AN ALARM SYSTEM FOR ALERTING A DRIVER TO THE PRESENCE OF AN ABANDONED LIVING BODY IN A VEHICLE

FIELD OF THE INVENTION [0001] The present invention relates generally to the safety of living bodies in vehicles. More specifically, the invention discloses a system that generates an alarm signal when the motor of a vehicle is switched off, and yet a living body such as a baby, is present in the vehicle.

BACKGROUND OF THE INVENTION

[0002] Vehicles such as private cars are used, inter alia, for the transportation of living bodies such persons like, children, toddlers, babies and the like and/or animals such as dogs, cat and the like. Unfortunately, a driver may unintentionally forget, e.g., the baby, in the vehicle. Forgetful abandonment of a living body may have lethal consequences. For example, as a result of forgetting a baby in the vehicle, said baby may choke to death, suffer from a heatstroke, or be exposed to other dangers such as abduction. Accordingly, several systems and/or methods have been devised for notifying drivers that a living body was abandoned in a vehicle. [0003] Examples of known systems are described in U.S. Pat. Nos. 5,793,291, 5,581,234, 5,949,340, 5,966,070 and 6,104,293.Economically viable versions of known systems and apparatuses rely upon child occupant sensors that are likely to be activated by stimuli other than that invariably associated with an actual child. For example, weight or pressure sensors will be activated if objects are placed purposefully or in the occupied baby car seat. As a result, false alarms are common. This problem is further aggravated in the presence of a child "occupant" signal, since existing systems are designed to activate an alarm if the vehicle ignition is turned off so that false alarms are very common in present systems. As a result, many drivers have learned to ignore alarms indicative of children remaining unattended in a baby car seat within the vehicle. [0004] Drivers are thus likely to exit the vehicle in spite of the alarm signals, as each alarm requires the driver to consider whether the alarm signal is actually indicative of an abandoned child or not, thus nullifying the intended benefit of the system

[0005] Further, none of the existing systems offers a completely reliable method of notifying the driver' once having departed the vehicle' of the need to return to the abandoned child.

[0006] Therefore, a new and improved system for the safe transport of babies is needed. There is a demand for a reliably warning that a child has been left in a car seat, and the present invention will eliminate false alarms while providing a maximally reliable monitor for a departing driver.

SUMMARY OF THE INVENTION [0007] The aim set forth is attained by means of a proposed system comprising sensors of the presence of living bodies such as, e.g., a baby, a pet. The sensors are made in the form of light guides, transmitting and receiving sections as well as a control subsystem and the signaling element itself. The main structure and operation of the present invention is described below: [0008] In embodiments of the invention, light guides may be positioned in the front parts of the seats, for example, in the region of the seams in each seat cover, [0009] In embodiments of the invention, separate sources of light pulses in the transmitting section may be coupled to one end of light guides- sensors of presence of living bodies in a vehicle. In embodiments of the invention, receivers of light pulses from the receiving sections may be coupled to opposite end of light guides. In embodiments of the invention, the pulse sources may be made in a form of concurrently switched light diodes connected to one pulse generator in transmitting section. In embodiments of the invention, Photo sensors such as, e.g. photodiodes, may be used as receivers of light pulses in the receiving section. In embodiments of the invention, these photo sensors may be connected at the output to the differential amplifier in the receiving unit.

[0010] In embodiments of the invention, the system may include a bandpass filter at the output connected to a threshold element (detector) with signal timer at the output switched on to the signaling unit itself for sending an alarm signal, wherein the output of bandpass filter may be connected to a control subsystem key and may also connected to a circuit of transmitting section timer.

[0011] In embodiments of the invention, the system is based on the established phenomenon of changing the light guide (e.g. optic-fiber cable) characteristics by deformation. Any deformation of the light guide, in particular under the action of

pressing (compressing) or bending (displacement), may change optical parameters of light guide (e.g. first refractive index), and hence the light properties, such as the level of the output signal that corresponds to light intensity output.

[0012] In embodiments of the invention, the proposed system may generate a differential signal in the receiving section. After a predetermined number of transformations the system may trigger alarm signal reminding the driver of the living body (e.g. a baby) that has been left in the vehicle, each time the driver exits from the vehicle.

[0013] In embodiments of the invention, the system reacts correspondingly to the persistent living body movements as well (signaling the living body's uneasiness and other problems), thus attracting attention of the driver as well as strangers.

