WEARABLE BIO-ELECTROMAGNETIC SENSOR AND METHOD OF MEASURING PHYSIOLOGICAL PARAMETERS OF A BODY TISSUE
20230172473 · 2023-06-08
Inventors
- Jaan Ojarand (Tallinn, EE)
- Mart Min (Tallinn, EE)
- Olev Märtens (Tallinn, EE)
- Raul LAND (Tallinn, EE)
- Eiko PRIIDEL (Tallinn, EE)
- Paul ANNUS (Tallinn, EE)
Cpc classification
A61B5/053
HUMAN NECESSITIES
A61B5/08
HUMAN NECESSITIES
A61B5/02
HUMAN NECESSITIES
A61B5/05
HUMAN NECESSITIES
A61B5/0205
HUMAN NECESSITIES
International classification
A61B5/05
HUMAN NECESSITIES
A61B5/08
HUMAN NECESSITIES
A61B5/02
HUMAN NECESSITIES
Abstract
A wearable bio-electromagnetic sensor comprises an electronic unit containing a means for generating electrical current, and an electromagnetic interface for transforming the generated electrical current into an electromagnetic field applied to a vascularized body tissue. Next, the wearable bio-electromagnetic sensor contains a means for analog signal processing an electrical response of cardiopulmonary system to the applied electromagnetic field. After analog processing of said electrical response, a digital post-processing of digitized electrical response takes place in a means for digital signal processing, embedded into said electronic unit of the wearable bio-electromagnetic sensor. As a result of analog and digital signal processing, an information is extracted, which makes possible medical diagnosing of both, pulmonary and cardiovascular system, separately or simultaneously. The used work principle is following: the applied electromagnetic field induces electrical current inside the body tissue, electrical impedance to which changes correspondingly to breathing and heart beating. Said electrical impedance of varies during every breathing cycle correspondingly to oxygen transporting through arteries and oxygen uptake by capillaries, also due to biomechanical enlargement and narrowing of arteries correspondingly to blood pressure variations.
Claims
1-39. (canceled)
40. A method for determining physiological parameters, the method comprising the steps of: placing an electromagnet with a toroidal core, having a transversely wound winding on said toroidal core, on a convex body part so that the shape of the toroidal core follows ⅛ to 1/1 extent the convex surface of the body part, inducing an alternating electric current in said body organ, galvanically or electromagnetically receiving a response signal from said body organ, and determining said physiological parameters of the body from said response signal.
41. The method according to claim 40, wherein said body organ is a blood vessel and lung function parameters are determined from the response signal.
42. The method according to 40, wherein said body organ is a blood vessel and heart function parameters are determined from the response signal.
43. The method according to claims 40, wherein said body organ is a blood vessel and vascular function is determined from the response signal.
44. The method according to claim 40, wherein two capacitive or galvanic electrodes are placed on each side of the toroidal core of said electromagnet and are connected to close an intracorporal circuit path.
45. The method according to claim 44, wherein said two electrically connected electrodes are used to disconnect certain anatomical parts from the intracorporeal circuit path by shorting the electrodes.
46. The method according to claim 45, wherein the two electrodes are electrically connected to each other via a short-circuit ammeter or an electronic circuit operating equivalent thereto such as a current-voltage converter, for measuring the current of the response signal.
47. The method according to claim 46, wherein the current of the response signal is measured by a toroidal core current transformer.
48. The method according to claim 45, wherein belts arranged around the body are used to close the intracorporal circuit pat
49. The method according to claim 45, wherein the intracorporal circuit is closed through an electrically conductive device.
50. The method according to claim 49, wherein said electrically conductive device is selecting from the group consisting of a sports aid, ski poles, walking poles, a bicycle handlebar, a motorcycle handlebar, a handle for a training equipment or a rehabilitation equipment, and a steering wheel for a vehicle.
51. The method according to claim 49, wherein the intracorporeal circuit path is closed through an electrically conductive device integrated into a garment.
52. The method according to claim 40, wherein the circuit path is closed by a connecting device through which the connection between the hands is made capacitively, magnetically, optically or via a near electromagnetic field.
53. A sensor device for determining physiological parameters of an individual, the device comprising: a toroidal magnetic coil, comprising a circular core with a spiral primary winding wound around it, wherein said circular core is adapted to be placed around a convex shaped body part; an electronic unit, comprising means for generating an electrical input current into said spiral primary winding, thereby generating an electromagnetic field in said convex shaped body part, said electromagnetic field being in the direction of a body organ located inside said convex shaped body part and thereby generating corresponding current in said body organ; means for receiving a response signal from said convex shaped body part; means for calculating physiological parameters from said response signal and said input current, said physiological parameters selected from a group consisting of lung function parameters, heart function parameters and vascular function parameters.
54. The sensor device as in claim 53, comprising a first electrode to be placed on said convex shaped body part on first side of the circular core and a second electrode to be placed said convex shaped body part on opposite side of the circular core, wherein said first electrode and said second electrode are connected with each other through a wire.
55. The sensor device as in claim 54, wherein said first electrode and said second electrode are non-invasive electrodes.
56. The sensor device as in claim 55, wherein said first electrode and said second electrode are capacitive electrodes.
57. The sensor device as in claim 52, comprising a solenoidal secondary winding wound along said circular core, and means for generating a second electrical input into said solenoidal secondary winding.
58. The sensor device as in claim 52, wherein at least part of the circular core is made of a flexible magnetic material, wherein said magnetic material is 1/10 to ½ of the full extent of the circular core.
59. The sensor device as in claim 52, comprising means for connecting an intracorporal circuit, said means selected from a group consisting of a sports aid, ski poles, walking poles, a bicycle handlebar, a motorcycle handlebar, a handle for a training equipment or a handle for a-rehabilitation equipment, a steering wheel for a vehicle, a belt and an electrically conductive material integrated into a garment.
Description
SHORT DESCRIPTION OF FIGURES
[0023] The invention is now described with reference to enclosed illustrative drawings and photographs.
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DETAILED DESCRIPTION OF THE INVENTION
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[0052] The acquired waveform of breathing satisfies the best expectations, but heart-beating response in composite waveform is relatively low and contains disturbances.
[0053] To overcome the problems, a sensor shown in
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[0076] Electrical current can only flow in a closed circuit. Although the human bloodstream is a closed system through the arterial and venous blood vessels, it is difficult to induce a flow throughout the whole body. One solution is to artificially close the circulatory system in the section of interest, for example with additional electrodes, leaving the rest part out of effect, see
[0077] An alternative circuit closure is shown in
[0078] Another alternative way of closing the circuit is shown in
[0079] A third alternative way of closing the circuit is shown in
[0080] A fourth alternative circuit closure is shown in
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[0084] Electrically connected electrodes can also be used to cut off the effects of certain anatomical parts from a closed circuit by shorting the electrodes mounted on them.
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ELEMENT LIST
[0086] Body tissue 1
Strip 2
[0087] Electronic unit 3
Spiral winding (Coil) 4
Electromagnetic interface 5
Means for generating electrical current voltage (digital-to-analog converter DAC) 6
Means for analog signal processing 7
Means for digital signal processing 8
Means for digital data communications 9
Solenoidal winding 10
Capacitance 11
[0088] Loss resistance 12
Analog-to-digital converter ADC 13
Master clock 14
Battery 15
Antenna 16
REFERENCES
[0089] 1. Jian Sun et al. (2018). An Experimental Study of Pulse Wave Measurements With Magnetic Induction Phase Shift Method, Tech Health Care, 2018; 26 (S1):157-167. doi:10.3233/THC-174526.2.
[0090] 2. Jaan Ojarand, Siim Pille, Mart Min, Raul Land. Magnetic Induction Sensor for the Respiration Monitoring (2015), 10th International Conference in Bioelectromagnetism, 16-18 Jun. 2015 in Tallinn, Estonia.
[0091] 3. Sharon Worcester (Apr. 6, 2020). Is Protocol-Driven COVID-19 Ventilation Doing More Harm Than Good? https://www.medscape.com/viewarticle/928236_print 1/2
CLAUSES
[0092] 1. A wearable bio-electromagnetic sensor comprising: an electronic unit, containing means for generating electrical current, means for analog signal processing, means for digital signal processing, and means for digital communications, and an electromagnetic interface for transforming said electrical current into an electromagnetic field applied to a body tissue.
[0093] 2. The wearable bio-electromagnetic sensor according to clause 1, wherein said means for generating electrical current in said electronic unit applies a digital waveform synthesizer embedded into said means for digital signal processing by 15 converting said synthesized digital waveform into said electrical current by the aid of a digital-to-analog converter (DAC).
[0094] 3. The wearable bio-electromagnetic sensor according to clause 1, wherein said electromagnetic interface for transforming said electrical current into an electromagnetic field exploits a magnetic component of the electromagnetic field applied to induce an electrical response in said body tissue.
[0095] 4. The wearable bio-electromagnetic sensor according to clause 1, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field exploits an electric component of the electromagnetic field applied to induce said electrical response in said body tissue.
[0096] 5. The wearable bio-electromagnetic sensor according to clause 1, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field, which exploits as magnetic component as well as the electric component of the electromagnetic field both applied to induce said electrical response in said body tissue.
[0097] 6. The wearable bio-electromagnetic sensor according to clauses 1 and 3, wherein said electromagnetic interface for transforming said electrical current into an electromagnetic field applied to a body tissue comprises an inductive magnetic coil for inducing said electrical response in said body tissue.
[0098] 7. The wearable bio-electromagnetic sensor according to clauses 1, 3 and 6, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue comprises said inductive magnetic coil and a capacitive component forming a resonant circuit for inducing said electrical response in said body tissue.
[0099] 8. The wearable bio-electromagnetic sensor according to clauses 1 and clauses 4, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue comprises capacitive electrodes for inducing said electrical response in said body tissue.
[0100] 9. The wearable bio-electromagnetic sensor according to f clauses 1, 4 and 8, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue comprises said capacitive electrodes and an inductive component to form a resonant circuit for inducing said electrical response in said body tissue.
[0101] 10. The wearable bio-electromagnetic sensor according to clauses 1 and 5, wherein said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue comprises said inductive magnetic coil and said capacitive electrodes forming a resonant circuit for inducing said electrical response in said body tissue.
[0102] 11. The wearable bio-electromagnetic sensor according to clauses 1, 6, 7 and 10, wherein said inductive magnetic coil is wound as a spiral winding on a circular core.
[0103] 12. The wearable bio-electromagnetic sensor according to clauses 1, 6, 7, and 10, wherein said inductive magnetic coil is wound as a circular winding on a circular core.
[0104] 13. The wearable bio-electromagnetic sensor according to anyone of clauses 1, 11 and 12, wherein said circular core is a closed loop of magnetic material.
[0105] 14. The wearable bio-electromagnetic sensor according to clauses 1, 11, 12 and 13, wherein said circular core is a closed loop of magnetic material having one or more discontinuities as a gaps of air and other non-magnetic materials.
[0106] 15. The wearable bio-electromagnetic sensor according to clauses 1, 11 and 12, wherein said circular core is a loop of non-magnetic material.
[0107] 16. The wearable bio-electromagnetic sensor according to clauses 1, 11, 12, 13, 14, and 15, wherein a form of said circular core is modified to fit to round shape body parts on which said wearable bio-electromagnetic sensor is placed
[0108] 17. The wearable bio-electromagnetic sensor according to clauses 1, 8, 9 and 10, wherein said capacitive electrodes have a circular shape.
[0109] 18. The wearable bio-electromagnetic sensor according to clauses 1, 8, 9, and 10, wherein said capacitive electrodes have a semi-circular shape.
[0110] 19. The wearable bio-electromagnetic sensor according to clauses 1 and 11, wherein said capacitive electrodes have a circular form with discontinuities modified to fit to round shape body parts on which said wearable bio-electromagnetic sensor is placed.
[0111] 20. The wearable bio-electromagnetic sensor according to clauses 1, 3, 4, and 5, wherein said means for processing analog signals in electronic unit contains a detector of variations in electrical response to said electromagnetic field applied to said body tissue.
[0112] 21. The wearable bio-electromagnetic sensor according to clauses 1, 3, 4, and 5, wherein said means for processing analog signals in electronic unit contains a detector of level variations in said electrical response to said electromagnetic field 5 applied to said body tissue.
[0113] 22. The wearable bio-electromagnetic sensor according to clauses 1, 3, 4 and 25, wherein said means for processing analog signals in electronic unit contains a synchronous detector of level variations in electrical response to said electromagnetic field applied to said body tissue.
[0114] 23. A work of said synchronous detector of level variations in clause 22 is controlled synchronously with a frequency of said electromagnetic field applied to said body tissue.
[0115] 24. A work of said detector of level variations in clauses 21 and 22, operates at a frequency, detuned 0.1 to 10% from said resonant frequency of electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue.
[0116] 25. The wearable bio-electromagnetic sensor according to clauses 1, 21, 22 and 23, wherein said detectors of level variations in said electrical response to said electromagnetic field applied to said body tissue, in which said variations express electrical energy losses due to variations of electrical conductivity σ(t).
[0117] 26. The wearable bio-electromagnetic sensor according to clauses 21, 22, and 23, wherein said level variations in said electrical response to said electromagnetic field applied to said body tissue express electrical energy losses due to variations of electrical conductivity σ(t) are caused by pulsation of blood amount and 30 pressure in said body tissue accordingly to heart beating.
[0118] 27. The wearable bio-electromagnetic sensor according to clauses 1, 3, 4, and 5, wherein said means for processing analog signals in electronic unit contains a detector of phase shift variations between said electric response and said electromagnetic field applied to said body tissue.
[0119] 28. The wearable bio-electromagnetic sensor according to clauses 1, 3, 4 and 5, wherein said means for processing analog signals in electronic unit contains a detector of real and imaginary parts of complex variations between said electric response and said electromagnetic field applied to said body tissue.
[0120] 29. The wearable bio-electromagnetic sensor according to clauses 1, 7, 9 and 10, 10 wherein said means for processing analog signals in said electronic unit contains a detector of resonant frequency variations of said resonant circuit in said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue.
[0121] 30. The wearable bio-electromagnetic sensor according to clauses 1, 7, 9, 10 and 29, wherein said means for processing analog signals in said electronic unit contains a detector of phase shift due to resonant frequency variations of said resonant circuit in said electromagnetic interface for transforming the electrical current into an electromagnetic field applied to a body tissue.
[0122] 31. The wearable bio-electromagnetic sensor according to clauses 1, 26, 27, 28 and 29, wherein said phase and frequency and real and imaginary parts variations in said electrical response to said electromagnetic field applied to said body tissue express variations of electrical permittivity electrical permittivity ε(t) due to oxygenation of said body tissue accordingly to breathing of lungs.
[0123] 32. The wearable bio-electromagnetic sensor according to clauses 1 and 19, wherein said means for processing analog signals in electronic unit contains a detector of variations in electrical response to said electromagnetic field applied to said body tissue express variations of magnetic permeability μ(t) accordingly to blood flow.
[0124] 33. The wearable bio-electromagnetic sensor according to clause 1, wherein said means for processing analog signals includes a compensator of a permanent part (carrier component) of said electric response to said electromagnetic field applied to body tissue.
[0125] 34. The wearable bio-electromagnetic sensor according to clause 1, wherein said means for processing analog signals includes a bridge circuit for minimizing (zero immersion) said permanent part of said electric response to said electromagnetic field applied to body tissue.
[0126] 35. The wearable bio-electromagnetic sensor according to clause 1, an analog output of said means for processing analog signals in said electronic unit is converted into a digital input of said means for digital signal processing by an analog-to-digital converter (ADC).
[0127] 36. The wearable bio-electromagnetic sensor according to 1, in which said means for digital signal processing in said electronic unit provides a post-processing of digitized output of said means for processing analog signals performing filtering, linearization, post-detection, error minimization, uncertainty reduction, extraction of essential parameters and other required mathematical and logical operations.
[0128] 37. The wearable bio-electromagnetic sensor according to clauses 1 and 2, in which said means for digital signal processing in said electronic unit provides said digital synthesis of said digital waveform for the converting it into said electrical current by the aid of said digital-to-analog converter (DAC).
[0129] 38. The wearable bio-electromagnetic sensor according to clause 1, in which said means for digital signal processing in said electronic unit provides a coding of said extracted essential parameters into a suitable format for a means for digital data communications via included transceiver and antenna.
[0130] 39. The wearable bio-electromagnetic sensor according to clause 1, in which said electronic unit comprises a master clock, which synchronizes the work of said components in it.
[0131] 40. A device for determining physiological parameters of a body organ in a convex body, the device comprising a toroidal core electromagnet shaped to follow the convex surface of the body ⅛ to 1/1 of the convex surface, an alternating current generator, and a means for measuring and processing a response signal.
[0132] 41. The device of clause, wherein the core of the toroidal core electromagnet is a helically wound coil connected to an alternating current generator.
[0133] 42. The device according to clauses 40 to 41, comprising means for closing the path of current induced by an electromagnet and passing through the body.
[0134] 43. The device according to clause 42, wherein the means is an electrically conductive component connecting the two hands.
[0135] 44. The device of clause 43, wherein the device is a metal object.
[0136] 45. The device of clauses 40 to 42, wherein the device is an electrically conductive component connecting the arm and the body.
[0137] 46. The device of clauses 42 to 45, wherein the device is a belt around the body or round body portion.
[0138] 47. The device of clauses 40 to 46, wherein the means for measuring and processing the response signal comprises a current transformer for measuring the response signal.
[0139] 48. The device of clauses 40 to 47, comprising electrodes for measuring the response signal.
[0140] 49. The device of clauses 40 to 47, comprising an ammeter for measuring a response signal in the form of an electric current.
[0141] 50. The device of clauses 40 to 48, comprising a voltmeter for measuring a response signal in the form of an electrical voltage.
[0142] 51. The device of clauses 40 to 49, wherein the means for measuring and processing the response signal comprises an electronic device for obtaining physiological parameters from the results of measuring the induced current and the response signal.