U.S. patent application number 12/943831 was filed with the patent office on 2011-11-17 for method of sensing the proximity of a human.
Invention is credited to Thomas Chan.
Application Number | 20110281492 12/943831 |
Document ID | / |
Family ID | 34949580 |
Filed Date | 2011-11-17 |
United States Patent
Application |
20110281492 |
Kind Code |
A1 |
Chan; Thomas |
November 17, 2011 |
Method of Sensing the Proximity of a Human
Abstract
A toy including at least one capacitive sensor comprising a
metal plate constituting one of the two plates of a capacitor, the
second plate being constituted by a portion of a living being in
the proximity of the toy, at least one effects generator; and a
control circuit including means for causing effects to take place
in response to stimulation of said capacitive sensor; the toy being
characterized in that said metal plate of said at least one
capacitive sensor is used as an antenna for picking up radio
frequency transmission from said portion of a living being in the
proximity of the toy.
Inventors: |
Chan; Thomas; (Hong Kong,
HK) |
Family ID: |
34949580 |
Appl. No.: |
12/943831 |
Filed: |
November 10, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11571789 |
Jan 21, 2008 |
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PCT/EP05/08208 |
Jan 21, 2008 |
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12943831 |
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Current U.S.
Class: |
446/297 |
Current CPC
Class: |
A63H 2200/00 20130101;
H03K 2217/960715 20130101; H03K 17/955 20130101; A63H 3/00
20130101 |
Class at
Publication: |
446/297 |
International
Class: |
A63H 3/28 20060101
A63H003/28 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 8, 2004 |
FR |
04/07655 |
Claims
1. A method of detecting the presence of a human being proximate to
a doll, the doll having a capacitive sensor including an RC
circuit, the method comprising the steps of: charging the RC
circuit; starting a counter to measure the discharge time of the RC
circuit; storing a value of the discharge time in a memory by a
processor; repeating the steps of charging, starting, and storing
until a plurality of discharge time values are stored by the
processor; and analyzing the plurality of discharge time values to
determine whether a human being is proximate to the doll.
2. The method of claim 1, wherein the RC circuit includes a
resistor and a capacitor, and the charging the RC circuit includes
charging the capacitor.
3. The method of claim 1, wherein the doll includes an amplifier,
and the charging the RC circuit includes the amplifier charging the
capacitor.
4. The method of claim 1, wherein the steps of charging, starting,
and storing are repeated until the plurality of discharge time
values includes ten discharge time values.
5. The method of claim 1, wherein the RC circuit includes a
capacitor and the discharge time corresponds to the time the
capacitor takes to discharge.
6. The method of claim 1, wherein the plurality of discharge time
values is a first plurality of discharge time values, the analyzing
the plurality of discharge time values includes comparing a mean
value of the first plurality of discharge time values to a
reference value associated with no human being present.
7. The method of claim 6, wherein the analyzing the plurality of
discharge time values includes comparing the mean value of the
first plurality of discharge time values to a mean value of a prior
plurality of discharge time values in the event that the mean value
of the first plurality of discharge time values is different from
the reference value.
8. The method of claim 7, wherein the analyzing the plurality of
discharge time values includes comparing variations around a mean
value of the plurality of discharge time values to a sinusoidal
waveform.
9. The method of claim 8, wherein the analyzing the plurality of
discharge time values includes determining that a human being is
proximate to the doll if the variations match the sinusoidal
waveform.
10. The method of claim 9, wherein the doll includes an effects
generator that is activated if the variations match the sinusoidal
waveform.
11. A method of detecting the presence of a human being proximate
to a doll, the doll having a capacitive sensor including an RC
circuit, the method comprising the steps of: charging a capacitor
in the RC circuit; starting a counter to measure the discharge time
of the capacitor; storing a value of the discharge time in a memory
by a processor; repeating the steps of charging, starting, and
storing until a first plurality of discharge time values are stored
by the processor; and comparing the first plurality of discharge
time values to a second plurality of discharge time values to
determine whether a human being is proximate to the doll.
12. The method of claim 11, wherein the doll includes an amplifier,
and the charging a capacitor includes the amplifier charging the
capacitor.
13. The method of claim 11, wherein the discharge time value
corresponds to the amount of time the capacitor takes to
discharge.
14. The method of claim 11, further comprising the step of:
comparing the first plurality of discharge time values to a
reference value.
15. The method of claim 14, wherein the reference value is
associated with no human being proximate to the doll.
16. The method of claim 11, wherein the comparing the first
plurality of discharge time values to the second plurality of
discharge time values includes comparing a mean value of the first
plurality of discharge time values to a mean value of the second
plurality of discharge time values.
