FR2962659A1 - Ball game e.g. tennis, learning method, involves providing accessory e.g. tennis racket, with emitting units to emit light beam, and forming luminous point on reference surface by lighting beam - Google Patents

Abstract

The method involves providing an accessory (2) e.g. tennis racket, with emitting units to emit a light beam (3). A luminous point (13) is formed on a reference surface (5) by the lighting beam, where the luminous point is formed near reference zones (6, 7). A warning signal is determined by a generating unit when an optical detection unit detects a light (14) of the lighting beam reflected by the reference zones. An independent claim is also included for a device for learning a ball game.

Description

1 METHOD OF LEARNING BALL GAME AND LEARNING SYSTEM OF CORRESPONDING BALL GAME.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method of learning a ball game and the learning system of a corresponding ball game.

BACKGROUND ART OF THE INVENTION. Such methods and systems are known per se in the field of sports. The patent application FR2702385, published on September 16, 1994 in the name of R. MASIP, describes in particular an apparatus for facilitating and improving the tennis service loop. The device allows you to launch a solid and then bring it back to you. It essentially comprises a handle or handle, to which is attached, by means of a filamentary link, the solid to be thrown. This link slides in a channel that passes through the handle or the handle. The device can also be used to repeat the "Drive" golf, as well as the "Smash" tennis, badminton or squash. This device has the advantage of being very simple and robust, but does not use all the resources of modern technology. On the other hand, the laser baseball bat described in US Pat. No. 6,177,0002, published August 3, 2004 in the name of C. AIGOTTI, uses optical fibers to create one or more light beams. These beams emerge either along the axis of the bat, or perpendicular to it. They allow the player, or his coach, to check that the position of the bat is correct with respect to the ball. This device allows the player to improve the placement of the bat with respect to the ball, but does not necessarily allow him to acquire the correct movement. US Patent Application US20060058122, published March 16, 2006 in the name of J. R. COX, provides a partial solution to this problem. A laser beam emitted in the axis of the baseball bat forms a bright spot on the ground. In this way the player, or his coach, can visualize the movement of the bat and make corrections. A wire representing the ideal movement may be placed on the playing field, or a straight line may be painted. The principle described may also apply to golf. -2- This last device solves the problem of the correction of the absolute position of the bat in space, without however solving that of the correction of the relative position of the player and the bat. In addition, the player is forced to keep his gaze turned towards the ground to observe the trajectory of the light point. There remains therefore a need for a method and a system for learning a game of ball to overcome the disadvantages and limitations of the state of the art, especially for games other than baseball or golf.

