EP2201987B1 - Device and method for recognising the movement of a golf club - Google Patents

Abstract

The detection and analysis device comprises one or multiple signal sources arranged on a golf stick. One or multiple illumination devices (1.3,1.4) are accommodated in a stationary device (1) with one or multiple detectors (1.1). The illumination devices emit one or multiple focused light beams (1.3.1,1.4.1) to produce a light spot on a surface, which serve as a marker for the arrangement of the feet of the golf player. An independent claim is also included for a method for detecting and analyzing the striking motion of a golf stick for knocking a golf ball.

Description

The invention relates to an apparatus and a method for detecting and analyzing the movement of a golf club serving to knock off a golf ball.

At least since the seventies of the last century, attempts have been made to support the learning of the optimum knock-down motion by means of EDP-assisted recording, analysis and presentation of the swinging movement of a golf club by a golfer.

According to the US 3792863 A Mechanical measurements (acceleration, torsion, elongation, bending) are measured on the head and stem of a golf club, the results are transmitted by radio to an evaluation unit and processed by it clearly. The more achievable learning effect is more indirect. The measuring and transmission units are exposed to high mechanical stresses and therefore expensive to keep and calibrated only at great expense.

According to the DE 19732151 A1 Also mechanical sizes are measured on the racket. Upon reaching a certain value, photos are automatically taken on the basis of which the player can control his attitude at that time. The same concerns apply as with the US 3792863 A ,

In the US 5,067,717 A It is proposed to attach light sources to the golfer's head, arm and thighs and to analyze light sensors in the environment for movement. From a certain degree of deviation from an ideal range of motion an error message should sound. If at all feasible the equipment is very complex and the learning effect is only very indirect.

It is generally customary to film learners when a golf ball is knocked off and then to analyze the movement on the basis of the video running in slow motion with the assistance of a specialist. The method is technically easy to implement and it is very enlightening in the initial stage. However, it hardly provides "objective", quantified statements such as Speeds in certain phases of movement and it is hardly usefully applicable without the permanent support of a professionally trained person.

The DE 100 54 282 A1 and the DE 102 46 808 A1 describe methods and apparatus for determining the position and orientation of an object - such as a golf club - in space. From a plurality of points of the object, a light pulse is emitted in a time window assigned to the respective point. The light pulse is perceived by at least two detectors spaced apart from one another. The individual detectors not only detect the fact of the light striking, but also the angular position of the incoming light in space. From the measurement results of two spaced-apart detectors for a transmitted light pulse, the position of the emitting point is calculated by triangulation. By measuring the positions of a plurality of light-emitting points which are attached to an object at a distance from one another, the position of the object itself in space is detected. According to this approach, relatively inexpensive, robust and accurate measuring devices can be provided. Nothing is said about the difficulties in the practical application of the method with regard to the fact that comparable results should be recorded for several measurements.

The object underlying the invention is to provide a composite of a device and a method for operating this device method to detect the movement of a golf club for knocking a golf ball to analyze them. Irrespective of where it is used, the method should provide comparable results to each other, and should be useful for laypersons alone, if necessary after initial training.

To solve the problem, a method is assumed in which the golf club is emitted by at least two mutually spaced points of light pulses which can be assigned to these individual points and which are perceived by two fixed, spaced apart detectors of an evaluation , is automatically calculated from the angles of incidence at the individual detectors on the position of the emitting points and thus the position and position of the golf club and from a rapid time sequence of many such measurements and related calculations, the course of movement of the golf club as a result of individual, too taken at defined times, position measurements are recorded. According to the invention, it is provided in a device which includes the two mutually spaced detectors to accommodate one or more lighting devices which emit one or more focused light rays, which each cause a light spot on a surface at which they impinge and thus the place for mark the arrangement of the golfer's feet and / or the location of the golf ball being dropped.

Fig. 1:

ist eine perspektivische Skizze eines ortsfesten Gerä- tes, welches Teil einer Vorrichtung gemäß der Erfindung ist.

Fig. 2:

ist eine perspektivische Skizze eines Golfschlägers mit einem darauf angebrachten und damit mitbewegten Sendeteil welcher Teil einer Vorrichtung gemäß der Erfindung ist.

Details and advantageous developments are explained with reference to an embodiment sketched in two drawings.

Fig. 1:

is a perspective sketch of a stationary device, which is part of a device according to the invention.

Fig. 2:

is a perspective sketch of a golf club with an attached and thus mitbewegten transmitting part which is part of a device according to the invention.