17. The method of claim 11, further comprising the step of:
comparing variations in the first plurality of discharge time
values around the mean value of the first plurality of discharge
time values to a sinusoidal waveform.
18. The method of claim 17, wherein the comparing variations
includes determining that a human being is present if the
variations match the sinusoidal waveform.
19. A method of detecting the presence of a human being proximate
to a doll, the doll having a capacitive sensor including an RC
circuit, the method comprising the steps of: charging a capacitor
in the RC circuit; starting a counter to measure the discharge time
of the capacitor; storing a value of the discharge time in a memory
by a processor; repeating the steps of charging, starting, and
storing until a first plurality of discharge time values are stored
by the processor; comparing a mean value of the first plurality of
discharge time values to a reference value, the reference value
being associated with no human being proximate to the doll;
comparing the mean value of the first plurality of discharge time
values to a mean value of a second plurality of discharge time
values to determine whether a human being is proximate to the doll
in the event that the mean value of the first plurality of
discharge time values does not match the reference value; comparing
variations in the first plurality of discharge time values around
the mean value of the first plurality of discharge time values to a
sinusoidal waveform; and determining whether a human being is
proximate to the doll if the variations match the sinusoidal
waveform.
20. The method of claim 19, further comprising: activating an
effects generator in the event that the variations match the
sinusoidal waveform.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of prior U.S.
Non-Provisional patent application Ser. No. 11/571,789, which was
the National Stage of International Application No. PCT/EP05/08208,
filed Jan. 21, 2008, and entitled "Toy Sensitive to Human Touch,"
which claims priority to French Patent Application No. 04/07655,
filed Jul. 8, 2004, the disclosure of each of the two
above-identified applications is incorporated by reference herein
in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a toy including means for
detecting the approach of a portion of a living being, in
particular for the purpose of triggering an effect, e.g. a sound
effect, a light effect, or even a movement performed by said toy.
More particularly, the invention relates to a doll including means
for detection by the capacitive effect, combined with other
detection systems. The field concerned is that of toys and the
electronics in such toys.
BACKGROUND OF THE INVENTION
[0003] It is known to use capacitive effect detectors for actuating
effects in a toy such as a doll. The US patent application
published under the No. US 2004/0043696 discloses a toy including a
capacitive effect contactless detection system having a conductive
receiver plate, an effect activation circuit, and means for
interconnecting those two elements. The receiver plates can be
hidden inside the toy so as to avoid any detection system being
visible or apparent on the outside of the toy. When an object comes
close to one of the receiver plates, the capacitance measured at
that plate is modified. Consequently, by measuring the time
constant of an RC circuit, equal to the product R.times.C where C
is the capacitance of the plate and R is a resistance in the
circuit, it is possible to detect variations in said time constant
while discharging the RC circuit. The RC circuit discharge time is
thus measured and then compared with a reference value in order to
determine whether the capacitance has changed. Such a variation in
the discharge time means that an object is in the proximity of the
doll or the toy.
[0004] However, if a metal plate is brought up to the toy, the toy
detects the presence of the plate and therefore triggers its
effects. The toy thus appears to respond even though no portion of
a living being is in the proximity of the sensor. Such interference
can be caused in this way by any nearby metal object of large
weight or area.
SUMMARY OF THE INVENTION
[0005] An objective of the present invention is to remedy the
above-mentioned drawbacks. The invention thus proposes a detection
system avoiding that kind of interference. It is based on the fact
that the body of a living being transmits radio waves. More
precisely, the electrical power distribution network emits radio
waves having the same waveform as the electricity it distributes.
These waves are picked up by nearby living beings and
re-emitted.
[0006] The present invention thus provides a toy including at least
one capacitive sensor comprising a metal plate constituting one of
the two plates of a capacitor, the second plate being constituted
by a portion of a living being in the proximity of the toy,
[0007] at least one effects generator; and
[0008] a control circuit including means for causing effects to
take place in response to stimulation of said capacitive
sensor;
[0009] the toy being characterized in that said metal plate of said
at least one capacitive sensor is used as an antenna for picking up
radio frequency transmission from said portion of a living being in
the proximity of the toy.
[0010] Advantageously, the radio frequency transmission is at the
frequency of an electrical power distribution network.
