U.S. patent application number 11/460573 was filed with the patent office on 2007-03-15 for device and method for measuring a rotational frequency of a movable game device.
Invention is credited to Walter Englert, Udo Kuenzler.
Application Number | 20070059675 11/460573 |
Document ID | / |
Family ID | 36926304 |
Filed Date | 2007-03-15 |
United States Patent
Application |
20070059675 |
Kind Code |
A1 |
Kuenzler; Udo ; et
al. |
March 15, 2007 |
Device and method for measuring a rotational frequency of a movable
game device
Abstract
For measuring the rotational frequency of a movable game device,
one resorts to an existing radio signal in the form of a broadcast
signal or mobile communication signal within the framework of an
open system, or to a radio signal of an evaluation unit within the
framework of a closed system, so as to obtain, by means of an
antenna having a directivity characteristic, a time-varying radio
antenna receive signal which has a low-frequency modulation
portion, the frequency of which corresponding to the rotational
frequency of the movable game device.
Inventors: |
Kuenzler; Udo; (Karlsbad,
DE) ; Englert; Walter; (Burgrieden, DE) |
Correspondence
Address: |
GLENN PATENT GROUP
3475 EDISON WAY, SUITE L
MENLO PARK
CA
94025
US
|
Family ID: |
36926304 |
Appl. No.: |
11/460573 |
Filed: |
July 27, 2006 |
Current U.S.
Class: |
434/251 |
Current CPC
Class: |
A63B 41/00 20130101;
A63B 43/00 20130101; A63B 71/0605 20130101; A63B 2225/30 20130101;
A63B 2220/833 20130101; G01S 13/862 20130101; A63B 69/002 20130101;
A63B 2225/50 20130101; G01S 13/74 20130101; A63B 2225/52 20130101;
A63B 2220/40 20130101 |
Class at
Publication: |
434/251 |
International
Class: |
A63B 69/00 20060101
A63B069/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 29, 2005 |
DE |
102005036355.5 |
Claims
1. A device for measuring a rotational frequency of a movable game
device using a high-frequency radio signal, the device comprising:
a provider for providing a time-varying radio antenna receive
signal; and a detector for detecting a low-frequency frequency,
which has been modulated onto the high-frequency radio signal,
using the time-varying radio antenna receive signal, the
low-frequency frequency of the time-varying radio antenna receive
signal representing the rotational frequency of the movable game
device.
2. The device as claimed in claim 1, wherein the provider comprises
a radio antenna designed for a frequency band used by a
broadcasting signal or television signal or mobile communication
signal, and which has a radiation characteristic which deviates
from an ideal isotropic radiator, so that a rotation of the radio
antenna provides a high-frequency carrier signal having a
low-frequency modulation portion.
3. The device as claimed in claim 1, wherein the provider comprises
a selector for selecting a low-frequency modulation portion.
4. The device as claimed in claim 3, wherein the detector is
configured to determine a frequency of the low-frequency modulation
signal as the rotational frequency.
5. The device as claimed in claim 1, wherein the detector comprises
an extreme-value detector or zero-crossing detector and a
chronometer to determine a time duration between two extreme values
or between an extreme value and a zero crossing, and to determine
the rotational frequency from the time duration.
6. The device as claimed in claim 1, wherein the detector is
configured to suppress a carrier frequency of a high-frequency
electromagnetic field to extract a low-frequency modulation
portion.
7. The device as claimed in claim 1, wherein the detector is
configured to detect a low-frequency envelope of the radio antenna
receive signal.
8. The device as claimed in claim 1, wherein the provider is
configured to provide a radio antenna receive signal having two
channels, a first channel representing a radio signal of a first
receive antenna, and a second channel representing a receive signal
of a second receive antenna having an antenna characteristic which
differs from an antenna characteristic of the first antenna.
9. The device as claimed in claim 8, wherein the first radio
antenna comprises a first antenna characteristic having a first
direction of the highest sensitivity, and wherein the second radio
antenna comprises a second antenna characteristic having a second
direction of the highest sensitivity, wherein the first and second
directions differ from each other.
10. The device as claimed in claim 9, wherein a difference in the
directions of the highest sensitivities is present which lies
within a range of angles between 70.degree. and 110.degree..
11. The device as claimed in claim 1, wherein the provider
comprises a dipole antenna or a ferrite antenna or a mobile
communication antenna.
12. The device as claimed in claim 1, wherein the provider is
designed for a long-wave band, a medium-wave band or a short-wave
band.
13. The device as claimed in claim 1, which is mechanically
connected to the movable game device and further comprises an
output interface for transferring a piece of information indicating
the rotational frequency to a receiver.
14. The device as claimed in claim 1, the provider being
mechanically connected to the movable game device, and the detector
being located at a distance from the movable game device, the
movable game device comprising an output interface for transferring
the time-varying radio antenna receive signal to the detector, and
the detector which is located at a distance comprising a receive
interface to receive a signal stemming from the output interface of
the movable game device.
15. The device as claimed in claim 1, which is configured at a
distance from the movable game device, the provider being an input
interface to receive a signal which stems from the movable game
device and which comprises information about the time-varying radio
antenna receive signal.
16. The device as claimed in claim 1, further comprising: a
transmitter for transmitting information to an external
transmitter, the information causing the external transmitter to
radiate a radio transmit signal, the provider comprising a receive
antenna, and the transmitter being configured to use the receive
antenna when transmitting the information.
17. The device as claimed in claim 8, the detector being configured
to receive the first and second channels and to select the channel
having a higher LF amplitude within a range smaller than 150
Hz.
18. The device as claimed in claim 1, wherein the provider is
configured to provide a broad-band radio antenna receive signal
comprising several high-frequency carriers modulated using low
frequencies, wherein the provider is configured to select an LF
component which occurs in several modulated high-frequency
carriers.
19. The device as claimed in claim 1, wherein the provider is
configured to provide a high-frequency radio antenna receive signal
or a low-frequency radio antenna receive signal.
20. The device as claimed in claim 1, wherein the provider or the
extractor is configured to extract a low-frequency portion having a
frequency of less than 100 Hz.
21. A method of measuring a rotational frequency of a movable game
device using a high-frequency radio signal, the method comprising:
providing a time-varying radio antenna receive signal; and
detecting a low-frequency frequency, which has been modulated onto
the high-frequency radio signal, using the time-varying radio
antenna receive signal, the low-frequency frequency of the
time-varying radio antenna receive signal representing the
rotational frequency of the movable game device.
22. A movable game device comprising: a radio antenna for providing
a time-varying radio antenna receive signal having a high-frequency
carrier portion and a low-frequency modulation portion; a selector
for extracting the low-frequency modulation portion; and an
interface for outputting the selected low-frequency modulation
portion.
23. The movable game device as claimed in claim 22, further
comprising: a detector for detecting a low-frequency frequency,
which has been modulated onto the high-frequency radio signal,
using the time-varying radio antenna receive signal, wherein the
interface is configured to transfer information about a frequency
underlying the low-frequency modulation portion instead of a time
curve of the selected low-frequency modulation portion.
24. The movable game device as claimed in claim 22, further
comprising: a transmitter for transmitting information to an
external transmitter, the information causing the external
transmitter to radiate a radio transmit signal, the provider
comprising a receive antenna, and the transmitter being configured
to use the receive antenna when transmitting the information.
25. A computer program having a program code for performing the
method of measuring a rotational frequency of a movable game device
using a high-frequency radio signal, the method comprising:
providing a time-varying radio antenna receive signal; and
detecting a low-frequency frequency, which has been modulated onto
the high-frequency radio signal, using the time-varying radio
antenna receive signal, the low-frequency frequency of the
time-varying radio antenna receive signal representing the
rotational frequency of the movable game device, when the program
runs on a computer.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from German Patent
Application No. 102005036355.5, which was filed on Jul. 29, 2005,
and is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to movable devices and in
particular to game devices such as balls, and to concepts for
measuring a rotational frequency of a movable game device.
[0004] 2. Description of Prior Art
[0005] For quite some time, various interest groups have wished to
study and understand the sequence of movements of moving objects
and/or persons, which requires an exact indication of the object's
position in space and time. What is of particular interest here
are, among other things, game balls, in particular in
commercialized types of sport, such as footballs, or soccer balls,
which are highly accelerated in three-dimensional space, as well as
tennis or golf balls. The question of who was the last to touch the
object of the game, how it was hit and in which direction it was
accelerated further may be decisive for the outcome of the game,
depending on the type of game.
[0006] Game devices that are used in high-performance sports, such
as tennis balls, golf balls, footballs and the like, nowadays can
be accelerated to extremely high speeds, so that the detection of
the object during the movement requires highly sophisticated
technology. The technical means employed so far--mainly
cameras--either completely fail to meet the requirements set forth
above, or meet them only to an insufficient degree; also the
methods, hitherto known, for position finding by means of various
transmitter and receiver combinations still leave a large error
margin with regard to the spatial resolution of the position
indication, with regard to the ease of use of the
transmitter/receiver components required, and above all with regard
to evaluating the data obtained by means of the
transmitter/receiver system, so that it is not yet possible, or at
least requires a large amount of effort, to evaluate the results
obtained from this data as fast as possible.
