GOLF ANALYSIS SYSTEM WITH FRAMELESS OPTICAL SENSOR NET

Abstract

A golf analysis system includes a light emitter assembly, including first and second light emitters spaced apart from one another, and a light detector assembly, including first and second sets of light detectors arranged along a surface of a practice area beneath the light emitters. The light emitters emit first and second spreads of non-parallel light rays, received by the light detectors, to form an optical sensor net for capturing relational kinetic information when at least one of a golf ball and a golf club passing through the optical sensor net. The region between the level of the light detectors and the level of the light emitters is substantially free of mechanical structure.

Description

BACKGROUND OF THE INVENTION

The present invention relates to golf analysis and analysis devices. More specifically, the invention is directed to golf analysis systems with optical sensor nets that capture and process dynamic spatial information for a golf ball and/or a golf club.

There are a variety of apparatus and methods in the golf industry that provide limited information relating to golf ball trajectory and speed. Because a golf ball in flight generally adheres to the same basic principles of physics as other projectile objects, available systems today attempt to provide calculated information such as estimated carry and flight path based on numerous ball measurements obtained by a host of detectors and other related equipment.

Many systems have been proposed in the past to measure spatial positioning and information for a golf ball, a tennis ball or any other spherical projectile. These systems generally include numerous detectors and switches located along an expected flight path for the object. The spherical object may thus impinge upon particular detectors to thereby actuate corresponding electrical switches. Many transmission type or reflection type photoelectric switches may be also placed along an expected flight path, and may be actuated when a ray input for particular switches are blocked off by the object. Scanning laser beams have been also proposed that are paralleled across an expected flight path of a spherical object by using a concave mirror and lens system. The spherical object may pass through a scanning plane to thereby measure beam cut-off timing to determine launch positioning and angles for the spherical object in flight. At the same time, visual systems have also been provided that provide video camera images of the projectiles to provide relevant spatial information.

There are many disadvantages to these present day analysis and analysis systems which have been adapted for golf ball and club swing analysis. For example, some systems affect the intended path of the projectile or fail to obtain careful measurements which provide inaccurate flight information. Most apparatus also require a large number of switches, sensors or detectors to cover a relatively wide flight path area for the spherical projectile. In order to overcome some of the foregoing disadvantages or problems of the conventional measuring methods, systems have been proposed for determining the position of a flying spherical object with a parallel light band generated and projected onto a screen to form a linear image region. When a spherical object in flight crosses the parallel light band, it creates a silhouette on the screen within the image region. The position of this silhouette is detected by using sensors to thereby determine an instantaneous spatial position of the flying spherical object. The disadvantages for this system have been further overcome with measuring apparatus that purportedly determines instantaneous positioning of the object in flight without coming into contact therewith. The flight information may include speed, position and launch angle. Despite the foregoing efforts, golf training systems today still require excessive instrumentation and equipment.

The system disclosed in U.S. Pat. No. 6,302,802 addresses many of the above-described issues. However, it requires a standout post which can visually and physically hinder or interfere with the player and also the ball flight. In addition, it does not have left/right symmetry to allow both left and right handed players to play under the same physical setting. Examples of the invention described below will effectively answer such concerns and limitations by requiring no standout post and allow both left and right handed players to play under the same physical setting.

BRIEF SUMMARY OF THE INVENTION

Examples of methods and apparatus for golf analysis systems with optical sensor nets are described. Dynamic spatial information may be provided based upon either or both a golf ball and club information. A compact, effectively single plane optical sensor net is thus capable of capturing this information relating to a golf ball and/or a golf swing. Plural optical sensor nets may also be used with some examples. Relevant ball information may be measured and derived with the systems described herein that includes ball speed, ball take-off and azimuth angles, which may in turn provide relevant calculated ball information such as ball spin, carry distance, trajectory, flight time and height. Golf club information may be also measured and derived to provide club swing path, head speed (before and after impact) head twist and club face angle throughout the swing.

Various examples of golf analysis systems provide ball flight and club swing information with an optical sensor net formed with intersecting rays of light. Ball speed and club speed information maybe detected with either parallel or non-parallel rays of light. Club path information may be provided based on either parallel or non-parallel rays of light. It shall be understood that particular features of the described embodiments and examples in the following specification may be considered individually or in combination with other variations and aspects of the invention.

A first example of a golf analysis system includes a light emitter assembly and a light detector assembly. The light emitter assembly includes first and second light emitters spaced apart from one another by first distance while the light detector assembly includes first and second sets of light detectors arranged at a first level along a surface of a practice area. The practice area includes a tee region and an intended golf ball path extending from a chosen tee location within the tee region. The first and second sets of light detectors are positioned opposite one another and are oriented transversely to the intended golf ball path. The first and second light emitters are capable of emitting first and second spreads of non-parallel light rays to be received by the first and second sets of light detectors, respectively. The first and second light emitters are located at a second level vertically above the practice area by at least a second distance. The first and second spreads of non-parallel light rays form an optical sensor net to permit capturing relational kinetic information of at least one of a golf ball and a golf club during a golf club swinging motion on the practice area when at least one of the golf ball and golf club passes through at least a portion of the optical sensor net. The region above the first level and below the second level is substantially free of mechanical structure to prevent inadvertent contact between a golf ball or a golf club and such mechanical structure during the golf club swinging motion.

In some examples of the golf analysis system, the first and second light emitters emit laser light downwardly toward the first and second sets of light detectors at angles of about 5° to 15° from vertical. In some examples, the second distance is at least about 9 feet. In some examples, first and second light emitter assemblies and first and second light detector assemblies are used to define first and second optical sensor nets; the first and second optical sensor nets can be oriented generally parallel to one another. In some examples, the light emitters are capable of providing information to a data processor.

An example of a method for enabling the determination of dynamic spatial information for a golf practice swing using a golf analysis system including an optical sensor net, is carried out as follows. A golf practice swing is taken at the tee region of a practice area of the golf analysis system with or without hitting a golf ball along an intended golf ball path. At least one of a golf club head and a golf ball hit by the golf club is passed along a golf ball/club path through an optical sensor net. The optical sensor net emits first and second spreads of non-parallel light rays downwardly from first and second light emitters of a light emitter assembly, the first and second light emitters spaced apart from one another by a first distance and located vertically above the practice area by at least a second distance. The optical sensor net also receives the first and second spreads of non-parallel light rays by first and second sets of light detectors of a light detector assembly, respectively. The first and second sets of light detectors are arranged along a surface of the practice area, with each set of light detectors comprising a plurality of detector elements. At least two of the non-parallel light rays are interrupted by at least one of the golf club head and the golf ball. Substantially all mechanical structures above and nearby the practice area between the level of the practice area and the level of the first and second light emitters are eliminated to prevent inadvertent contact between the golf ball or the golf club and such mechanical structures during the practice swing.