γAAI δλ T-n pmKnrlimAnfc ¹ n-f ilte _* iTitrpTTrmn tϊna OTrc+om -ic KiWnrrhfr TI C A in when installing a baby or children vehicle seat in the vehicle and is correspondingly disengaged when taking the vehicle seat out. [0015] In embodiments of the invention, the system may be adjusted in such a way as to permit the driver, which may be the mother of a baby or owner of a dog remaining in the vehicle for a relative short period of time.

[0016] In embodiments of the invention, the system can be also equipped with additional elements, contracts and small parts permitting to react for surpassing temperature, etc.

BRIEF DESCRIPTION OF DRAWINGS

[0017] The subject matter regarded as the invention will become more clearly understood in light of the ensuing description of embodiments herein, given by way of example and for purposes of illustrative discussion of the present invention only, with reference to the accompanying drawings (Figures, or simply "FIGS."), wherein:

[0018] FIG. 1 is a schematic depiction of the entire system of the present invention;

[0019] FIG. 2 is a schematic depiction of in further details the transmitting unit;

[0020] FIG. 3 is a schematic depiction of in further details the receiving unit; [0021] FIG. 4 is a schematic depiction of in further details the servo control system; and;

[0022] FIGS. 5 -19 are schematic depictions of the relationship between energy weight, signal energy, and location of energy and the presence of a living body in a vehicle.

[0023] It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention discloses a system for alerting a driver of a human body such as, e.g., a baby, a dog, left alone in a vehicle. According to some embodiments of the invention, the system is based on sensors that are made in the form of optical waveguides, which may be suitably adjusted on the surface of a seat within the vehicle. Accordingly, waveguides may be, for example, adjusted to the driver's seat and the child's seat. [0025] The optical waveguides serve as reliable movement sensors, as they are configured to react to changes and movements in their immediate physical environment by affecting the properties and the intensity of the light traveling through them. By comparing the light properties (e.g. light intensity) coming from both waveguides and checking it according to a predefined threshold, the system may detect situations where, for example, the driver left the vehicle but left therein a living body such as, a baby, and subsequently set on the alarm.

[0026] Referring now to FIG. 1, the entire system 100 is depicted according to one embodiment of the invention. The system may be comprised of a transmitting unit 200, a receiving unit 300, a servo control unit 400 and an alarm unit 130, all of which are operatively associated with each other. [0027] According to some embodiments of the invention, the first optical waveguide 101 and the second optical waveguide 102 pass through connectors 103 and 104 respectively and may be connected to the vehicle's vehicle seats, specifically on the region of the seat cover seam. [0028] According to some embodiments of the invention, one end of each of the first optical waveguide 101 and the second optical waveguide 102 is coupled to a first light source 105 and a second light source 106, respectively.

[0029] According to some embodiments of the invention, the other end of each of the first optical waveguide 101 and the second optical waveguide 102 may be coupled to a first light sensor 123 and a second light sensor 122, respectively.

[0030] According to some embodiments of the invention, the said light sources 105,106 may be in the form of, for example, light emitting diodes (LED) or any other suitable light source, and may be connected to a pulse generator 150. [0031] According to some embodiments of the invention, light sensors 123,122 may be in the form of photodiodes or the like and are adapted to serve as receivers for the light coming from said optical waveguides 101,102. Each output of said light sensors 123,122 may be connected through preamplifiers, 125 and 124 respectively, to the inputs of a comparator 126 respectively. Said comparator 126 may be in the form of an operational differential amplifier. [0032] According to some embodiments of the invention, comparator 126 is connected in its output to the input of a band pass filter 127, which is connected in its output to the input to the input of a threshold detector 128.

[0033] According to some embodiments of the invention, threshold element 128 may be connected in its output to the input of a signal timer 129, which is connected in its output to the input of the alarm unit 130. In Addition, the output of the said band pass filter 127 may also connected in its output to a switch 114 of the servo control unit 400. The said switch may also be connected to a timer circuit 108 in the transmitting unit 200. [0034] The transmitting unit 200 may comprise a current regulator 109, a timer circuit 108, a switch 107 and the two light sources 105 and 106, all of which are operatively associated with each other.

[0035] The receiving unit 300 may comprise two light sensors 123 and 122, two preamplifiers 124 and 125, a comparator 126, a bandpass filter 127, a threshold detector 128 and an output signal timer 129, all of which are operatively associated with each other.