[0007] It is not only in the field of commercial sports, where
movable game devices may be employed, but it is also in the
personal field that users have become more and more used to
electronic devices indicating various pieces of information to give
a user feedback as to how he/she has affected an object, or to
provide him/her with information about how a player has affected a
gaming device.
[0008] Current statistics methods in commercial applications, such
as of the German first football division (Bundesliga), work with
recording relatively simple statistics, such as the percentage of
ball contacts of a team or the number of corners, free kicks or
fouls.
[0009] On the other hand, there have been means, for example in
tennis, where there is a very plannable, clearly arranged
environment with only two players, which measure, for example, the
speed of the tennis ball at the serve, such that a viewer is in a
position to assess whether a serve was "hard" or "soft".
[0010] What is problematic about such speed measurements which may
occur by optical methods is the fact that they do not function
within an environment where there is a muddle of players, such as
on a football pitch where there are not only two persons being
active, but 22 persons, who, in addition--unlike in tennis for a
serve--are not positioned in more or less the same place but may
form any constellation on the pitch. On the other hand,
particularly in football, it is interesting, both for the feedback
of the players in training and for the viewers to know, for
example, how a shot actually came about and/or how large the force
of the shot was.
[0011] Thus, kicking a ball in football or soccer or hitting a ball
in tennis represents the actual "base" impact, as it were, on the
game device which is always decisive of how the game continues,
since ultimately everything is about doing something with the
movable game device, such as playing it into an opponent's field
(as in tennis) or moving it into a goal (as in football, or soccer)
or into a basket (as in basketball) or to cause it to contact the
floor of the opponent's pitch (as in volleyball). Due to the
difficulty of the continuously changing constellations in dynamic
games, in particular team games, however also in tennis when no
serve is currently played, but the ball is played in one move,
external speed measurements will fail, which has lead to the fact
that there are currently no shot force detection systems that could
be employed in a flexible manner.
[0012] On the other hand, for the field of sports, but also for the
field of leisure, there is a further limitation resulting from the
fact that these fields are highly commercialized. All systems
providing additional information, in particular when they are
intended for leisure of for leisure sports, must enable to be
offered at a low price since they are objects which a user never
"absolutely needs" but might like to have anyway. Particularly in
such a market, it is decisive to be able to offer a robust system
at low price. For example, a system must not require a high level
of maintenance or of equipment such as, for example, a speed
measurement system for measuring the serve of a tennis player. Due
to the relatively high cost associated, a small tennis club would
never acquire such a system for training purposes, which applies
even more to a private person who wishes to play tennis in a
slightly more ambitioned manner in his/her leisure time.
[0013] When considering the impact experienced by a game device,
such as when it is shot by a racket or a leg or an arm or a hand of
a player, one will find that most of the time, the movable game
device will be made to rotate. Part of the energy transmitted to
the device is thus converted into rotational energy rather than
into, e.g., kinetic or potential energy. This rotation of the
movable game device has a considerable effect with regard to a
trajectory of the movable game device, since a trajectory thereby
may be influenced in that the trajectory will deviate from a normal
trajectory which would be followed, e.g., by a non-rotating object
in the air. In football, one knows of so-called "curling crosses"
which occur due to the fact that a ball rotates in the air and its
trajectory is influenced by the rotation. One also knows of free
kicks which are lowered down into the goal after they have passed
the wall and represent a challenge for each goal keeper. Here, too,
the rotation of the game device plays an important part.
[0014] A further decisive part is played by a rotation when the
rotating object hits the ground. Everybody knows this phenomenon
for example in table tennis, tennis or even football. The ball will
jump off differently when it is rotating than when it is not
rotating. Thus, a so-called "stopped" ball in tennis will hardly
continue its direction of flight once it bounces on the ground, but
will be highly decelerated and then tend to jump off high and thus
contribute to the opponent's confusion. On the other hand, an
accelerated ball will, when it hits the ground, jump off at a very
much smaller angle with the floor and in a highly accelerated
manner, which results solely from the rotation of the ball.
[0015] Measuring a rotation of a movable game device is thus a good
measure of being able to predict the behavior of a movable game
device or to receive feedback or to accumulate further statistical
data with regard to, e.g., a football match in terms of which
player not only has the hardest shot but may also give a ball the
highest level of rotation when he/she shoots.
[0016] U.S. Pat. No. 6,151,563 discloses a device for measuring a
movable object such as a baseball, football, hockey puck, football,
tennis ball, bowling ball or golf ball. A detection unit mounted to
the ball includes a spin detection circuit, an electronic processor
circuit, a magnetic field sensor and a radio transmitter. A
monitoring unit is worn, or carried, by a user and serves as a user
interface for the detection device. The monitoring unit has a radio
receiver, a processor, a keyboard and an output display displaying
various movement characteristics measured of the movable object,
such as flying time, speed, height of trajectory, spin rate or
curve of the movable object. Particularly, a spin detection is
performed in that a measurement of the earth's magnetic field is
performed using a magneto-inductive sensor, which is an inductive
element within an oscillator. If the sensor rotates by 1800
relative to the earth's magnetic field, a frequency shift of the
oscillator of up to 100% may be achieved. Thus, the frequency of
the oscillator tuned by the variable inductance is varied between a
maximum and a minimum value, an interval being measured between
frequency peaks to determine the spin rate of the object.
[0017] What is disadvantageous about this concept is the fact that
the entire detection is based on the earth's magnetic field which
may vary considerably from area to area and thus will lead to a
pronounced or weak frequency variation, depending on the intensity
of the earth's magnetic field.
[0018] In addition, measuring the earth's magnetic field requires a
lot of effort, particularly as an oscillator must be provided which
additionally must be energized. This problem is a large one,
particularly since this oscillator would have to be arranged within
the ball, but replacing batteries within the ball or recharging the
ball is problematic, if not impossible. In addition, this concept
of the tuned oscillator is also problematic, with regard to the
energy consumption, in that the oscillator must be kept switched on
irrespective of whether a rotation is detected, and will thus
consume as much valuable battery energy of the ball as in those
cases when no rotation is measured.
[0019] In addition, provision of an oscillator with a wide tuning
range is expensive and problematic particularly for low
frequencies, unless one resorts to digital circuits which, however,
require a lot more energy than analog circuits while being more
prone to defects. On the other hand, to build analog circuits with
oscillation characteristics at low frequencies, these circuits
would have to have either high capacitances or high inductances,
which in turn contributes to the sensor being expensive, to a large
volume required and, possibly, even to a heavy weight of the
sensor. In particular, however, volume, energy consumption and
especially also the weight of the sensor are measures which should
be kept as small as possible, since a ball without a sensor
actually must not differ, with regard to its properties for the
player, from a ball having a sensor.
SUMMARY OF THE INVENTION
[0020] It is the object of the present invention to provide an
efficient, low-cost but nevertheless flexible concept for measuring
a rotational frequency of a movable game device.
[0021] In accordance with a first aspect, the invention provides a
device for measuring a rotational frequency of a movable game
device using a high-frequency radio signal, the device including:
[0022] a provider for providing a time-varying radio antenna
receive signal; and [0023] a detector for detecting a low-frequency
frequency, which has been modulated onto the high-frequency radio
signal, using the time-varying radio antenna receive signal, [0024]
the low-frequency frequency of the time-varying radio antenna
receive signal representing the rotational frequency of the movable
game device.
[0025] In accordance with a second aspect, the invention provides a
method of measuring a rotational frequency of a movable game device
using a high-frequency radio signal, the method including the steps
of: [0026] providing a time-varying radio antenna receive signal;
and [0027] detecting a low-frequency frequency, which has been
modulated onto the high-frequency radio signal, using the
time-varying radio antenna receive signal, [0028] the low-frequency
frequency of the time-varying radio antenna receive signal
representing the rotational frequency of the movable game
device.
[0029] In accordance with a third aspect, the invention provides a
movable game device including: [0030] a radio antenna for providing
a time-varying radio antenna receive signal having a high-frequency
carrier portion and a low-frequency modulation portion; [0031] a
selector for extracting the low-frequency modulation portion; and
[0032] an interface for outputting the selected low-frequency
modulation portion.
[0033] In accordance with a fourth aspect, the invention provides a
computer program having a program code for performing the method of
measuring a rotational frequency of a movable game device using a
high-frequency radio signal, the method including the steps of:
[0034] providing a time-varying radio antenna receive signal; and
[0035] detecting a low-frequency frequency, which has been
modulated onto the high-frequency radio signal, using the
time-varying radio antenna receive signal, [0036] the low-frequency
frequency of the time-varying radio antenna receive signal
representing the rotational frequency of the movable game device,
when the program runs on a computer.
