JP3025335B2 - Golf hitting training and simulation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf hitting training and simulation method, and more particularly, to analyzing and calculating a flight trajectory of a golf ball in a three-dimensional space at a golf hitting range (practicing range) by electro-optical measurement. And a method for instantly reproducing and displaying an image of the flight trajectory of the golf ball.

[0002]

2. Description of the Related Art Golf hitting ranges (practice ranges) in recent years have been designed with two types of tees, high and low, so that both wood and iron can be practiced. The protective net surrounding the practice area is designed to be large enough to allow players to observe the long flight trajectory of the ball hit by the player to some extent. Therefore, the player can repeat the practice by adding the visual evaluation obtained by the observation to the way of hitting the next ball. For this reason, night training requires sufficient lighting to observe the ball over long distances. In general, players analyze their hitting results,
It simply subjectively evaluates the current hit result without any means to compare the ideal hit result or the previous hit result.

As a means for avoiding this and obtaining an objective evaluation, there is a golf simulation method. Existing golf simulation methods are generally classified into two types. In a first approach, such as Sony's "Birdy Rush System," a golf ball is flexibly coupled to a device having an electromechanical measurement mechanism that allows the system to have an initial impact on the ball, an initial launch angle,
And measure the spin variable of the blow. The flight trajectory of the ball simulated by this measurement is displayed on a video screen together with images of various golf courses. In the second method, for example, a "par-T golf system", an electro-optical device is provided to measure an initial velocity vector of a golf ball actually hit at a large synthetic screen several meters away from the tee. . The spin variables related to slices and hooks are roughly calculated by the angle of return of the ball from the screen. Thus, the simulated flight trajectory is superimposed on the image of the golf course projected on the same screen and is similarly optically projected.

[0004]

However, in any of the above-mentioned conventional simulation methods, the player cannot completely observe the actual flight trajectory of the ball in any case, and therefore, the subjective result of hitting the ball must be realized. There was a problem that there was no way to evaluate. In addition, none of these methods take into account the natural requirements of winds that alter or limit the flight of the ball, so that players cannot compete with such natural requirements, and There was a problem that the dissatisfaction remained as a blow practice.

[0005] Even in the case of a hitting practice area where the actual flight trajectory of the ball can be observed, if the nighttime lighting is insufficient and it is difficult to see a distant ball, it is difficult to identify the ball due to a crowded background. In the case where the installation size of the protective net is not sufficient and the flight of the ball is hindered on the way, there is a problem that the ball cannot be observed to the end. In particular, in this case, there has been a problem that the slices and hooks appearing in the latter half of the flight trajectory cannot be normally sufficiently observed, and therefore cannot be corrected.

SUMMARY OF THE INVENTION It is an object of the present invention to analyze and calculate the flight trajectory of a golf ball in a three-dimensional space by electro-optical measurement and to immediately reproduce and display an image of the flight trajectory of the golf ball. It is an object of the present invention to provide a golf hitting training and simulation method capable of observing the flight trajectory of a ball up to its end point.

[0007]

According to the first aspect of the present invention,
Initial velocity vector determination means for electro-optically observing a golf ball hit and flying from the tee and determining an initial velocity vector of the hit golf ball from the observation result and the tee position; The trajectory of the golf ball flying in a state observable in the observation direction determined based on the initial velocity vector of the golf ball determined by the initial velocity vector determination means is electro-optically tracked to determine the flight trajectory of the golf ball. A first variable calculating means for calculating a variable to be determined, and a flight trajectory of the golf ball determined based on the variable calculated by the first variable calculating means, stored in a memory, and Video reproducing means for immediately reproducing the image of the flight trajectory of the golf ball on a display.
The initial velocity vector determining means may be, for example, a short-time exposure TV.
An overhead imaging unit including a camera and the like, and a processing / control unit including a microprocessor or the like synchronized with the overhead imaging unit, for example. Further, the first variable calculating means includes a ground imaging unit or the like constituted by, for example, a high-resolution CCD-TV camera. Still further, the image reproducing means includes, for example, a frame grabber memory unit, a display monitor unit, and the like.

According to a second aspect of the present invention, in addition to the first aspect of the present invention, a range of a flight trajectory, a wind element, a lateral spin (slice /
A second variable calculating means for calculating a flight trajectory variable of the golf ball including a hook) element, a lift element, and a deterrent element, and using the calculated variables, a flight trajectory of the hit golf ball. And an image superimposing means for superimposing the simulated image of the flight trajectory of the golf ball on the actual or drawn image of the golf course. The second variable calculating means comprises, for example, a microprocessor or the like, and the image superimposing means comprises, for example, a golf course database unit comprising a light desk or the like, a CRT (Ca.
It is composed of a display monitor unit and the like including a thode-ray tube display (cathode ray tube display).