In some examples, the method also includes identifying light detector elements that receive interrupted non-parallel light rays as a result of the practice golf swing, measuring interruption times for the identified detector elements that detect the interrupted non-parallel light rays, and determining dynamic spatial information for the golf club practice swing based on the measured interruption times for the selected light detectors that receive interrupted non-parallel rays of light; the identifying, measuring and determining steps carried out using information supplied by at least the light detector assembly providing data to a data processor. In some examples, the method is carried out with the tee location being undetermined.

Other features and advantages of the invention will become apparent upon further consideration of the specification and drawings. While the following description may contain many specific details describing particular embodiments and examples of the invention, this should not be construed as limitations to the scope of the invention, but rather as an exemplification of preferable embodiments. For each aspect of the invention, many variations are possible as suggested herein that are known to those of ordinary skill in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a somewhat simplified, overall view of a golf analysis system using an optical sensor net.

FIG. 2 is a diagram illustrating the calculation of ball speed based on the disruption of a sensor net with non-parallel rays of light.

FIG. 3 is a simplified drawing demonstrating the calculation of relative golf ball and club speed in accordance with another aspect of the invention.

FIGS. 4 and B are diagrammatic explanations that describe yet another aspect of the invention that provides directional information for a golf ball path.

FIG. 5 is a diagrammatic explanation for determining the path of a spherical projectile such as a golf ball based upon the disruption of selected optical beams.

FIG. 6 is a simplified side view of another golf analysis system that provides both golf club and ball dynamic spatial information.

FIG. 7 is a simplified schematic diagram illustrating the apparatus and steps involved with processing and receiving information from the optical sensor nets described herein.

FIG. 8 is an example of visual output that may be provided by the apparatus described herein that includes relative golf club and ball information.

FIGS. 9A-B are simplified illustrations describing the off-centered contact and effect on a golf ball in relation to the club head.

FIGS. 10A-B are enlarged visual output illustrations that provide captured golf club information after contact with a golf ball.

FIG. 11 illustrates an example of a golf analysis system similar to that of FIG. 1 but in which the light emitter assembly is positioned above the light detector assembly.

FIG. 12 is a front view of the golf analysis system of FIG. 11.

FIG. 13 is a simplified side view of the golf analysis system of FIG. 11.

FIG. 14 is an exaggerated view similar to FIG. 13 showing how the first and second sets of light detectors of the light detector assembly are spaced apart from one another so that the light rays from the first and second light emitters of a light emitter assembly are at slightly different angles to the vertical.

FIG. 15 is a view similar to that of FIG. 13 of another example of a golf analysis system using two light emitter assemblies and two light detector assemblies to create two optical sensor nets spaced apart from and generally parallel to one another.

DETAILED DESCRIPTION OF THE INVENTION

The following description will typically be with reference to specific structural embodiments and methods. It is to be understood that there is no intention to limit the invention to the specifically disclosed embodiments and methods but that the invention may be practiced using other features, elements, methods and embodiments. Preferred embodiments are described to illustrate the present invention, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a variety of equivalent variations on the description that follows. Like elements in various embodiments and examples are commonly referred to with like reference numerals.

This invention is based on the method and apparatus disclosed in U.S. Pat. No. 6,302,802. FIGS. 1-10B and the associated description of those figures are taken from that patent.

FIG. 1 illustrates a golf analysis and training system 10 with an optical sensor net 20 provided in accordance with the invention. An important advantage provided by the example of FIG. 1, as well as with the example of FIG. 11, is that the ball may be placed at various locations with respect to optical sensor nets within the analysis systems described herein. The ball is not necessarily positioned at a fixed spot as with most earlier apparatus. An individual may thus strike golf balls freely without multiple sensors and fixed tee positions which may be selected nonetheless in order to provide even more ball and club information.

As shown in FIG. 1, the analysis system 10 may include a substantially L-shaped frame having a first leg 12 and a second leg 14 or extension. The first leg 12 may be positioned in a relatively horizontal position, and the second leg 14 may be placed in a substantially vertical tilted position. Either or both legs may be formed with a bent configuration to form a curved shape. The system may further include a light emitter assembly with a first light emitter 16 connected to the first leg 12 of the frame, and a second light emitter 18 connected to the second leg 14 of the frame. Each light emitter 16 and 18 may emit a spread or fan of non-parallel light rays in a substantially single plane. The first and second light emitters 16 and 18 may also emit pulsed laser beams, and may be filtered to differentiate the rays of light produced by ambient illumination from those produced by the golf ball crossing the optical sensor net 20.

In other examples, the light emitter assembly may include at least one optical beam splitter to split a single beam of light from the light emitter equally to its respective light detectors. The light emitter assembly may thus provide a focused laser beam and a beam splitter that generates diverging rays of light that are received by light detectors within the system. A variety of anti-reflective coatings may be selected as is known in the art to promote permeation of light rays through the beam splitter and other components of the light emitter assembly.

The optical sensor nets provided herein are capable of measuring and processing relational dynamic information for both a golf ball and a golf club. An array of light detectors with a first set of spaced apart light detectors may be positioned along the first leg of the frame to receive the non-parallel light rays emitted from the second light emitter. A second set of spaced apart light detectors may be positioned along the second leg of the frame that receive the non-parallel light rays emitted from the first light emitter. The array of light detectors on the first leg and the second leg of the frame may be spatially aligned and arranged at a predetermined space interval that is less than the radius of the golf ball. As a result, the non-parallel rays from both the first and the second light emitter provide an asymmetrical optical sensor net that captures relational kinetic information for a spheroidal object such as a golf ball and a golf club during a swinging motion when passed through at least a portion of the sensor net. Moreover, the asymmetrical optical sensor net may provide a two-dimensional and single planar optical net having relatively uniform density. The size of the sensor net may be varied according to desired operating parameters, and may preferably have dimensions ranging from 2 to 4 feet. Various combinations of additional light emitters and detectors may be selected.