[0037] The present invention is based on the findings that one does
not resort to the natural magnetic field, which for various
locations on the earth deviates considerably and thus may cause the
sensitivity problems, but that one will resort to a radio hop, or
radio field, which does not naturally exist but is created by man
and exists, in sufficient intensity, wherever there is a need to
employ movable game devices. Radio fields which exist almost
everywhere are long-wave fields, medium-wave fields, short-wave
fields or ultrashort-wave fields. In every more or less developed
area, however, there are not only such broadcast fields, but also
higher-frequency fields which are even higher in energy, for
example mobile communication fields. High-frequency mobile
communication fields, just like broadcast and television fields,
have the property that they are radiated almost with circular
radiation characteristic and thus are available wherever the
rotation of movable game devices is to be measured. Depending on
the "carrier" field intended, different receive antennas may be
installed within the movable game device, all of which, however,
have the property that they have hardly any weight, are easy to
implement and are cheap, particularly due to the high level of
research/knowledge regarding radio antennas, and are even available
on the market in one-chip solutions together with a corresponding
front-end RF circuit. For lower frequencies, ferrite antennas may
be employed. For higher frequencies, dipole antennas may be
employed which are mounted, e.g., within the ball, e.g. on the
inside of the outer shell, or which are mounted within the ball
itself.
[0038] In accordance with the invention, one must simply evaluate
the field-strength variation of such an antenna in order to detect
the rotational frequency, since almost every antenna--whether one
likes it or not--has a directivity characteristic and will emit,
when it is rotated in an existing electromagnetic radio field, a
higher or lower field strength depending on the orientation of the
directivity characteristic of the antenna with the electromagnetic
field.
[0039] This field strength represents a variable which is easy to
measure and to process further, such as voltage or current at the
output of the antenna, whose envelope is to be detected in order to
obtain the frequency of the envelope, which is the same as the
rotational frequency of the game device. By resorting, in
accordance with the invention, to the radio field which exists
wherever movable game devices are to be measured with regard to the
rotational frequency, all problems associated with the magnetic
field in terms of volume, weight, sensitivity variations, etc., are
solved.
[0040] Antennas for detecting any wavelength ranges desired for
radio antennas exist in any sizes and may thus be adapted to the
size of the movable game device in any manner desired, since in
each wavelength range and, in particular, also in the
high-frequency wave range, at or above one GHz, there is typically
sufficient radio energy present on the basis of which the rotation
may be measured.
[0041] Even if no ambient field is present, the inventive detection
device may nevertheless operate in a reliable manner when, using
the game device which is typically always communicated with an
external transmitter via a radio interface, the external
transmitter is given the instruction to generate a radio field
whose modulation will then simply be measured by the very same
antenna of the movable game device with which the movable game
device communicates with the external device anyway. Thus, a
self-contained system may readily be implemented as an alternative
to the open radio system, while no high-energy steps are required
within the movable game device. Within a closed system, it is only
the external communication device that must transmit energy. When
this is done by a clock, or watch, or something similar, then the
battery in this clock will need replacing more often.
Alternatively, however, one may also take an energy supply line
fixedly installed, e.g., at a sports field, so that no battery
operation whatsoever will be required. Even if battery operation is
still necessary, a battery replacement and, in particular,
utilization of accumulators is considerably easier and less costly
than if a battery replacement within the ball would become
necessary, which is either not possible or may only be accomplished
at high expense and at the price of a downtime of the game device
if the characteristics of the game device are not to be greatly
influenced.
[0042] Preferably, the mobile game device further comprises a
shot-force measuring means based on the fact that a shot-force
measurement which is accurate, low in maintenance and, at the same
time, may be used in a flexible manner may be achieved in that a
time curve of an acceleration or a time curve of an internal
pressure of a movable game device is provided so as then to process
this time curve, specifically with the aim of obtaining a measure
of energy which depends on the energy transmitted to the object by
the shot. In addition, a means for providing information about the
force of the shot is provided which uses the synergy measure for
determining the force of the shot. Thus, what is performed is not
direct speed measurement but, in preferred embodiments, at the most
an indirect speed measurement, to the effect that a temporal
acceleration curve and a temporal pressure curve are detected, and
that is these time curves, or temporal curves, are processed to
obtain a measure of energy, that is some quantity which is somehow
connected to the energy in a linear or non-linear or in some other
manner. This measure is then used to provide force-of-shot
information. This force-of-shot information may be a quantitative
value which is, however, free from units, e.g. on a scale between 1
and 10, or it may be a value on an open-ended scale, or it may be a
value representing a force exerted on the movable game device at
the time of the shot, or it may be an energy value, i.e. a value of
the energy imparted on the movable game device at the shot.
[0043] Alternatively, the shot force may also be an indication of
length providing a measure of how far the ball would have flown,
for example, if the ball had been shot at an optimum angle and
without any rotation. Such a shot-force result is interesting, in
particular, for ball sports such as soccer or American football,
since to the players there, a measure of length, for example how
far a pass or kickout will have gone, means more than quantitative
values or physical force or energy units. However, for a comparison
with other players, the non-unit quantitative scale is highly
interesting, whether it is finite or open-ended.
[0044] In preferred embodiments, ball contacts are also detected.
Here, various components may be employed for both tasks. To this
end, the use of two signals having different signal speeds is ideal
to achieve a robust but nevertheless efficient and accurate
detection of a contact with a movable device. Thus, a detector
within the movable device, e.g. in a football, detects whether an
object, such as a player's leg, is located in the vicinity of the
football. This is effected, for example, by pressure, acceleration
or vibration measurement or by non-contact measurement.
[0045] Once a detection has been made to the effect that the object
is located in the vicinity of the movable device, the transmitter
module is controlled to transmit two signals having different
signal speeds. A receiver device connected to the object will
detect the first signal and then wait for a certain time period for
reception of the second signal having a lower signal speed. If the
signal having the lower signal speed is detected within the
predetermined time period which starts upon reception of the first,
fast signal, it shall be assumed that the object which has received
both the first and, within the predetermined time period, also the
second signal, was in contact with the movable device. This is
reflected in that a detector which has detected reception of the
second signal within the predetermined time period provides a
detector output signal, a memory subsequently storing the fact that
there has been a detector output signal, i.e. that it is very
likely for a ball contact to have occurred. Alternatively or in
addition, an absolute moment in time at which the detector signal
has occurred may be stored in the memory, so that when one thinks
of a football match, a sequence of moments result which may then,
e.g. after a match or during a match, be read out to ascertain, as
a function thereof, how many ball contacts a player had, or
generally speaking; how many contacts an object had with the
movable device.
[0046] If one assumes that, e.g., several football players are near
a ball, the fast signal will be detected by several receiver
devices. However, if the predetermined time duration is selected
such that it is very likely that really only that receiver device
which is located closest to the movable device can receive the
second signal within the predetermined time period, while receiver
devices which are more remote will also receive the second signal,
but only after the predetermined time duration has expired, no ball
contact will be registered for those players.
[0047] By setting the predetermined time duration in the receiver
devices worn, or carried, by the player, it is thus possible to set
the accuracy and/or the range to be detected. For this purpose, no
access to the ball itself is required.
[0048] In addition, the use of two signals of different speeds
allows to dispense with any complicated and, thus, failure-prone
electronics in the ball itself. One only needs to make sure that
the ball has a proximity detector which operates in a
contact-controlled or non-contact manner and which will then
control the transmission of the two signals of different delay
times. Thus, no complicated electronics are required within the
ball itself, which is a considerable advantage in particular since
the forces and accelerations acting on the ball may be huge, so
that there is a very rough environment for there to be an
electronic system within the ball.
[0049] On the receiver side, no personal identification or the like
is required, which is of considerable advantage--particularly if
one considers that what is dealt with here is a mass product, i.e.
that may players are to be provided with receiver devices--since
thus, all receiver devices may operate in an identical manner and
do not require any specific identification, which also renders the
receiver devices simple and low in or even completely free from
maintenance. In addition, a simple and robust structure also
ensures safety from tampering.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] These and other objects and features of the present
invention will become clear from the following description taken in
conjunction with the accompanying drawing, in which:
[0051] FIG. 1 is a schematic sketch of a pitch including a movable
device and several objects provided with receivers;
[0052] FIG. 2 depicts a player with a football as an example of a
movable device;
[0053] FIG. 3 is a schematic system sketch;
[0054] FIG. 4a is a more detailed view of the functional groups
within the movable device;
[0055] FIG. 4b is a more detailed representation of the transmitter
module of FIG. 4a;
[0056] FIG. 5a is a block diagram representation of the receiver
device; and
[0057] FIG. 5b is a more detailed representation of the receiver
device of FIG. 5a;
[0058] FIG. 6a depicts a qualitative schematic curve of the
acceleration over time during a shot;
[0059] FIG. 6b depicts a qualitative curve of the speed over time
during a shot;
[0060] FIG. 6c shows a qualitative curve of the force exerted on
the movable game device during a shot,
[0061] FIG. 6d shows a qualitative curve of the force as a function
of the distance covered, the force being exerted on a movable game
device during a shot;
[0062] FIG. 6e shows a preferred allocation table between the
energy measure and the force of the shot;
[0063] FIG. 7 shows a qualitative curve of the internal pressure of
a movable game device;
[0064] FIG. 8 shows a group of straight lines for determining the
shot force using the idle-state internal pressure as the
parameter;
[0065] FIG. 9 shows a schematic block diagram of the device for
measuring a force of shot exerted on a movable game device;
[0066] FIG. 10 shows a flow diagram for a preferred force-of-shot
measurement by means of a temporal pressure curve;
[0067] FIG. 11 shows a schematic block diagram of the inventive
concept for measuring a rotational frequency of a movable game
device;
[0068] FIG. 12a shows a spectrum of a radio-antenna receive signal
prior to selection;
[0069] FIG. 12b shows a spectrum of the radio-antenna receive
signal after the selection;
[0070] FIG. 13 is a schematic representation of the orientation of
two receive antennas with directivity characteristics which have
different directions of maximum sensitivity;
[0071] FIG. 14 depicts a scenario on a football pitch comprising
various transmitters, such as broadcast transmitters, mobile
telephones or other radio transmitters;
[0072] FIG. 15 is a flowchart of the communication within a
self-contained system; and
[0073] FIG. 16 is a block diagram of a preferred implementation of
the assembly within the mobile game device.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0074] To improve one's skills in a ball game or to be able to
compare oneself to other players, objective data must be obtained
in a simple manner. This data must be visualized such that a
training feedback or a comparison to other players is possible. To
this end, respective components are provided within the game
device, and, if need be, a data detection device including a
display unit is provided.