According to a third aspect of the present invention, in addition to the first or second aspect of the present invention, the initial velocity vector determining means is arranged in the tee electro-optically to allow the golf ball to leave the tee. A ball disengagement detecting means for detecting, and a predetermined time axis of the golf ball flying off the tee in correlation with the tee detachment of the golf ball disposed above the tee and detected by the tee detachment detecting means A ball position detecting means for detecting a three-dimensional position, a separation tee position and a separation time of the ball detected by the ball separation detection means, and a predetermined time of the ball detected by the ball position detection means An initial velocity vector comprising a velocity and an ejection angle of the hit and flying ball is determined from the three-dimensional position in the axis. The ball detachment detecting means is constituted by a trigger unit comprising, for example, a light source, an optical sensor, a trigger circuit and the like. The ball position detecting means is constituted by, for example, an overhead imaging unit comprising two CCD line scanning cameras synchronized with the trigger unit. It consists of.

The invention according to a fourth aspect of the present invention, in addition to the means according to the first, second or third aspect of the invention, further includes the above-mentioned means for deficient lighting at a long distance, poor identification with a background, and obstruction of flight by a protective net. The flight trajectory of the hit golf ball, for which the calculation of the variable by the first variable calculating means has become impossible, is based on the variable calculated by the second variable calculating means. It is characterized by having a flight trajectory extrapolating means for extrapolating the trajectory. The above-mentioned flight trajectory extrapolation means comprises, for example, a microprocessor or the like having a built-in extrapolation algorithm.

[0011]

According to the first aspect of the present invention, the golf ball hitting and flying from above the tee is observed electro-optically, and the initial velocity vector of the flying golf ball is determined from the observation result and the tee position. You. Then, the trajectory of the flying golf ball is electro-optically tracked based on the initial velocity vector, and a variable that determines the flight trajectory of the golf ball is calculated. The flight trajectory of the golf ball determined based on this variable is stored in the memory, and the image of the stored flight trajectory is immediately reproduced on the display.
As a result, the impact result can be objectively evaluated.

According to the second aspect of the present invention, in addition to the above-described functions, the range of the flight trajectory of the golf ball hit and flying, the wind element, the lateral spin (slice / hook) element, the lift element, and the restraint are provided. A flight trajectory variable of the golf ball composed of force elements is calculated, a flight trajectory simulation of the ball is performed using the calculated variable, and the simulation is superimposed on an actual or drawn image of the golf course. It is displayed on a display or the like. Thereby, the trajectory of the actual flight of the ball can be simulated under the conditions including the natural factors, and the golf course play game can be enjoyed while hitting the ball like playing on a real golf course.

According to the third aspect of the present invention, the tee off of the golf ball is detected by the initial velocity vector deciding means of the invention according to the first or second aspect, and further, in relation to the tee off of the golf ball, The three-dimensional position of the flying golf ball within a predetermined time axis is detected, and the speed of the ball is determined from the detected tee position and separation time of the ball and the detected three-dimensional position of the ball within the predetermined time axis. And an initial velocity vector consisting of the shot angle and the exit angle. As a result, an accurate initial velocity vector can be obtained, and the initial ball flight direction can be calculated.

According to the invention described in claim 4, according to claim 1,
In addition to the effects of the invention according to 2 or 3, the golf ball whose variable calculation by the first variable calculation means cannot be performed due to poor illumination at a long distance, poor identification with the background, hindered flight by a protective net, and the like. Is extrapolated based on the variables calculated by the second variable calculation means. Thereby, the trajectory of the unobservable ball can be reproduced on a display or the like.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram of main constituent units according to an embodiment of the present invention. In FIG. 1, an electro-optical device 10 includes a trigger unit 11, an overhead imaging unit 12, and a ground imaging unit 13, which will be described later, and measures an actual flight trajectory of a hit golf ball. The control and display device 14 includes a frame / grabber memory unit 15, a processing and control unit 16, a window memory unit 17, and a display monitor unit 18, which will also be described in detail later. The flight trajectory is reproduced and displayed on the color display monitor. The overhead lighting unit 19 is provided to enhance the electro-optical contrast for measuring the movement of the ball at an early stage of flight. The wind sensor unit 20 is provided to incorporate a wind component into the calculation algorithm of the flight trajectory of the ball. The computer / printer unit 21 is additionally provided as necessary in order to store a score table of players and past data, perform statistical analysis, print, and the like for individuals. The golf course image database unit 22 simulates a complete golf course game played using wood or iron, and is additionally provided as necessary.

FIGS. 2 to 4 show the electro-optical device 1 described above.
The three units 11, 12, and 13 forming 0 are shown and described in detail. The trigger unit 11 shown in FIGS. 2 (a) and 2 (b) is composed of two main and sub units having the same configuration, and two separate rubber tees 11-1 and 11- are respectively provided. It is designed and arranged to fit under 1 '. These are light sources 11-2, 1-1, 1 made of miniaturized photodiodes or laser diodes, respectively.
1-2 ', reflected light detectors 11-3 and 11-3', and light amount change detection circuits 11-4 and 11-4 '.
A first rubber tee 11-1 shown in FIG. 2A is used by being attached to an automatic ball feeder generally used in a modern golf hitting range (practicing range). , In principle. The second rubber tee 11-1 'shown in FIG. 2 (b) is provided for an iron stroke in which the ball is placed directly on the ground (synthetic grass mat). Then, the automatic detection circuit 1 corresponding to the appropriate tee 11-2 (or 11-2 ') in use at that time.
The white reflected light of the ball on the tee is detected and scanned by 1-4 (or 11-4 ') and the detection logic described later. The initial movement of the flight trajectory of the ball is notified by outputting a trigger signal by the fall of the reflected light detection signal when the ball leaves the tee.