[0036] The servo control unit 400 may comprise a switch 114, an integrator circuit 113, a driver circuit 112 and a variable resistor 111, all of which are operatively associated with each other. [0037] According to one embodiment of the invention, the optical waveguides may be, but are not limited to, fiber optics made of low silicone polymer clad and a glass core. [0038] Referring now to FIG. 2, the transmitting unit 200 is depicted in greater details. Current regulator 109 may be in the form of an integrated circuit and a resistor Rl. [0039] According to one embodiment of the invention said integrated circuit 109 is a three terminal regulator. Timer circuit 108 comprises of an integrated circuit for

generating accurate time delay or oscillations. The switch may include a general purpose n-p-n transistor Ql.

[0040] According to some embodiments of the invention, timer circuit 108 generates voltage pulses that are connected to the base of the on-off transistor Ql switch. When there are no pulses coming from timer circuit 108, the transistor Ql is set to an open ("off) mode. After a period of approximately two milliseconds pulse, arriving from Timer 108, the transistor Ql is set to a closed ("on") mode. So that current is passed from current regulator 109 to both light sources 105 and 106. The current pulse through said light sources results in optical radiation being generated for transmission through the optical waveguides lOland 102 through connector 103 and 104. The pulse duration and the pulse interval may be determined by the values of resistors R2 and R3 and capacitor Cl connected to the terminal of the timer chip 108. [0041] According to one embodiment of the invention a pulse of approximately 2 milliseconds duration with a pulse interval of approximately 2 milliseconds duration is produced. As explained below in further details, a potentiometer R4 is connected in parallel to light source 105, in order to provide a rough adjustment of the light intensity traveling through optical waveguide 101.

[0042] Referring now to FIG. 3, the receiving unit 300 is depicted according to one embodiment of the invention. The ends of the optical waveguides 101 and 102 are connected to light sensors 123 and 124 via connector 121 and 120 (see FIG. 1). In case light sensors 123 and 122 are photodiodes, their corresponding anodes shall operate in the photovoltaic mode. The light sensors are connected in their output to the inputs of two corresponding pre-amplifiers 124 and 125. [0043] Said pre-amplifies 124 and 125 may be based on field effect transistors, in order to provide high impedance input coupled with low noise throughput. The current generated by light sensors 123 and 122 as a result of incident light on optical waveguides 101 and 102 strands creates a voltage across resistor R5 and R6 respectively. Both preamplifiers 124 and 125 are substantially identical with regard to arrangement and value of components. The small adjustable capacitances parallel to resistors R5 and R6 reduce the bandwidth of the amplifiers and, thus, eliminate high frequency noise.

[0044] The output from the two preamplifiers 124 and 125 is connected to a comparator 126 that may be in the form of a differential amplifier via resistor R9, whereas the normal polarity input is connected to the 'ground' by means of resistor

RlO. This is the circuit of a conventional differential amplifier. The gain of this amplifier is controlled by the ratio of resistors R9, RlO to resistor R7, R8. Offset voltage of the differential amplifier is reduced to zero by potentiometer RIl connected to the off-set adjustment leads of the device. The device is operated from a VCC (e.g. 15V) power supply. Capacitor C3 filters noise from the power supply. The purpose of the comparator/differential amplifier 126 is to amplify any voltage difference between the output from preamplifiers 124 and 125.

[0045] The output from comparator 126 is connected to a bandpass filter 127. The appropriated combination of three resistors R12, R13, R14 and two capacitors C3, C4 provides a narrow bandpass characteristics. For example, in one embodiment of the invention, the active filter possess center frequency of substantially 250 Hz and a bandwidth of substantially 25 Hz at the 3 db point (Q=IO). Only the first sinusoidal harmonics of the signal generated by transmitting unit 200 may be passed by such a filter. In this way any extraneous noise introduced by light sensors 8 preamplifiers 34 and differential amplifier 34 is eliminated.

[0046] The output from the bandpass filter 127 may be connected to a threshold detector 128. The combination of capacitor C5 and resistor R15 at the input provides for AC coupling. The resistors network comprising of potentiometer R16 and resistor R17 allows for a threshold adjustment for triggering the device. The potentiometer R16 may be adjusted for a large threshold level of 50 millivolts. If the input exceeds this level of a large 10V signal appears at the output of the threshold detector 128. Either a positive or a negative signal exceeding the 50 millivolt level may cause a 10V signal output.