[0011] In the preferred embodiment, the toy of the invention
advantageously comprises:
[0012] means for charging and discharging the capacitor of said at
least one capacitive sensor;
[0013] a counter for measuring the discharge time of said at least
one capacitive sensor;
[0014] means for starting the counter when the capacitor is
charged, and means for stopping the counter when the capacitor is
discharged;
[0015] a control circuit connected to the counter and having means
for storing a plurality of discharge times issued by the counter,
said plurality of discharge times constituting a collection, the
control circuit comprising means for analyzing the collection of a
plurality of discharge times, and means for detecting variation in
the mean value of the collection relative to the mean value of the
preceding collection, the control circuit also comprising means for
comparing variation in the values of the discharge times within a
single collection with a sinusoidal signal of frequency
substantially equal to the frequency of an electrical power
distribution network;
[0016] a resistor which is located between ground and the base of
the first plate of the capacitor of said at least one capacitive
sensor, the resistor and the capacitor thus constituting an RC
circuit; and
[0017] a variable frequency radio frequency generator generating an
electromagnetic field, at least one accessory including a passive
resonant circuit constituted by an inductor connected in series
with a capacitor and responsive to an electromagnetic field at a
determined frequency; and means for determining the presence of at
least one accessory and for stimulating the effects generator in
such a manner as to cause it to produce an effect.
[0018] In the preferred embodiment, the invention provides a doll
having a plurality of capacitive sensors situated at various
locations on the doll.
[0019] In another aspect, the invention provides a method of
detecting human presence for a toy including a capacitive sensor
having a metal plate constituting one of the two plates of a
capacitor, the second plate of the capacitor being constituted by a
portion of a living being in the proximity of the toy, said method
comprising at least the steps consisting in:
[0020] making a collection comprising a plurality of values for the
discharge time of the capacitor;
[0021] comparing the mean value of the collection with a reference
discharge time value;
[0022] comparing the mean value of the collection with the mean
value of the preceding collection; and
[0023] comparing any variations between the discharge time values
of the capacitor within the collection with a sinusoidal signal of
frequency substantially equal to the frequency of the electrical
power distribution network.
[0024] Advantageously, this second aspect of the invention
comprises the following characteristics:
[0025] it is concluded that a portion of a living being is present
when the variations in the discharge time values present
substantially the form of said sinusoidal signal;
[0026] it is concluded that a portion of a living being is present
if the mean value of the current collection is substantially equal
to the mean value of the preceding collection, and if it was
previously concluded that a portion of a living being was
present;
[0027] it is concluded that no portion of a living: being is
present when the mean value of the current collection is
substantially equal to a reference value;
[0028] the reference value is a function of external conditions;
and
[0029] the collection comprises ten discharge time values.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Other features and advantages of the present invention
appear from the following description of non-limiting embodiments,
given with reference to the accompanying drawings, in which:
[0031] FIG. 1 is a diagram showing a doll in accordance with the
invention;
[0032] FIG. 2 is a schematic of an electronic circuit associated
with a capacitive sensor plate in the FIG. 1 doll;
[0033] FIG. 3 is a flow chart of the detection method of the
invention implemented by the FIG. 2 circuit; and
[0034] FIG. 4 is a graph plotting variations in discharge time
within a collection during a contact.
DESCRIPTION OF THE INVENTION
[0035] FIG. 1 shows the preferred embodiment of the invention. It
shows a doll 1 having a plurality of sensors at various locations
of its body. These sensors may be of several kinds. Thus,
capacitive sensors 2 in accordance with the present invention are
situated on the feet, one of the wrists, and one of the cheeks of
the doll 1, while inductive sensors 3 are situated on the lips, the
chest, and the other wrist of the doll 1. Whereas the inductive
sensors 3 are used for detecting accessories that are not shown,
the capacitive sensors 2 are used for detecting the presence of a
portion of a living being in the proximity of the sensor. Other
sensors such as gravimetric or radio sensors (not shown) could also
be installed on the doll 1.
[0036] Each capacitive sensor 2 can lead to a different action
depending on its location in the body of the doll 1. By means of
this system, malfunction due to the presence of metal objects are
avoided.
[0037] The operation of the capacitive sensors 2 is shown in FIG.
2. A capacitive sensor 2 is constituted by a detection plate 5 and
a resistor 6 connected between the detection plate 5 and ground. On
the approach of a portion of a human being 4, the capacitor 50
formed by the detection plate 5 and the portion of the human being
4 changes so that the discharge time of the RC circuit formed by
the resistor 6 and the capacitor 50 is changed. An amplifier 7
serves to recharge the capacitor 50 so that a counter 8 measures
the discharge time of the RC circuit. The counter 8 co-operates
with the amplifier 7 by means of a start-count signal 81. Thus,
when the capacitor 50 has been charged by the amplifier 7, the
start-count signal 81 informs the counter 8 that it should start
counting. Similarly, a stop-count signal 82 serves to stop the
counter 8 and to inform a central processor unit (CPU) 9 that it
can read the data delivered by the counter 8 on a data bus 84. The
counter 8 and the CPU 9 are synchronized by means of a common clock
signal 83.