[0075] In a low-cost system, recognition of a person cannot be
effected via delay times of the radio signals. To this end, the
incoming radio signals would have to be compared to a highly
accurate time reference. Also, a network would have to be built
within which all times measured are compared to determine that
player who is closest to the ball. Therefore, one concludes, from
the transmission of a radio signal and an acoustic signal, as to
who had the last ball contact.
[0076] By measuring the forces acting on the game device, one may
also infer the shot force or the rotational speed of the game
device. If this entails an energy observation, the individual
player can learn to control his/her influence on the game
device.
[0077] Further advantages result from the further claims and
subclaims and from the following description.
[0078] Before the invention will be described in detail, it shall
be pointed out that it is not limited to the particular components
of the device or to the procedure discussed, since these components
and methods may vary. The expressions used here are merely intended
to describe particular embodiments, and are not used by way of
limitation. If the singular form or indefinite articles are used in
the description and in the claims, they also relate to the plural
form of these elements, unless the overall context clearly
indicates otherwise. The same applies in the opposite
direction.
[0079] FIG. 3 shows a schematic system sketch. In particular, it
shows a device for detecting the force and/or motion ratios on a
game device 7, such as a ball, an assembly 15 being provided in the
ball which is populated with several electronic components. Instead
of the assembly, the electronic components may also be disposed on
the ball's jacket, for example on the inside, or be suspended
within the center of the ball.
[0080] At least one of the following electronic components is
provided within the game device: [0081] a transmitter 4 for
acoustic or ultrasonic waves for transmitting an acoustic signal,
[0082] a pressure sensor 10, [0083] an acceleration sensor, [0084]
at least one Hall sensor 16, [0085] at least two magnetoresistive
sensors, [0086] at least two coils.
[0087] The electronic components are in connection with a receiver
2 via transmitter 4 for the acoustic or ultrasonic waves, or at
least via a radio transmitter 3, for example via radio 1, for
example to transfer the data detected by the electronic components.
In addition, a microcontroller 11 is provided for processing the
data. This data can then be transferred to a data detection device
12. An evaluation unit 13 is provided for evaluating the data
detected which is presented, if need be, on a display unit 14. Data
detection device 12 preferably is associated with at least one
player 6, preferably however with all players of a game to thereby
perform a localization, for example, of the nearest player, as will
be explained later on.
[0088] For some games, such as in a football match, it is often
interesting to know who had the most ball contacts. To determine
this, one must ascertain, during the ball contact, who has touched
the ball.
[0089] In a low-cost system, recognition of the person cannot be
performed via delay times of the radio signals. To this end, the
arriving radio signals would have to be compared with a highly
accurate time reference, and a network would have to be built
wherein all measured times are compared in order to determine that
player who is located closest to the ball. Alternatively, the field
strength of the transmitter at the ball could be used to estimate a
distance. However, this is imprecise.
[0090] To keep cost low, the delay time of sound. is measured
within the device. To this end, game device 7 emits, when
recognizing a force being exerted upon it, an acoustic signal as a
sound or ultrasound by a transmitter 4. At the same time, a radio
transmitter 3 transmits a radio signal. The receiver 2 of a data
detection device associated with player 6 registers the acoustic
signal and also the radio signal. The time difference yields the
distance from the ball. As soon as the radio signal is recognized,
the acoustic signal is awaited to arrive for 5 ms. If an acoustic
impulse is recognized within this time period, one may assume that
receiver 2 of the data detection device 12 associated with player 6
is spaced away from the ball by 1.5 meters at a maximum. It is then
very likely that this player has touched the ball. Preferably, each
player 6 carries, or wears, such a receiver. The number of acoustic
impulses recognized is counted and displayed. Using this
information and the hour of the event, one may then determine, in a
subsequent interplay of all data of all data detection units 12,
how many ball contacts a player 6 had. It is even possible to make
statistic statements about how successful passes were, since the
target of a pass may be determined by a time comparison. This may
be used to detect the following, for example: [0091] Who lost the
ball how many times to the opponent? [0092] Were the ball contacts
constant over the playing time and was there a drop in performance?
[0093] Who played how many passes to whom? [0094] How often did a
move pass several players of the same team?
[0095] The evaluation unit 13 thus has a means for evaluating
whether an acoustic signal of transmitter 4 for the ball or
ultrasonic waves arrives within a predetermined time period after
the arrival of the radio signal.
[0096] A device for measuring a shot force exerted on a movable
game device is depicted in FIG. 9. The device includes a means 90
for providing a time curve of an acceleration or an (internal)
pressure of a movable game device, the time curve occurring when
there is an impact on the game device caused by a shot.
[0097] Depending on the type of sport, the object acting upon the
movable game device is a tennis racket, a leg of a football player,
a hand of a handball player, a table tennis paddle, etc., if the
movable game device is a ball. Because of the fact that an object
acts upon the movable game device within the framework of a shot,
an acceleration is exerted upon the movable game device which--it
being assumed that the movable object was at rest before--was zero,
and which, at a time t.sub.0 at which the object hits the game
device, will suddenly increase and will decrease, as is shown in
FIG. 6a, until a time t.sub.1 at which the movable game device
leaves the object that has impacted the movable game device.
[0098] This drop at time t.sub.1 may be more or less abrupt, or the
case may occur where the acceleration curve a(t) relatively
"softly" approximates the value of zero, at which a constant speed
is achieved which will become negative at some point in time due to
the deceleration caused by air friction. The deceleration of the
movable game device due to friction or catching objects is
initially irrelevant to the force-of-shot measurement, or is to be
taken into account in dependence on the definition of the force of
the shot. The latter case will occur when, for example, a distance
over which a football would fly is indicated in meters as the force
of the shot. Then, the deceleration of the game device by air
friction would have to be taken into account, specifically it would
have to be taken into account on the basis of the energy measure
when calculating the information about the force of the shot.
[0099] Specifically, the device depicted in FIG. 9 includes a means
92 for processing the time curve of the acceleration or the time
curve of the internal pressure to obtain an energy measure which
depends on an energy imparted onto the object by the shot. This
energy measure may be, e.g., the speed at time t.sub.1 exerted upon
the movable game device by the shot. Such a situation is shown in
FIG. 6b. If it shall be assumed, again, that the object was at rest
at time t.sub.0, its speed will increase due to the acceleration
exerted at time t.sub.0, and will rise up until time t.sub.1. At
time t.sub.1, for example, the football leaves the football
player's leg, and a maximum speed v.sub.max is reached which will
then decrease again due to air friction. The instantaneous velocity
at time t between t.sub.0 and t.sub.1 may readily be currently
calculated by the equation shown on the right-hand side of FIG.
6b.
[0100] However, a preferred energy measure is the maximum speed at
time t.sub.1, since this energy--apart from a potential energy
which will typically be negligible--is the energy transferred by
the player onto the game device. If the player has transferred a
lot of energy, his/her force of shot is high. If, on the other
hand, the player has transferred little energy, his/her force of
shot was low, provided that for both cases other circumstances of
the game device, for example the internal pressure, are comparable,
as will be explained in detail later on with reference to FIG.
8.
[0101] Thus, means 92 may calculate, for example, the maximum speed
as an energy measure, or may even calculate, using the ball mass,
the energy associated with the maximum speed and referred to as
E.sub.max.
[0102] The device depicted in FIG. 9 further comprises a means 94
for providing information about the shot force on the basis of the
energy measure. The functionality of means 94 will be explained
with reference to FIG. 6e and may in this case be simply an
allocation table which maps the energy measure calculated to a
scale between, e.g., 1 and 10, as in the case of FIG. 6e, or to an
open-ended scale or to a tendency indication.
[0103] A tendency indication would consist in that a comparison of
the current energy measure with a previously determined energy
measure which was associated with another player is performed so as
to be able to state, as the tendency indication, i.e. as
information about the shot force, that the shot force of the
current player was larger, equal to or smaller than the shot force
of the previous player.