The golf club 3 according to Fig. 2 consists of a handle 3.1, a handle 3.2 and a club head 3.3. On the stem 3.2 of the golf club, the movable part, which is here referred to as "transmitting part 2" is releasably attached.

The transmitting part 2 has an elongated support part 2.1, which is attached to the handle 3.2 of the golf club and extends several decimeters along this. At its two ends of the elongate support member 2.1 is provided with a respective signal generator 2.2.

The signal transmitters 2.2 are components which send a short light pulse, preferably in an infrared radiation spectrum, to the environment at regular time intervals. Typically, they are realized by means of light-emitting diodes and a drive circuit for them.

It is essential for the function that the transmitted light pulses from a receiver can each be assigned exactly to the individual signal transmitter 2.2 from which they were emitted. This can be realized for example quite simply and energy-saving with a so-called time slot method. In this case, a period of a common, time-repeating sequence is divided into individual "time slots", ie phase areas. Each of the signal transmitters can only send a signal in a specific time slot assigned to it. For a synchronized to the periodic sequence receiver of the light pulses thus recognizable by the reception time of a light pulse, from which signal generator this light pulse must come.

In addition to the time slot method, there are, of course, a wealth of other ways of encoding the light pulses for assignment to an individual signal generator.

The two signal transmitters 2.2 are attached to a common elongated support member 2.1 and their distance from each other is determined by their arrangement on the support part 2.1. Compared to an arrangement as mutually independent units which are to be fastened separately on the golf club 3, thus adjusting effort is avoided when attaching the signal generator on the golf club. So that measurements with different golf clubs are comparable to one another, either the transmitting part 2 is to be arranged at a predefined defined distance from the club head or the club grip, or one of these distances is to be measured and input to the evaluating device 1.

In a preferred embodiment, the individual signal transmitters 2.2 have around the cross-sectional area of the stem 3.2 a whole series of individual emission points for the light signals to be transmitted. There are basically two options for operating these individual points using the time slot method.

In a first operating mode, all emission points of a signal generator can simultaneously emit a light signal. The individual emission points of a signal generator are then not distinguishable by a detector; from the common light signal is assumed as the position of the signal transmitter about the center of gravity of all emission points of the signal generator, which light up to the detector. The angle of rotation of the racket 3 about its longitudinal axis is not visible in this method. But it is ensured that movements of the racket in all other degrees of freedom can be very well recognized because Irrespective of the angle of rotation, an operating signal generator is always perceived and only two series of measurements must be recorded, with which one can work with a high temporal resolution of individual measurements per measurement series.

In a second operating mode, the individual emission points of a signal generator 2.2 are each assigned their own time slots. This means for the measurement that not only two series of measurements for the position of two signal transmitters are recorded, but that the number of signal generators times the number of their emission points is to be included in measurement series. With this method, the angular position of the racket with respect to rotation about its longitudinal axis can be determined. A disadvantage is the larger data accumulation and that it is not possible to measure so frequently according to the individual emission points, since not only two measurements have to be carried out within an overall period of measurements, but also said higher number, whereby the minimum period duration must necessarily be set longer.

In order to be able to adapt the method to the respective situation, it should be possible to switch over between the two operating modes. Of course, both modes of operation "individual emission points of a signal generator not distinguishable" and "individual emission points of a signal generator distinguishable" can also be realized with other coding methods than the time slot method.

Fig. 1 "Steady" in this context does not mean "immobile" (like a building), but only that the device 1 does not move as intended during the execution of a golf shot relative to the tee of the golf ball may be.

In the stationary device 1, two light detectors 1.1 are arranged at a distance of several decimeters from each other, which are adapted to detect the light emitted by the signal transmitters 2.2 of the transmitting part 2 so that they upon striking a light signal, an electrical signal or a combination of give off electrical signals, from which it is not only recognizable that light has arrived at a certain time, but also from which angular position in the room it arrived. It makes sense to set the detectors sensitively, for example by means of an optical filter layer, exclusively to those spectral ranges in which the signal transmitters 2.2 emit light.

By measuring the light signal emitted by a signal transmitter at two spaced-apart light detectors 1.1, the position of the relevant signal transmitter relative to the two light detectors 1.1 can be recalculated by triangulation. This recalculation takes place automatically, either in a computer unit in the device 1 itself or in a computer connected to it. The series of temporally successive measurement results is at least temporarily stored in the device 1. Since two series of detectors 2.2 measure a series of positions, two such series of measurements are stored. Good and easily machinable and processable results can be achieved if the said period is for example 4 milliseconds and the duration of a single light signal is for example 10 microseconds.