The overhead imaging unit 12 shown in FIG. 3 includes two CCD line scanning cameras 3-a or two CCD-scanning cameras.
It is constituted by one of the TV short-time exposure cameras 3-b. Both designs are alternatively chosen, but in each case the camera's field of view is to provide a stable triangulation calculation, and within that field of view the golf club swing, or It is geometrically designed to prevent the ball from the adjacent ball hit lane from entering. In the case of two CCD line scanning cameras 3-a, the camera covers a complete range corresponding to the initial launch angle of the ball, i.e., a single three-dimensional inner plane covering the plane through which the flying ball must pass. It is set up as an image.
In the case of two CCD-TV short exposure cameras 3-b,
The cameras are installed so as to cover a given three-dimensional space with each other. In that space, the ball must be at least a single video frame ("frame" represents one display screen)
Can be observed simultaneously by two cameras within a short exposure corresponding to. As a result, triangulation is performed based on the trigger signal output from the trigger unit 11 and the respective observation angles of the flying ball by the two cameras of the overhead imaging unit 12. This single triangulation is in principle sufficient to determine the initial velocity vector of the flying ball. Furthermore, if this device is used to perform two consecutive triangulation measurements at a certain distance using two sets of CCD line scanning cameras 3-a, the trigger unit 11 Is no longer needed and can be removed. Similarly, for example, if the overhead imaging unit 12 is designed with two CCD-TV cameras and the ball is triangulated at least twice with continuous exposure,
Similarly, the trigger unit 11 can be removed.

FIG. 4 is a diagram for explaining the function of the ground imaging unit 13 shown in FIG. Ground imaging unit 13
Is composed of a CCD-TV high-resolution, variable-exposure camera, and is arranged directly below the tee point and is aligned with the desired direction of the flight trajectory of the ball. Ground imaging unit 1 using this CCD-TV camera
3 is, through the camera window 4-1, the full range of possible initial launch angles of the ball (approximately 7 above the horizontal).
0 degree range) and a sufficient azimuth range of the slice / hook observation angle (approximately ±
20 degrees).

The resolution of the CCD-TV camera must be such that it can indicate the high probability direction of the ball in the largest range of view, ie, to allow the highest possible resolution and the largest possible view. . The highest resolution is
It must be valid over the maximum flight trajectory range (observation angle of low ascent between 10 and 20 degrees from horizontal). The ground imaging unit 13 may be divided and installed in several CCD-TV cameras having different resolutions and partially overlapping visual fields.

The overhead imaging unit 12 and the ground imaging unit 13 shown in FIG. 1 generate a CCD line scanning signal or a reference video signal for a control / display device 14 composed of units 15 to 18. In the case where the overhead imaging unit 12 is two CCD line scan cameras, the frame grabber memory unit 15 can support two analog / digital converters, a multi-line digital RAM, and real-time frame discrimination. It is composed of a multi-image frame grabber (a grabber is a type of digital image RAM that has an input / output video synchronization circuit and operates at high speed). Also,
When the overhead imaging unit 12 is configured by two CCD-TV cameras, a dual-input / multi-image frame / grabber capable of supporting real-time frame discrimination of two simultaneously input images is provided. The processing and control unit 16 is a fast, software-driven, digital signal and image processing unit that performs object detection and its tracking algorithm and calculates the flight trajectory variables of the ball during the tracking process. The wind memory unit 17
It comprises a digital RAM for storing a series of video windows in a selected order for optional immediate playback. The selected video window is a group of data of, for example, 32 × 32 bits (pixels) centered on the ball video signal in each frame.
If the storage capacity of the AM is, for example, 512 × 512 bits, 16 video windows can be stored. The display monitor unit 18 comprises a color display monitor device, as shown in FIG. 4, which is tilted to the player so that the player can easily observe the result of the instant reproduction display, the golf game simulation, or the hitting form. Face-to-face, planted slightly below the ground. The overhead lighting unit 19 of FIG. 1 is, as shown in FIG.
2 is located approximately near. This overhead lighting unit 19
Is intended to further clarify the contrast of the flying ball, which enables the short-time exposure operation of the overhead imaging unit 12. The wind sensor unit 20 of FIG. 1 outputs accurate wind measurements (speed and heading) for all corresponding practice lanes at a driving range. This generates the wind components required to be included in the ball flight trajectory calculation algorithm. The golf course database unit 22 of FIG. 1 comprises a high speed access course image database (eg, a video desk) storing actual or drawn golf course video images and a display processing unit. The flight trajectory of the ball calculated and reconstructed by the system can be superimposed and displayed for simulation.