[0104] Mapping the energy measure to force-of-shot information in
such a manner may be conducted using any energy measures desired,
i.e. even in the event that the force as is depicted in FIG. 6c as
a curve over time is evaluated. Thus, the force curve is
proportional to the acceleration curve, to be precise with the mass
of the movable game device as the proportionality constant. The
curve of the force over time also provides an energy measure which
could be calculated, for example, by integrating the force over
time.
[0105] Alternatively, as is shown in FIG. 6d, the directional force
exerted on the ball may also be measured as a function of the locus
on which the ball moves during the shot. Thus, the force at the
location point .times.=0, at which the ball is located before it is
hit by the player's leg, will increase to a high value which will
fall down to a certain value. The ball leaves the player's foot at
the location point so on the locus, so that no more driving force
is exerted on the ball, but only deceleration forces which are
present due to the air friction and which, however, are not taken
into account in FIG. 6d.
[0106] Thus, an energy measure also represents the integration of
the force measured (acceleration) across the locus covered by the
ball. The locus may be measured, for example, at the same time with
the acceleration sensor within the ball if the acceleration sensor
is an acceleration sensor which operates in a three-dimensional
manner and is sensitive in terms of direction. Alternatively, the
locus of a projectile may also be calculated in different manners,
such as by using highly accurate satellite- or ground-based
positioning systems or by accessing predetermined tables. However,
micromechanical positioning systems using vibrating gyroscopes may
also be employed for determining the locus so as to be able to
numerically evaluate the integral depicted in FIG. 6.
[0107] However, the preferred embodiment of the present invention
is to provide a pressure sensor within the movable game device.
When the movable game device is shot, it could have a pressure
curve as is qualitatively depicted in FIG. 7. At a time t.sub.0,
the object hits the movable game device, which will lead to a
pressure increase in the movable game device, since the movable
game device is deformed by the object impacting the movable game
device. This pressure increase will then increase up to a maximum
pressure Pmax and will then decrease again so as to diminish again
down to the pressure at rest around time t.sub.1 which is
characterized in that the movable game device has no more contact
with the object.
[0108] It has thus been found out that the integral regarding the
pressure change, i.e. the area fill within the area shaded in FIG.
7, is connected to the energy exerted on the ball, so that the time
curve of the pressure may advantageously be employed for
determining the force of the shot.
[0109] The utilization of a pressure sensor is particularly
advantageous, compared to an acceleration sensor, since the
pressure sensor may be configured in a simple manner and to be
robust, in comparison with an acceleration sensor which, e.g., has
large masses of bending beams. In addition, it is inherent for a
pressure sensor not to emit a directional quantity, but to emit a
non-directional quantity if it is arranged within the movable game
device, which in acceleration sensors could only be achieved by
expensive provision of an acceleration sensor array which must be
sensitive in three spatial directions. On the other hand, one
single pressure sensor is sufficient to provide a pressure curve of
the internal pressure of the movable game device.
[0110] Thus, utilization of a pressure sensor provides a
maintenance-free, robust and, at the same time, low-cost
possibility of measuring the pressure curve within a movable game
device and of obtaining force-of-shot information, as will be set
forth later on with reference to FIGS. 8 and 10.
[0111] In a preferred embodiment of the present invention, the
pressure curve over time is integrated between t.sub.0 and t.sub.1,
specifically in accordance with the equation as is shown in FIG. 7.
This shows that what is integrated is not the absolute pressure
curve, but the curve of the pressure change in comparison to the
pressure at rest, p.sub.0. However, it would also be possible to
integrate the absolute pressure curve so as then to subtract area
97 following the integration. This results simply from the product
of time duration .DELTA.t and the pressure at rest.
[0112] As may be seen from FIG. 8, the shot force is highly
dependent on the level of the pressure at rest. This result from
FIG. 8 on the basis of the various parameter curves, one parameter
curve 97 being plotted for a small pressure at rest, p.sub.0,
whereas a different parameter curve is plotted for a high pressure
p.sub.0 at 98. In particular, the x axis of the group of curves of
FIG. 8 represents the integrated pressure change as a measure of
the energy., i.e.--calculated in physical units--a measure which
has (Pascal.times.seconds) as a unit. In illustrative terms, area
96 of the curve shown in FIG. 7 is plotted over the x axis. If one
assumes a ball having a small internal pressure, a force-of-shot
value will result along the straight line depending on how hard the
ball was hit, i.e. how high the shot force is. If, on the other
hand, a highly inflated ball is used for playing, a very much
higher force of shot has been obtained as a measure of the energy,
with the same integrated pressure change, in comparison with curve
97. This is due to the fact that a highly inflated ball is deformed
only to a small degree even by a very hard shot, whereas a ball
inflated to a very small degree is deformed by a relatively soft
shot already, the deformation corresponding to the integrated
pressure change.
[0113] Alternatively or in addition, the maximum pressure P.sub.max
of the pressure curve over time may also be determined by means 92
of FIG. 9. Specifically, one may assume, for simpler evaluations,
that the curve of the pressure over time, i.e. the manner in which
the shot impacts the object, is assumed to be roughly the same for
all shots, such that then solely the maximum value will be
decisive. In this case, a group of straight lines would be provided
which is similar to the group of curves in FIG. 8 but which would
not have, as the x axis, an integrated pressure change as the
measure of the energy, but the maximum pressure.
[0114] As another alternative, one could also determine the time
duration of the curve of the pressure deviation which, if typical
pressure curves are taken to be approximately the same with regard
to their shapes, is also a measure of the energy imparted on the
game device during the shot.
[0115] In a preferred embodiment of the present invention, the
internal pressure at rest p.sub.0 is initially determined in a step
100, as is depicted in FIG. 10. This determination may either occur
prior to or after the shot and is used to select one of the curves
in the group of curves of FIG. 8. In addition, the pressure change
is integrated over time in a step 102, specifically from time
t.sub.0 to time t.sub.1, using the temporal pressure curve p(t)
determined in a step 101. Thus, the integration regarding the
pressure change or regarding the pressure deviation from the
pressure at rest, set forth in step 102, provides the energy
measure which will then be used to determine a value on the
parameter curve selected. Preferably, the access made to a table
comprising a group of curves is conducted, in a step 103, such that
a three-dimensional table is given which comprises groups of three
values, a first value of the group of three being the pressure at
rest p.sub.0, a second value of the group of three being the
integrated pressure change, and a third value then being the shot
force as is plotted on the y axis of FIG. 8. This force-of-shot
information is provided by step 103. When comparing FIG. 9 and FIG.
10, it is obvious that steps 100 and 101 are performed by means 90,
that step 102 is performed by means 92, and that step 103 is
performed by means 94.
[0116] Depending on the implementation of the system, i.e. on the
diversity required, information about the type of game device which
is fed in at 104 may also be taken into account in step 103. For
example, the shot force may depend on whether the ball is a tennis
ball or a football. In addition, the shot force will vary from
brand to brand. This is relevant particularly when the "ideal
range" of the ball, which will then also depend on the surface of
the ball, is taken as the shot force. A smoother surface of the
ball has a smaller air resistance, so that with the same energy
transmitted, the shot force--measured in meters--will be higher
than that of a ball having a rougher surface. Nevertheless, both
force-of-shot results depend on the energy imparted on the ball,
and additionally depend on the type of game device fed in via line
104.
[0117] Depending on the implementation, all or only some of the
components shown in FIG. 9 will be arranged within the game device
itself or within a central device located at a distance from the
game device.
[0118] In the first embodiment of such a system, only an
acceleration sensor or a pressure sensor configured to store a time
curve of acceleration or pressure will be located within the game
device itself. This time curve of acceleration or pressure may then
be transferred, e.g. via a radio transmitter, to a receiver which
could be present with the player in the form of a watch, for
example. Alternatively, the ball need not necessarily have a radio
sensor but may have an output interface which, when the ball is
placed into a specifically configured docking station, will read
out the stored curves of acceleration or pressure. Then, the
processing in block 92 and the provision of force-of-shot
information in block 94 would take place in an external station,
such as the player's watch or in a central receiving station on a
football pitch, etc.
[0119] Alternatively, both the functionality of means 90 and means
92 may be integrated into the ball, and the ball already supplies
the energy measure to an external receiving station. This results
in that less data must be transferred from the ball to the outside,
but that more processor power is required within the game
device.
[0120] Alternatively, all means 90, 92, 94 may be implemented
within the mobile game device, so that only the information about
the shot force is indicated by the ball even in a direct manner, or
is output via an output interface which may be, e.g., a radio
interface or a contact interface.
[0121] The system depicted in FIG. 9 also includes the
functionality of the external receive interface 6 if only one
sensor is present within the ball and if the ball outputs the time
curve of the acceleration or internal pressure. Then, means 90 for
providing a time curve of acceleration or internal pressure of FIG.
9 is an input interface of the external calculator which
additionally also comprises means 92 and means 94.
[0122] For example, the device for measuring the shot force may be
arranged and implemented fully within the mobile game device or
fully outside the game device or partly within and partly outside
the mobile game device.