[0047] The output of threshold detector 128 is connected to an output signal timer 129. This device provides for an output signal of fixed duration each time the threshold device generates an output signal. The combination of circuit components and timer chip makes a monostable mutivibrator. The resistors R18, R19 and capacitor C7 provide for AC coupling of the signal into the outer signal timer 129 and proper bias voltage for operation thereof. [0048] Duration of the output signal is determined by resistor R20 and capacitor C7. Signal duration value may be chosen to provide for an output signal up to several minutes. The output signal lasting, e.g., one minute, activates a relay for this duration signal. Any external alarm indicator such as a loudspeaker, buzzer, bell, light, tape recorder and the like, may be turned on by the closure of relay contacts. As an

example, FIG. 3 shows activation of a buzzer 130 by a relay 131. After closing the relay 131 contacts, buzzer 130 is connected to a VCC power source. The two diodes Dl and D2 protect the integrated circuit chip (output signal timer 129) from voltage spikes which may be generated by relay coil 131. [0049] Referring now to FIG. 4, the servo control unit 400 is depicted according to one embodiment of the invention. As stated earlier, its purpose is to maintain the light input to preamplifiers 125 and 124 balanced without affecting the transient response obtained from a signal about the abandoned living body, which may be, for example, a baby. [0050] Switch 114 is the first element of servo control system 400. It connects the output of bandpass filter 127 with the input of integrator circuit 113. Switch 114 may be configured to be normally opened and closes only after receiving signal from the timer circuit chip 108. When the signal coming from the timer circuit chip 108 activates the switch 114 and causes its closing, the signal from the bandpass filter 127 is passed on to the input of the integrator 113. The integrator circuits acts as a low pass filter due to the configuration of operational amplifier 162, resistors R21, R22, R23 and capacitor ClO, and passes the signal further to the operational amplifier 161 and resistors R24 and R25 and R26 in a circuit that acts as a driver circuit 112. The operational amplifier 161 is further connected in its output to a transistor Q2 that is connected to the ground in one leg and to the connection between the two light sources

105 and 106. Thus, current may be bypassed from the light sources 105 and 106 by said transistor Q2. Depending on the voltage sent by the integrator 113 and the driver 112, voltage at transistor Q2 of variable resistor 111 base goes up or down, thus increasing or decreasing current flow through resistor R27. If the current through the transistor Q2 increases, current through 105 decreases and radiation output from this light emitting diode decreases and vice versa. [0051] During operation light pulses are generated by light emitting diode 105 and

106 driven by electric current pulses generated by timer 108 and switch 114, and constant current source 150. Light pulses from 105 and 106 are propagated through optical fibers 101 and 102. Radiation generated by diodes 105 and 106 transmitted via optical fibers 101 and 102 arc received by photodiodes 123 and 122. Output from each channel comprising light emitting diodes 105 and 106, optical fibers 101 and 102, photo detectors 123 and 122 and preamplifiers 125 and 124 is directed to a comparator in the form of a differential amplifier 126. Provided that the light output from 105 and

106 are properly adjusted, both channels can be balanced in such a way that photo detectors 123 and 122 output becomes equal. Therefore, comparator/differential amplifier 126 output is zero and subsequent circuits 127, 128, 129, and 130 become inoperative. [0052] If said light channel is excited anywhere in either optical waveguides 101 or 102, optical loss occur in that zone and less light is received by detectors 123 or 122 respectively.

[0053] Such pressure changes occur as a result stepping on optical fiber 101 or 102 when the driver leave the vehicle with the living body, which may be a child, inside for the period of time longer than a predefined period in the timer system. Radiation received by detectors 123 and 122 is no longer equal due to the optical loss in one of the fibers caused by the driver's exit, from the vehicle. This signal difference is strongly amplified by comparator/differential amplifier 126. After passing through bandpass filter 127, differential voltage is incident on a threshold detector 128. If the signal exceeds a predefined threshold, then threshold device 128 produces high voltage signal triggering timer circuit which in turn activates alarm device 130 for a predefined period of time.

[0054] By comparing voltage levels at diodes 123 and 122 and amplifying the difference in differential amplifier 126 rather than measuring absolute values, highly sensitive system may by implemented. In order to prevent high false alarm rates any noise peaks amplified by differential amplifier 126 and triggering threshold device 128 must be suppressed. This may be achieved by using narrow band pass filter 127 that transmits signals generated only by transmitting unit 200 and thus rejecting noise peaks generated by photo diodes 123 and 122, preamplifiers 125 and 124 or differential amplifier 126.

[0055] Besides noise pulses triggering threshold device, long term drift from one fiber output in respect to another fiber has to be controlled. In practice, temperature difference of the environment where fibers 101 and 102 may be in place, or changes in temperature difference of the environment where fibers 101 and 102 are placed, or changed in temperature difference in electronic devices can cause slow drift of detectors 123 and 122. Small difference can be amplified by differential amplifier 126 and the signal may be transmitted to band filter 127, eventually triggering threshold device 128.