FIG. 5 shows a flowchart of the overall processing according to the above-described embodiment. This process is started by a trigger signal output by the trigger unit 11. The trigger signal is the firing time of the hit ball and the tee point used at that time (a high tee for a wood or long iron drive shot, or
Ground tee for short iron stroke shots. In step S51, the overhead imaging unit 12 automatically detects and triangulates a flying ball on at least one time axis. Thus, the processing and control unit 16 determines whether or not the generation of a trigger signal, which will be described in detail later with reference to FIG. 6, and the triangulation are performed in a correlated manner. If the occurrences are correlated, in step S52, an initial velocity vector is calculated based on the time data and the tee point position data indicated by the trigger signal and the triangulation result. Subsequently, in step S53, the ground imaging unit 13 is started, and the ball is expected to appear from the calculation result of the initial velocity vector (the initial flight trajectory is considered to be liner-like). Ground imaging unit 1
A small image window (for example, an image range represented by 32 pixels in each of the vertical and horizontal directions) is selected in the image of the CCD-TV camera No. 3 and the image of the ball flying away is captured. Subsequently, in step S54, the flight trajectory tracking process is started based on the initial velocity vector of the flying ball and the image position data of the ball captured by the CCD-TV camera of the ground imaging unit 13. Here, the detection algorithm is applied to video image data continuously input from the ground imaging unit 13. The input video image data for each frame is compared with the initially input video frame, so that a change in the ball position can be detected over the duration of the flight trajectory. This tracking process involves measuring wind components to find flight trajectory range, slice / hook degree, etc., and a Kalman filter, which is the optimal filter for unsteady time series derived, for example, based on the state space method. A model based on a variable calculation algorithm such as that described above is used. This processing is performed in step S5
At 5, the position of the image of the ball in successive video frames is given, and the relevant image window is selected according to the image position, and the selected image window is stored in the window memory unit 17 of FIG. Next, in step S56,
It is determined whether the flight of the ball has ended. The end of this flight trajectory is defined by the fact that the elevation angle of the actual or extrapolated ball described below falls below the horizontal plane. And when the flight of the ball ends,
In step S57, immediate reproduction, simulation, or display of an arbitrary hitting form is started.

In step 51, if there is no trigger signal to signal the start of the triangulation, or if the ball is not detected by the overhead imaging unit 12 even when the trigger signal is present, that is, the correlation between the trigger signal and the triangulation is determined. If not, the process proceeds to step S58. In step S58, it is determined whether there is flight trajectory data previously stored in the memory. If there is data, that is, if there is a previously hit ball, step S5 is immediately performed.
Proceed to step 7. Accordingly, the simulation, the display of the flight trajectory, and the like can be repeated until a new trigger signal is generated and the initial velocity vector is calculated. If there is no flight trajectory data previously stored in the memory in step S58, the first ball stroke has not been performed yet. In this case, the process returns to step S51 to detect a trigger signal. .

The ball supply mechanism in the present embodiment is a modern golf driving range system used today,
For example, automatically send a ball onto a rubber tee,
Then, it may be the same as a ball supply mechanism that lifts the rubber tee on which the ball rides through a hole in the ground (synthetic turf mat) to a predetermined position. Then, the supply of the ball of the automatic ball feeder scans the change of the reflected light from the ball leaving the tee by using an electro-optical mechanism including a light source and a detector installed under the rubber tee. This is done by detecting the flight of the ball. Furthermore, the ball feeder mechanism must have one ball anchoring position that can clearly define when the ball is actually placed on the tee. This allows the reflected light detection circuit of the ball to calculate the reflected light level (average and variation) and to select an appropriate detection threshold.

In the method of the present embodiment, the trigger unit 11 is in principle the same as an existing electro-optical detection mechanism. However, in the case of the present embodiment, the detection circuit has higher sensitivity. In addition, it is set to output a signal exactly in correspondence with the detection time. This enables accurate initial velocity vector calculation.

By the way, there is a possibility that the ball usually leaves the tee in three different states. As a first case, when the ball is hit directly from the tee point, as a second case, when the player removes the ball from a higher tee and replaces it with a lower tee for an iron shot, or The converse or the third case is when the ball happens to fall off the tee. In the first case, as shown in FIG. 2A, the trigger signal is generated at the falling edge of the signal when the detection signal falls below the detection threshold. Therefore, this trigger signal is correlated with the ball detection of the overhead imaging unit 12 and the measurement by triangulation within a reasonable time. The correlation between the trigger signal and the measurement by triangulation together makes it possible to calculate the initial velocity vector. In the second case, the above-mentioned correlation does not occur within a reasonable time since the ball is replaced from one tee on the other. Therefore, the trigger signal from one tee when the ball is first removed is consequently ignored, and subsequently the trigger unit corresponding to the other tee scans the reflected light of the ball. And, for example, when the ball is hit from the lower tee point, the trigger signal is generated from the trigger unit corresponding to the lower tee, and
It correlates with the overhead imaging unit 12 to enable the initial velocity vector calculation. The correlation between the two measurements applies analogously to the decision in the third case above. That is, the generated trigger signal is ignored since it does not correlate with any relevant triangulation measurements.