A data processor 22 may be also provided with the optical sensor net that is in communication with the light emitter assembly, the array of detectors or any combination of selected components within the golf analysis system. The data processor or computer 22 may be connected to timers and related instrumentation to measure periods of disruption for selected light detectors by the golf ball and by the golf club. Moreover, the data processor may process relational kinetic information for the golf ball and the golf club based on the disruption of selected light detectors and their respective time periods of disruption. A visual display 24 may be further provided to display data generated from the movement of the golf ball and/or golf club.

As shown in FIG. 1, the golf analysis device may include an optical grid or net 20 positioned at an angle. A generally L-shaped frame for the system may be positioned with respect to the ground at a preselected or variable angle (θ). A relatively horizontal leg portion 12 of the frame may rest on the ground in proximity to the ball hitting area, and a relatively vertical leg portion 14 of the frame angle may extend upwardly in a general direction towards the player. The frame angle θ may range from about 10 degrees to 90 degrees, and preferably between about 30 to 60 degrees. The vertical leg portion 14 may also include a stand or support to assist in maintaining the frame in a relatively fixed position. The open-construction of an L-shaped frame described herein enables a player to swing through the optical sensor net with minimal risk of striking portions of the analysis system. Other frame configurations may be selected having additional leg sections that permit free passage of a golf ball and/or club through the optical sensor nets 20 described herein. The angled configuration of the system 10 also captures relatively more golf club information during the swing, particularly when positioned relatively close to the individual player thus providing a compact golf analysis system. The tilted frame positioned at preferable angles tends to capture higher angles of changing golf shots with different trajectories. Moreover, the angled positioning of the frame and sensor net may provide improved resolution of golf club swing information. Dynamic spatial information for a golf ball may be similarly captured and processed simultaneously. After the golf ball passes through the optical sensor net 20, it may be retrieved or caught in a ball net, not shown, positioned along the flight path of the ball to allow an individual to hit multiple balls in order to gather more golf ball and club information.

Another variation provides an optical sensor system for measuring dynamic spatial information of a substantially spheroidal projectile. The sensor system may include a support frame having at least two extensions with at least one light source or laser that emits non-parallel rays of light. Each light source may be positioned at a location along the frame in a predetermined plane or pattern. A plurality of light detectors may be aligned and arranged at predetermined spatial intervals along the support frame. The light detectors may be also positioned and spaced apart for detecting the non-parallel rays of light emitted from a light source. A first light source may emit a first set of non-parallel rays of light to a first set of light detectors, and a second light emitter may emit a second set of non-parallel rays of light to a second set of light detectors. The light source may be a semiconductor diode laser with a cylindrical lens positioned along an optical axis that provides divergent rays of light to form a substantially fan-shaped pattern or configuration. For example, the light source may be arranged to emit a laser beam of 3-20 mW in consumptive power and 630-790 nm in wave length. A variety of other light sources with different power and frequency output may be selected to form an array of non-parallel rays of light. Selected lenses, filters and beam splitters may be also selected to provide dispersion of the light rays from a single light source. Additionally, a variety of light detectors or photosensors may be selected in accordance with the invention including PIN, MSN and diodes which are available from vendors like Hewlett-Packard, Temic, Siemens and Hamamatsu.

The first and the second set of light detectors within the analysis system may detect intersecting non-parallel rays of light to provide an asymmetrical two-dimensional or single planar optical sensor net. The sensor net may be formed at a variety of angles with respect to the ground, preferably angled more towards an individual player to capture more swing information and to provide a compact system. The various interruptions of the rays of light within the sensor net may be thus detected and measured when the spheroidal projectile, club shaft, and club head pass through the rays of light. A data processor and instrumentation may be also selected for communication with the plurality of light detectors to measure a plurality of interruption times in which the rays of light to selected light detectors are interrupted or blocked off by the spheroidal projectile. Moreover, the data processor or microprocessor may process and provide dynamic spatial information for the spheroidal projectile based on the location and the interruption time for each selected light detector. Given the diameter length of the spheroidal object, each light detector may be spaced apart a defined distance that is less than the radial length of the spheroidal object so that at least two rays of light are interrupted. A variety of predetermined information for the projectile or golf ball may be further stored in a memory coupled to the microprocessor. The combination of stored information and measured readings from the optical sensor net within the analysis system provide dynamic spatial information for the spheroidal projectile such as its speed and direction. This information may be in fact derived without a predetermined initial position or velocity for the projectile. A distinct advantage provided in accordance with the invention is the calculation of dynamic ball information without necessarily fixing the distance between a golf ball and the sensor net. Additional sensors and switches may be included in the analysis system nonetheless to determine an initial launch event or location, but is not required. Moreover, the dynamic spatial information may include certain correction factors that account for variable playing conditions such as wind speed and direction, humidity, temperature, pressure. These environmental conditions may reflect existing hitting conditions or various simulations that may be stored in the system memory, and executed upon command as desired by the individual.

As shown in FIG. 2, the calculation of ball speed and direction may be based on the measured disruption of light rays within an optical sensor net formed with non-parallel rays of light. Three or more rays of light may be disrupted within the sensor net. A plurality of individual detectors (n, n+1, n+2 . . . ) may detect their respective rays of light which may be spaced apart a predefined distance. For example, when multiple laser beams are cross-sectionally sectionally blocked off by a flying golf ball 30, the measured blocking time (t_n, t_n+1, t_n+2 . . . t_n+i) may correspond or translate into the physical length of cross-sectional portions of the ball (d_n, d_n+1, d_n+2 . . . d_n+i). t_n may be defined as the time interval that blocks off a ray of light for the n^th detector, and the time base may be measured and provided by the instrumentation within the analysis system. d_n may be defined as the length of the distance for the ball that blocks off light being directed to the n^th detector. Because the golf ball diameter and curvature may be predetermined as a known variable, and the beam interruption times may be measured, the entire image of the ball may reconstructed along with its discrete cross-sectional paths. Once the image of the golf ball is fitted or matched against the cross-sectional paths, the location of the center of mass may be obtained. Accordingly, the ball speed, direction and trajectory may be based upon measurable ball path information that is derived from the laser beam blocking paths.