The function of position determination described in the previous two paragraphs is, for example, by the writings mentioned above DE 100 54 282 A1 and the DE 102 46 808 A1 known prior art, which is why not further discussed here. New are the additional functions, which by the device 1 offered, through which the method is only comfortable use.

A lighting device 1.3, which can typically be realized by a semiconductor laser, sends out a light pointer 1.3.1 to that point on the ground, to which the golfer should stand, so that the measurement can be carried out in an optimal manner. If - as outlined - the cross-sectional shape of the luminous pointer 1.3.1 indicates the outline of the sole surface of shoes, so it can be displayed not only the place where the golfer in relation to the device 1, but also the arrangement and orientation of the Feet of the player on the ground and thus also its orientation. The lighting device 1.3 thus not only characterizes the location at which the golfer should stand, but also its orientation. For example, instead of displaying the outline of the sole surfaces, an arrow may be projected onto the ground, the point of impact of the luminous pointer symbolizing the location, and the arrow direction symbolizing either the front of the golfer or the target tee for the golf ball.

Preferably, the lighting device 1.3 is supplemented by a laser distance measuring device, by means of which the distance of the is measured, which has the light spot, which is caused by the light beam 1.3.1 on the ground to the device 1. Thus, the position of the golfer relative to the device regardless of the height of the stand 4 and unevenness or inclination of the terrain is detected. Based on this knowledge, the recorded motion curves can be easily converted by coordinate transformation to a normalized representation, which also recorded in different places and at different times Movement curves are directly comparable to each other.

A second lighting device 1.4 sends a light pointer 1.4.1 to that point at which the golf ball to be played is to be laid. Here, too, it makes sense to combine the light pointer with a laser distance measuring device, so that not only the directional position of the golf ball relative to the device 1 is defined or detected, but also the distance. Preferably, the light pointer shows 1.4.1 and the target tee direction of the golf ball, for example, in that its cross-sectional shape has the shape of an arrow.

A camera 1.2 for recording a film or a series of rapid succession recorded individual photos is also housed in the device 1. She picks up the golfer at the tee movement. By being able to precisely define the position of the player and the ball in front of the tee relative to the device due to the light pointer 1.3.1 and 1.4.1, the camera 1.2 can also be automatically adjusted to the optimum correct direction and distance. If you work with rigid specifications regarding the height of the tripod 4 and the angles of the luminescent hands 1.3.1, so it can be made with the same terrain conditions very well comparable to each other film or photo shoots of many tee operations, as thus always from the same direction and Distance filmed or photographed.

In order to be able to ensure the optimum function of the system or of the method, the device 1 itself must also be held in a defined position. For this purpose, preferably equipped with a device for measuring its inclination, for example with a spirit level. Furthermore, it is the tripod 4 via a bracket fastened, which between a first state in which the device 1 relative to the stand about mutually non-parallel horizontal axes is pivotable and a second state in which the device 1 is completely fixed against movement relative to the tripod, can be switched.

At its top, the device 1 is provided with a flat, at least approximately horizontally oriented surface 1.5. This is sufficiently large to be able to turn off a portable computer on it. The device 1 is provided with an interface for bidirectional data transmission with a computer, so that measurement results and recorded films or images can be transmitted to a computer. Further analysis, meaningful representation and storage of this data is then carried out with the help of the computer.

Of course, it is also possible in a construction variant to equip the device 1 itself with a display device and software for the evaluation and display of measurement data, as well as with a large data memory and thus, as it were, to integrate the computer into the device 1.

The method according to the invention is probably the most effective of all known EDP-supported learning methods for learning to tee off a golf ball, since it combines mathematical recording and analysis with pictorial representation in the best possible way. In terms of the achievable learning effect, it is by far the easiest method to carry out. After a short training a user is able to work as intended by means of the device according to the invention, without having to continue to take a trained person to complete.

The optical method described in detail for measuring the position of the golf club is currently the most suitable detection method for this purpose, and it is particularly well combined with the inventive use of light beams to indicate the position and orientation of the golfer or position and tee of the golf ball since, apart from the obvious internal electronic signal processing, only optical methods are used for signal and measuring methods.

However, the golfer's position and orientation display method and the position and tee direction of the golf ball are also applicable regardless of the measuring method for detecting the position of the golf club.