[0123] In this sense, the method for measuring a force of shot
exerted on the movable game device in such a partial implementation
both includes the game device and the evaluation device or only the
game device or only the evaluation device.
[0124] The game device thus provides detection of the shot force
and the flying speed of a game device 7 which may be determined
therefrom. Thus, in a football game there is often the question of
who has the "hardest" shot. In particular for this embodiment, but
also for the other embodiments there is the possibility of
integrating the evaluation unit 13 also into the assembly 15 within
the game device 7. A sensor measuring the shot force may be mounted
in game device 7. This sensor is preferably a pressure sensor 10 or
an acceleration sensor. The information of this sensor is measured
by an internal microcontroller and transferred, for example, to
display unit 14 on data detection device 12 of the player. For
determining the shot force, it is necessary to measure the energy
the ball has been imparted during the shot. To this end, the
evaluation unit 13 has means for detecting the pressure, determined
by pressure sensor 10, over time or for detecting the acceleration
detected by the acceleration sensor. In addition, provision is made
for calculating means for calculating the force applied to ball 7
on the part of player 6 using the pressure curve or acceleration
curve.
[0125] With the acceleration sensor, the acceleration is measured
directly and reported to the microcontroller within game device 7.
Said microcontroller calculates the force that has acted upon the
ball from the known mass of the ball and the acceleration measured.
These calculations also include the aerodynamics and the time curve
of the energy transferred to the ball. The calculation comprises
not only transferring the overall energy to the evaluation unit 13,
but also comprises transferring the time curve of the energy
transferral to the ball.
[0126] In the alternative use of a pressure sensor 10, one measures
how the internal pressure of the ball increases during a shot.
These pressure changes and the associated time curve allow the
microcontroller within the ball to determine the force that has
been exerted on the ball. Using the pressure measurement, it is
possible to ascertain how much the ball was deformed. The higher
the level of deformation, the larger the shot force. To this end,
the peak value and the pressure curve of the internal pressure are
measured using pressure sensor 10. Using a group of curves, the
energy supplied to the ball is measured. For example, the group of
curves may be determined in advance in a empirical manner, by means
of a shooting system and is different for each type of ball.
[0127] Then the shot force may be determined in very accurately
from the energy transferred and the time curve. Beside the shot
force, the overall energy may also be displayed. This allows to
obtain information about the type of shot. Thus, the ball may be
played with much more precision on an even energy supply. Thus, if
the duration of the energy supply is displayed additionally, for
which purpose additional detection means may be provided, this may
also be trained.
[0128] The energy may be used to infer the flying speed the ball
has obtained. To this end, the weight and aerodynamics of the ball
are taken into account. The flying speed determined is the value
that is reached when the ball may fly off freely after the shot. In
addition to the action of force, the time of the ball being hit,
and the time of the ball touching down may also be determined using
pressure sensor 10 and/or the acceleration sensor. By means of the
force information and the time duration of the flight, it is quite
readily possible to calculate the distance the ball must have
flown.
[0129] In addition to the above implementations of ball contact
detection or of shot force measuring, or as an alternative to these
concepts, the inventive rotation measurement concept is implemented
which, if it is implemented on its own, requires all of the
components described below, but which, if it is implemented in
addition to the other aspects of contact measuring and shot force
measuring, advantageously resorts to the already existing
components, such as the radio interface or a small. programmable
processor within the ball and/or the entire RF front end of the
ball.
[0130] The device for measuring a rotational frequency of a movable
game device using a high-frequency radio signal initially includes
a means 120 for providing a time-varying radio antenna receive
signal. Means 120 may then, if it is implemented within the game
device, include one or several antennas which may be configured for
certain reception frequency ranges. However, if the device shown in
FIG. 12 is fully integrated externally within a monitoring device,
such as a clock, or watch, means 120 for providing the radio
antenna receive signal is configured as a radio input interface of
the clock, or watch, i.e. of the remote communication device not
integrated into the ball.
[0131] Depending on the implementation, the radio antenna receive
signal is a signal having an exemplary spectrum as in FIG. 12a
prior to the selection. Alternatively, the radio antenna receive
signal is already a baseband signal after a selection, as is
depicted in FIG. 12b. If the device in accordance with FIG. 11 is
configured within the mobile game device, the means for providing
the radio antenna receive signal will be implemented as an antenna
providing the spectrum of FIG. 12a, a means 122 connected
downstream for detecting a comparatively low-frequency frequency
which has been modulated onto the high-frequency radio signal
initially conducting the selection to obtain the spectrum of FIG.
12b and to then determine the frequency of the dominant component
of this spectrum.
[0132] If, on the other hand, the radio antenna receive signal is
already a selected signal having a spectrum in accordance with FIG.
12b, means 122 for detecting the comparatively low-frequency
frequency which has been modulated onto the high-frequency radio
signal will already obtain the low-frequency frequency, and now
only has to measure the value of this frequency to provide a
rotational-frequency indication on the output side.
[0133] A spectrum of the radio antenna receive signal prior to
selection is shown, by way of example, in FIG. 12a, the transmitter
frequency, i.e. the carrier frequency of a broadcast transmitter,
television transmitter or mobile communication transmitter being
designated by f.sub.transmitter. The two bands of an amplitude
modulation resulting from a rotation of the mobile game device in
the field are also shown, the value of .DELTA.f, i.e. the distance
of the two sidebands from the carrier frequency, being identical
with the rotational frequency.
[0134] If the radio field "exploited" for rotation detection. has
itself a modulation in the range of the rotational frequency, the
modulation will superimpose onto this modulation, which is already
radio-inherent, due to the rotational frequency. Due to the fact
that typical dipole antennas have, e.g., intense directivity
characteristics, the modulation will be very high due to the
rotation, so that actually, clear sidebands will always be
detectable. If, however, this is not the case on one occasion, one
may readily resort to any other transmitter that is currently
active in the entire spectrum of radio frequencies and does not
have such a radio-inherent low-frequency modulation. Thus, it is
extremely unlikely that not even one single sender should be
available that does not have such a low-frequency modulation. In
this case, however, the inventive concept could still activate the
closed system function, as will be explained with reference to FIG.
15.
[0135] The radio antenna receive signal after the selection is
shown in FIG. 12b. It may be generated in various manners, such as
by downmixing the spectrum of FIG. 12a. However, detection is
simpler when a simple envelope detection is performed or when one
resorts to typical broadcast receivers such as, e.g., a ratio
detector. The simplest manner of selection, however, is to perform
an envelope detection using a peak-value detector to extract the
low-frequency modulation component. FIG. 12b, for example, depicts
a radio antenna receive signal after the selection which now
includes only a low-frequency modulation oscillation, the frequency
of which may be detected in various manners by means 122 for
detecting. For example, means 122 may be configured to perform an
extreme-value detection in the time signal after the selection, for
example to determine two adjacent maxima, two adjacent minima or an
adjacent maximum and an adjacent minimum and to calculate therefrom
the temporal distance associated with the rotational frequency. In
case two adjacent maxima or two adjacent minima are detected, the
rotational frequency equals the reciprocal of the time duration
expired between two adjacent maxima or minima. In case one maximum
and one minimum are detected, the rotational frequency equals the
reciprocal of double the time that has passed. In case two adjacent
zero crossings of the low-frequency time signal are detected, the
rotational frequency equals the reciprocal of double the time
period that lies between two adjacent zero crossings.
[0136] When there is a highly directional field, it may be possible
for the ball to rotate in such a manner with regard to the field
that no, or only a very weak, modulation of a certain transmitter
is detected. In this case, it is preferred to employ two antennas
whose directions of maximum sensitivity diverge by 90 degrees, as
is depicted in FIG. 13. A first antenna 130a has a schematic
directivity characteristic as is shown at 132a. A second antenna
130b has a directivity characteristic as is shown at 132b in FIG.
13. Both antennas have directions of maximum sensitivity, as are
drawn in at 134a and 134b, respectively. Since both directions have
an angle of 90.degree. toward one another, one of the two antenna
signals will in any case have a higher modulation than the other
antenna signal. When contemplating FIG. 16, which depicts a
preferred implementation of the assembly within the mobile game
device, a selection of the two antenna receive signals in two
selector elements which may be configured, for example, as envelope
detectors 160a and 160b is now conducted, the selected
low-frequency signal portions then being examined within a control
162 to select the better signal for a transmission via a downstream
RF front end 164 and the subsequent transmission via RF antenna
166. Alternatively, control 162 may also be configured to add both
selector output signals. Alternatively, an advantage may also be
rendered by performing an addition on the RF side, so that only one
single selector is required which subjects the added antenna
signals to a selection. Still further alternatives are to transmit
both RF antenna signals from the ball to the evaluation device
either prior to or after the selection, all signal processing
taking place in the evaluation device when the RF signals are
transmitted from the ball to the evaluation device. The individual
implementation will depend on other boundary conditions, such as
the availability of electrical current within the game device, as
few radio signals as possible being transmitted if the battery
requirements are particularly large, since transmitting requires a
considerable proportion of the energy required for overall
processing. However, if the requirements placed upon the energy
consumption of the game device are not quite as large, the game
device will transmit, in specific implementations; both or only one
RF signal or both or only one LF signal to the evaluation station,
since still other evaluations may be performed using this
information, such as aerodynamic calculations, velocity
calculations, etc.