In accordance with this aspect of the invention, an optical sensor system may thus provide instantaneous dynamic information for a spherical projectile such as a golf ball. The sensor system may include a structural support frame with at least one light emitter assembly that emits non-parallel rays of light to form an optical sensor net. The support frame can be formed with two extensions that generally provide an L-shaped design. A first light emitter assembly may be positioned on the first extension, and a second light emitter assembly may be positioned on the second extension. The light emitter assemblies may each include a light source and an optical element or lens that provides non-parallel rays of light. The light emitter may be a focused laser light source, or non-coherent LED or white light, and the optical element may be a beam splitter or cylindrical lens. Each laser light source may provide a focused laser beam through an optical beam splitter to split rays of light equally to a plurality of selected light detectors. The light detectors may be spatially arranged to form an asymmetrical optical sensor net for detecting the multiple rays of light emitted from the light emitter. Furthermore, the light detectors may be positioned along the support frame and spaced apart at selected or predetermined spatial intervals for detecting the non-parallel rays of light emitted from the first and the second light emitter assemblies. These spatial intervals may be varied, and may be equal to or less than a predetermined radius for a golf ball. As a result, the flying spherical object blocks off at least three rays of light to provide dynamic spatial information in accordance with the invention. The light detectors may be further arranged relatively vertically or horizontally in-line with the light emitter assembly to detect emitted light and the interruption times for respective rays of light when the spherical projectile passes through the optical sensor net. In addition, the sensor system may include instrumentation and a data processor in communication with the light detectors for measuring and processing a plurality of interruption times in which the rays of light to selected light detectors are interrupted or blocked off by the spherical object. The blockage time of the rays of light may be measured and inputted into a computer with arithmetic operators that detect a single or a plurality of photodiodes for which the rays of light are blocked off. A system microprocessor may be also selected for processing and calculating substantially instantaneous dynamic information for the spherical projectile based on available information including the location and the interruption time for each selected light detector. Additionally, a visual display may be selected to display data generated from the movement of the golf ball.

Another aspect of the invention provides dynamic spatial information for both a golf ball and a club. As shown in FIG. 3, the variation of the invention may include optical sensor nets similarly described herein with either non-parallel or parallel rays of light. As with other embodiments of the invention described herein, ball and club speed may be calculated without tee sensors or hitting the ball from a fixed location. An optical sensor net 32 may be positioned in the line of the intended ball path 34 to capture information relating to the ball 30 and the golf club 40 based upon the disruption times for selected rays of light. An L-shaped frame may be selected for these analysis systems to allow an individual to hit the ball 30 and swing through the sensor net 32. When the golf ball 30 passes through the optical net 32, the initial time may be established t=0. The time for detecting the ensuing golf club by the optical net 32 following the golf ball 30 may be defined as t=t_c. At this time, it may be assumed the ball 30 was hit at t=x which is unknown at this point. The club speed after impact may be expressed as:

$V_{\mathrm{ca}}=\frac{d_c}{t_c-X}$

Ball speed may be defined as:

$V_b=\frac{d_b}{-X}$

g may be also determined by experimental data, and may represent the potential energy of the shaft during impact of the club to the ball. Accordingly, when the principle of the conservation of energy is applied then:

$\frac{1}{2}M_cV_{\mathrm{cb}}^2=\frac{1}{2}M_bV_b^2+\frac{1}{2}M_cV_{\mathrm{ca}}^2+g\left(\frac{1}{2}M_cV_{\mathrm{ca}}^2\right)$

wherein M_c is the mass of the club, V_cb is the velocity of the club before impact, M_b is the mass of the ball, V_b is the velocity of the ball after impact, and V_ca is the velocity of the club after impact. f may represent the speed ratio which is related to the club and ball momentum transfer due to impact, and may be a function of the ball speed that is determined by experimental data.

$V_{\mathrm{cb}}=\sqrt{V_{\mathrm{ca}}^2+a\frac{V_{\mathrm{cb}}^2}{f^2}+gV_{\mathrm{ca}}^2}$

wherein a is the mass ratio between the club and the ball, a equals approximately M_b/M_c

$V_{\mathrm{cb}}^2=V_{\mathrm{ca}}^2\left(1+g\right)+\frac{a}{f^2}V_{\mathrm{cb}}^2$ $V_{\mathrm{cb}}=\sqrt{\frac{1+g}{1-\frac{a}{f^2}}V_{\mathrm{ca}}}$ $A=\sqrt{\frac{1+g}{1-\frac{a}{f^2}}V_{\mathrm{ca}}}$ $X\left(t_c\right)=fd_b\frac{t_c}{fd_b-d_c}$

wherein t_c is the measured time data between the ball and the club passing through the optical sensor net, d_c=d/cos θc, and d_b=d/cos θb. As a result, the following may be obtained:

$V_b\left(t_c\right)=\frac{d_b}{-X\left(t_c\right)}$ $V_{\mathrm{cb}}\left(t_c\right)=V_b\left(t_c\right)·f$ $V_{\mathrm{ca}}\left(t_c\right)=\frac{V_{\mathrm{cb}}\left(t_c\right)}{A}$

Based upon experimentation and field analysis, f has been determined by the following expression:

f(V_b)=(0.07+0.04 V_b)

wherein V_b may be measured in mph or miles per hour, and g has been determined to be between 0.01 and 0.1 depending upon the shaft selected. Accordingly, with the above calculations, the ball speed (V_b) and the club speed (V_ca) may be calculated without having a sensor positioned at a tee position. It has been observed that the accuracy in determining speed is better than 0.1% if a spacing of about 10 inches is used between the net and the tee positions. In the tilted frame configuration, this calculation may be readily determined since d_b and d_c may be readily determined from the frame position regardless if it is relatively perpendicular to the ground at 90 degrees or tilted.

A method can provide dynamic spatial information based upon the relations described above for moving objects with an optical sensor net. The method may include the initial selection of a sensor system with a divergent light source for emitting at least two non-parallel rays of light towards an array of light detectors to form an optical sensor net. At least one moving object such as ball and/or golf club may pass through the non-parallel rays of light within the optical sensor net to interrupt emission of the rays of light to the array of light detectors. Selected light detectors may be identified that receive interrupted rays of light emitted by the divergent light source caused by the moving object passing through the optical sensor net. The interruption times for the selected detectors within the array of light detectors may be measured, and the dynamic spatial information may be thus provided for the moving object based on the measured interruption time for the selected light detectors that receive interrupted non-parallel rays of light. The moving object may be a golf ball with a preselected diameter, a golf club or both.