FIG. 6 is a flowchart for explaining in detail the flow of the trigger detection process of the trigger unit 11 (the determination process of step S51 in FIG. 5). The processing of steps S61 to S63 for a high tee and the processing of steps S61 'to S63' for a low tee are performed simultaneously and in parallel by time sharing. First, processing for a high tee will be described. Step S6 in FIG.
At 1, it is determined whether the ball is placed on a high tee. This means that if there is no ball, no light enters the detector due to reflection, and the output signal is at the "L" level (see FIG. 2 (a)). In this case, the determination processing (reflected light detection processing) of step S61 is repeated. If the reflected light is detected, the ball has been placed on the tee, and in this case, the process proceeds to step S62, and the detection threshold is calculated based on the detection level at this time and the detection level when the ball is not present. And set. This threshold value may be, for example, an intermediate value between the detection levels when the ball is placed on the tee and when the ball is not present. continue,
In step S63, it is determined whether or not a trigger signal has been output from the trigger unit 11. That is, when the detection level of the reflected light becomes equal to or less than the threshold based on the set threshold, the fall is detected and a trigger signal by the trigger unit 11 is output.
The presence or absence of the trigger signal is determined. If there is no trigger signal, steps S62 and S63 are repeated, and if there is a trigger signal, the flow proceeds to step S64. The processing of steps S61 'to S63' for a low tee is exactly the same as steps S61 to S63 described above. In step S64, the notification of the trigger signal detection is transmitted in steps S63 and S6.
3 'is detected, and a measurement based on triangulation is performed based on this information and the position information of the flying ball by the overhead imaging unit 12. Subsequently, in step S64, it is determined whether or not the triangulation measurement is performed within a predetermined time, that is, whether or not the measurement is correlated with the trigger signal. If there is a correlation, an initial velocity vector is calculated in step S66. The process of calculating the initial speed vector in step S66 is exactly the same as the process of calculating the initial speed vector in step S52 of the overall flowchart shown in FIG. If there is no correlation in step S65, the process immediately returns to the determination processing in steps S61 and S61 '.

As described above, when two sets of triangulation measurements can be achieved by the overhead imaging unit 12, the initial velocity vector and the ejection time can be found independently by the overhead imaging unit 12 alone. Sometimes, the trigger unit 11 is not necessary for the operation of the system. Similarly, the overhead imaging unit 12 has one CC
Only the D-TV camera may be used, and the ground imaging unit may be provided with a CCD-TV camera to perform the triangulation measurement for calculating the initial velocity vector.

FIGS. 7 and 8 show the overhead imaging unit 12.
6 is a flowchart for explaining triangulation processing according to the first embodiment. As described above, the overhead imaging unit 12 includes two CCs.
The three-dimensional position of the flying ball is triangulated using either a D-line scanning camera or two CCD-TV cameras.

FIG. 7 shows the processing when two CCD line scanning cameras are used. The processing procedure starts with a trigger signal generated by the trigger unit 11 in step S78. This processing is also performed on one of the two CCD line scanning cameras.
Unit, that is, the processing of steps S71 to S74 by the first unit, and the other one, that is, step S7 by the second unit
The processes 1 'to S74' proceed simultaneously and in parallel. First,
In steps S71 and S71 ', each of the two line scan cameras generates a line scan video signal S (n, t) (n represents a pixel index and t represents a time index). Subsequently, in steps S72 and S72 ', the signal is digitized, stored momentarily in a memory, and subjected to a time difference by the frame grabber unit 15 (D (n, t)). This time difference processing can sufficiently cope with the CCD response and the unsteady observation field of view, and efficiently reflects the reflected light signal of the flying ball in proportion to uncorrelated system noise (noise signal generated in the system). Increase. Next, in steps S73 and S73 ', a detection filter F (n) for which the optimum gain has been determined is obtained. Subsequently, step S7
4. In S74 ', the detection filter F (n) is used for the line scanning signal D (n, t) that is differentiated as described below, and the line scanning signal D (n, t) is observed. Maximize the ball video signal against noise. Variation of line scan data Var
Is calculated and the threshold Thr is the filtered output
Used for I (n, t). S (n, t) = line scan sample of pixel n at time t D (n, t) = S (n, t) −S (n, t−dt); dt = line sampling increment I (n, t) = F (n) CONV D (n, t); CONV represents convolution, F (n) represents a spatial filter with weight “2i + 1” ｛f (-i), ..., f (0 ), ..., f (+ i)｝ Var = E ｛I (n, t) I (n, t)｝-E ｛I (n, t)｝ E ｛I (n
, T)｝; where E ｛｝ is a statistical expectation Thr
= K Var; k is the warning message rate If I (n, t)> Ths, then I (n, t) is a candidate pixel for the ball.

The spatial filter depends on the magnification of the camera. That is, the observed size of the ball depends on the size of the ball, the distance between the ball and the camera, and the focal length of the camera. When the size of the ball is large, the filter is large, and when the size of the ball is small, the filter is small. The weight of the detection filter (spatial filter) is designed so that the response of the filter to the ball image signal is maximized, while the response to system noise is minimized. The optimal filter size for a line scan camera depends on whether the front or rear end of the flying ball is being observed, or whether it is also observing the middle (widest) portion of the ball. Must be changed in real time.