[0137] FIG. 14 shows an overall scenario comprising three different
transmitters S1, S2, S3, all having such antennas that they have
circular radiation characteristic, which is particularly true if
the transmitters are television transmitters, radio transmitters or
generally speaking broadcast transmitters or if the transmitters
are mobile phone base stations or even individual mobile phones
which are typically present in large numbers in a football stadium,
which is schematically depicted at 140 in FIG. 14.
[0138] Also, in FIG. 14 a mobile game device 142 is drawn, by way
of example, as a football, the antenna direction maxima 134a, 134b,
as have been set forth with reference to FIG. 13, having also been
drawn in. In addition, an evaluation device 144 is drawn which is
either located outside the pitch, as shown in FIG. 14, e.g.
stationary or carried, or worn, by a person, or which may
alternatively be configured as a watch worn by a user on his/her
wrist.
[0139] Typically, the transmitters will be arranged at different
heights and have different transmit characteristics, so that it is
very likely that already one single antenna arranged within ball
142 will provide a radio antenna receive signal, due to a rotation
of the ball, prior to the selection or after the selection, which
has a significant LF amplitude due to the rotation of the ball.
Typically, these LF amplitudes will be below 100 Hz if footballs
are contemplated. However, other applications exist wherein the
rotations can be higher or lower. Depending on the ball equipped
with the invention, one may thus search for other low-frequency
components.
[0140] So far, the present invention has been described by means of
an open system, wherein one resorts to external radio fields, the
presence of which, in accordance with the present invention, is not
interpreted as "electrosmog" or the like, but as a detection field
advantageously exploited for measuring rotational frequency.
[0141] Alternatively or additionally, the present invention may
also be operated as a closed system, which is to be implemented
with the smallest of effort particularly if the ball has a radio
interface comprising an RF front end and an antenna anyhow, as is
the case with preferred embodiments. Then the ball, for example
when it finds that no reasonable radio field exists, or simply upon
the demand of a user or when no additional receive antennas are
provided, may send a radiation command to the remote evaluation
device 150. The remote evaluation unit will then typically send an
unmodulated radio signal because of the radiation instruction by
the evaluation unit, as is shown at 152. Thereupon, the mobile game
device measures a time variation of the received field strength.
Alternatively, this measurement may also take place without the
evaluation device so as to achieve a measurement in accordance with
step 154. Finally, the mobile game device sends information
indicating the rotational frequency of the mobile game device to
the evaluation device, as is depicted at 156. It is then left to
the evaluation device to output the rotational frequency, as is
shown at 158 in FIG. 15.
[0142] The rotation information may be used for training so-called
"curling crosses" in football. To this end, it is important for the
user to immediately get a feedback about his/her shot. For this
purpose, the rotational speed within the ball is measured and
transmitted via radio 1 to the player's data detection device 12.
The components are to be arranged such that during their movement
when the game device 7 is rotating in a radio energy field, a
modulation frequency determinable by the evaluation unit 13 will
result which can be converted into the rotational speed.
[0143] Thus, the sensor measures the radio field and determines the
field strength. When the ball rotates, the field strength undergoes
a modulation. The frequency of the modulation is directly
proportional to the rotational speed of the ball. During the
measurement of the radio field, the directional vector of the radio
field is determined. The rotation of this vector is proportional to
the rotation of the ball. For the purposes of measuring the
rotation, neither a linearity of the measurement nor a
determination of the direction of the field is required. When the
ball rotates, the input voltage has an alternating voltage
superimposed on it, the frequency of which is the rotational
frequency of the ball. The frequency of this alternating voltage is
the rotational frequency of the ball. Evaluation of this voltage
may either be performed discretely via an analog circuit or using a
microcontroller. To obtain a signal that can be evaluated for each
possible axis of rotation of the ball, two receive antennas offset
by 90.degree. are used, as has been set forth.
[0144] In accordance with the invention, radio transmitters are
thus used which in an open system are typically existing radio
transmitters, and in a closed system are created by the evaluation
unit itself.
[0145] To determine the rotational speed, radio transmitters may
also be used. In this case, the change of the field strength of any
radio transmitter, for example a medium-wave transmitter, is used.
The frequency of the change in field strength is proportional to
the rotational frequency. Beside a dipole, a coil or a ferrite
antenna may be used as an antenna. Since there are enough active
long-, medium-, and short-wave transmitters in each country, there
is no need in the system to operate one's own transmitters. If
transmitters having a relatively high frequency are to be used as
the reference, a dipole antenna is a possibility, which dipole
antenna may be deposited, for example, on the ball's electronic
system or even on the ball's envelope in the form of conductive
traces. A frame antenna is suitable for low frequencies. It may be
deposited as a coil in the form of conductive traces for assembly
15 of the ball's electronic system. A ferrite antenna is suitable
for low frequencies. It may be constructed to be very small and
will nevertheless generate a relatively large output signal. With
all antennas it is necessary for two receive directions to be built
up, so that a signal can be measured at any axis of rotation. The
only thing that is important with signal measurement is the field
strength. For this purpose, an amplifier having a high level of
dynamics is necessary. The amplification should be logarithmic, for
example, so that the A/D converter of the microcontroller need not
be too wide.
[0146] An extremely low-power microcontroller takes on the data and
the control of the ball's electronic system. Said microcontroller
is woken up at the start of the game. If the microcontroller has
not observed any game for a relatively long period, it will
automatically switch off. The main task of microcontroller 11,
which may be integrated in the data detection device in the game
device as well as, or in addition to, microcontroller 11, is to
process the data such that it can be transmitted via radio 1 with
as little energy as possible. The data is preferably transmitted
several times via radio, e.g. via a 2.4 GHz radio link, so as to be
able to correct any errors.
[0147] Current supply may be realized in two known ways. On the one
hand, one may use an accumulator, which, however, requires charging
equipment. On the other hand, one may use a primary battery 21
within the data detection device and a primary battery 22 within
game device 7, it not being possible, however, for the latter to be
replaced within the ball.
[0148] In the accumulator version, a charging coil is mounted
within the ball, using which the accumulator may be loaded in an
inductive manner. With the version including battery 22, the ball
is supplied using lithium batteries. The capacitance is designed
such that the functionality of the electronic system is ensured for
1000 hours. With an average playing time of 1 hour per day, the
battery would last for three years.
[0149] Within data detection device 12, a transceiver is integrated
as a receive unit 2. Said transceiver receives the data from the
ball and/or can establish a connection to other data detection
devices in order to exchange data. Transmission and reception of
data takes place, e.g., within the 2.4 GHz band.
[0150] The transceiver may receive and transmit data. Thus, it is
possible to couple the data detection devices to one another.
Thereby, the ball contacts can be transmitted to the other data
detection devices during the game, so that a very accurate
statistical set of data will be created in the network so as to be
able to judge the game. If need be, it is also possible, by means
of the data transmission, to facilitate small computer games in
which the users may play in a networked manner.
[0151] The data within data detection device 12 is processed using
a relatively large microcontroller 11. This microcontroller is
extremely low in its power consumption. The data is exchanged via
the transceiver and visualized on a display unit 14.
[0152] The data processed is displayed using a graphic display. The
display has an integrated controller, to which the microcontroller
is connected. Operation is effected via several keys 20, the
function of which is dynamic.
[0153] The current supply of data detection device 12 must be
highly power-saving. Battery 21 may be replaced. Microcontroller 11
and the display are extremely power-saving. Data transmission is
designed such that the transceiver is in operation only for a very
short time in each case.
[0154] With the ball version including an accumulator, a charging
station is necessary. Since there is no line connection to the
ball's electronic system, it is necessary to inductively charge the
ball in a known manner. To this end, the charging station comprises
a transmitter coil with which the energy is transferred into the
ball.
[0155] In order to be able to communicate with other evaluation
units, it is necessary to convert the radio communication to a
different protocol. Since it is with a probability of 99 % that a
common PC will be used, a conversion in accordance with, e.g., USB
is envisaged.
[0156] A more detailed description will be given below of the
interacting components of the preferred concept, i.e. of the
movable device of FIG. 4a and FIG. 4b, and of the receiver device
of FIGS. 5a and 5b. Movable device 7 contains a detector 23 which
may be, e.g., the pressure sensor 10 of FIG. 3 and which detects if
ball 7 is touched. However, detector 23 may include a contactless
sensor which operates in an electric, acoustic, optical or
electromagnetic manner and detects, for example, whether a magnetic
or electric field of any kind which is generated, e.g., by a
respective transmitter within a football player's shoe approaches
the ball. Detector 23 is configured to detect that an object, i.e.,
for example, a leg, a foot, a shoe, a racket, a bat, or the like,
is positioned in the vicinity of or at the game device.
