WO2005094951A2

WO2005094951A2 - A system and a method for determining the activity of a golf player

Info

Publication number: WO2005094951A2
Application number: PCT/IB2005/050949
Authority: WO
Inventors: Peter T. S. K. Tsang; Carsten Heinks; Pieter G. Van Engen
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2004-03-31
Filing date: 2005-03-18
Publication date: 2005-10-13
Also published as: WO2005094951A3

Abstract

A system for determining the activity of a golf player (1), comprising means for detecting and recording the movement of the golf equipment (2,3). At least one stationary receiver (6) and preferably more than one receiver (6) is present for receiving signals from the golf equipment (2,3). Calculation means (8) are present for calculating the location and/or movement of the golf equipment (2,3) based on the received signals.

Description

A system and a method for determining the activity of a golf player

The invention is related to a system for determining the activity of a golf player, comprising means for detecting and recording the movement of the golf equipment, notably the golf club and/or the golf ball.

To evaluate the performance of a golf player, the swing (movement) of the golf club can be detected and recorded, as is described in GB-A-2377645. This publication discloses an instrumented golf club comprising a plurality of sensors, an internal power supply, an angular rate sensor and an internal ring buffer memory for detecting and capturing data related to the golf club swing. From time to time the captured data can be transferred from the golf club to computing means for processing the data and presenting the data in a useful and informative format. The data may be used to assist a golf player's swing, or to design an appropriate golf club for a specific type of golf player. The known systems for determining the activity of a golf player are less accurate or comprise relative voluminous and/or heavy devices which are attached to the golf equipment, so that the golf player cannot use equipment equal or similar to standard golf equipment.

The object of the invention is a system and a method for determining the activity of a golf player, whereby standard golf equipment can be used, or at least golf equipment having properties similar to standard golf equipment, and whereby an accurate detection of the swing of the golf player and/or the movement of the golf ball is possible. To accomplish with that object, at least one stationary receiver is present for receiving signals from the golf equipment, whereby calculation means are present for calculating the location and/or movement of the golf equipment based on the received signals. Preferably the signals are modulated signals. Said signals from the golf equipment, i.e. from the golf club and/or from the golf ball, can be signals that are reflected by the golf equipment or by parts of the golf equipment such as the club-head, whereby an external stationary signal emitter emits the signals towards the relevant golf equipment. Thereby, more stationary signal emitters can be present, each emitting a certain signal, which signals are received by the stationary receiver after they are reflected. Based on the received signals, the location of the golf equipment can be calculated. But preferably there are more than one stationary receiver present, whereby more stationary receivers can receive the same signal coming from the golf equipment. Preferably, the golf equipment is provided with one or more emitters for emitting said signals, which signals can be received by said stationary receivers. By dividing the determining system into two components, a main component comprising almost all detection and recording devices, and a small component comprising only a small emitter, an accurate measurement of the mutual distance and of a variation of that distance in the time, between the two components of the system is possible, whereby one of the components is relative small. Because the small dimensions of an emitter, the use of the golf equipment will not be influenced by the presence of the emitters, so that the golf equipment will be equal or similar to standard golf equipment. The signals can be sound signals (subsonic or sonic, but preferably ultrasonic) or light signals (visible light or ultraviolet light, but preferably infrared light), however, preferably the signals are electromagnetic waves, whereby the receivers can receive such waves. Preferably these waves have a radio frequency. The emitters can be provided with an internal power supply, but the emitters can also be passive responders, which have extremely small dimensions. Such a passive responder, or tag, is a known device; it emits an electromagnetic signal in response to a certain electromagnetic signal sent to it. A passive responder, which is attached to a golf ball, is described in for example US-A-2002/0177490. In one preferred embodiment, three stationary receivers are present on the ground near the golf ball before the ball is hit by the head of the golf club. Three receivers can accurately locate the source of the received signal in a 3D environment. Preferably, the distance between the golf ball and each of the receivers is between 0.2 m and 2 m, and more preferably between 0.3 m and 1 m. Preferably, three receivers are located at the comers of a triangle, preferably a substantially equilateral triangle, whereby the golf ball is located near the center of the triangle, preferably in the center of the triangle, before the golf ball is hit by the golf club. At such locations of the receivers the differences of the signals that are received by each of the receivers is relative large, whereby a good accuracy of the detection is achieved. Preferably the receivers are attached to a device to keep them in predetermined mutual positions, whereby preferably said device may also carry a tee for supporting the golf ball before it is hit by the head of the golf club. In one preferred embodiment, said device is a flexible mat that can be placed on the ground at the location where the golf ball is to be hit, in particular near the golf ball, preferably around the golf ball and preferably also under the golf ball before it is hit. The mat may consist of two parts, or even more parts, each comprising one or two receivers, so that the parts of the mats can be placed on the ground near the golf ball at predetermined positions with respect to the golf ball. The receivers can have a fixed and predetermined position with respect to each other. But in case their mutual positions are not fixed, preferably the receivers can emit and receive certain signals in order to calculate their positions with respect to each other. Such signals can be the same kind of signals that the receivers receive from the emitter at the golf equipment. In one preferred embodiment the golf club is provided with an emitter, which is preferably attached near the head of the golf club. Thereby the swing of the golf club can be tracked by detecting the path of the emitter by means of the three receivers. When the emitter emits a modulated signal which is received by the receivers, the location and/or the velocity (speed and direction) and/or acceleration of the emitter can be calculated based on the received signals. The Doppler effect may provide for a change in the received signal, and such change gives information about the speed of the emitter. The position of the golf club during the swing can also be determined in case more than one emitter is attached to the golf club. Information about said position is not necessary for determining the main characteristics of the swing, but it can be helpful for analyzing the performance of the golf player in more detail. Preferably, the golf ball is provided with a passive responder, or tag, which responder emits a signal after it is energized by electromagnetic radiation. Such radiation can be sent out by emitting means in or near one of the stationary receivers. In one preferred embodiment, the golf club and/or the golf ball is provided with more than one emitter, preferably more than one passive responder. More emitters in the golf ball enable to determine not only the path of the golf ball, but also the spin of it, which is an important aspect of the movement of the golf ball. It will not always be possible to track the whole path of the golf ball, because the distance between the receivers and the golf ball may become too large during its movement. However, information about the first part of its movement enables a valuable analysis of the effect of the hit. A golf ball provided with a passive responder is described in US-A-

