This application claims priority from German Patent Application No. 102008050640.0, which was filed on Oct. 7, 2008, and claims priority from German Patent Application No. 102008056252.1, which was filed on Nov. 6, 2008, and which are incorporated herein by references in their entirety.
The present invention relates to devices and methods for sensing respiration or a respiration activity on the part of living beings, e.g. humans or animals.
What is referred to as respiration activity is the variation in the body's circumference at at least one location on the torso, e.g. on the rib cage, of a living being. Typically, with human beings, respiration activity is measured at two locations on the torso, at the level of the abdomen and the torso, and is mapped as a signal or stored.
From the raw signal of respiration activity, vital parameters such as breathing rate, breathing amplitude and breathing volume are calculated, which provide valuable information about the condition of the person. Generally, a statement may be made about the condition of a person or patient by means of respiration activity, either on its own or in combination with other vital parameters.
Conventional methods are based on measuring respiration activity by means of straps placed around a body part. The method by means of which respiration activity is determined may be classified into two categories. On the one hand, these are no-load methods and, on the other hand, they are methods which involve a certain amount of tension of the straps. An example of a no-load method is inductive plethysmography, wherein the straps are loosely placed around the selected body parts. Irrespective of the method of measurement, such straps may be worn underneath the clothing, but may be connected, underneath the clothing, to signal processing electronics underneath the clothing via cables.
U.S. Pat. No. 5,825,293 describes a method of monitoring the breathing rate by means of detecting the changes in the magnetic field of a permanent magnet attached to the body of the patient.
A disadvantage of respiration straps is that they may be placed on the body and be connected to signal processing electronics prior to measurement.
A disadvantage of the method wherein the magnets are integrated into a piece of clothing is that the respective patient has to wear such a piece of clothing provided with a magnet, or may put it on beforehand.
According to an embodiment, a device for sensing respiration of a living being may have: an active transmitter configured to generate a magnetic or an electromagnetic field; and a sensor arranged on the torso of the living being and configured to provide a signal which depends on the magnetic or electromagnetic field and on a change in the distance, caused by the respiration of the living being, between the active transmitter and the sensor.
According to another embodiment, a method of sensing respiration of a living being may have the steps of generating a magnetic or electromagnetic field by means of an active transmitter; and providing a signal by means of a sensor arranged on the torso of a living being, the signal depending on the magnetic or electromagnetic field and on a change in the distance, caused by the respiration of the living being, between the active transmitter and the sensor.
According to another embodiment, a measuring system for sensing respiration of a person situated within a motor vehicle may have: an active transmitter integrated into a backrest of a car seat of the motor vehicle and configured to generate a magnetic or electromagnetic field; and a sensor arranged within a safety belt of the motor vehicle, in a state in which the safety belt is fastened, at the height of the person's torso, and configured to provide a signal which depends on the magnetic or electromagnetic field and on a change in the distance, caused by the respiration of the living being, between the active transmitter and the sensor.
Embodiments of the method and of the device enable performing measurements of respiration activity with reduced impairment of the person or, generally, of a living being.
In embodiments of the method and of the device, the devices for measuring respiration activity, the active transmitter and the sensor are integrated into environment objects with which a person or, generally, a living being comes into direct contact. Examples of such environment objects are the backrest of a car seat, and the safety belt.
Embodiments of the device and of the method do not presuppose that so-called application parts, i.e. parts which are mounted or attached to the patient's body (e.g. respiration straps), be placed around the body for measuring respiration activity.
Embodiments of the device and of the method may be readily integrated into so-called “environment objects” of the person, e.g. operating elements, seats, beds, safety belts, steering wheels, etc., such that from the outside, they are inconspicuous or cannot be seen. Thus, the measurements of the person or the living being may be performed without being noticed or without involving any additional effort on the part of the person, such as placing the respiration straps or putting on corresponding pieces of clothing.
Embodiments of the device and of the method may further be used in such places or cases where respiration straps or specific pieces of clothing cannot be used because of hygienic and technical problems or because of non-acceptance by patients.