Claims (15)

1. Apparatus for the detection and analysis of the motion of a golf club used to strike a golf ball, whereby the apparatus comprises one or multiple signal sources, a stationary device and one or more detectors and whereby the one or multiple signal sources can be situated on the golf club and whereby the one or multiple detectors are situated on the stationary device and are capable of detecting the position of the signal sources relative to themselves
   such that
   the stationary device (1), which contains the one or multiple detectors (1.1), also houses one or multiple light sources (1.3, 1.4), which emit one or multiple focussed light beams (1.3.1, 1.4.1), which each create a spot of light on a surface that they strike, which serves as a marker for the placement of the feet of the golf player and/or for the placement of the golf ball to be struck.
2. Apparatus according to claim 1, such that light pulses are sent from at least two points on the golf club situated at a distance from each other, whereby the light pulses can be associated with these individual points and are detected by two detectors (1.1) situated at a distance from each other in a stationary device (1), whereby the position of the emitting points and thereby the position and orientation of the golf club can be calculated based on the incident angles at the individual detectors and whereby on the basis of a rapid sequence of such measurements and associated calculations, the path of motion of the golf club is recorded as a sequence of individual position measurements taken at defined points in time.
3. Apparatus according to claim 1 or 2 such that the shape of the light spot created by the light beam (1.3.1, 1.4.1) indicates the orientation of the golf player and/or the desired striking direction of the golf ball.
4. Apparatus according to one of the above claims such that a light source (1.3, 1.4) is supplemented by a laser distance measurement that measures the distance from the point at which the respective light beam (1.3.1, 1.4.1) strikes a surface to the stationary device (1).
5. Apparatus according to one of the above claims such that a camera (1.2) is installed in the stationary device (1) for recording a video or a series of photographs of the golf player.
6. Apparatus according to one of the above claims such that the stationary device (1) is situated on a stand (4), whereby the connection between the stand and the device can be switched between a tilting state and a fixed state and such that the stationary device (1) is equipped with a mechanism for measuring its inclination.
7. Apparatus according to one of the above claims such that the stationary device (1) has on its top side an at least approximately level and at least approximately horizontal surface (1.5) on which a portable computer can be placed and such that the stationary device (1) is equipped with an interface for bidirectional data transmission with a computer.
8. Apparatus according to one of the above claims such that a golf club (3) is equipped with a transmission component (2), which consists of a oblong mounting element (2.1), which runs along the shaft (3.2) of the golf club and is fastened to this in a removable fashion, and such that two signal emitters (2) suitable for the emission of light signals are situated on the oblong mounting element (2.1) at a distance from each other lengthwise along the shaft (3.2) of the golf club.
9. Apparatus according to claim 8 such that the signal emitters (2.2) have multiple emission points for light distributed around the circumference of the shaft (3.2) of the golf club.
10. Process for detecting and analysing the motion of a golf club used to strike a golf ball, whereby signal sources on the golf club send signals that are received by detectors on a stationary device and whereby the position of the signal sources relative to the detectors is determined based on the signals received
    such that
    from the stationary device (1), which contains detectors (1.1), one or more focussed light beams (1.3.1, 1.4.1) are emitted, which each create a spot of light on a surface that they strike, which serves as a marker for the placement of the feet of the golf player and/or for the placement of the golf ball to be struck.
11. Process according to claim 10, such that light pulses are sent from at least two points on the golf club situated at a distance from each other, whereby the light pulses can be associated with these individual points and are detected by two detectors (1.1) situated at a distance from each other in a stationary device (1), whereby the position of the emitting points and thereby the position and orientation of the golf club can be calculated based on the incident angles at the individual detectors and whereby on the basis of a rapid sequence of such measurements and associated calculations, the path of motion of the golf club is recorded as a sequence of individual position measurements taken at defined points in time.
12. Process according to claim 10 or 11 such that the distance from the point at which the respective light beam (1.3.1, 1.4.1) strikes a surface to the stationary device (1) is measured by a laser distance measurement and such that the information obtained in this way is used for the coordinate transformation of the measured motion curves to obtain a normalised depiction.
13. Process according to one of the claims 10 to 12 such that, in addition to the position measurement of the signal emitters, the golf player is filmed or photographed by a camera (1.2) installed on the stationary device (1), for which purpose the camera is focused and oriented in accordance with the spots of light created by the light beams (1.3.1, 1.4.1).
14. Process according to one of the claims 11 to 13 such that the signal emitters (2.2) have multiple emission points for light distributed around the circumference of the shaft (3.2) of the golf club and such that all emission points of a signal emitter (2.2) emit the same light signal.
15. Process according to one of the claims 11 to 13 such that the signal emitters (2.2) have multiple emission points for light distributed around the circumference of the shaft (3.2) of the golf club and such that all emission points of a signal emitter (2.2) emit light signals that can be differentiated from each other.

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