitted to the control unit (20), and the calculation unit (21) in the control unit (20) performs a calculation process to calculate the trajectory of the golf ball based on the transmitted information. The display unit (60) displays an image of the virtual golf ball moving according to the trajectory calculated by the calculation process, and at this time, the virtual golf ball moves according to the calculated trajectory and lands at a specific point on the virtual golf course displayed on the screen, and the user continues the next shot from the point where the virtual golf ball landed. The above operation process is repeated for the user's next shot.

[0063] The calculation unit 21 may use various methods to calculate the trajectory of the golf ball. In one of the various methods, the calculation unit 21 may detect a parameter value indicating the physical state of the golf ball after hitting and calculate the trajectory from the parameter value. Referring to FIG. 21, examples of the parameters include the speed (V) of the golf ball, the horizontal angle (φ) indicating the direction of the golf ball on the horizontal plane when the golf ball flies due to the hit, the launch angle (θ) indicating the angle at which the golf ball is tilted with respect to the horizontal plane, and the spin (S) indicating the rotation state of the golf ball. The trajectory of the golf ball can be calculated by applying a calculation model using physical laws based on the parameters such as the speed (V), the horizontal angle (φ), the launch angle (θ), and the spin (S). Among the physical parameters, the spin (S) can be obtained by analyzing a plurality of images of the golf ball captured while the hit golf ball is flying by the spin calculation unit 22, etc., and the process of calculating the trajectory of the golf ball can be performed by reflecting the spin obtained after the spin is obtained. Although not shown in the drawings, it is also possible to sense not only the physical state of the golf ball but also the movement of the golf club when the user hits the golf ball and calculate the trajectory of the golf ball using the sensed information about the golf club. After a user hits a golf ball, information sensed about the physical state of the hit golf ball may be displayed on a screen. Referring to FIG. 22, while the user is playing golf, the screen displays the golf course the user is playing on, and one end of the screen displays information grasped about the physical state of the hit golf ball. For example, information grasped about the speed, spin, launch angle, etc. of the golf ball hit by the user may be displayed on the screen. Regarding spin, what the user is interested in is side spin and back spin that affect the trajectory of the golf ball, so the side spin and back spin may be displayed separately on the screen. The side spin indicates a spin component in the left and right directions with respect to the flight direction of the golf ball during the spin of the golf ball, and the side spin may affect the path along which the golf ball flies. Also, the back spin indicates a spin component in the opposite direction to the flight direction of the golf ball during the spin of the golf ball, and the back spin may affect the flight distance of the golf ball.

[0064] FIG. 23 is a diagram showing a schematic structure of a virtual golf device according to another embodiment of the present invention. Referring to FIG. 23, the virtual golf device according to the present embodiment includes a plurality of booths (101, 102, 103). Each booth (101, 102, 103) is configured identically. For example, the first booth (101) includes a hitting plate (101a), a computer device (101b) that includes a kiosk screen and can function as a control device in the above embodiment, a screen (101c), etc., and the other booths (102, 103) also have the same components. Although not shown in the drawing, each booth (101, 102, 103) is further equipped with other devices such as a camera for detecting the movement of the golf club / golf ball when hitting. In each booth (101, 102, 103), multiple users can take turns playing golf. Alternatively, in each booth (101, 102, 103), a single user can play solo while being separated from users in other booths. The virtual golf device according to this embodiment is provided with the spin calculation unit in the above-described embodiment, and the spin calculation unit can grasp the spin of the golf ball hit by the user using the method described with reference to FIGS. 1 to 19, etc.

[0065] FIG. 24 is a diagram showing a schematic structure of a virtual golf system according to an embodiment of the present invention. Referring to Fig. 24, the virtual golf system includes a virtual golf device 100 and a service device 200. The virtual golf device 100 may be one as shown in Figs. 20 to 23. The virtual golf device 100 is installed in a home or public screen golf course where screen golf can be played, and when there are multiple screen golf courses, a virtual golf device 100 is installed in each screen golf course, so that a total of multiple virtual golf devices 100 are provided. The virtual golf device 100 is equipped with the spin calculation unit in the above-mentioned embodiment, and the spin calculation unit can grasp the spin of a golf ball hit by a user using the method described with reference to Figs. 1 to 19.

[0066] The virtual golf device 100 is connected to the service device 200 via a wired or wireless communication network. The service device 200 includes a central server used by a service provider operating a plurality of screen golf courses to manage the virtual golf devices 100 installed in the plurality of screen golf courses. When a user who wishes to use a screen golf service logs in to receive the service, the service device 200 confirms the user's identity and determines whether or not to approve the login. For the login operation, the service device 200 includes a storage unit 210, which stores information for confirming the user's identity. The storage unit 210 also stores various other information in addition to the information for confirming the user's identity. As the other information, the storage unit 210 stores the user's play record information, cumulative spin data used in calculating spin and / or information for forming cumulative spin data (for example, the storage unit 210 may include the storage devices illustrated in FIGS. 15 to 18). As various user information, spin information, etc. are stored in the storage unit (210) in this manner, a plurality of virtual golf devices (100) connected to the service device (200) via wired and / or wireless connections can use the information stored in the storage unit (210), and each virtual golf device (100) does not need to separately store user information, spin data information, etc.