In embodiments of the present invention, the active transmitter is configured to adapt the device for sensing to varying conditions of measurement by changing, for example, the frequency or amplitude of the magnetic or electromagnetic field. For example, the transmitting power may be increased or reduced, depending on the average distance between the active transmitter and the sensor, which is a measure of the thickness of the torso, or rib cage, so as to enable reliable measurement but at the same time to keep the power consumption low, for example. Thus, optimum measurement is enabled irrespective of the circumference of the torso of the living being.
In further embodiments of the device and the method, wherein not all of the components of the measuring system or of the device can be integrated into environment objects of the person or other living beings, individual components of the device for sensing may be attached to the body of the person or living being. This is still simpler and faster than utilizing the conventional respiration straps, for example.
Embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:
Embodiments of the present invention will be explained below in more detail with reference to the accompanying figures, wherein:
a shows a schematic drawing of an embodiment of a device for sensing respiration of a living being;
b shows an embodiment, in accordance with
a shows a schematic representation of an embodiment of a device for sensing respiration of a living being, said device being integrated into a backrest of a car seat and into a safety belt, the measurement signal being communicated to the evaluation means via a wireless interface;
b shows a schematic representation of an embodiment of a safety belt and of a sensor for wireless transmission of the measurement signals;
a shows a schematic representation of an embodiment of a device for sensing respiration of a living being, said device being integrated into a backrest of a car seat and into a safety belt, the wireless transmission of the measurement signals being effected by means of load modulation or back-scattering methods;
b shows a schematic representation of an embodiment of a safety belt comprising an integrated transponder as a sensor;
The term measuring system may also be used for the term device for sensing, the terms transmitter device or transmitter unit may also be used for the term active transmitter, the terms receiver device or receiver unit may also be used for the term sensor, the terms first and/or second object or environment object may also be used for the first and/or second means.
In the following, identical reference numerals will be used for objects and functional units which have identical or similar functional properties, repeated descriptions of said objects and functional units being dispensed with in order to avoid unnecessary repetitions.
a shows a schematic representation of an embodiment of a device 100 for sensing respiration of a living being, in this case of a person, said device being integrated into an automotive environment.
The device 100 for sensing comprises an active transmitter 10 and a sensor 30, the active transmitter being configured to generate a magnetic or electromagnetic field, and the sensor being configured to provide a signal which depends on the magnetic or electromagnetic field and on a change in the distance, caused by the respiration of the living being, or person, between the active transmitter 10 and the sensor 30. In this context, the sensor 30 is arranged on the torso of the living being.
In the embodiment shown in
Further embodiments (see
In the embodiment shown in
In this context, the term “integrated” is generally used below irrespective of whether the active transmitter 10 and/or the sensor 30 are entirely or partly arranged within or outside of the first or second means 110, 130.
In further embodiments, the first or second means 110, 130 is a bed or a lying surface, for example, and the correspondingly other means may be a belt which may be connected to the bed or lying surface, or a cushion, for example, into which the active transmitter or the sensor is integrated.
a shows an embodiment of the device for sensing respiration, wherein the first means 110 and the second means 130 are connected to each other, in
In further embodiments, a safety belt as the second means 130 is connected to the bed or the lying surface as the first means 110 so as to reliably measure a change in the distance, which is caused by the respiration, despite a turning of the torso.
Even though the embodiment in
Generally, it may therefore be said that the device for sensing or for measuring respiration activity comprises an active transmitter 10, which is also referred to as a transmitter device, and a sensor, which will also be referred to as a receiver device 30 below. wherein the measurement is based on a change in the distance between the transmitter unit and the receiver unit and may therefore be sensed by means of metrology. The measurement signals within the receiver may be caused by different physical mutual influences between the transmitter unit and the receiver unit, e.g. by magnetic fields or electromagnetic fields.