[0157] In addition, mobile device 7 includes a transmitter module
24 configured to transmit a first signal having a first signal
speed, and to further transmit a second signal having a second
signal speed which is smaller than the first signal speed. The
transmitter module is configured to transmit the first and second
signals in response to a detector output signal, as is shown by
signal arrow 25 in FIG. 4a.
[0158] As has already been set forth, detector 23 is a touch sensor
configured to detect the movable device being touched by the
object. Such a touch sensor is, for example, the pressure sensor,
however, it is also an acceleration sensor or any other sensor
detecting whether the object engages with the surface of game
device 7. Alternatively, the detector may also be configured as a
contactless sensor which, as has been set forth, detects in some
way that there is an object in the vicinity of the movable device.
A contactless sensor which detects whether an object is located at
a predetermined distance, which is smaller than or equal to 10 cm,
from the movable device is suitable for specific embodiments. Then
it is very likely for the object to actually touch the movable
device, since the only aim is to cause the object to touch the
movable device, for example when one thinks of a football as the
movable device, or of a tennis ball. One may assume, with a
probability of almost one hundred percent, that once the object is
located within the predetermined distance, the object will
eventually have contact with the movable device.
[0159] The transmitter module is configured to send two signals
having different signal speeds. Preferably, a radio signal
generated by radio transmitter 3 is used as the first, fast signal.
The second signal is generated by a sound transmitter 26 preferably
configured as an ultrasonic transmitter. Both transmitters are
controlled by the detector signal supplied via line 25, so as to
send both signals at the same time or essentially at the same time,
i.e. within a period of, e.g., 1 to 2 ms, in response to the
detector signal. Alternatively, however, the transmitters may be
configured such that the radio transmitter sends the first signal
at a specific moment determined by detector signal 25, and that the
ultrasonic transmitter then waits for a predetermined time duration
before the ultrasonic signal is transmitted. Here, the reception of
the radio transmitter would also not immediately cause a
chronometer to be activated on the receiver side, but the
chronometer would be activated within a predefined time duration
upon reception of the first signal, i.e. not immediately upon
reception of the first signal, but depending on the reception of
the first signal.
[0160] Alternatively, ball-contact detection could also be used to
initially send the ultrasonic signal and then, after a specific
time duration, the radio signal which will then overtake the
ultrasonic signal, as it were, so that on the receiver side, a very
short predetermined time duration is sufficient, within which the
radio signal and the ultrasonic signal will arrive. However, it is
preferred that both transmitters send their signals at the same
time and that an accordingly longer predetermined time duration be
employed on the receiver side, and/or that on the receiver side,
the chronometer be started immediately upon reception of the radio
transmitter.
[0161] The predetermined time duration depends on the difference of
the speeds of the first, fast signal and the second, slow signal.
The smaller this difference in speeds, the smaller the
predetermined time duration that may be selected. The larger the
difference in speeds, the longer the predetermined time duration
that must be set. In addition, the predetermined time duration
depends on whether the first and second signals are really sent at
the same time, or whether the first and second signals are sent
with an offset in time, a delay in the second signal with regard to
the first signals leading to a delay in the start of the
predetermined time duration, while a delay of the first signal
relative to the second signal leads to a smaller predetermined time
duration. In general, however, predetermined time durations of less
than 5 ms are preferred, as has already been set forth.
[0162] As is depicted in FIG. 5b, on the receiver side, the
receiver module is in connection with a detector 28 which may be
coupled to a memory 29 or which may be coupled to a further radio
transmitter within the receiver device, which is not shown in FIG.
5a, however. The detector and memory 29 are preferably contained
within evaluation unit 13 of FIG. 3. The receiver device overall
shown at the bottom of FIG. 3, or the receiver device shown in FIG.
5a, is preferably configured such that it is integrated into a
watch, or has the shape and looks of a watch, so that it may
readily be worn by, e.g., a football player or a tennis player
without said player being adversely affected in practicing his/her
sport. Generally speaking, the receiver device is mountable to the
object whose vicinity to the mobile device is detected by detector
23 in FIG. 4a, and comprises an appropriate fixing device which is
not shown in FIG. 5a but which has the shape, for example, of a
watchstrap, a fixture for a watchstrap, a clip or a different
mounting device which may be secured in some way to the object
and/or to a player.
[0163] The receiver module 2 is configured to receive the first
signal having the first signal speed and the second signal having
the second signal speed, which is smaller than the first signal
speed. In addition, detector 28 is configured to provide a detector
signal indicating whether the second signal has been received
within a predetermined time duration since reception of the first
signal. In addition, the detector is preferably coupled to memory
29 which is configured to store the moment when the detector
provides the detector signal. Alternatively, a further transmitter
may be present instead of the memory, the transmitter being
configured to send the detector signal to a central detection point
where, e.g., an online evaluation of ball contacts for the
individual players is performed.
[0164] Such an online detection point would be, for example, a
receiver arranged somewhere in the vicinity of a football pitch. In
this case, any receiver device would send, on the output side, a
contact with the movable device together with an identification for
the player wearing the receiver device, so that indisputable
statistical data can be obtained as to which player had how many
ball contacts.
[0165] Recently, one has found that such information about ball
contacts etc. are increasingly detected, shown and provided to a
large audience and/or the commentator, for example, in football
matches, so as to increase the information content for the
viewers.
[0166] In the implementation with memory 29, for example, no
central receiver device is required on the football pitch. Instead,
the memory may be evaluated, for example, at half-time or at the
end of the game, or in a contactless manner during the game without
any interaction on the part of any player, so as to either obtain a
count value for each player indicating how often the player had
contact with the movable device. In this case, player 29 would be
implemented as a counter incremented by 1 during each detection of
the detector signal. Alternatively or in addition, the memory may
also detect an absolute time of a clock, or watch, preferably
contained within the receiver device and depicted at 30 in FIG. 5b.
Then the memory would store a sequence of moments in time which may
then be evaluated to be able to establish, for each player, a
"ball-contact profile" over time. Here, it may also be possible to
subsequently correct any erroneous detections that may have taken
place, for example if one found out that more than two players had
contact with the ball at the same time. Simultaneous contact of two
players is relatively likely, for example when one thinks of a
"50/50 ball". However, a contact of, e.g., three players with the
ball at the same time, becomes very unlikely in football. However,
in tennis, for example, a contact of two tennis rackets at the same
time is already impossible, so that here, additional information
about typical situations, in a sport, involving the movable game
device may be used to perform an evaluation wherein errors may be
eliminated.
[0167] FIG. 5b shows a more specific embodiment of the receiver
shown in FIG. 5a. The receiver module comprises, on the one hand, a
radio receiver 32 for receiving the first, fast signal, and an
ultrasonic receiver 32 for receiving the second, slower signal.
Radio receivers and ultrasonic receivers may also be configured
differently, as long as they receive any signals having different
signal speeds. Depending on a radio signal received, a detector 28
activates a chronometer 31 via a start line 35. Once a
predetermined time duration and/or the predetermined time period
has expired, the chronometer is stopped, which will typically be
performed such that the chronometer 31, which is set to the
predetermined time period, will provide a stop signal to the
detector via a stop line 36.
[0168] If the detector detects an ultrasonic signal upon receiving
the stop signal, no detector signal will be output on a line 37. In
this case, it is actually assumed that the receiver device is
located at such a long distance from the movable device that it is
very likely for the movable device to not have been hit. However,
if an ultrasonic signal is received by the detector before
receiving the stop signal, i.e. before the predetermined time
period has expired, the detector signal 37 will be output, which
will then be stored by the memory, the memory being, for example, a
counter incremented by 1 by the detector signal.
[0169] Alternatively, the detector signal is supplied to a clock,
or watch, which performs absolute time measurement, which, e.g.,
may be an actual absolute time of the day, but which, e.g., is also
an absolute time which begins, e.g., at the beginning of the game
and is thus not directly an absolute time, but renders one minute
of, e.g., a football game. At the time of the detector signal,
clock 30 will then provide its current reading via a data line 38,
so that the memory is then able to store this specific moment in
time. A random evaluation of the players' activity may be performed
by means of an evaluation unit having an interface, as may be
implemented, for example, by display unit 14 in FIG. 3 or in FIG.
5b, which cooperates, in particular, with microcontroller 11 of
FIG. 3.
[0170] Depending on the circumstances, the inventive methods may be
implemented in hardware or in software. The implementation may be
on a digital storage medium, in particular a disk or a CD with
electronically readable control signals which may cooperate with a
programmable computer system in such a manner that the respective
method is performed. Generally, the invention thus also consists in
a computer program product having a program code, stored on a
machine-readable carrier, for performing the inventive method, when
the computer program product runs on a computer. In other words,
the present invention is thus also a computer program having a
program code for performing the method of converting, when the
computer program runs on a computer.
[0171] While this invention has been described in terms of several
preferred embodiments, there are alterations, permutations, and
equivalents which fall within the scope of this invention. It
should also be noted that there are many alternative ways of
implementing the methods and compositions of the present invention.
It is therefore intended that the following appended claims be
interpreted as including all such alterations, permutations, and
equivalents as fall within the true-spirit and scope of the present
invention.
* * * * *