GENERAL DESCRIPTION OF THE INVENTION The present invention therefore aims at a method of learning a ball game such as those consisting at least of sending a ball by means of a hand held accessory. It is precisely a method of the type consisting in providing this accessory means for transmitting at least one light beam and dedicated in a remarkable manner to tennis. Preferably, the method according to the invention consists of forming, by this light beam, at least one luminous point on a reference surface. According to another characteristic of the method, the luminous point is advantageously formed in the vicinity of at least one reference zone. It will be benefited by the fact that the method according to the invention consists in additionally providing the accessory with means for determining the membership of the luminous point in the reference zone. Advantageously, the method consists in providing in addition this accessory 25 warning means of a player using the state of the determination means. The invention also relates to a system for learning a ball game such as those consisting at least of sending a ball by means of a hand held accessory. The system in question is of the type where this accessory is provided with means for emitting at least one light beam. The learning system of a ball game according to the invention is remarkable in that the accessory is a tennis racket. Preferably, in the system according to the invention, this light beam forms at least one luminous point on a reference surface. Advantageously, this reference surface comprises at least one reference zone of at least one position of the light spot and furthermore comprises at least one reference location of a player using the racket. This reference zone preferably comprises a retro-reflective material. It will be benefited by the fact that the racket comprises optical detection means and means for generating a warning signal when these optical detection means detect a light of the light beam reflected by the reference zone. These few essential specifications will have made obvious to the skilled person the advantages brought by this method and system of learning a game of ball compared to the state of the prior art. The detailed specifications of the invention are given in the following description in conjunction with the accompanying drawings. It should be noted that these drawings have no purpose other than to illustrate the text of the description and in no way constitute a limitation of the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figures 1a and 1b show two exemplary embodiments of the method of learning a ball game according to the invention. Figures 2a, 2b and 2c show three preferred embodiments of the tennis racket of the ball game learning system according to the invention. Fig. 3 is a block diagram showing the electronic elements of the third preferred embodiment of the tennis racket of the ball game learning system according to the invention shown in Fig. 2c.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION The method allows very fast learning of tennis by workshops, for beginners of all ages. References to Figures 1a and 1b will provide a good understanding of the principle of this method and the equipment used. The tennis player - the student - 1 holds in his hand a tennis racket 2 specially designed, or of a modified standard type, to emit light beams 3. -4- These light beams 3 are emitted in the plane of the racket 2, as shown in Figure la, or, alternatively, perpendicular to the plane of the racket 2, as shown in Figure 1 b. In the first case (Figure la), at the end of the preparation for the reception or the sending of the ball 4, the student 1 places the racket 2 so that the light beams 3 projected on the ground 5 are directed towards a 5. At the moment of the racket 2 / ball 4 impact, the pupil moves the racket 2 so that the light beams 3 remain directed to drawings or photographs of 7 balls placed at the racquet 2. floor 5 and distributed along a trajectory corresponding to a movement 8 whose basic principles are respected. The second case (FIG. 1b) enables the pupil 1 to practice blank gestures or exchanges of balls 4 against a wall 9, the trace 10 of the plurality of the light beams 3 on the wall 9 reproducing the 11 As shown in FIG. 1a, drawings or photographs of feet 12 are preferably placed on the ground 5 in order to show the correct position of the latter during the exercise. Preferably, the learning method according to the invention also offers the pupil 1 the possibility of controlling himself the correct execution of the exercise by providing him with a return in the form of a sound signal, or a vibration of the handle of the racket 2, when the light beams are in good position on the reference areas 6, 7 formed by the images of the racket 6 and balls 7 at the beginning and during the exercise. As will be explained in detail in connection with FIG. 3 below, the determination of whether the light spots 13 formed on the ground 5 belong to the reference zones 6, 7 is made possible by the detection reflected light 14 by these reference areas 6, 7 in the most complete embodiment of the invention. The learning system according to the invention is in fact divided into three preferred embodiments: a first embodiment shown in FIG. 2a comprising only light beams 3 emitted in the plane of the frame 11 of the racket 2 ; A second embodiment shown in FIG. 2b further comprising light beams 3 emitted perpendicularly to the plane of the frame 11 of the racket 2; a third embodiment shown in FIG. 2c further comprising optical detection means. In the first embodiment (FIG. 2a), the light beams 3 are emitted by first laser diodes 15, two in number, arranged on one side of the frame 11 in a position symmetrical with respect to the minor axis of the schematizing ellipse. the frame 11, and whose transmission direction is parallel to this minor axis. These first laser diodes 15 are miniature models emitting in the visible spectrum (preferably at 650 nm, that is to say in red light) within a power limit authorized for public use without any particular precaution (1 mW at most in France). They are each preferably provided with a collimation optics 15 making it possible