What follows is a more detailed description of embodiments which are based on actively generating a magnetic field on the part of the transmitter device 10, i.e. on inductive coupling. In such embodiments, the device 100, which will also be generally referred to below as a measuring system, essentially consists of two coils which are loosely inductively coupled to each other. The primary coil may be integrated into an object, e.g. a car seat or an operating table, and generates an alternating magnetic field having a specified frequency, amplitude and/or phase position. For stabilizing purposes or for measuring interference effects or for measuring amplitude fluctuations, the transmitting unit and possibly also the receiving device may comprise additional measuring coils, or additional measuring coils may be integrated in the environment object.
For measuring respiration activity, a secondary coil or a secondary coil system is attached, as a sensor, at a specific distance from the primary coil or primary coil system of the active transmitter 10, to the object to be measured in such a manner that a change in the movement between the two coils or coil systems will be reflected in the form of a measured quantity. In embodiments based on inductive coupling, the measured quantity to be determined, or the signal to be generated, is a change in the induced voltage generated within the secondary coil, said change being due to the positional deviation of the secondary coil in relation to the primary coil. In this context, what is sensed and evaluated is not the induced voltage itself, but the change in the induced voltage, which is due to the positional deviation from a static position or starting position.
Data communication of the measurement signal thus generated may be effected in several ways: a) the measuring unit, or sensor, 30 may be wire-connected to the evaluation unit, b) the sensor 30 may be wirelessly connected to the evaluation unit, e.g. via Zigbee or Bluetooth (not shown in
b shows an embodiment of a device for sensing respiration of a person, wherein the breathing rate of the person in the automobile is to be monitored. The active transmitter 10 and the sensor 30 are inductively coupled. The active transmitter 10 comprises a primary coil and possibly further reference coils integrated into the backrest of the car seat 110. The active transmitter 10 is configured to generate the magnetic field by means of a current fed into the primary coil. The sensor 30 comprises a secondary coil and is integrated into the safety belt 130. For example during the ride, or when the safety belt is fastened, the safety belt 130 is firmly applied to the driver's rib cage. By means of the inductive coupling, the magnetic flow generated by the primary coil flows through the secondary coil and in the process induces a voltage which may be increased even more by means of a resonant circuit with a parallel capacitor. By means of a subsequent demodulation circuit, it is not the induced voltage itself that is determined, but a change in the induced voltage. Thus, the driver's respiration activity may be monitored. If the driver is not breathing, the measuring circuit does not generate any measurement signal, or merely generates a “zero signal”.
As was set forth above, conventional respiration measuring systems involve applying so-called “application parts” (e.g. respiration straps) to the driver, but this is not necessary here. Once the person has got into the vehicle and once the safety belt has been fastened, measurement of respiration may start immediately. Thus, respiration monitoring even of changing drivers is readily possible. The system components and the supply lines may be designed such that they are inconspicuous or are even not visible from outside.
Sensing or measuring the signals which are a measure of the driver's respiration activity is possible during the ride, so that an evaluation of the condition of the driver of the vehicle by utilizing the quantities derived from the measurement signal or raw signal is also possible during the ride.
In the embodiment, shown in
Alternative embodiments transfer the data from the sensor to the evaluation unit via radio transmission, load modulation, back-scattering methods or similar methods.
The previously described embodiments related to signal changes, or changes in the signal 328, which are caused by a change in the distance between an active transmitter 10 and a sensor 30 which are inductively coupled to each other. Alternatively, embodiments may also comprise other coupling mechanisms instead of inductive coupling between the active transmitter 10 and the sensor 30, for example electromagnetic coupling.
The active transmitter 10, or the transmitter unit 10, of an embodiment comprising electromagnetic coupling includes, for example, a dipole or patch antenna which is supplied by a high-frequency signal. Signal generation itself is similar to the inductively coupled systems or embodiments. The same applies to embodiments of the receive antenna, the receive signal change of which, caused by a change in the field strength, is used for deriving respiration activity. Similarly to the active transmitter 10, the sensor 30 comprises dipole or patch antennas, for example.
Subsequently, the detected receive signal is further processed and evaluated in a manner similar to inductively coupled embodiments. In the case of embodiments having a transponder as the sensor, a back-scattering method is used instead of load modulation for transferring the measurement signal to the evaluation unit. Embodiments having a transponder as the sensor have the advantage that they make do without any additional power supply for operation on top of that for the active transmitter, but that the power supply is effected by means of the inductive or electromagnetic coupling.