2002/0177490. According to that publication, a passive responder, which has a very small mass and dimension, is embedded in a golf ball. The passive responder has negligible influence on the weight and flight dynamics of the golf ball and can withstand the extreme acceleration and impact of the golf ball. According to the publication the passive responder enables to identify the location of the golf ball in order to collect the golf balls after the game. The invention is furthermore related to a method for determining the activity of a golf player, whereby the movement of the golf equipment is detected and recorded. The method is characterized in that stationary receivers receive signals from the golf equipment, whereby the location and/or movement of the golf equipment is calculated based on the received signals.

The invention will now be further elucidated by means of a description of an example of an embodiment of the system for determining the activity of a golf player, whereby reference is made to the drawing comprising figures, which are only diagrammatic representations, in which: Fig. 1 shows a playing golf player; Fig. 2 is a perspective view of a mat comprising parts of the system; and Fig. 3 is a top view of the mat shown in Fig. 2.

Figure 1 shows a golf player 1 who is starting to swing the golf club 2, in order to hit the golf ball 3. The swing, i.e. the path of the golf club 2, is indicated with the striped line 4. The golf ball 3 is present on the central part of a rectangular mat 5 lying on the ground in front of the golf player 1. The mat 5 furthermore carries three receivers 6, positioned at the corners of an equilateral triangle, whereby the golf ball 3 is positioned in the middle of that triangle. The mat 5 is thin and flexible, but also rather stiff, so that the three receivers 6 have fixed and predetermined positions relative to each other and with respect to the golf ball 3 when the mat 5 is lying on the ground. Figures 2 and 3 represent the mat 5 in perspective view and in top view respectively, whereby also an electronic device including power supply 8 in the mat 5 is shown, as well as a radiation device 1 1. The three receivers 6 and the radiation device 11 are electrically connected with the electronic device 8 through metal wires in the mat 5. Figure 2 shows a tee 9, which tee is attached to the mat and can support the golf ball 3. By means of the mat 5 the three receivers 6 and the tee 9 have predetermined positions with respect to each other. Figure 1 shows furthermore a system of coordinates comprising an X-axis, a Y-axis and a Z-axis, which three coordinate axes are positioned perpendicular with respect to each other. Every point in the space around the mat 5 can be represented in a value at each of the three axes, and the golf ball 3 is located in the point 0,0,0, near the middle of the three receivers 6. An emitter 10 is attached to the golf club near the head of it. The emitter 10 emits out a modulated signal at a fixed radio frequency. When the golf club 2 moves, the signals received by the three receivers 6 differs in time slightly, and at any time the distances to each of the receivers 6 can be determined based on the received signals. In this manner the swing of the golf club 2, i.e. the path of the emitter 10, can be determined and recorded. The data received by the three receivers 6 is transferred to the microprocessor 8, which carries out all the calculations to determine the path of the emitter 10. Microprocessor 8 can be provided with memory means to store the calculated information, or it can send the data to an external memory and/or display to show the results of the determination. The mat 5 can be a rectangular mat as shown in the figures, but it can also consist out of two separated parts, so that it can be placed on both sides of the golf ball 3. This may be necessary after the tee shot, when the golf ball 3 is lying on the ground (in the grass or so). The determination system may store the swing characteristics of the golf player 1 and compares them with swing data taken from a professional or star player stored in the memory of the system. By superimposing the two swing data together, the golf player 1 can see how close he is to a perfect swing. The data of the swing of star players