to adjust the collimation of the emitted beam, that is to say the size of the light spot produced on the reference surface 5, 9, and of a circuit integrated power control. The first laser diodes 15 are powered by batteries or batteries 16 arranged preferably in the handle 17 of the racket 2. A push-button switch 18 arranged at the end of the handle 17 allows it to be switched on and off. Very remarkably, the first two laser diodes 15 are separated by a distance D substantially equal to the average diameter of a tennis ball 4, that is to say by a distance of the order of 65 mm. This characteristic 25 makes it possible to pinpoint very precisely the position of the racket 2 above the images of the balls 7: the light spots 13 formed by the parallel beams 3 on the ground 5 are simultaneously inside the images of the balls 7 when the position is correct. In the second preferred embodiment of the invention (Figure 2b), the frame 11 of the racket 2 further comprises second laser diodes 19, preferably six in number, advantageously of the same type as the first 15, distributed along the frame 11. Their transmission direction is perpendicular to the plane of the frame 11 or the sieve of the racket 2. These second laser diodes 19 are also powered by the batteries or batteries feeding the first laser diodes 15. A switch 20 arranged at the end of the handle 17 allows the starting of one or other of the sets of laser diodes 15, 19, and stopping. The third preferred embodiment of the invention (FIG. 2c) further comprises first and second laser diodes 15, 19 of the previous preferred embodiments, a photodiode 21 arranged on the frame 11, as well as an electronic processing block. 22 and a transducer 23 placed in the handle 17. The photodiode 21 located on the frame 11 between the first laser diodes 15 makes it possible to detect the light reflected or scattered when the image of the racket 6 and the images of the balls 7 are illuminated by the first laser diodes 15. For the implementation of the learning method according to the invention, the reflection and / or diffusion characteristics of the reference zones 6, 7 must of course be different from those of the ground 5. Preferably, these reference areas 6, 7 therefore comprise at the surface a retro-reflective material, that is to say which reflects the light in the direction of incidence, and not according to an angle of incidence. the reflection equal to the angle of incidence. This material may be that used, for example, for safety vests, or be made of glass microbeads in a varnish. In the latter case, the drawings and photographs of the racket 6 and balls 7 are covered with this varnish. The reference surface 5 advantageously consists of a floor mat 5 carrying the reference areas 6, 7 as well as the reference locations 12 for the feet of the pupil 1. The drawings and photographs of the rackets 6, Bales 7, feet 12 are alternatively very advantageously provided in the form of stickers to be placed on the floor 5 or a carpet 5. FIG. 3 shows in detail all the electronic elements allowing the determination of membership, or no, light spots 13 formed by the first laser diodes 15 to the reference areas 6, 7. Command signals El, E2 produced by two oscillators 24 of the electronic processing block 30 modulate the power of the beams 3 of the laser diodes 15 via their integrated power control modules with two different modulation frequencies F1 and F2. The photodiode 21 receives the ambient light, but no reception signal R at the modulation frequency F1 or F2, if none of the beams emitted by the first 35 laser diodes 15 is reflected by the reference zones 6, 7. 7- photodiode 21 receives a single reception signal R at the modulation frequency F1 or F2, if only one of the beams 3 strikes the reference areas 6, 7. The photodiode 21 simultaneously receives reception signals R at the IF modulation frequencies and F2 when the beams 3 simultaneously hit the reference areas 6, 7, that is to say in particular when the racket 2 is placed above and exactly astride the bale path 7. In a manner known per se, the signal R-receiver of the photodiode 21 is amplified and filtered by a receiving module 25 at high gain eliminating the DC component due to ambient light and parasitic frequencies. The sensitivity of the system is improved by providing the photodiode 21 with a collecting optics and an optical filter centered on the emission wavelength of the first laser diodes 15. The reception signals at the modulation frequencies F1 and F2 are detected by two decoders 26 and their simultaneity is determined by a logic gate 27. Depending on the result of the determination, a warning signal S is generated. This warning signal S preferably triggers a vibrator motor 23 of the type used in mobile phones arranged in the handle 17. Alternatively, the warning signal S triggers an audible signal produced by a transducer 23, a loudspeaker. or piezoelectric vibrator, preferably arranged in the heart of the racket 2. The pupil 1 is thus warned of the correct positioning of the racket 2 and the perfect execution of the movement 8. It can correct itself if it does not perceive the vibration of the handle, or, alternatively, does not hear the audible signal 25 Alternatively, the electronic processing unit 22 indicates by a vibration of the handle the correct position of the racket 2 relative to the reference zones 6, 7, evaluates, for example by counting the number of zones overflown, the respect of the trajectory and triggers a sound signal in case of success. The modulation frequencies F1, F2 are chosen in a range that is compatible with the bandwidth of the power regulation modules of the laser diodes used, while being different from those of the possible parasitic light, and preferably between 30 KHz and 50. KHz. The control signals E1, E2 are advantageously periodically switched for a duration T by a sequencer circuit 28. This characteristic has the result of producing dashed trajectories when the light points 13 move on the reference surface 5. For a determined duration T, the length of this dotted line is proportional to the speed of the racket 2. For example, for a duration T of 0.1 s, the dotted lines have a length of 10 cm when the racket 2 is moved to 1 m / s.