[0038] Consequently, in order to start charging the capacitor 50
constituted by the detection plate 5 and the portion of the living
being 4, the CPU 9 instructs the amplifier 7 to start charging by
putting the signal 81 in the one state. The amplifier 7 then
delivers electrical power to the detection plate 5 until it is
charged. When the capacitor 50 constituted by the detection plate 5
and the portion of the living being 4 has finished being charged,
the signal 81 changes to zero, thus stopping the amplifier 7 and
starting the counter 8. Once the capacitor 50 constituted by the
detection plate 5 and the portion of the living being 4 has been
discharged, a Schmidt comparator 10 puts the stop-counting signal
82 to zero, thus stopping the counter 8 and informing the CPU 9
that it should store the discharge-time value present on the bus
84.
[0039] By repeating this operation a certain number of times, a
collection of discharge time values stored in a memory (not shown
in the figure) by the CPU 9 is built up, and on the basis of this
collection analysis described below makes it possible to determine
whether a living being is indeed in the proximity of the doll 1.
This system presents the advantage of being simple and easy to
implement. It can then co-operate with the CPU 9 in such a manner
as to implement the method shown by the flow chart of FIG. 3.
[0040] In addition, the detection plate 5 acts as an antenna for
receiving the radio waves transmitted by the nearby portion of a
living being. This has the effect of causing the time required for
the capacitor 50 to discharge to vary over time, with this
variation presenting the form of a sinusoidal signal having the
same frequency as the frequency of the electrical power
distribution network.
[0041] In FIG. 3, a flow chart shows how the detection method in
accordance with the invention runs. The method takes place in two
distinct stages P1 and P2, P1 being the sampling stage during which
a collection of discharge time values for the capacitor 50 is built
up using the circuits shown in FIG. 2, and stage P2 being the
analysis stage during which the data collected during the stage P1
is analyzed.
[0042] The stage P1 begins with initializing the system (S100).
During this step (S100), the value of N is initialized to 10. This
value determines the number of discharge times that go to making up
a single collection.
[0043] As explained above when describing FIG. 2, the capacitor 50
is charged during the next step (S110). Once the capacitor 50 is
charged, the counter 8 is started in the next step (S120). The
capacitor 50 discharges at this time. The detector 10 serves to
detect the end of capacitor discharging in the next step
(S130).
[0044] Once the capacitor 50 is fully discharged, the stop-count
signal is activated and the CPU stores the value presented by the
counter 8 in the next step (S146). A test serves to determine the
value of N (S150). If the value of N is not zero, then N is
decremented in a step (S151) and another charge cycle is begun: the
method returns to step (S110). When the value of N is zero in test
step (S150), then the stage P1 has terminated and a collection of
ten values has been built up in the memory of the CPU 9.
[0045] The stage P2 serves to analyze the data collected during the
stage P1. Initially, the mean value of the collection is compared
with a reference value. If the mean value is substantially equal to
the reference value, then it can be concluded that there is no
portion of a living being in the proximity of the detector 5
(S161). Otherwise, if the mean value of the collection is not
substantially equal to the reference value, then said current mean
value of the collection is compared with the mean value of a
preceding collection (S162). If these two mean values are
substantially identical and if during the preceding cycle it was
concluded that a portion of a living being was in the proximity of
the detector of the invention, then it can again be concluded that
said portion continues to be in the proximity of the detector.
Otherwise, if the mean collection values are not identical, or if
it was not decided previously that a portion of a living being was
in the proximity of the detector, then the process continues to the
next step (S163).
[0046] During step S163, variations in the values of discharge time
around the mean value of the collection are compared with a
sinusoidal signal of frequency substantially equal to the frequency
of the electrical power distribution network. FIG. 4 is a graph
showing the discharge times T1 to T10 of a single collection. These
discharge times T1 to T10 vary about a collection mean value Tmean.
During step S163, the CPU 9 looks for a sinusoidal waveform at a
frequency substantially equal to the frequency of the electrical
power distribution network in the variations in the values T1 to
T10 of the discharge time. If, as is the case in FIG. 4, it is
possible to superpose such a sinusoidal signal on the discharge
time values T1 to T10, then it is concluded that a portion of a
living being is present in the proximity of the detector.
Otherwise, it is concluded that there is interference from a metal
object (S166). The method then terminates with a conclusion step
(S170) which causes effects to be activated if it has been
concluded that a portion of a living being is present in the
proximity of the detector.
[0047] In an embodiment, the reference value of step (S161) is
readjusted as a function of external conditions such as the
temperature, the pressure, or indeed the humidity of the
surrounding air.
* * * * *