The device for sensing respiration of a person in accordance with
The sensor 30, or the receiving device 30, comprises a secondary coil 310 as well as adaptation, impedance conversion and demodulation electronics 320. For example, the turns of the secondary coil 310 are woven into the safety belt 130 or are applied on a carrier film and subsequently glued or welded into the safety belt. The adaptation, impedance conversion and demodulation electronics is advantageously integrated, in immediate proximity to the secondary coil 310, into the safety belt 130, for example in the form of a small plastic enclosure (not depicted in the drawing), which is welded into the safety belt. The receiving device 30 is connected to the evaluation unit (not shown) via a line 161 (see dashed line in the belt) guided along the belt 130. For example, the line 161 may be directly woven into the safety belt, or it may be attached in the form of flat and thin wires along the safety belt. This line 161 extends from the receiving device 30 or, in other words, from the secondary coil 310 comprising the adaptation, impedance conversion and demodulation electronics 320, up to the bracing of the belt on the opposite side. Alternatively, the line 161 may be guided in the other direction along the safety belt up to the belt retractor 136. Both variants are possible from a technical point of view. However, the first variant is technically easier to implement. The line 161 ends with the connection 162 for tapping the sensor signal.
An embodiment of a measuring device 30 is depicted schematically at the bottom of
a shows a further embodiment of a device for monitoring the breathing rate of a person situated in an automobile, the measuring unit 30 being wirelessly coupled to the evaluation unit.
In this embodiment, the receiving or measuring device 30 additionally comprises the functions of data processing and wireless data communication, and it may be directly attached on the safety belt 130, for example in the form of an electronic data processing module in a small housing 602 (see
Therefore, in these embodiments, no further line from the receiving device 300 to the belt bracing or the belt retractor is necessary. The voltage generation module 764 may be selected to supply the entire electronic circuit of the receiving device 300 with power. In the event that the power consumption of the radio unit 762 exceeds the capacity of the voltage generation module 764, a back-up battery 766 may optionally be provided which may be replaced at any time via a battery compartment lid 768. The back-up battery may also be charged on the fly from the surrounding field using an integrated charging circuit, e.g. by means of a specific mode which is active whenever no measurements are conducted and, therefore, whenever the electronics make do with less energy.
What follows is a description of a further embodiment of a device for monitoring the breathing rate of a person situated in an automobile, wherein data communication is effected by means of a feedback of the secondary coil to the primary coil by means of load modulation.
The transmitter device, or the active transmitter, 810 see the top of
The receiving device or measuring device 800, see the bottom of
Further embodiments of the device for sensing respiration, e.g. for monitoring the breathing rate, of a person placed in a functional bed or on an operating table will be described below.
The top of
The embodiment depicted at the bottom of
However, it shall be noted that other data transmission techniques, such as other wireless or wired transmission technologies as have also been set forth above by way of example, may also be employed.
In other words, embodiments of
It may therefore be stated in summary that embodiments of the present invention realize a “device and method for measuring respiration activity”, further embodiments realize a “device and method for measuring respiration activity by means of loosely inductively coupled coils”, and, yet further embodiments realize a “device and method for measuring respiration activity, breathing rate, breathing amplitude and breathing volume by means of loosely inductively coupled coils”.
Embodiments of the present invention additionally relate to a method and a device for measuring respiration activity which comprise a transmitter device and a receiving device, wherein the receiving device is based on a change in the distance between the transmitter unit and the receiver unit and may therefore be sensed using metrological means. The measurement signals within the receiver may be caused by different physical mutual influences between the transmitter unit and the receiver unit.
Variants of these embodiments further comprise a device and a method for sensing the breathing movements in the torso of a living being by means of inductively coupled coils, breathing movements being recognizable, in the form of positional deviations of the secondary coil relative to the primary coil, in that they cause changes in the induced voltage in the secondary coil.
