Wearable device for bioelectrical interaction with motion artifact correction means

• US 20060149146A1
• Filed: 12/08/2003
• Published: 07/06/2006
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Schmidt, Ralf, Reichinger, Christian, Perkuhn, Michael, Such, Olaf, Reiter, Harald, Lauter, Josef, Montvay, Andras
• Granted Patent: US 7,395,105 B2
• Time in Patent Office: Days
• US Class Current: 600/372
• CPC Class Codes: A61B 2562/02 Details of sensors specially adapted for in-vivo measurements
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/02444 Details of sensor A61B5/02427 takes precedence
• CPC Class Codes: A61B 5/25 Bioelectric electrodes therefor
• CPC Class Codes: A61B 5/256 Wearable electrodes, e.g. having straps or bands
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure

Abstract

The invention relates to a wearable device arranged for enabling a bioelectrical interaction with an individual when being brought into contact with the individual'"'"'s skin I, said device comprising electrodes 2 arranged to carry out said interaction by means of a first electrical signal, said electrodes comprise motion artifact detection means 4. The electrode assembly 1 comprises the electrode 2 arranged to carry out a bioelectrical interaction with the individual by means of measuring an electrical signal on the body of the individual I and/or applying an electrical signal to the body of the individual. In order to enable said bioelectrical interaction the electrode 2 is provided with an electrical cable 2a. According to the invention, the electrode 2 is arranged with a pressure sensor 4. The pressure sensor 4 is arranged to measure a normal force component of an external force applied to the electrode due to movement of the individual. Preferably the pressure sensor 4 is a force/pressure sensitive resistor or a capacitive pressure sensor. The pressure sensor is arranged to produce an electrical signal, referred to as the second signal, the magnitude of the second signal being proportional to the pressure load. The pressure sensor 4 is arranged with cables 4a, 4b for purposes of signal processing.

Claims

1. A wearable device (30) arranged for enabling a bioelectrical interaction (M,S) with an individual by means of a first signal (S), said device comprising an electrode (2) having a contact surface arranged to be brought into contact with the individual'"'"'s skin (I) for carrying out said interaction, the electrode comprising motion artifact detection means (4), characterized in that the motion artifact detection means (4) is arranged to determine a component normal to the contact surface of an external force applied to the electrode under operating conditions, said motion artifact detection means being arranged to provide a second signal (M) and comprising motion artifact correction means (20) to process the second signal in order to correct the value of the first signal for a motion artifact.

2. A wearable device according to claim 1, characterized in that the device comprises control means (16) arranged to analyze the second signal (M), said control means (16) being further arranged to actuate the motion artifact correction means (20) upon an occurrence of a predetermined event.

3. A wearable device according to claim 2, characterized in that the device comprises means for deriving the occurrence of the predetermined event from the second signal.

4. A wearable device according to claim 1, characterized in that the motion artifact detection means (1a) comprises a pressure sensor (4) arranged on a rear surface of the electrode (2), said rear surface being opposite the contact surface.

5. A wearable device according to claim 4, characterized in that the pressure sensor (4) comprises a thin film.

6. A wearable device according to claim 1, characterized in that the motion artifact correction means comprises a linearization element, said linearization element being arranged to correct for a non-linearity in a relation between an absolute value of the second signal and the external force.

7. A wearable device according to claim 1, characterized in that the electrodes are of a dry type.

8. An electrode assembly (1) comprising an electrode having a contact surface, the assembly being arranged to enable a bioelectrical interaction with an individual by means of a first signal (S) when the contact surface is brought in contact with the individual'"'"'s skin, said electrode assembly comprising motion artifact detection means (4), characterized in that the motion artifact detection means (4) is arranged to determine a component normal to the contact surface of an external force applied to the electrode under operating conditions, said motion artifact detection means being arranged to provide a second signal (M), related to the external force.

9. An electrode assembly according to claim 8, characterized in that the artifact detection means (4) comprises a pressure sensor arranged on a rear surface of the electrode, said rear surface being opposite the contact surface.

10. An electrode assembly according to claim 9, characterized in that the pressure sensor comprises a thin film.