Another variation for this aspect of the invention may include parallel or non-parallel laser beams to improve the accuracy of determining the ball and club positions by applying the concept of a weighting correction. When the frame is titled, at different ball takeoff and azimuth angles, the number of beams that will be blocked off by the ball and the club will be different. It is thus possible to use the total number of beams blocked off by the ball at different angles to improve the accuracy of determining the ball and club positions as shown in FIGS. 4A-B. Depending on the relative angle of the optical sensor net, and flight path of the ball and the swing path of the golf club, the number of optical beams that are blocked will be different. In one instance, as shown in FIG. 4A, only beams #2, 3 and 4 are blocked by a passing ball. Meanwhile, in FIG. 4B, beams #2, 3, 4 and 5 are blocked when the ball and/or optical net are positioned at relatively different angles. The number of beams blocked, for how long, and in which sequence, all provide information in accordance with this aspect of the invention to provide ball information such as speed and direction.

With respect to yet another aspect of the invention, as shown in FIG. 5, the ball speed and its relative direction may be detected with parallel or non-parallel beam of light without knowing the initial starting or tee position of the ball. An outer frontal surface of the golf ball intercepts an optical beam plane upon contact. The golf ball intercepts optical beam #1, 2, 3, 4 and 5 at t=t₁, t₂, t₃, t₄, and t₅, respectively. By examining the time ratio of t₁, t₂, t₃, t₄ and t₅ (since the curvature of the golf ball may be considered a given parameter), the ball speed and direction may be determined without knowing its original position by:

Step 1: determining how many beams are blocked

Step 2: determining which beam is blocked first

Step 3: determining the time ratio between each beam in reference to the first beam

Step 4: since there is only one direction of the traveling ball that will match the time ratio given by the data, the direction of the ball may be determined with appropriate time resolution between the blocking times for each beam t₁ . . . t₅

Step 5: once the direction or the relative angle with reference to the optical beam plane is known, the ball speed may be also determined based on the interruption time by the ball with a known curvature.

This first example thus provides methods and apparatus for calculating ball traveling information without fixing the ball starting position or the time of impact when the club hits the ball. The time ratios between different blocked beams are measured to provide ball flight information. By applying the curvature of the ball, and by knowing the time when each beam is blocked, the ball location may be better estimated by using a simple averaging method.

$\mathrm{Ball}\mathrm{Center}\mathrm{Position}=\frac{\sum _{i=1}^N\left(i^{\mathrm{th}}\mathrm{beam}\mathrm{position}\right)\times \left(\Delta t_i\right)}{\sum _{i=1}\Delta t_i}$

N may be defined as the number of beams blocked by the ball.

Another aspect of the invention provides dynamic spatial information for a golf club as it passes through optical sensor nets described herein. With respect to this variation of the analysis systems described herein, as illustrated in FIG. 6, portions of the club shaft 46 and the club head 48 are detected and monitored by the sensor net 42 as the club passes through. In addition to detecting ball flight path 44 and information as described herein, the analysis system may determine both the club swing path 52 and any twisting of the club head due to torque applied by hitting the golf ball off-center with respect to the center of gravity for the club head. Although a tilted L-shaped frame is shown in FIG. 6, it shall be understood that frames with other configurations may be selected that are not tilted. Similarly, the optical sensor net 42 may include both parallel and non-parallel rays of light with respect to this aspect of the invention. The swing path 52 and club head movement may be detected and tracked with the optical sensor net 42, and relevant time data may be collected or measured so that important golf swinging information may be observed and communicated to a player. When a player is preferably positioned relatively close to the net 42 so that club information may be determined, both ball and golf club information may be derived by identifying which light detectors are disrupted, and for how long. The initial disruption of the net 42 is typically caused by the golf ball 50 passing through, which may be followed by the club head 48. A method may be thus provided in accordance with the invention for obtaining dynamic spatial information which includes the step of passing a golf club through either parallel or non-parallel rays of light within the optical sensor net to interrupt emission of the rays of light to the array of light detectors. A group of selected light detectors may be identified that receive interrupted rays of light emitted by the divergent light source caused by the golf club passing through the optical sensor net. The interruption times for the rays of light to this group of selected detectors may be detected and measured within the system. As a result, dynamic spatial information may be computed for the golf club based on the measured interruption time for the selected light detectors that receive interrupted non-parallel rays of light. This includes club speed and swing path information. Similarly, another group of selected light detectors may detect and measure interruption times for a golf ball to provide relevant ball information such as speed and trajectory as it also passes through the net when the swing analysis system is configured to not only detect the golf club swing.

FIG. 7 is a simplified schematic diagram illustrating the apparatus and steps involved with processing and receiving information from the optical sensor nets described herein. A microprocessor control system may be provided that comprises a set of detectors and lasers mounted on a mechanical frame to form an optical detection net. The system may further include an analog to digital (A/D) converters or conditioning circuitry, a computer or central processing unit (CPU) that receives or takes the detector input to perform selected or necessary logic determination, a read-only memory (ROM) bank that may contain the algorithms for performing CPU computations, a random access memory (RAM) bank that stores computational data, a logic decoder, and sets of output ports such as serial bus or universal serial bus (USB) that communicates with displays and/or other personal computers.

When a golf player swings a club to make impact to a golf ball, the ball passes through the optical net first to trigger the electronic circuitry within the computerized analysis system to commence the collection of data relating to both the golf ball and the club. After the circuitry is initially triggered by the relatively fast moving golf ball, the microprocessor and RAM may begin to collect the data over a predetermined period of time until the following club passes through the optical net to acquire all needed data for computation. The ball and club swing path signals received from the laser light detectors may be first sorted by the analog to digital (A/D) circuitry for proper coordinate and time-duration information. The collected information may be subsequently analyzed by the microprocessor or CPU using the predetermined algorithm that may be stored in memory or the ROM bank. After microprocessor computation is performed, the computed data may be temporarily kept in the RAM for additional computation if needed or desired. The determined ball speed, ball take-off directions, ball traveling trajectory, club swing path, club face angle, and club head twisting information may be then directed through the decoder to communicate with different peripherals including displays and other computer systems for additional processing such as other golf analysis, training and gaming applications including home entertainment systems and video games. After the ball and club swing information is passed to the display or additional PCs, the electronic system may be reset to receive new data. An LED indicator on the optical frame may be lighted to indicate the readiness (READY) of the unit for next play or golf shot.