can be stored in the microprocessor 8. In this manner the system is a coaching device. The golf ball 3 is provided with two passive responders, or tags, being located near the surface of the ball at opposite sides of the ball. Each passive responder emits a signal with a specific frequency when the responders receive certain radiation from an external source. Said radiation is sent out by radiating device 1 1 at the mat 5. The radiation device 1 1 is controlled by the microprocessor 8, and the signals from the passive responders in the golf ball 3 are received by the receivers 6. Based on these signals, the microprocessor 8 can calculate the movement of the golf ball 3, i.e. its location and its speed and its spin, at least in the first part of its path. So, not only the swing of the golf club 2 is determined and recorded, but also the results of the swing, i.e. the movement of the golf ball 3 after it is hit by the head of the golf club 2. In the described example of an embodiment, the signals are electromagnetic signals. However, other kind of signals can be used in other embodiments of the invention. For example, the head of the golf club 2 and/or the golf ball 3 can reflect ultrasonic or infrared flashes coming from a stationary source. The described embodiment of the determination system is only an example; a great many other embodiments are possible.

REFERENCE NUMBERS:

1 golf player

2 golf club

3 golf bail

4 swing (striped line)

5 mat

6 three receivers

7

8 electronic device

9 tee

10 emitter on golf club 2

11 radiation device

Claims

CLAIMS:

1. A system for determining the activity of a golf player (1), comprising means for detecting and recording the movement of the golf equipment (2,3), whereby that at least one stationary receiver (6) is present for receiving signals from the golf equipment (2,3), whereby calculation means (8) are present for calculating the location and/or movement of the golf equipment (2,3) based on the received signals.

2. A system as claimed in claim 1 , characterized in that more stationary receivers (6) are present, preferably three stationary receivers (6).

3. A system as claimed in any one of the preceding claims, characterized in that golf equipment (2,3) is provided with an emitter (10) for emitting said signals, which signals can be received by said stationary receivers (6).

4. A system as claimed in any one of the preceding claims, characterized in that the signals are electromagnetic waves, and in that the receivers (6) can receive such waves.

5. A system as claimed in any one of the preceding claims, characterized in that more stationary receivers (6), preferably three, are present on the ground near the golf ball (3) before the ball is hit by the head of the golf club.

6. A system as claimed in any one of the preceding claims, characterized in that three receivers (6) are located at the corners of a triangle, preferably a substantially equilateral triangle, whereby the golf ball (3) is located near the center of the triangle, preferably in the center of the triangle.

7. A system as claimed in any one of the preceding claims, characterized in that the receivers (6) are attached to a flexible mat (5) that can be placed on the ground at the location where the golf ball (3) is hit.

8. A system as claimed in any one of the preceding claims, characterized in that the receivers (6) can emit and receive certain signals in order to calculate their positions with respect to each other.

9. A system as claimed in any one of the preceding claims, characterized in that the golf club (2) is provided with an emitter (10).

10. A system as claimed in any one of the preceding claims, characterized in that the golf ball (3) is provided with a passive responder.

11. A system as claimed in any one of the preceding claims, characterized in that the golf club (2) and/or the golf ball (3) is provided with more than one emitter, preferably more than one passive responder.

12. A method for determining the activity of a golf player, whereby the movement of the golf equipment (2,3) is detected and recorded, whereby that stationary receivers (6) receive signals from the golf equipment (2,3), whereby the location and/or movement of the golf equipment (2,3) is calculated based on the received signals.