The warning message rate is a rate representing "the degree of error detection per unit time".
A constant to represent this is applied to the threshold for the detection filter output.

As described above, when the pixel signal exceeds the threshold value at a given position in the video image, the detection flag is designated at a specific location. As a result, the observation space and observation time corresponding to the two cameras are sufficiently correlated,
In addition, those that are correlated within a predetermined time after the trigger is transmitted from the tee trigger unit are selected as ball candidate pixel signals.

A pixel signal exceeding the threshold value by the detection filter is a candidate pixel signal of a ball represented in a small video window (video window). Ball candidate pixel signals that do not move along the predicted position calculated by the Kalman calculation process in successive video images are discarded. The predicted ball position is updated every moment as the motion variables are updated.

As described above, when the flying ball is detected by both cameras, the process proceeds to step S75, and the calculation based on triangulation is executed. Subsequently, in step S76,
Both calculation results based on triangulation by two cameras are geometrically compensated for, for example, the difference in the visible range of the two cameras, and the correlation between the two regions is used as a calculation quality criterion. For example, the process proceeds to step S77, where an initial velocity vector is calculated based on the correlation between the injection time indicated by the trigger signal and the tee position used for the stroke and the result of the survey. If the value is equal to or smaller than the predetermined value in step S76, the process waits for generation of the next trigger signal.

With the initial velocity vector calculated in this way, a video window set within the camera field of view of the ground imaging unit 13 is specified, and the trajectory tracking process of the ball is started.

FIG. 8 shows a case where the overhead imaging unit 12 has two Cs.
It is a flowchart of the triangulation process in the case of comprising a CD-TV camera. This process is also started by the trigger signal generated by the trigger unit 11 in step S89. In steps S81 and S81 ', the short-time-exposure CCD-TV camera video signal is digitized synchronously and continuously, and their respective images are simultaneously and immediately obtained in the frame / grabber memory unit 1 in FIG.
5 is stored. In the next steps S82 and S82 ',
The digitized stored signal is timed with respect to an image corresponding to the previously stored signal.
The video frame is composed of two video fields (for example, in the case of a CCD-TV camera that performs standard interlace (interlaced scanning)), each frame is composed of two video fields.
It is divided into one-to-one interlace (composed of two video fields of every other scanning line).

Subsequently, in steps S83 and S83 ', the real-time change amount difference calculation of the image shadow is performed by each CCD.
Calculated for the field of view of the TV camera, based on which the detection threshold is determined and applied to the image. The detection filter (spatial filter) may be applied to the differential image prior to thresholding for optimizing the detection operation and minimizing the warning message rate.

Next, in steps S84 and S84 ', image points (pixels) exceeding the threshold are classified as target pixels (pixels representing a ball), and those target pixels which are closest to each other form a group. Is done. Then the geometric center is calculated. Subsequently, in steps S85 and S85 ', a group that best matches the size of the expected ball image shadow is selected. In step S86, the calculated geometric center of the group is given as the center of two geometric balls from the two cameras, from which a three-dimensional ball position is determined by triangulation calculations. Subsequent steps S87 and S88 are the same processing as S76 and S77 shown in FIG.

The same procedure described above is applied to the second field of view of each camera, from which the three-dimensional position of the ball at the second exposure time is determined. The two three-dimensional ball positions are used to calculate the initial velocity vector and the time of initial firing, since the initial flight trajectory is considered to be liner (not a curve but a straight trajectory). If only one triangulation is performed, then the result must be correlated to the trigger signal and, with reasonable correlation, both results will be in finding the complete initial velocity vector Used. Given the initial velocity vector, the flight trajectory tracking process begins, where a small video window for ball capture is selected within the camera field of view of the ground imaging unit 13 where the flying ball is to be detected.

FIG. 9 is a flowchart of the flight trajectory tracking processing by the ground imaging unit 13. This process is started when an initial velocity vector is given. First, in step S91, a small video window in which a flying ball is expected to appear in a subsequent video frame is selected based on a given initial velocity vector.

As already mentioned, the Kalman filter predicts the upcoming ball position in the updated video image of the ground imaging unit 13. A small video window centered on the image coordinates indicated in the subsequent video image is used for moving ball detection. This is to reduce processing time and computational complexity for subsequent ball detection, to increase the detectability of the correct ball, and to other balls in the driving range. This is done to avoid false detections.

In step S92, the associated video frame is digitized by the frame grabber image memory unit 15. When the flying ball is detected in the selected small video window in the next step S93, the small video window in which the flying ball is detected is stored in the memory of the window memory unit 17 in the following step S94.

If the ground image pickup unit 13 is provided with two or more CCD-TV cameras to increase the resolution, a camera suitable for digital image processing is used depending on the ball position determined in the field of view. Is selected. Similarly,
When performing the ball detection by the overhead imaging unit, the two-dimensional optimal detection filter corresponding to the expansion of the ball video signal is:
It is applied to the digitization of the video frame corresponding to the small video window calculated to capture the ball.