[0067] Specific examples of the present invention have been discussed above. Those skilled in the art will understand that the present invention can be embodied in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than restrictive sense. The scope of the present invention is defined in the claims, not in the above description, and all differences within the scope of the claims should be interpreted as being included in the present invention. [Explanation of symbols]

[0068] 10: Striking plate 20: Control unit 30: Sensing part 40: Input section 50: Sound section 60: Display section 100: Virtual golf device 200: Service equipment

Claims

1. an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point with respect to a ball having an identification unit and moving with a spin; an identification information acquiring step of acquiring first identification information of the identification part from the first image and acquiring second identification information of the identification part from the second image; a spin determination step of determining a predicted spin by using the accumulated spin data and then applying the predicted spin to the first and second identification information to determine the spin of the moving ball. include How to understand the spin of a moving ball.

2. The ball is a golf ball, and when a user hits the golf ball with a golf club, the golf ball moves with a spin, 2. The method of claim 1, wherein the cumulative spin data is formed using information about the spin of a golf ball when the user who has hit the golf ball whose spin is to be currently understood and other users who have the same level of golfing ability as the user have hit the golf ball in the past.

3. The ball is a golf ball, and when a user hits the golf ball with a golf club, the golf ball moves with a spin, sensing a change in state due to motion of the golf ball between the first and second points in time; 2. The method of claim 1, wherein the cumulative spin data is generated by selecting spin data associated with a change in state of the golf ball and then using the selected spin data.

4. 4. The method for grasping the spin of a moving ball according to claim 1, wherein in the spin grasping step, a result of applying the predicted spin to the first identification information is compared with the second identification information, and the predicted spin is determined as the spin of the moving ball according to a comparison result with the second identification information, or a new predicted spin is selected and the spin grasping step is re-executed.

5. the cumulative spin data exhibits a Gaussian distribution; The method of claim 4, wherein the predicted spin can be selected from a plurality of predicted spins by extracting a plurality of arbitrary spins at different positions from each other in the Gaussian distribution.

6. the cumulative spin data exhibits a Gaussian distribution; 5. The method of claim 4, wherein the expected spin can be initially selected in the Gaussian distribution in a range between - standard deviation and + standard deviation around a mean.

7. 5. The method of claim 4, wherein the new predicted spin is selected such that the difference between the predicted spin and the new predicted spin increases as the result of comparing the application result of the predicted spin to the first identification information with the second identification information increases.

8. 4. The method of claim 1, further comprising the steps of: acquiring a third image of the ball at a third time point; acquiring third identification information of the identification portion from the third image; and verifying the determined spin using the third identification information.

9. The spins grasped in the spin grasping step are multiple, 9. The method for grasping the spin of a moving ball according to claim 8, further comprising: comparing a result of applying the plurality of spins to the first identification information or the second identification information with the third identification information; and determining one of the plurality of spins as the spin of the moving ball according to a comparison result with the third identification information, or re-performing the spin grasping step and the additional step while selecting a new predicted spin.

10. a calculation unit for performing a calculation process of calculating a motion of a virtual golf ball corresponding to the actual golf ball when a user hits the actual golf ball; a display unit that displays a virtual golf course and a virtual golf ball that moves on the virtual golf course as calculated in the calculation process; Including, After the user hits the actual golf ball, an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point with respect to a ball having an identification unit and moving with a spin; an identification information acquiring step of acquiring first identification information of the identification part from the first image and acquiring second identification information of the identification part from the second image; a spin determination step of determining a predicted spin by using the accumulated spin data and then applying the predicted spin to the first and second identification information to determine the spin of the moving ball. The spin of the actual golf ball is grasped according to a method for grasping the spin of a moving ball, the method including: Virtual golf equipment.

11. The virtual golf device according to claim 10, wherein the calculation process reflects a result of grasping the spin of the actual golf ball.

12. A service device; at least one virtual golf device communicatively connected to the service device; Including, The virtual golf device comprises: a calculation unit for performing a calculation process of calculating a motion of a virtual golf ball corresponding to the actual golf ball when a user hits the actual golf ball; a display unit that displays a virtual golf course and a virtual golf ball that moves on the virtual golf course as calculated in the calculation process; Including, In addition, in the virtual golf device, after the user hits the actual golf ball, an image acquiring step of acquiring a first image at a first time point and acquiring a second image at a second time point with respect to a ball having an identification unit and moving with a spin; an identification information acquiring step of acquiring first identification information of the identification part from the first image and acquiring second identification information of the identification part from the second image; a spin determination step of determining a predicted spin by using the accumulated spin data and then applying the predicted spin to the first and second identification information to determine the spin of the moving ball. The spin of the actual golf ball is grasped according to a method for grasping the spin of a moving ball, the method including: Virtual golf system.

13. the service device includes a storage unit for storing user information; The virtual golf system of claim 12, wherein the user information can be used to form cumulative spin data in the process of determining the spin of the actual golf ball.

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