[0056] Slow voltage changes are sampled by servo control loop 400. Small voltage difference appearing at band filter 127 output charges capacitor C8 in the integrator circuit 113. Voltages at this capacitor appearing at the output of integrator 113 are amplified and used to control current of transistor Q2 of variable resistor 111. The current in transistor Q2 is controlled by the output from integrator 113. Depending of voltage polarity, current in transistor Q2 is either increased or decreased. Since transistor Q2 and light source 105 are fed from current source 150, sum of current in both devices is constant. Therefore, by controlling current in transistor Q2 current in light source 105 is adjusted and thereby light output of this light source is adjusted as well. The amount of control is dependent on the gain of the feedback loop which is in turn determined by the integrator 113.

[0057] When there is no living body in the vehicle, the driver may simply switch of the alarm system, thus preventing the alarm from operating. According to yet another embodiment of the invention, whenever there is a vehicle seat with a living body such as e.g. a child, a baby, and the like; an animal such as e.g., a dog, a cat and the like, in it present in a vehicle, the ignition switch may be turned on only after the alarm system has been switched on, thus offering an extra precaution measure. [0058] The threshold that determines according to which it may be detected when a living body is left abandoned in a vehicle may be set as will be outlined hereinafter with reference to Fig. 5-19. For example, an indication of a presence of a living body may be determined according to the energy of the signal in the fiber, the location where energy of the signal exists and the energy weight.

[0059] As can be readily seen in Figs. 5-19, when a living body such as, e.g., an adult person, is present in the vehicle, the energy weight is closer to 0 than in case there is no living body present in the vehicle. These parameters form the so-called signature of the object that affects the light properties within the waveguide. Conversely, when there is no living body person present in the vehicle, the energy weight will be more distant from 0. However, as can be seen in the table presented in Fig. 19, system 100 may have to be calibrated according to the type of vehicle and/or weight of missing body to be detected. Alternatively or additionally, the threshold for each vehicle and/or living body to be detected may be determined by, e.g., calculating a weighted average by taking into account all three above-mentioned parameters (energy weight, location and/or signal energy).

[0060] In the above description, an embodiment is an example or implementation of the inventions. The various appearances of "one embodiment," "an embodiment" or

"some embodiments" do not necessarily all refer to the same embodiments.

[0061] Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment.

[0062] Reference in the specification to "some embodiments", "an embodiment", "one embodiment" or "other embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the inventions.

[0063] It is understood that the phraseology and terminology employed herein is not to be construed as limiting and are for descriptive purpose only. [0064] The principles and uses of the teachings of the present invention may be better understood with reference to the accompanying description, figures and examples.

[0065] It is to be understood that the details set forth herein do not construe a limitation to an application of the invention.

[0066] Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in embodiments other than the ones outlined in the description above.

[0067] It is to be understood that the terms "including", "comprising", "consisting" and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers.

[0068] If the specification or claims refer to "an additional" element, that does not preclude there being more than one of the additional element.

[0069] It is to be understood that where the claims or specification refer to "a" or "an" element, such reference is not be construed that there is only one of that element. [0070] It is to be understood that where the specification states that a component, feature, structure, or characteristic "may", "might", "can" or "could" be included, that particular component, feature, structure, or characteristic is not required to be included.

[0071] Where applicable, although state diagrams, flow diagrams or both may be used to describe embodiments, the invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described. [0072] Methods of the present invention may be implemented by performing or completing manually, automatically, or a combination thereof, selected steps or tasks. [0073] The term "method" may refer to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the art to which the invention belongs.

[0074] The descriptions, examples, methods and materials presented in the claims and the specification are not to be construed as limiting but rather as illustrative only. [0075] Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined.

[0076] The present invention can be implemented in the testing or practice with methods and materials equivalent or similar to those described herein.

[0077] Any publications, including patents, patent applications and articles, referenced or mentioned in this specification are herein incorporated in their entirety into the specification, to the same extent as if each individual publication was specifically and individually indicated to be incorporated herein. In addition, citation or identification of any reference in the description of some embodiments of the invention shall not be construed as an admission that such reference is available as prior art to the present invention.

[0078] While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the embodiments. Those skilled in the art will envision other possible variations, modifications, and applications that are also within the scope of the invention. Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents. Therefore, it is to be understood that alternatives,

modifications, and variations of the present invention are to be construed as being within the scope and spirit of the appended claims.