This is additional information that allows the student 1 and his teacher to judge the correct execution of the movement 8. The electronic processing block 22 is made using conventional analog and / or digital techniques, which the person skilled in the art will easily choose according to the development tools at his disposal and his cost of production requirements. For example, the amplifier module 25 and the decoders 26 are advantageously receiving integrated circuits used for the transmission of data to the IrDA standard. It goes without saying that the invention is not limited to the only preferred embodiments described above. In particular, the use of second laser diodes 19 for the formation of the light beams 3 reproducing the shape of the frame 11 on the wall 9 is not limiting. Light bulbs or light-emitting diodes for projecting an image of the screen are, alternatively, used for the same purpose.

The numbers of the first and second laser diodes 15, 19 will be adapted by those skilled in the art according to the needs of the users of the system. The light beams 3 may be formed by light pipes from light sources located in one or more parts of the racket 2. The electronic processing block 22, a power supply unit 29 comprising the batteries or batteries 16 and an M / A control element 18, 20 are not limited to the handle 17. They are alternately arranged in other parts of the racket 2, in particular at the heart. The description above also applies to a set of elements 22, 23, 29, 30, 31 ready to mount, in particular by means of clips, and distributed commercially in the form of a "kit" for the transformation of a standard racket. The invention therefore embraces all the possible variants of embodiment to the extent they do not go beyond the scope of the claims below.

Claims (10)

CLAIMS1) A method of learning a ball game such as those consisting at least of throwing a ball (4) by means of an accessory (2) held in hand, said method being of the type consisting in providing said accessory (2) transmission means (15, 19) of at least one light beam (3), characterized in that said game of ball is tennis and said accessory a tennis racket. 2) A method of learning a ball game according to claim 1, characterized in that it consists in forming by said light beam (3) at least one light point (13) on a reference surface (5, 9). 3) A method of learning a ball game according to claim 2, characterized in that said light point (13) is formed in the vicinity of at least one reference area (6, 7). 4) A method of learning a game ball according to claim 3, characterized in that it further comprises determining a membership of said light point (13) to said reference area (6, 7) by providing more said racket (2) means for determining (21, 22) said membership. 5) A method of learning a game of ball according to claim 4, characterized in that it further comprises warn a player (1) using said racket (2) the state of said determination means (21, 22) by further providing said racket (2) with warning means (23) of said player (1). 6) Learning system of a ball game such as those consisting at least of throwing a ball (4) by means of an accessory (2) held in hand, said system being of the type where said accessory (2) is provided with emission means (15, 19) of at least one light beam (3), characterized in that said accessory is a tennis racket (2). 9 _ 10_ 7) Learning system of a ball game according to claim 6, characterized in that said light beam (3) forms at least one light point (13) on a reference surface (5, 9). 8) Ball game learning system according to claim 7, characterized in that said reference surface (5, 9) comprises at least one reference zone (6, 7) of at least one position of said light point (13) and further comprises at least one reference location (12) of a player (1) using said racket ( 2). 9) Ball game training system according to claim 8, characterized in that said reference area (6, 7) comprises a retro-reflective material. 10) Ball game learning system according to claim 9, characterized in that said racket (2) comprises optical detection means (21) and generation means (25, 26, 27) of a warning signal (S) when said optical detection means (21) detect a light (14) of said light beam (3) reflected by said reference area (6, 7).