Further ones of the above-mentioned embodiments provide a device and a method for sensing respiration activity, the breathing rate, the breathing amplitude, and the breathing volume by means of the breathing movements which may be detected in the torso of a living being in the form of positional deviations of the secondary coil from the primary coil.
Further variants of the previously mentioned embodiments relate to a measuring device for sensing the breathing movements in the torso of a living being by means of inductively coupled coils.
Yet further variants of the previously mentioned embodiments of the device provide a measuring device for sensing the breathing movements in the torso of a living being by means of inductively coupled coils (primary coil and secondary coil), the measuring system being equipped with additional measuring coils for stabilizing purposes or for measuring interference effects or for measuring amplitude fluctuations, or in other words, the primary coil system and the secondary coil system comprising additional measuring coils.
Further embodiments of the device provide a measuring system, integrated into the seat and into the safety belt, for sensing respiration activity as a continuous signal. In this context, respiration activity may be measured at at least one, but also at several body parts. To this end, the transmitting and receiving devices are implemented a number of times.
In an alternative variant of the above-mentioned embodiment, a measuring system for sensing respiration activity, which is integrated into a functional bed or an operating table, is provided as a continuous signal. Again, respiration activity may be measured at at least one, but also at several body parts; in the latter case, the transmitting and receiving devices are implemented a number of times.
In a further embodiment, the invention provides a medical system for monitoring the vital parameters of a living being, in particular respiration activity, the breathing rate, the breathing amplitude, and the breathing volume.
Further embodiments of the present invention provide a driver assistance system for medical monitoring of the driver's state of health, in particular respiration activity, the breathing rate, the breathing amplitude, and the breathing volume.
Embodiments further provide a measuring system, integrated into the seat and the safety belt, for sensing respiration activity as a continuous signal.
Further embodiments may also be mounted or integrated in other means or devices.
Instead of inductive coupling, further embodiments comprise electromagnetic coupling between the active transmitter and the sensor. The active transmitter 10 and the sensor 30 may each comprise at least one dipole or patch antenna 230, 310, and be electromagnetically coupled to each other, so that the signal provided depends on a change in the field strength in the sensor, said change in the field strength depending on the change in the distance. Instead of the dipole or patch antenna, the active transmitter and/or the sensor may generally comprise antennas for UHF (ultra-high frequency), micrometer or millimeter wave ranges.
In further embodiments, the transponder or the sensor may be attached directly to the body, e.g. in the form of an adhesive plaster, into which the transponder is integrated, and may thus enable measurement even while the body is turning. Due to the direct contact with the patient's body, an improved effect and/or accuracy of the measurement is enabled, and, additionally, personalization is enabled, e.g. with regard to specific standard values or alarm functions for the patient.
In further embodiments, the sensor or transponder may also be integrated into pieces of clothing.
Thus, the invention relates to both a medical system for monitoring the vital parameters of a person, in particular respiration activity, and to a method and a device for sensing the breathing movements in the body of a living being in general, i.e., for example, of human beings, animals, etc.
The field of application of the embodiments of the present invention lies, for example, in the area of preventive, monitoring and back-up medicine. Direct application is possible, for example, in sensing respiration activity in somnology, sports medicine and home care (monitoring the patient in their homely environment).
Depending on the circumstances, the embodiments of the inventive methods may be implemented in hardware or in software. The implementation may be effected on a digital storage medium, in particular a disc, CD or DVD having electronically readable control signals which cooperate with a programmable computer system such that one of the embodiments of the inventive methods is performed. Generally, the embodiments of the present invention therefore also consist in software program products or computer program products or program products having a program code, stored on a machine-readable carrier, for performing one of the embodiments of the inventive methods, when one of the software program products runs on a computer or on a processor. In other words, an embodiment of the present invention may therefore also be realized as a computer program or software program or program having a program code for performing an embodiment of an inventive method, when the program runs on a processor.
In this context, the processor may be constituted by a computer, a chip card, a digital signal processor, or any other integrated circuit.
While this invention has been described in terms of several 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.
Number | Date | Country | Kind |
---|---|---|---|
102008050640.0 | Oct 2008 | DE | national |
102008056252.1 | Nov 2008 | DE | national |