With the electronic detection circuitry and apparatus described herein, a printed visual output may be provided as shown in FIG. 8 that includes relative golf club and ball information. The output may include an image representing the path of the ball and a separate image representing the golf club. A horizontal axis of the output may be divided to illustrate images of the ball and club along both the X-axis and the Y-axis. The output may be derived from the disruption of rays of light within the net, and may be translated into images corresponding to selected detectors that are disrupted. At the same time, a vertical axis of the output may be a time scale starting from time=0 when a first group of disruption times for selected detectors in the net is observed which is typically caused by the ball, and a second group of disruption times for selected detectors in the net caused by the club. A variety of time scales may be also selected for these systems including a 10⁻⁶ second scale as shown to capture data from the optical sensor net. The general path of the ball may be tracked with the image provided in relation to a complementary image of the club shaft. The flex of the club shaft may be even observed with the displayed output. As with other embodiments of the invention described herein, a compact sensor net with a tilted design may provide more relevant golf club information since a relatively larger portion of the club shaft and head information may be captured by the closely positioned sensor net. The combined information and output may be thus used to calculate the ball flight and club swing to provide realistic or near realistic ball trajectory predictions.

A variety of algorithms may be developed for the golf analysis systems described herein to provide pattern recognition of club swing information that indicate club head twist direction after impact with a golf ball. For example, as shown in FIGS. 9A-B, an off-centered contact with the ball as with toe shots cause the club head to generally rotate in a clockwise rotation as illustrated. A toe shot generally occurs when contact with the ball is not made with its center of mass (CM), and away from the player. The club head and shaft image is captured by the optical sensor nets provided herein as a function of time as illustrated in FIGS. 10A-B. The club image for a toe shot may be captured along an X-axis and plotted against time as shown in FIG. 10A. Similarly, when a head shot occurs wherein the contact with the ball is not made with the center of mass for the club and is towards the player, the club head may generally rotate in a relatively counter-clockwise rotation. As illustrated in FIG. 10B, the club image for a head shot may be captured to reflect this type of contact with the golf ball. Based upon the club swing information provided with the optical sensor nets systems herein, corrective steps may be prescribed during training so desirable square contact between the golf ball and golf club can be achieved.

Examples of Frameless Golf Analysis Systems and Methods

The following will describe examples of golf analysis systems 10 in which the light emitter assembly 11 is positioned above the light detector assembly 13, sometimes referred to as frameless golf analysis systems 10. A first example of frameless golf analysis system 10 is shown in FIGS. 11-13. First and second light emitters 16, 18 are mounted to the ceiling 56 or other frameless structure spaced apart from one another by a first distance 58. First distance 58 is typically about 2-4 feet. The vertical distance 59 between ceiling 56 and a support surface 60 is typically about 9-12 feet. A practice area 62, typically in the form of a practice area mat 62, is positioned beneath light emitter assembly 11 and is used to support a tee 64 at a chosen tee location 66 within a tee region 68. In some examples, chosen tee location 66 is fixed while in other examples, it may be changed. Practice area mat 62 can be made of, for example, a firm elastomeric material having a thickness of about 1-3 inches

Light detector assembly 13 includes first and second sets 70, 72 of light detectors 74. Although first and second sets 70, 72 of light detectors 74 can be mounted on top of practice area mat 62, they are preferably embedded within practice area mat 62. The distance 75 between the ends of light detector assembly 13 is typically corresponds to first distance 58, typically in a range of 2-4 feet. However, in some cases it may be desired to make the distances 58, 74 substantially different from one another, such as if the shape or size of optical sensor net 20 is to be changed. Light detectors 74 in each set 70, 72 are preferably spaced apart from one another by a distance no greater than about the minimum radius of a typical golf ball, typically about 0.8 inch. First light emitter 16 directs a first spread of first light rays 26 at the light detectors 74 of first set 70 of light detectors. Second light emitters 18 direct a second spread of second light rays 28 at the light detectors 74 of second set 72 of light detectors. The region where first and second light rays 26, 28 overlap one another is referred to as the optical sensor net 20.

With golf analysis system 10 shown in FIG. 1, all of the light detectors are arranged in a common plane. The calculations for this configuration of FIG. 1 are discussed above with regard to FIGS. 1-10B. However, with the frameless golf analysis system 10 of FIGS. 11-13, if detectors 74 for both of the first and second sets 70, 72 of light detectors were aligned, then detectors 74 would not be able to differentiate between first light rays 26 from first light emitter 16 and second light rays 28 from second light emitters 18 without making the system more complicated by, for example, having first and second light rays 26, 28 at different frequencies coupled with the ability to distinguish between the different frequencies of light received by detectors 74. Therefore, it is presently preferred that the first and second sets 70, 72 of light detectors be separated a short distance from one another while being oriented parallel to one another. The separation is shown in an exaggerated manner in FIG. 14.

To put X₁ and X₂ (two interrupted spatial coordinates by a flying golf ball 30 or a swinging club shaft 40 or a swinging club head 48) onto the same space plane, a special coordinate algorithm that matches the shape of the optical sensor net geometry is used to find the distance d between X₁ and X₂. Because the space coordinates of the frameless golf analysis system 10 of FIGS. 11-14 has 2-fold symmetry along the target line, meaning the coordinates space out in actual space are left-right mirror imaged in reference to the target line, the space coordinates can be uniformly distributed within the detection area. This is in contrast to the situation where the space coordinates are asymmetrical and not uniformly distributed. Thus it is possible to use the frameless golf analysis system 10 of FIGS. 11-14 to calculate the ball take-off and azimuth angles by determining the actual and predicted intercept time differences between adjacent intercepted beam. This algorithm may be explained as follow.

As described earlier, the ball center position can be generally determined by

$\mathrm{Ball}\mathrm{Center}\mathrm{Position}=\frac{\sum _{i=1}^N\left(i^{\mathrm{th}}\mathrm{beam}\mathrm{position}\right)\times \left(\Delta t_i\right)}{\sum _{i=1}\Delta t_i}$

N may be defined as the number of beams blocked by the ball. The ball speed can be determined by measuring the longest intercept time for the golf ball to travel through laser beams.

Ball speed (Vb)=[(golf ball radius)*(ball curvature and center position adjusted distance factor)/(longest laser beam intercept time)]

Once the ball center location is known and ball speed determined, based on the curvature of the ball the starting point of each intercepted coordinate (i.e., beams blocked) can then be predicted if the ball is traveling along the perpendicular direction toward the laser beams. If in reality the ball is now traveling in directions other than the perpendicular one then the actual measured intercept time, relative to each adjacent laser beam, will be different from the predicted time. Thus if one can determine the initial block-the-beam time and its difference to the predicted time in Y direction (left-right), then it represents the effect due to azimuth angle, and in Z direction (up-down) then it represents the effect due to take-off angle. Thus after the first beam is blocked, the time of the adjacent beam to be blocked can be predicted if the ball is traveling in the perpendicular direction to the beam and measured based on the actual travel direction, then the angles may be calculated based on the following equation:

Delta angle=arctan {[(predicted time)−(actual time)−(ball curvature correction factor)]/predicted time}

The actual azimuth and take-off angles will be further corrected by the tilting angle θ of the laser beams which is defined in FIG. 11. This is new features based on the frameless golf analysis system 10 of FIGS. 11-14 where the laser beams are 2-fold symmetry and uniformly distributed within the detection area, comparing to the prior art arrangement where the laser beams are asymmetry and non-uniformly distributed.

This special coordinate algorithm will then assign X₁′=X₁+d/2 and X₂′=X₂−d/2, which will shift X₁′+X₂′ onto the same space plane for ball-information calculations. In the example of FIGS. 11-13, first and second sets 70, 72 of light detectors are very close to one another so that the tilt angle θ is slightly different for each. Tilt angle θ is preferably about 5 degrees to 15 degrees. In the example of FIGS. 11-13, θ₁₁ is equal to about 9.46 degrees and θ₁₂ is equal to about 9.59 degrees. The rest of the calculations remain identical to those discussed above with regard to FIGS. 1-10B.

FIG. 15 is a view similar to that of FIG. 13 of another example of a golf analysis system 10 using two light emitter assemblies 11A and 11B along with two light detector assemblies 13A and 13B. Doing so creates two optical sensor nets 20A and 20B spaced apart from and generally parallel to one another. First optical sensor net 20A is oriented as a first tilt angle θ₁ while second optical sensor net 20B is oriented at a second tilt angle θ₂. The first and second tilt angles may be the same or different. The distance 76 between first and second light detector assemblies 13A and 13B is typically equal to about 25% to 100% of distance 75 between the ends of light detector assembly 13. One advantage of system 10 of FIG. 14 is that chosen tee location 66 can be changed by the user without requiring any input into the system. This is because the two separate sensor nets can provide the needed spatial information (since two points can define a straight line of objective motion in space) required to calculate both ball and clubhead motions in space without the prerequisite of defining the tee location with good accuracy. Two-sensor nets can also provide a parallel check on each other (when used as an individual sensor net) to ensure there will be no miscalculation occur during the ball and clubhead motion detection and calculation. A disadvantage associated with the use of two-sensor net is the extra cost involved.

A primary advantage of using frameless golf analysis systems 10 as shown in FIGS. 11-15 is the elimination of the presence of the legs 12, 14 of the frame in the example of FIG. 1. Even if legs 12, 14 do not interfere with a user's golf swing, the presence of the frame legs can sometimes be viewed negatively by the user. Another advantage over the example of FIG. 1 results from frameless system 10 having left-right symmetry so it will allow both left handed as well as right-handed players to play on the same system setup without any changes or modifications.

The above descriptions may have used terms such as above, below, top, bottom, over, under, et cetera. These terms may be used in the description and claims to aid understanding of the invention and not used in a limiting sense.

While the present invention is disclosed by reference to the preferred embodiments and examples detailed above, it is to be understood that these examples are intended in an illustrative rather than in a limiting sense. It is contemplated that modifications and combinations will occur to those skilled in the art, which modifications and combinations will be within the spirit of the invention and the scope of the following claims. For example, although each set 70, 72 of light detectors 74 arrange the light detectors in straight lines, in some situations it may be desired to have light detectors 74 are arranged in other than straight lines. Although it is presently preferred to use a single light emitter 16, 18 for each set 70, 72 of light detectors, if desired more than one light emitter may be used for each set of light detectors, even to the point of using a separate light emitter for each light detector 74 (too extreme to be implemented). In each of the examples, light emitter assembly 11 is located vertically above a position between tee 64 and light detector assembly 13; in some examples, light emitter assembly 11 may be positioned directly vertically above light detector assembly 13 or in front of the light detector assembly; however having optical sensor net 20 tilt forwardly to a more vertical position would reduce the amount of swing information and increase the size of the overall system structure in order to capture the same amount of the information.

Any and all patents, patent applications and printed publications referred to above are incorporated by reference.

Claims

1. A golf analysis system comprising: a light emitter assembly comprising first and second light emitters spaced apart from one another by first distance;a light detector assembly comprising first and second sets of light detectors arranged at a first level along a surface of a practice area, the practice area comprising a tee region and an intended golf ball path extending from a chosen tee location within the tee region;the first and second sets of light detectors positioned opposite one another and oriented transversely to the intended golf ball path;the first and second light emitters capable of emitting first and second spreads of non-parallel light rays to be received by the first and second sets of light detectors, respectively;the first and second light emitters located at a second level vertically above the practice area by at least a second distance;the first and second spreads of non-parallel light rays forming an optical sensor net to permit capturing relational kinetic information of at least one of a golf ball and a golf club during a golf club swinging motion on the practice area when said at least one of the golf ball and golf club passes through at least a portion of the optical sensor net; andthe region above the first level and below the second level being substantially free of mechanical structure to prevent inadvertent contact between a golf ball or a golf club and such mechanical structure during the golf club swinging motion.

2. The golf analysis system according to claim 1, wherein the first and second light emitters emit laser light.

3. The golf analysis system according to claim 1, wherein each of the first and second spread of non-parallel light rays extend downwardly toward the first and second sets of light detectors at angles of about 5° to 15° from vertical.

4. The golf analysis system according to claim 1, wherein the first and second light emitters are located at positions vertically above locations situated between the first and second sets of light detectors and the tee region.

5. The golf analysis system according to claim 1, wherein each of the first and second sets of light detectors comprise individual light detectors separated by distances that are less than the minimum radius of a typical golf ball of about 0.8 inch.

6. The golf analysis system according to claim 1, wherein the first and second sets of light detectors define a cross sectional ball/clubhead detection area with a first width and a first height of the optical sensor net.

7. The golf analysis system according to claim 6, wherein said detection area is about 2 to 4 feet in both width and height.

8. The golf analysis system according to claim 1, wherein the first and second sets of light detectors are oriented generally perpendicular to and generally centered on a plane extending vertically or tilted vertically at about 5 to 10 degrees downwardly from the intended golf ball path.