This initial video frame remains in the image memory for complete flight trajectory processing and is used as the associated image to differentiate all subsequent video images.

That is, in step S95, the subsequent difference image is filtered by an appropriately sized and optimized detection filter and thresholded to extract ball candidate pixels. The size of the optimal detection filter is
As the distance of the ball increases, it decreases in the following video frame. Further, as an indication of the enhancement of the flight trajectory, there is a decrease in the ball video signal with respect to the noise ratio. This decreases throughout the flight of the ball to a point where it can no longer be detected. The azimuth and elevation of the ball observed by the camera of the ground imaging unit 13 are determined by the wind memory unit 17.
Is used to select the small video window stored in the
Used for ball tracking and flight trajectory variable calculation algorithms (eg, Kalman filter). The size of the video window is updated according to the degree of detection certainty and the measurement reliability of the tracking process. The observation angle calculated for the ball in each video frame from the ground imaging camera is calculated in step S9.
In detail, the wind speed is calculated by taking into account the wind speed data to be described later or extrapolated and updated by taking into account the wind speed data described later. Then, in step S96, while the angle of elevation of the observed ball is larger than a given threshold value, for example, horizontal (elevation angle of 0 degree), the process returns to step S92 and returns to step S9.
Steps 2 to S96 are repeated. If the observation elevation angle falls below 0 degree in step S96, the flight trajectory tracking process ends.

The flight trajectory variable calculation processing based on the above model depends on the dynamic equation of motion of the flight trajectory of the ball. The main forces that determine the ball's flight trajectory at each point during flight are (a) gravity force, (b) drag force, (c) bottom spin lift, (d) transverse spin slice or The hooking force, and (e) the wind element. The flight trajectory is in a plane that contains the normal to the surface of the ground when forces (a)-(c) are applied with a headwind or tailwind (see FIG. 12). Similarly, when there is a lateral spin or a crosswind, the flight trajectory becomes a three-dimensional gentle space curve. The motion equation of the ball can be represented by two sets of one-dimensional nonlinear difference equations over time.
Given the initial velocity vector of the ball, the results of the initial deterrent and uplift coefficients, and the wind velocity vector, the forward speed and angle can be calculated progressively with a small time increment, thereby allowing the flight to proceed. It is possible to calculate the entire flight trajectory without tracking the ball inside (CBDaish, "
The Physics of Ball Game ", English Univ. Press, 197
2). This equation of motion is given below.

Dθ / dt = −v2 / a−g sin (θ) dθ / dt = k−g cos (θ) / v where, v: velocity with respect to air, g: gravitational acceleration, θ: flight angle (horizontal And t: time, a: suppression coefficient, k: lift coefficient.

These equations are completed by substituting the induction time by the increasing difference approximation formula. The initial velocity vector measured by the overhead imaging unit 12 and the trigger unit 11 gives initial values of “v” and “θ” including the wind velocity. The wind speed vector is obtained by dividing the wind speed vector into two components, namely, 1 along the instantaneous ball speed direction.
The decomposition into one component and its second component in the normal direction results in a vectorwise addition to the ball velocity vector under each incremental calculation. The flight angle “θ” is calculated using the observation angle from the camera of the ground imaging unit 13 (see FIGS. 10 and 11). The wind component along the instantaneous ball velocity vector mainly affects the lift and deterrence applied to the flying ball, and the normal component rotates the plane of motion. For the track distance over which the flying ball passes, in other words, the incrementally completed track distance, velocity relative to the ground should be used, not velocity relative to the air. Lift and deterrent variables ("a" and "k", respectively)
") Is a non-linear function of velocity which is not clearly defined, from which it becomes necessary to track and iteratively calculate those variables. Observation angles from the ground imaging unit 13 in successive video frames are included in the calculation process and, along with preliminary approximations of deterrence and elevation,
Enables more accurate discovery of flight trajectory range and slice / hook factors. FIG. 10 shows a flowchart of the immediate reproduction display processing. This process is started when the end of the trajectory is verified. The detected and calculated ball image position is displayed in the small image window stored in the memory unit 17,
Corresponding to this, it is used for reproduction in an image frame stored in the display monitor unit 18.

FIG. 11 shows a flowchart of the golf course game simulation processing. This process also
It starts when the end of the orbit is verified. The ball position, calculated three-dimensionally over the trajectory, is displayed and superimposed graphically and realistically on the relevant golf course image from unit 22.

[0050]

According to the present invention, the flight trajectory of a golf ball in a three-dimensional space is analyzed and calculated by electro-optical measurement, and an image of the flight trajectory of the golf ball can be immediately reproduced and displayed. Includes slices and hooks, even if the ball is not clear enough to make it difficult to see, if the ball is difficult to identify due to the intricate background, or if the protective net is not large enough to prevent the ball from flying midway Since the flight trajectory of the golf ball can be observed as an image up to its end point, even if the lighting at night is insufficient, the background is complicated and the ball is difficult to identify, or if the practice field is narrow, it is important to Regardless of the result of the hitting, it is possible to observe the hitting result to the end and practice with a high correction effect. In addition, since the simulation can be performed by superimposing on the actual or drawn golf course image, it is possible to know the hitting result by proceeding as if the ball was actually shot at the golf course, and It becomes possible to enjoy the game alone or by several people. Further, since the image of the ball in flight is stored using the minimum digital video memory, the effect of using the storage device is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of main constituent units according to an embodiment of the present invention.

