Biophysical sensing systems and methods using non-contact electric field detectors

• US 10,531,805 B2
• Filed: 09/29/2017
• Issued: 01/14/2020
• Est. Priority Date: 09/30/2016
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Bickford, James A., Kratchman, Louis, Freeman, Daniel, Mariano, Laura Jane
• Primary Examiner(s): Le, Thang X
• Application Number:
  US15/720,583
• Publication Number:
  US 20180092557A1
• Time in Patent Office: 837 Days
• CPC Class Codes: A61B 2562/0204 Acoustic sensors
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/02141 Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits A61B5/02233, A61B5/0235 take precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/0536 Impedance imaging, e.g. by tomography
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/291 for electroencephalography [EEG]
• CPC Class Codes: A61B 5/375 using biofeedback

Abstract

Aspects are generally directed to systems and methods that integrate contactless electric field detectors to measure biophysical signals generated by a body. In one example, a biophysical sensing system includes a sensing assembly including an array of contactless electric field detectors, each of the contactless electric field detectors being configured to sense a corresponding component of an electric field generated by a body, a control system to receive sensor data indicative of the components of the electric field sensed by each of the contactless electric field detectors, the control system being configured to generate an estimate of the electric field based on the sensor data, and a feedback system coupled to at least the control system, the feedback system including at least one feedback interface, the feedback system being configured to operate the feedback interface to provide feedback based on the estimate of the electric field.

Claims

1. A biophysical sensing system comprising:

a sensing assembly including an array of contactless electric field detectors, each of the contactless electric field detectors being a microelectromechanical system (MEMS) electric field detector including at least a proof mass configured to sense a corresponding vector component of an electric field generated by a body of a subject based on a displacement of the proof mass;

a control system coupled to the sensing assembly to receive sensor data indicative of the vector components of the electric field sensed by each of the contactless electric field detectors, the control system being configured to generate an estimate of the electric field based at least in part on the sensor data; and

a feedback system coupled to at least the control system, the feedback system including at least one feedback interface, the feedback system being configured to operate the feedback interface to provide feedback to the subject based on the estimate of the electric field.

2. The biophysical sensing system of claim 1, wherein the feedback interface is at least one of a visual display, a speaker, a haptic transducer, a heating or cooling source, and a chemical source.

3. The biophysical sensing system of claim 2, wherein the feedback system includes a housing configured to attach to the subject, the at least one of the visual display, the speaker, the haptic transducer, the heating or cooling source, and the chemical source being coupled to the housing.

4. The biophysical sensing system of claim 3, wherein the feedback is at least one of a series of visual images from the visual display, an auditory feedback from the speaker, a vibration or pressure sensation from the haptic transducer, a heat stimuli or a cooling stimuli from the heating or cooling source, and a chemical stimulus from the chemical source.

5. The biophysical sensing system of claim 1, wherein the control system is configured to compare the estimate of the electric field to an electric field template of a mental state, and instruct the feedback system to operate the feedback interface to induce a neural response in the subject based on a difference between the estimate of the electric field and the electric field template of the mental state.

6. The biophysical sensing system of claim 5, wherein the neural response includes one or more neural oscillations, the feedback system being configured operate the feedback interface to suppress or augment the one or more neural oscillations.

7. The biophysical sensing system of claim 5, wherein the neural response includes an evoked potential, the feedback system being configured operate the feedback interface to modify the evoked potential.

8. The biophysical sensing system of claim 1, wherein the control system is configured to compare the estimate of the electric field to an electric field template of a mental state, and the feedback system is configured to operate feedback interface to match a subsequent estimate of the electric field to the electric field template of the mental state.

9. The biophysical sensing system of claim 1, wherein the feedback interface includes at least one active stimulator, the feedback system being configured to operate the active stimulator to provide a stimulus to the subject based at least in part on the estimate of the electric field.

10. The biophysical sensing system of claim 1, wherein the control system is further configured to generate an input for a human-machine interface based at least in part on the estimate of the electric field.

11. The biophysical sensing system of claim 1, wherein the contactless electric field detectors are positioned to measure electrical activity of the subject'"'"'s heart.

12. A biophysical sensing assembly comprising:

an array of contactless electric field detectors, each of the contactless electric field detectors being a microelectromechanical system (MEMS) electric field detector including at least a proof mass, each of contactless electric field detectors being configured to sense a corresponding component of an electric field generated by a body of a subject based on a displacement of the proof mass;

control electronics electrically coupled to each of the contactless electric field detectors, the control electronics configured to provide sensor data based on the corresponding components of the electric field;

an electromagnetic shield interposed between the array of contactless electric field detectors and the control electronics, the electromagnetic shield being positioned to electromagnetically isolate at least the array of contactless electric field detectors from electromagnetic interference from the control electronics; and

a housing positioned to enclose at least the array of contactless electric field detectors, the control electronics, and the electromagnetic shield, and to suspend the array of contactless electric field detectors relative to the subject.

13. The biophysical sensing assembly of claim 12, wherein the housing is a headpiece.

14. The biophysical sensing assembly of claim 13, wherein the electromagnetic shield is a Faraday cage.

15. The biophysical sensing assembly of claim 12, wherein the control electronics include at least one auxiliary sensor positioned proximate at least one contactless electric field detector of the array of contactless electric field detectors to detect a source of noise in the sensor data.

16. The biophysical sensing assembly of claim 15, wherein the auxiliary sensor includes at least one of an additional electric field detector positioned to sense an external electric field, an inertial sensor positioned to sense movement of the subject, and a physiological sensor to sense a physiological characteristic of the subject.

17. The biophysical sensing assembly of claim 12, wherein the contactless electric field detectors are positioned to measure electrical activity of the subject'"'"'s heart.

18. A biophysical feedback method, the method comprising:

sensing components of an electric field generated by a body of a subject at each of an array of contactless electric field detectors positioned proximate the subject;

receiving sensor data from the array of contactless electric field detectors at a control system, the sensor data indicative of the components of the electric field sensed by each of the contactless electric field detectors of the array of contactless electric field detectors;

generating, at the control system, an estimate of the electric field based at least in part on the sensor data;

comparing the estimate of the electric field to an electric field template of a mental state;

operating at least one feedback interface of a feedback system to provide feedback to the subject based on the estimate of the electric field; and

controlling the feedback interface to induce a neural response in the subject based on a difference between the estimate of the electric field and the electric field template of the mental state.

19. The biophysical feedback method of claim 18, further comprising controlling the feedback interface to match a subsequent estimate of the electric field to the electric field template of the mental state.

20. The biophysical feedback method of claim 18, wherein the neural response includes one or more neural oscillations, and operating the at least one feedback interface includes at least one of displaying a series of visual images on a visual display, radiating auditory feedback from a speaker, generating a vibration or pressure sensation from a haptic transducer, generating a heat stimuli or a cooling stimuli from a heating or cooling source, and providing a chemical stimulus from a chemical source, to suppress or augment the one or more neural oscillations.

21. The biophysical feedback method of claim 18, wherein the neural response includes an evoked potential, and operating the at least one feedback interface includes displaying a series of visual images on a visual display, radiating auditory feedback from a speaker, generating a vibration or pressure sensation from a haptic transducer, generating a heat stimuli or a cooling stimuli from a heating or cooling source, and providing a chemical stimulus from a chemical source, to modify the evoked potential.

22. The biophysical feedback method of claim 18, further comprising generating an input for a human-machine interface based at least in part on the estimate of the electric field.