9. The golf analysis system according to claim 1, wherein the second distance is at least about 9 feet.

10. The golf analysis system according to claim 1, comprising first and second light emitter assemblies and first and second light detector assemblies defining first and second optical sensor nets, said first and second optical sensor nets being spaced apart from one another.

11. The golf analysis system according to claim 10, wherein the first and second optical sensor nets are oriented generally parallel to one another.

12. The golf analysis system according to claim 10, wherein the first and second light detector assemblies are oriented generally perpendicular to and generally centered on the intended golf ball path.

13. The golf analysis system according to claim 10, wherein: the first and second sets of light detectors of the first light detector assembly define a cross sectional area with a first width and a first height;the first and second light detector assemblies being separated by a distance of about 100% of the first width.

14. The golf analysis system according to claim 1, wherein the light emitters and detectors are capable of providing information to a data processor.

15. The golf analysis system according to claim 1, further comprising visual display to display data generated by the data processor from the movement of the golf ball through the optical sensor net.

16. The golf analysis system according to claim 1, further comprising a catching net placed along the golf ball intended path.

17. A method for enabling the determination of dynamic spatial information for a golf practice swing using a golf analysis system comprising an optical sensor net, the method comprising: taking a golf practice swing at the tee region of a practice area of the golf analysis system with or without hitting a golf ball along an intended golf ball path;passing at least one of a golf club head and a golf ball hit by the golf club along a golf ball/club path through an optical sensor net;emitting, by the optical sensor net, first and second spreads of non-parallel light rays downwardly from first and second light emitters of a light emitter assembly, the first and second light emitters spaced apart from one another by a first distance and located vertically above the practice area by at least a second distance;receiving, by the optical sensor net, the first and second spreads of non-parallel light rays by first and second sets of light detectors of a light detector assembly, respectively, the first and second sets of light detectors arranged along a surface of the practice area, each set of light detectors comprising a plurality of detector elements;interrupting at least two of said non-parallel light rays by said at least one of the golf club head and the golf ball; andeliminating substantially all mechanical structures above and nearby the practice area between the level of the practice area and the level of the first and second light emitters thereby preventing inadvertent contact between the golf ball or the golf club and such mechanical structures during the practice swing.

18. The method according to claim 17, further comprising: identifying light detector elements that receive interrupted non-parallel light rays as a result of the practice golf swing;measuring interruption times for the identified detector elements that detect the interrupted non-parallel light rays; anddetermining dynamic spatial information for the golf club practice swing based on the measured interruption times for the selected light detectors that receive interrupted non-parallel rays of light; andthe identifying, measuring and determining steps carried out using information supplied by at least the light detector assembly providing data to a data processor.

19. The method according to claim 18, further comprising: placing a golf ball at a tee location within the tee region;determining the location of the tee location relative to the optical sensor net; andproviding tee location information to the data processor.

20. The method according to claim 18, further comprising: placing a golf ball at a tee location within the tee region;wherein the passing step comprises passing the golf ball through first and second optical sensor nets, the optical sensor nets spaced apart from one another at first and second positions along the intended golf ball path, the use of the first and second spaced apart optical sensor nets eliminating a need to provide the tee location information to the data processor.

21. Given an undetermined tee location, a method for providing dynamic spatial information with an optical sensor net for a golf practice swing comprising the steps of: selecting a sensor system including a divergent light source for emitting at least two non-parallel rays of light towards an array of light detectors to form an optical sensor net;passing the golf ball through the non-parallel rays of light within the optical sensor net to interrupt emission of the rays of light to the array of light detectors;identifying selected light detectors that receive interrupted rays of light emitted by the divergent light source caused by the golf ball passing through the optical sensor net;detecting interruption times for the selected detectors within the array of light detectors that detect interrupted rays of light;measuring dynamic spatial information for the golf ball based on the detected interruption times for the selected light detectors that receive interrupted non-parallel rays of light;identifying second, third, and fourth groups of selected light detectors that receive interrupted rays of light emitted by the divergent light source caused by the golf ball passing through the optical sensor net;detecting interruption times for the second, third, and fourth groups of selected detectors within the array of light detectors that detect interrupted rays of light; andcomputing dynamic spatial information for the golf ball based on the measured interruption times for the selected light detectors that receive interrupted non-parallel rays of light.

22. The method for providing dynamic spatial information as recited in claim 21, further comprising: passing a golf club through the optical sensor net through the non-parallel rays of light within the optical sensor net to interrupt emission of the rays of light to the array of light detectors;identifying a second group of selected light detectors that receive interrupted rays of light emitted by the divergent light source caused by the golf club passing through the optical sensor net;detecting interruption times for the second group of selected detectors within the array of light detectors that detects interrupted rays of light; andcomputing dynamic spatial information for the golf club based on the measured interruption time for the selected light detectors that receive interrupted non-parallel rays of light.

23. The method for providing dynamic spatial information as recited in claim 21, wherein the dynamic spatial information includes golf ball speed and trajectory.

24. The method for providing dynamic spatial information as recited in claim 21, wherein the dynamic spatial information includes club speed information and club swing path information.

25. Given an undetermined tee location, a method for providing dynamic spatial information with an optical sensor net for a golf practice swing comprising the steps of: selecting a sensor system including first and second divergent light sources for emitting at least two non-parallel rays of light from each divergent light source towards first and second arrays of light detectors to form first and second optical sensor nets;passing the golf ball through the non-parallel rays of light within the optical sensor net to interrupt emission of the rays of light to the first and second arrays of light detectors;identifying selected light detectors that receive interrupted rays of light emitted by the divergent light source caused by the golf ball passing through the optical sensor nets;detecting interruption times for the selected detectors within the first and second arrays of light detectors that detect interrupted rays of light;measuring dynamic spatial information for the golf ball based on the detected interruption times for the selected light detectors that receive interrupted non-parallel rays of light;identifying second, third, and fourth groups of selected light detectors for each of the first and second arrays of light detectors that receive interrupted rays of light emitted by the divergent light source caused by the golf ball passing through the optical sensor net;detecting interruption times for the second, third, and fourth groups of selected detectors within the first and second arrays of light detectors that detect interrupted rays of light; andcomputing dynamic spatial information for the golf ball based on the measured interruption times for the selected light detectors that receive interrupted non-parallel rays of light.

26. The method for providing dynamic spatial information as recited in claim 25, wherein the dynamic spatial information includes golf ball speed and trajectory.

27. The method for providing dynamic spatial information as recited in claim 25, wherein the dynamic spatial information includes club speed information and swing path information.