FIGS. 2A and 2B are diagrams illustrating a trigger unit.

FIG. 3 is a diagram illustrating an overhead imaging unit.

FIG. 4 is a diagram illustrating functions of a ground imaging unit.

FIG. 5 is a flowchart of an overall process according to the embodiment.

FIG. 6 is a flowchart illustrating a trigger detection process in detail.

FIG. 7 is a flowchart illustrating triangulation processing when the overhead imaging unit is configured by two CCD line scanning cameras.

FIG. 8 is a flowchart of a triangulation process in a case where the overhead imaging unit includes two CCD-TV cameras.

FIG. 9 is a flowchart illustrating a flight trajectory tracking process performed by the ground imaging unit.

FIG. 10 is a flowchart illustrating an immediate reproduction display process.

FIG. 11 is a flowchart illustrating a golf course game simulation process.

FIG. 12 is a diagram illustrating a method of calculating a trajectory of a golf ball. Reference Signs List 10 electro-optical device 11 trigger unit 12 overhead imaging unit 13 ground imaging unit 14 control / display device 15 frame grabber memory unit 16 processing and control unit 17 window memory unit 18 display monitor unit 19 overhead illumination unit 20 wind sensor unit 21 Computer / printer unit 22 Golf course database unit 11-1, 11-1 'Rubber tee 11-2, 11-2' Light source 11-3, 11-3 'Reflected light detector 11-4, 11-4' Light intensity change detection circuit 111-5 Synthetic grass 3-a Two CCD line scanning cameras 3-b Two CCD-TV short-time exposure cameras 4-1 Camera window

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) A63B 69/36 522 A63B 69/36 541 A63B 67/02

Claims (4)

(57) [Claims] 1. Golf that is hit and hit from above the tee
Observation means to observe the ball electro-optically by triangulation
From the observation result observed by the observation means,
Variable of the initial velocity vector of the golf ball flying by
A first variable calculating means for calculating the first variable, and the first variable calculated by the first variable calculating means .
Before flying in an observable state determined based on the observation direction
The flight of the golf ball is repeatedly performed by the observation means.
Obtained by observation by electro-optical tracking and triangulation
The flight trajectory of the golf ball is changed in the second
A second variable calculating means for calculating as a number, poor illumination at a long distance, poor identification with the background, and flying by a protective net.
Observation by the second observation means becomes impossible due to line obstruction, etc.
Is calculated in advance by the second variable calculating means.
The golf ball hit by the second variable
Calculate the estimated flight trajectory after the above-mentioned unobservable point
Estimated trajectory calculating means, and a flight of the golf ball calculated by the second variable.
Flight trajectory or flight calculated by the estimated trajectory calculation means
Storing the orbit on a memory;
Instantly reproduces the image of the trajectory of the
Video playback means, and a range of flight trajectory of the hit golf ball.
Enclosure, wind element, slice or hook horizontal spin element, lift
Flight of golf ball consisting of force element and deterrent element
A third variable calculating means for calculating a third variable of the trajectory, and a third variable calculated before the second variable and the third variable calculating means.
The golf ball hit using the second and third variables.
The flight trajectory of the
The image of the flight trajectory of the golf ball
Is the image weight superimposed on the golf course image by drawing
Ball hitting training and simulation method , comprising: tatami mat means . 2. The tee is electro-optically disposed within the tee,
Detecting the separation of the golf ball from the tee,
A detachment signal output unit that outputs a detection signal, wherein the observation unit is disposed near the tee;
In front of the golf ball detected by the de-signal output means
Withdrawing from the tee in correlation with the departure from the tee
Third order of the flying golf ball within a predetermined time axis
The original position is detected, and the first variable calculation means is detected by the departure signal output means.
Tee position and separation time of the released golf ball
And the golf ball observed by the observation means
From the three-dimensional position within the predetermined time axis
Initial velocity vector consisting of flying ball speed and launch angle
The golf hitting training and simulation method according to claim 1, wherein the torque is calculated . 3. The observation means is arranged in the vicinity of the tee.
Equipped with two cameras for triangulation, and the two cameras
Two consecutive flights flying away from the tee
Of golf ball detection and triangulation in a typical place
And the first variable calculation means detects the detection by the observation means.
Tertiary of the golf ball obtained by and triangulation
The first variable is determined as the initial velocity vector according to the original position.
2. The golf hitting training and simulation method according to claim 1, wherein: 4. The observation means comprises two cameras,
First measure the first variable by two consecutive triangulations
And then repeat the detection and tracking of the golf ball
Performed continuously while calculating the second variable by angular survey
The golf hitting training and simulation method according to claim 1, wherein: