JP2018502642A - Extended transcutaneous electrical nerve stimulator with automatic detection of leg orientation and movement for extended sleep analysis - Google Patents

Abstract

An apparatus for providing percutaneous electrical nerve stimulation (TENS) therapy to a user, comprising: a housing; a mounting unit for providing a mechanical coupling between the housing and the user's body; and at least one of the user Feedback to the user based on the stimulation unit for electrically stimulating the nerve, the sensing unit for sensing the user's body movement and body direction, and the user's sensed body movement and body direction And a reporting unit for providing a device. [Selection] Figure 4

Description

Reference to earlier pending patent applications
(1) Pending U.S. Patent Application No. 14 / 794,588, filed July 8, 2015 by NeuroMetrix and Xuan Kong et al., “MEASURING THE“ ON-SKIN ”TIME OF A TRANSCUTANEOUS ELECTRICAL NERV. STIMULATOR (TENS) DEVICE IN ORDER TO MINIMIZE SKIN IRRIRATION DUE TO EXCESSIVE UNINTERRUPTED WEARING OF THE SAME "(Attorney reference number NEURO-73)
(A) NeuroMetrix and Shai N. Pending US Patent Application No. 14 / 610,757, filed Jan. 30, 2015 by Gozani et al., “APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION 59” CON), which is a continuation-in-part application,
(I) NeuroMetrix and Shai N. US Patent Application No. 13 / 678,221 filed November 15, 2012 by Gozani et al., “APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION” And this application is
(A) Shai N. Previous US Patent Application No. 61 / 560,029, “SENSUS OPERATING MODEL” (Attorney Docket Number NEURO-59 PROV), filed November 15, 2011 by Gozani, and (b) Shai N. US Patent Provisional Application No. 61 / 657,382, filed June 8, 2012, by Gozani et al., “APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANOUS ELECTRICAL NERVE STIMULATION RO” Claim (1)
(B) Pending U.S. Patent Application No. 14 / 269,887 filed on May 5, 2014 by NeuroMetrix and Thomas Ferrele et al., “TRANSCUTANEOUS ELECTRICAL NEXTULATOR TECHTOR TESTOR GESTRETER DETECTOR, WITH TRANSITION MOTION DETECTOR FOR INCREASING THE ACCURACY OF THE SAME "(Attorney Docket Number NEURO-6667)
(I) Pending US Patent Application No. 14 / 230,648, filed March 31, 2014, by NeuroMetrix and Shai Gozani et al., "DETECTING CUTANEOUS ELECTRODE PEELING USECT ELECTRODE-SKIN IMPEDAN" This is a continuation-in-part application of reference number NEURO-64).
(A) Previous US Provisional Application No. 61 / 806,481, filed March 29, 2013 by Shai Gozani, “DETECTING ELECTRODE PEELING BY RELATIVE CHANGES IN SKIN-ELECTRODE IMPEDANCE” (Attorney Docket Number NEURO) 64 PROV), and (B)
(Ii) Pending U.S. Patent Application No. 14 / 253,628, filed April 15, 2014, by NeuroMetrix and Shai Gozani et al., "TRANSCUTANEOUSE ELECTRICAL STUMULATOR WITE A AUTOMATE TEATER "(Attorney Docket Number NEURO-65), a continuation-in-part application,
(A) Previous US Provisional Application No. 61 / 811,864, filed April 15, 2013 by Shai Gozani, “TRANSCUTANEOUS ELECTRICAL NEXT TIMULATOR WITCH AUTOMATIC OF PATIENT AUTHOR SLEEP No.” NEURO-65 PROV) and (B)
(Iii) Previous US Provisional Application No. 61 / 819,159 filed May 3, 2013 by Neurometrics and Thomas Ferrele et al. Insist on the benefit of (agent number NEURO-66 PROV), (B)
(Iv) Previous US Provisional Application No. 61 / 858,150 filed July 25, 2013 by Neurometrics and Andrews Aquirere et al., “MOVEMENT REGULATION TRIP CONDITIONS IN A WEUALUTE TRANCECTOR (No. NEURO-67 PROV) and claim (1)
(C) Previous US Provisional Application No. 62 / 021,807, filed July 8, 2014 by Neurometrics and Xuan Kong et al., “MEASURING TENS DEVICE ON-SKIN TIME TO PREVENT AND MINIZER SKIN” Claiming the benefit of agent reference number NEURO-73 PROV),
(2) Previous US Patent Provisional Application No. 62 / 213,978, filed on September 3, 2015, by Neurometrics and Thomas Ferrele et al., “TRANSCUTANEOUS ELECTRICAL EDITION OFLION DETECTION OF DETECTION ANALYSIS "(Attorney Docket Number NEURO-77 PROV), and (3) Previous US Provisional Application No. 62 / 101,029," METHOD "filed January 8, 2015 by Neurometrics and Shai Gozani et al. AND APPARATUS FOR USING TRANSCUTANEOUS ELE It claims the benefit of “CTRICAL NERVE STIMULATION TO AID SLEEP” (agent reference number NEURO-69A PROV).

The 15 patent applications described above are hereby incorporated herein by reference.
The present invention relates generally to a transcutaneous electrical nerve stimulation (TENS) device that applies an electrical current across an intact skin of a user via an electrode to reduce pain symptoms. More specifically, the present invention relates to a TENS device worn during sleep and a method for making novel measurements that expand and extend sleep analysis, and an extended process using the device and method. Includes cutaneous electrical nerve stimulation (TENS).

  Chronic pain from diabetic neuropathy and other causes can interfere with sleep, which is accompanied by a number of concurrent complications. Percutaneous electrical nerve stimulation (TENS) devices alleviate pain by stimulating sensory nerves, which results in an increase in endogenous opioids and downward modulation of transmission of pain signals to the brain. TENS devices that can be used during sleep should provide a unique opportunity to alleviate bedtime pain with the goal of improving sleep (eg, Barbarisi M, Pace MC, Passavanti MB et al., “Pregabalin and transcutaneous electrical nerve simulation for positive therapeutic treatment, Clin J Pain, Sep. 2010, 26 (7): 567-572).

  However, most TENS devices are designed to operate exclusively in the daytime (i.e. during wakefulness) rather than during the night (i.e. sleep state). This limitation is evident in conventional TENS device designs where current is applied through wires (called leads) connected to electrode pads on the skin. Such a design can lead to the tampering and tangling or pulling of the lead, and the electrode pads can be peeled off the skin (which will end the TENS treatment), or perhaps worse from the skin. It ’s impractical to use while sleeping, as it can partly increase, resulting in increased current density and negative consequences for the user (for example, discomfort or extreme burns) Or not safe.

  Pending US Patent Application No. 14 / 230,648, filed March 31, 2014, by NeuroMetrix and Shai Gozani et al. -64) was published as US Patent Application Publication No. 2014/0296934 A1 on October 2, 2014, and is hereby incorporated herein by reference, as well as during daytime (ie during wakefulness) A novel TENS device has been disclosed that allows TENS therapy to be applied even at night (ie sleep state). Key design elements that make this novel TENS device suitable for use during sleep include: (1) the electrode pads are attached directly to the housing containing the TENS stimulation circuit, and leads are removed, (2) TENS The housing and electrode pad are securely and comfortably held against the skin by an adjustable strap or band. (3) The TENS device has the electrode pad peeled off (completely or partially) from the skin Continuously measure skin-electrode contact impedance (and associated electrical parameters) to detect whether or not current delivery is stopped when peeling is detected. (4) Treatment stimulus is night May be scheduled with 1 hour on-off block to relieve pain through, (5) TENS device makes the user sleep It detects that there is automatically reduced therapeutic stimulation levels so as not to interfere with sleep, sometimes such.

  The novel TENS device disclosed in pending earlier US patent application Ser. No. 14 / 230,648 (published as US Patent Application Publication No. 2014/0296934 A1) is placed on top of the user's calf. Designed to be There are three reasons for this. First, TENS devices need to stimulate sensory nerve fibers to relieve pain over a wide area due to the systemic effects of increased endogenous opioids and down-regulation of pain signal transmission. There is a mass of sensory nerve fibers in the upper calf region, which is close to the surface of the skin and can be easily activated using a percutaneous electrical nerve stimulator. Secondly, some forms of chronic pain (such as due to diabetic neuropathy) are felt most intensely in the foot and are more localized in addition to the above-described (systemic) pain suppression mechanisms by endogenous opioids. There is also evidence to prove a further mechanism of pain suppression, so it is advantageous to place the TENS device on top of the user's calf. Third, chronic pain can be persistent throughout the day and often worsen at night, but it becomes milder when a TENS device is worn over the calf, which promotes more regular use.

  As noted above, the novel TENS device disclosed in pending US Patent Application No. 14 / 230,648 (published as US Patent Application Publication No. 2014/0296934 A1) can be used during sleep. Designed for use, when the user senses that they are asleep, it adjusts the stimulation level of the therapy so as not to disturb sleep. Quantifying sleep quality and sleep disorders also increases the likelihood of using a TENS device and improving sleep quality if the user is aware and confident of the benefits of a TENS device over their sleep. It would be advantageous for TENS devices aimed at.

  A typical criterion in determining a subject's sleep-wake state is a polysomnogram that includes at least three distinct types of data, such as an electroencephalogram (EEG), an electrooculogram (EOG), and an electromyogram (EMG). Due to the difficulty of recording and analyzing these types of data, sleep-wake determination has been developed and improved over the last 30 years as a practical alternative to investigating sleep / wake patterns. ing. The sleep / wake determination method is generally a continuous recording of body movements by a device worn by the body and equipped with an accelerometer [Ancoli-Israel S, Cole R, Alessi C, Chambers M, Moocroft W , Pollak CP. The role of activity in the study of sleep and ircadian rhytms. Sleep. May 1, 2003, 26 (3), 342-392].

  Wearable electronic devices for health and fitness are widespread and most have accelerometers to track various metrics of activity from acceleration data to track daytime activity or to quantify sleep patterns. calculate. However, most devices based on these sleep awakening methods are worn on the wrist in a specific way, which limits their ability to detect and quantify sleep.

  Placement of TENS devices equipped with accelerometers at the top of the calf with a mechanical connection to the top of the calf is a novel method for detecting when the user is asleep and to analyze the user's sleep Novel metrics and novel techniques for quantifying body and leg movements associated with distress such as poor sleep quality and / or restless leg syndrome, and extended percutaneous electricity It is now well recognized that it can be used to accommodate novel approaches to providing neural stimulation (TENS). Some of these novel metrics can lead to snoring or sleep apnea, as well as “leg movements”, “body rotation events” and rolling pain associated with rolling in bed There is also a “back-up time” that is also associated with problematic sleeping postures. In addition to tracking and reporting sleep metrics, real-time feedback to users based on indicator trends can also help users improve sleep quality. An example may be to alert the user when the supine time exceeds a threshold (eg, by mechanical or electrical means). Another example may be changing the TENS stimulation parameters to extend the analgesic effect of TENS treatment when a pattern of leg movement associated with discomfort caused by night pain is detected.

  Accordingly, the present invention comprises a novel TENS stimulator designed to be placed on the upper part of the user's calf and a pre-configured electrode arrangement designed to stimulate around the upper part of the user's calf. Includes provision and use of TENS devices. A triaxial (x, y, z) accelerometer built into the TENS device projects the static gravity onto each axis (ie, x, y, z) and the user in each axis, depending on the direction of the device The acceleration that changes with time due to the movement of the sensor along its axis is continuously measured.

  The placement of the novel TENS device on the upper part of the user's calf corresponds to a novel method for detecting when the user is sleeping, to quantify sleep and assess abnormal movements of the body and legs, and Used to provide extended TENS therapy using such sleep analysis.

  First, the novel TENS device measures the leg direction, which is highly correlated with the direction of the body and thus indicates the user's recumbency (thus indicating the user's sleep-wake state). Is. Specifically, the novel TENS device has a leg “elevation” (ie, the angle of the lower leg with respect to the horizontal) and a “rotation” of the leg (ie, the angle of rotation of the lower leg about its own axis). Are measured in two separate directions in the leg direction.

  Secondly, the novel TENS device measures leg movement, which also indicates the user's sleep-wake state. Specifically, the novel TENS device has “net activity” (the magnitude of acceleration related to movement averaged over a one-minute time window) and “leg movement” (ie Two distinct aspects of leg movement are measured, such as short events that are known to occur during sleep but are not evident in net activity. Some leg movements with large leg rotations can be further categorized as “body rotation events” (such as those that occur when rolling in bed). People with chronic pain and other medical conditions can experience repeated leg movements that can degrade the quality of sleep felt by the person (and their sleep partner). Repeated leg movement quantification and monitoring can provide insight into these conditions and trends in these conditions.

  Thirdly, the novel TENS device is designed to extend these therapeutic benefits to these two measurements of leg movement (ie net activity and leg movement) and two measurements in the leg direction (ie leg uplift and leg rotation). ) To improve sleep quantification and use more accurate quantification metrics.

  The determination of sleep-wake state by a novel TENS device proceeds in several steps. If the user's leg direction is determined to be lying (ie, close to horizontal) over a selected portion (eg, most) of a selected time period (eg, a time window to determine), Is considered. While sleeping, “sleep onset” is defined as the first time that a user's net activity and leg movement falls below a set threshold over a specified period of time (eg, a time window to determine). . Following sleep onset, the novel TENS device measures net activity and leg movement. Throughout all of the time intervals where the net activity is below some defined threshold, the user is considered “sleeping”. Throughout all the time the user is lying, the net activity is below some net activity threshold, the number of leg movements is below some leg movement threshold, and the number of body rotations Is zero and the user is considered "being comfortable". Throughout all of the time that the static rotation angle of the leg is between the two thresholds of the static rotation angle of the leg, the user is considered to be sleeping “up on the back”. These times and percentages of these times can be used to calculate “sleep time” and “sleep quality” measurements. This sleep analysis may then be reported (eg, to the user and / or the caregiver of the user) and / or used to provide the patient with extended TENS therapy.

In one desirable form of the invention, an apparatus is provided for providing percutaneous electrical nerve stimulation (TENS) therapy to a user, the apparatus comprising:
A housing;
A mounting unit for providing a mechanical coupling between the housing and the user's body;
A stimulation unit for electrically stimulating at least one nerve of the user;
A sensing unit for sensing a user's body movement and body direction;
And a reporting unit for providing feedback to the user based on the user's sensed body movement and body orientation.

In another desirable form of the invention, a method is provided for providing percutaneous electrical nerve stimulation to a user, said method comprising:
Attaching a stimulation unit and a sensing unit to the user's body;
Applying electrical stimulation to the user using the stimulation unit to stimulate one or more nerves;
Analyzing electromechanical sensing data from the sensing unit to quantify a user's body orientation and body activity level;
Changing electrical stimulation applied by the stimulation unit based on the user's body orientation and body activity level.

In another desirable form of the invention, an apparatus is provided for monitoring a user's sleep pattern, the apparatus comprising:
A housing;
A mounting unit for providing a mechanical coupling between the housing and the user's body;
A sensing unit disposed within the housing to sense a user's body movement and body direction;
A reporting unit for providing feedback to the user based on the user's sensed body movement and body direction.

In another desirable form of the invention, a method is provided for monitoring a user's sleep pattern, the method comprising:
Attaching a sensing unit and a feedback unit to the user's body;
Using a sensing unit to determine a user's body movement and body direction;
Providing feedback to the user via the feedback unit based on physical activity and body orientation.

In another desirable form of the invention, an apparatus is provided for providing percutaneous electrical nerve stimulation (TENS) therapy to a user, the apparatus comprising:
A housing;
A mounting unit for providing a mechanical connection between the housing and a user's leg;
A stimulation unit for electrically stimulating at least one nerve of the user;
A sensing unit for sensing a user's leg direction and leg movement, wherein sensing the user's leg direction includes determining a user's leg ridge and leg rotation, and sensing the user's leg movement. A sensing unit comprising determining a user's net activity and leg movement;
And a controller for adjusting the stimulation unit based on the determination by the sensing unit.

  These and other objects and features of the invention will be more fully disclosed or clarified by the following detailed description of preferred embodiments of the invention to be considered in conjunction with the accompanying drawings. In the drawings, the same numbers refer to the same parts.

1 is a schematic diagram illustrating a novel TENS device formed in accordance with the present invention, attached to a user's calf top. FIG. FIG. 2 is a schematic diagram illustrating the novel TENS device of FIG. 1 in more detail. FIG. 3 is a schematic view of the novel TENS device of FIGS. 1 and 2 attached to a patient's tissue. FIG. 3 is a schematic diagram of the novel TENS device of FIGS. 1 and 2 including a detector of user status (ie leg direction and leg movement). The novel TENS device skin surface sensing system shown in FIGS. 1 and 2, and the equivalent circuit when the novel TENS device is on the user's skin, and the novel TENS device is away from the user's skin It is the schematic which shows the equivalent circuit at the time. FIG. 3 is a schematic diagram showing the orientation of the accelerometer incorporated in the novel TENS device of FIGS. 1 and 2 when the novel TENS device of FIG. 1 is attached to the upper calf of a user. Schematic showing the relationship between the gravity vector g in the novel TENS device and the y-axis of the accelerometer when the novel TENS device (attached to the top of the user's calf) is stationary at an elevation angle θ relative to the horizontal plane. FIG. FIG. 6 is a schematic diagram illustrating detection of a leg movement (LM) event and calculation of a change Δφ after the LM event (relative to the event) of the device rotation angle φ. Mathematical processing for associating the rotation angle φ of the accelerometer (measured by the accelerometer) with the leg rotation angle β via a third angle α representing the rotation position of the novel TENS device in the upper part of the user's calf FIG. 2 is a schematic flow diagram illustrating an exemplary operation of a novel TENS device that includes a detector of user status (ie, leg orientation and leg movement).

Overview of Novel TENS Device FIG. 1 shows a novel TENS device 100 formed in accordance with the present invention worn on a user's upper calf 140. A user may wear the TENS device 100 on either leg.

  The TENS device 100 shown in more detail in FIG. 2 preferably includes a stimulator 105, a strap 110, and an electrode arrangement 120 (appropriately suitable for the cathode electrode and the stimulator 105, as is well known in the art). And three main components including a connected anode electrode). The stimulator 105 comprises three compartments 101, 102 and 103, preferably mechanically and electrically interconnected. The compartments 101, 102, 103 are preferably interconnected by a hinge mechanism 104 (only one of which is shown in FIG. 2), whereby the TENS device 100 is attached to the curved tissue of the user's leg. Can adapt. In the preferred embodiment of the present invention, compartment 102 houses TENS stimulation circuitry (except for the battery) and user interface elements 106 and 108. Compartment 102 is preferably an accelerometer 152 (in the form of a semiconductor chip accelerometer) for sensing user gestures, user leg and body orientation, and user leg and body movements, as discussed below. (See FIGS. 4 and 6). Partition 102 also houses a real time clock 505 (FIG. 4). In a preferred embodiment, compartments 101 and 103 include a battery for powering the TENS stimulation circuit and other circuits, an ambient light sensor or detector 510 (FIGS. 4 and 6) for determining ambient light conditions, etc. Other auxiliary elements and types of wireless interface units well known in the art to allow the TENS device 100 to communicate wirelessly with other elements (eg, portable electronic devices such as the smartphone 860). (Not shown) and a smaller auxiliary compartment. In another embodiment of the invention, only one or two compartments may be used to accommodate all of the TENS stimulation circuit, battery, and other auxiliary elements of the invention. In another embodiment of the present invention, many compartments are used, for example to better adapt to the body and improve user comfort. In another embodiment of the invention, a flexible circuit board is used to more evenly distribute the TENS stimulation circuit and other circuits around the leg, thereby reducing the volume.

  Turning now to FIG. 2, the user interface element 106 preferably comprises a push button for the user to control electrical stimulation, and the user interface element 108 is used to indicate the stimulation state and to the user. In order to provide other information, an LED is preferably provided. Additional user interface elements (eg, multiple LED arrays, LCD displays, audible feedback via pager or audio output, haptic devices such as vibration motors) may also be provided and are considered within the scope of the present invention.

  The preferred embodiment of the present invention is designed to be worn on a user's upper calf 140, as shown in FIG. A TENS device 100 comprising a stimulator 105, an electrode array 120, and a strap 110 is securely attached to the upper calf 140 by placing the device in place and then tightening the strap 110.

  Although the preferred embodiment of the present invention places the TENS device on top of the user's calf, additional anatomical locations (such as on the waist, above the knee, and above the upper arm) are also contemplated and within the scope of the present invention. Considered.

  FIG. 3 is a schematic diagram of the current between the TENS device 100 and the user. As seen in FIG. 3, the stimulation current 415 from the constant current source 410 flows through the anode electrode 420 into the user's tissue 430 (eg, the user's upper calf). The anode electrode 420 includes a conductive backing (eg, silver hatched lines) 442 and a hydrogel 444. The current passes through the user's tissue 430 and returns to the constant current source 410 via the cathode electrode 432 (the cathode electrode 432 also comprises a conductive backing 442 and a hydrogel 444). The constant current source 410 preferably provides a suitable biphasic waveform of a type well known in the art of TENS therapy (ie, biphasic stimulation pulses). In this regard, it should be understood that the meanings of the “anode” and “cathode” electrodes are purely notational in the context of a two-phase waveform (ie, the two-phase stimulation pulse, the two-phase When the polarity in the second phase of TENS stimulation is reversed, current will flow through the “cathode” electrode 432 to the user's body and back from the user's body through the “anode” electrode 420).

Further details regarding the construction and use of the foregoing aspects of TENS device 100 can be found in (i) NeuroMetrix and Shai N. on February 3, 2015. U.S. Patent No. 8,948,876 issued to Gozani et al., "APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION" (Attorney Docket Number NEURO-5960) h. Pending US Patent Application No. 14 / 230,648, filed March 31, 2014, by Gozani et al., “DETECTING CUTANEOUS“ ELECTRODE PEELING ”USING ELECTRODE-SKIN IMPEDANCE” (Attorney Docket NEURO-64) ), Published on Oct. 2, 2014 as U.S. Patent Application Publication No. 2014/0296934 A1, which is hereby incorporated herein by reference. Incorporated.
User State (ie Leg Direction and Leg Movement) Detector According to the present invention, the user state (ie leg direction and leg movement) detector 500 that the TENS device 100 further comprises (eg, within the compartment 102) comprises: (i) Providing enhanced transcutaneous electrical nerve stimulation (TENS) to determine a user's sleep-wake state, (ii) analyze the user's sleep, and / or (iii) use the TENS device 100 Is to do. Turning now to FIG. 4, to achieve this goal, the user state (ie, leg direction and leg motion) detector 500 generally includes the accelerometer 152 described above, the real-time clock 505 described above, and the surroundings described above. The stimulation current provided by the light detector 510, the processor 515 for calculating the user's activity (eg, body direction, body movement and level of activity), and the constant current source 410 of the TENS device 100 is processed by the processor 515. And a controller 520 for changing in accordance with the determination by.

  When the TENS device is securely attached in place at the top of the user's calf, the position and orientation of the accelerometer 152 (FIGS. 4 and 6) of the TENS device 100 is fixed relative to the user's lower limb. When the TENS device 100 and the lower limb 140 are firmly mechanically coupled, the movement of the user's lower limb can be accurately measured by the accelerometer 152. Such a tight mechanical connection is preferably established by the strap 110 described above. Alternatively, a tight mechanical connection may be established by other means (eg, a flexible band that wraps the TENS device). If desired, a tensiometer 109 (FIG. 1) may be provided on the strap 110 to confirm that a tight mechanical connection has been established between the TENS device 100 and the calf top 140.

  Data from the accelerometer 152 is analyzed in real time by the processor 515 of the user condition (ie leg direction and leg movement) detector 500 to determine the direction and movement of the user's lower limb (ie upper calf 140). The direction, motion, and activity level of the user's lower limb (ie, upper calf 140) determined by analyzing data from the accelerometer 152 are used to determine the user's sleep-wake state and sleep pattern. . The TENS device 100 changes its stimulation pattern (such as the intensity level of the stimulus and the start of the stimulus) via the controller 520 based on the sleep-wake state and sleep pattern, or additional feedback to the user (the supine state) If the sleep period exceeds a threshold value, mechanical vibration or the like can be supplied.

  The components of leg direction and leg movement measured by the user state (ie leg direction and leg movement) detector 500 of the present invention may contribute to determining the user's sleep-wake state individually or collectively. . In one preferred form of the invention, the processor 515 of the TENS device 100 measures the user's calf direction, which is highly correlated with the user's body direction. More specifically, if the body direction is upright, it is generally a reliable indicator that the user is awake, and the direction of recumbency suggests a resting state (for example, something that occurs during sleep). Regular and steady body movements are likely the result of user activity during the daytime (ie during wakefulness), while quiet or low-level unconscious movements are at night (ie during sleep) There is a high possibility of being. The interaction of body direction and level of motion may also be useful in identifying the user's sleep-wake state (ie, thereby extending the sleep-wake state classification). Specifically, body orientation and low-level physical activity that are lying are generally good indicators that a user is asleep.

  In addition, the user state (ie, leg direction and leg movement) detector 500's real-time clock 505 provides sleep-wake states obtained by the aforementioned analysis of leg direction and leg movement data at any given time of the day. In order to further improve the classification results of the user, it is possible to assign an important a priori probability of sleep-wake state (ie, the user is likely to sleep at 3 am and sleep at 4 pm Less likely). In a preferred embodiment of the present invention, the threshold for classifying a user's body orientation as lying is more stringent to reflect a low a priori probability of sleep during a particular daytime period. obtain.

In another embodiment of the present invention, the output from ambient light sensor 510 is used to improve sleep-wake classification results. Whether the ambient light sensor 510 is illuminated in the user's environment to reflect the a priori probability that a darker setting is more likely to be asleep than a brightly lit setting Can be used to determine Thus, the threshold for classifying the user's posture and exercise level can be adjusted to reflect the a priori probability of sleep.
Skin Surface Detector In one desirable form of the invention, the TENS device 100 may include a skin surface detector to confirm that the TENS device 100 is firmly seated on the user's skin.

More specifically, when the TENS device is worn by the user, the direction and motion measurements from the accelerometer 152 in the TENS device 100 are tied only to the user's direction and motion. In a preferred embodiment, a skin surface detector 521 is provided to determine whether the TENS device 100 is securely placed on the user's upper calf and the time it is placed securely. Turning now to FIG. 5, in a preferred embodiment, the skin surface detector 521 may be provided within the TENS device 100. More particularly, in one desirable form of the invention, closing the switch 220 applies a voltage of 20 volts from the voltage source 204 to the anode terminal 212 of the TENS stimulator 105. When the TENS device is worn by the user, the user tissue 430 placed between the anode electrode 420 and the cathode electrode 432 forms a closed circuit and applies a voltage to the voltage divider circuit formed by resistors 208 and 206. To do. More specifically, when the TENS device 100 is on the user's skin, the equivalent circuit 260 shown in FIG. 5 represents a real system, and the anode voltage V _a 204 can be sensed by the resistors 206 and 208 of the voltage divider. . The cathode voltage measured from the amplifier 207 is not zero and is close to the anode voltage 204. On the other hand, when the TENS device 100 is not on the user's skin, the equivalent circuit 270 represents a real system and the cathode voltage from the amplifier 207 is zero.

The skin surface detector 521 is preferably employed in two ways.
First, when the skin surface detector 521 indicates that the electrode array 120 of the TENS device 100 is partially or completely separated from the user's skin, the TENS device 100 applies TENS therapy to the user. Can be stopped.

Second, when the skin surface detector 521 indicates that the electrode array 120 of the TENS device 100 has been partially or completely separated from the user's skin, the processor 515 of the TENS device 100 may receive data from the accelerometer 152. Will not be a reliable reflection of the user's leg direction and leg movement, and the user state (ie leg direction and leg movement) detector 500 will respond appropriately (eg, alert the user). be able to. In this regard, when the skin surface detector 521 indicates that the TENS device 100 is on the user's skin and the accelerometer 152 is tightly coupled to the user's lower limb, the data from the accelerometer 152 is It should be understood that and may represent a user's leg movement. However, when the skin surface detector 521 indicates that the TENS device 100 is not on the user's skin, and the accelerometer 152 is not tightly coupled to the user's lower limb, the data from the accelerometer 152 is in the user's leg direction and It does not represent the user's leg movement.
Processing of Accelerometer Data In one desirable form of the invention, the user state (ie leg direction and leg movement) detector 500 obtains accelerometer data from the accelerometer 152 to obtain user activity (eg, body direction, A processor 515 for calculating body movement and activity levels.

  More particularly, in one desirable form of the invention, the processor 515 is highly correlated with the body direction and thus indicates the user's recumbency (thus indicating the user's sleep-wake state). The accelerometer data from accelerometer 152 is used to measure the user's leg direction and the user's leg movement, which is also indicative of the user's sleep-wake state and activity level of leg movement, and the user's leg Extending sleep quantification using orientation and user leg movement determinations.

  More particularly, the processor 515 determines the user's “lift” (ie, the angle of the lower leg relative to the horizontal plane) and the “rotation” of the leg (ie, the angle of rotation of the lower leg about its own axis). Accelerometer data from accelerometer 152 is used to measure two distinct aspects of leg direction.

  In addition, the processor 515 determines the “net activity” (the magnitude of acceleration related to movement averaged over a one-minute time window) and the “leg movement” (ie, what happens during sleep). The accelerometer data from accelerometer 152 is used to measure two distinct aspects of leg movement, such as known short-lived events but not evident in net activity. Some leg movements with large leg rotations can be further categorized as “body rotation events” (such as those that occur when rolling in bed).

In a preferred embodiment of the present invention, the processor 515 for calculating user activity (eg, body direction, body movement and level of activity) is constructed and configured to operate as follows. Raw accelerometer data generated at 400 Hz is downsampled to 50 Hz. Thereafter, the “instantaneous” time scale is defined as 0.1 seconds. 10 Hz low noise data expressed as A _x (t), A _y (t), and A _z (t), with 50 Hz data in each axis (x, y, z) averaged separately over each instant Bring the stream.

The accelerometer data A _x (t), A _y (t), and A _z (t) are used for a longer period of time to capture a steady prediction of the Earth's gravity along each axis (x, y, z). Used to form a characteristic that is the average of A _x (t), A _y (t), and A _z (t) over a window (eg, a 1 minute time window). These characteristics are used to detect leg direction (ie leg protuberance and leg rotation).

In addition, the accelerometer data A _x (t), A _y (t), and A _z (t) are subjected to static gravity with a high-pass filter to separate acceleration components caused by leg movement. The component is removed. The -3 dB point of the high pass filter is at 0.5 Hz. The accelerometer data with high-pass filter is

,

,and

It is expressed.
Leg Protrusion Detection In one desirable form of the invention, the user state (ie leg direction and leg motion) detector 500 is configured to detect leg protuberances.

  More particularly, the leg protuberances that the present invention uses to determine “body orientation” for sleep monitoring purposes are detected by the processor 515 of the user status (ie, leg orientation and leg motion) detector 500 by the TENS device. Calculated based on measurement data from the accelerometer 152 when 100 is placed on the user's upper calf 140 (FIG. 1). Turning now to FIG. 6, in a preferred embodiment, the accelerometer 152 is disposed on a circuit board 151 of a TENS circuit housed inside the compartment 102 so that the TENS device is on top of the user's calf. When positioned, the directions of the three axes of the accelerometer shown at 153 in FIG. 6 (ie, the x-axis, y-axis, and z-axis) are known and are fixed relative to the lower leg, and the y-axis Are vertically aligned along the longitudinal axis of the lower leg, the x-axis is arranged in a tangential direction with respect to the surface of the lower leg, and perpendicular to the y-axis, It faces in a radial direction.

  The calf of a user standing upright and standing or seated on the ground should be upright. As a result, the y-axis acceleration of accelerometer 152 will have a value of approximately −1 g due to Earth gravity 154 (FIG. 6), where g is the Earth gravity acceleration. The above measurements apply regardless of the exact rotational position 160 of the compartment 102 around the upper calf 140. When the TENS device 100 is placed upside down at the top of the calf (which is a possible placement position), the accelerometer axis rotates as shown at 155 in FIG. In this case, a user standing upright and stationary will have an acceleration value of about +1 g measured along the y-axis. In contrast, a stationary recumbent user sleeping with his leg up on the bed will have an acceleration value of about 0 g measured along the y-axis. In a preferred embodiment, if the absolute value of the y-axis acceleration measurement is greater than the threshold, the leg ridge is considered upright, otherwise the leg ridge is considered recumbent.

  Turning now to FIG. 7, the Earth's gravity vector is downward, and the elevation angle θ (172) represents the angle between the accelerometer y-axis plus direction (174) and the true horizontal plane (170). In the preferred embodiment, the y-axis acceleration measurement threshold is set to 0.50 g from the horizontal plane corresponding to the leg ridge angle θ≈30 °, although other thresholds may be used and the user may In order to better discriminate between the behavior of and the wakefulness, you may have the option of adjusting this value.

In general, the acceleration measured along the y-axis should include not only the projection of gravity onto the y-axis, but also the contribution from motion, as
A _y (t) = ± sin | θ (t) | + m (t) [unit: g]
Here, t is time, and m (t) is contribution by leg movement. The specific ± sign depends on the placement of the TENS device in the upper calf 140 and is fixed for each placement. The motion component m (t) is considered “noise” in the situation of determining leg bulges, and the average over a sufficiently long time window should be zero.

  In a preferred embodiment, the leg lift algorithm that takes into account the user's body movements is implemented by the processor 515 of the user state (ie leg direction and leg movement) detector 500 in the following manner.

Step 1. The target angle threshold θ ₀ of angle θ (this is “threshold 1” shown in step 910 of FIG. 10) corresponds to the case where | θ | <θ ₀ and the user's upper calf 140 are lying down. Set to In the preferred embodiment, the target angle threshold θ ₀ is set to 30 °.

Step 2. Define a non-overlapping time window of length N, called “epoch”. The time at the end of each epoch is denoted T. In a preferred embodiment, accelerometer data (in standard earth gravity units g) is partitioned into epochs (ie, a 1 minute time window). In the situation of 10 Hz sampling rate for accelerometer data, the length of the epoch is N = 600. Based on samples of each epoch, the average value _{A y, T} and standard deviation _{SE Y} of the average _{value, T} is computed.

Step 3. Let θ _T = sin ⁻¹ A _{y, T.} A value of θ _T ≈θ ₀ can lead to unstable switching of the leg protuberance state. In order to reduce this, a hysteresis band θ ₀ ± θ _H is defined. In the preferred embodiment, the hysteresis parameter θ _H is set to 2.5 °, although other values are possible (but should be small compared to θ ₀ ). In the preferred embodiment, instead of calculating sin ⁻¹ for all epochs, instead the angle threshold is converted into units of acceleration, ie two thresholds Α _± = sin (θ ₀ ± θ _H ). By calculating, _{Ay, T} will be compared against them.

Step 4. The ability of the hysteresis band to prevent unstable switching of the leg uplift depends on the amount of noise in the data characterized by SEY _{, T,} which is the standard deviation of the mean value _{Ay, T.} To account for the noise level in the data, the processor 515 of the user state (ie leg direction and leg movement) detector 500 compares the acceleration data A _{y, T} to a threshold A _± . However, the processor 515 compares the “confidence interval” A _{y, T} ± ηSE _{Y, T} with the threshold A _± instead of comparing the average value _{Ay, T} itself with the threshold A _± . More specifically, for each epoch, if the previous raised state was recumbent, to classify the next state as upright, the processor 515 of the user state (ie leg direction and leg movement) detector 500 is , [| A _{y, T} | −ηSE _{Y, T} ]> A ₊ . If the previous uplift state was upright, to classify the next state as recumbent, the processor 515 of the user state (ie, leg direction and leg motion) detector 500 would [[A _{y, T} | + ηSE _{Y ,} T] <a _- requires that the. In the preferred embodiment, η = 3, but other values are possible.
Instantaneous Activity In one preferred form of the invention, the processor 515 of the user state (ie leg direction and leg movement) detector 500 is configured to detect instantaneous activity.

More particularly, when the TENS device 100 is worn on the user's upper calf 140, user activity will be captured by the TENS device accelerometer 152. Each axis (x, y, z) of the accelerometer 152 measures the projection of the acceleration vector along that axis. As explained above, the measured acceleration includes not only the contribution from leg movements but also the static effects of earth gravity. To separate contributions from leg movement, the processor 515 of the user state (ie leg direction and leg movement) detector 500, prior to further processing, the instantaneous data vector A (t) = [A _x (t) , A _y (t), A _z (t)].

  The acceleration component for each axis of the accelerometer contains useful information specific to analyzing body movements, but the magnitude of the acceleration vector called "instantaneous acceleration"

But,

And is commonly used to quantify the overall activity associated with exercise. In a preferred embodiment of the present invention, the processor 515 of the user state (ie leg direction and leg movement) detector 500 is responsible for this instantaneous acceleration.

Is used to calculate the sleep / wakefulness detection method. However, calculations based on other combinations of acceleration axes can also be used. For example, as defined above

Rather than combining all three axes uniformly as in, only a few axes may be used, or specific axes may be contrasted by subtraction.
Leg Motion Detector In one desirable form of the invention, the processor 515 of the user state (ie leg direction and leg motion) detector 500 may be configured to detect leg movement.

  More specifically, instantaneous acceleration

Is a time series consisting of short-term events, such as leg movements, known to occur during normal and abnormal sleep, and sustained activity that occurs during walking, running, climbing stairs, etc. is there. In a preferred embodiment, leg movement (LM) is in a manner consistent with periodic leg movement (PLM) detection as defined in the clinical literature (Bonnet et al., 1993 and Zucconi et al., 2006). Although calculated, other approaches for detecting short leg movements are possible and are considered to be within the scope of the present invention.

  In a preferred embodiment, the algorithm for detecting leg movement (LM) is implemented by the processor 515 of the user state (ie leg direction and leg movement) detector 500 in the following manner.

  Step 1. Two thresholds have been found by data analysis to be sensitive and unique to short leg movements (these are “threshold 2” shown in step 914 of FIG. 10 and steps 918). Defined as “threshold 3”). In a preferred embodiment suitable for the dispersion characteristics of the data measured by the accelerometer 152, these thresholds are 0.02g (816 in FIG. 8) and 0.03g (815 in FIG. 8), but others The value of can also be used.

Step 2. Define an instantaneous activity state (IAS) and initialize IAS to false.
Step 3. Instantaneous acceleration for each time

Calculate
Step 3. The IAS is updated for each time as follows. IAS = false,

If so, set IAS = true. IAS = true,

If so, set IAS = false. The two thresholds used in this way implement a hysteresis in a simple way that prevents rapid switching of the IAS.
Step 4. When the IAS becomes true, the leg movement (LM) period begins. The LM period ends when the IAS becomes false and remains false for more than 0.5 seconds. Thus, a continuous time interval of IAS = true, surrounded by a period of IAS = false, constitutes a leg movement (LM) period. However, if the separation of adjacent periods in which IAS is true is less than 0.5 seconds, this short period in which IAS was false is ignored.

  The top panel (810) in FIG. 8 shows an example of a leg motion (LM) detection algorithm applied to real data. Time is measured instantaneously, ie in steps of 0.1 seconds. Each point and the line 812 connecting these points are instantaneous accelerations.

It is. The vertical line 813 is

Was initially above the threshold 815 (threshold = 0.03 g), at which point IAS was set to true. Instantaneous acceleration

Dropped below the second threshold 816 (threshold = 0.02 g) before the 90th instant. However, the period that was less than the second threshold 816 was ignored because it was shorter than 0.5 seconds and the LM period continued. The instant indicated by the vertical line 814 is

Is below the second threshold 816 for the first time by 0.5 seconds or more, so the LM period ends. The end result is an LM period with 89 instantaneous periods (ie 8.9 seconds).
Body Rotation Detector In one preferred form of the invention, the processor 515 of the user state (ie leg direction and leg movement) detector 500 is configured to function as a body rotation detector.

  More particularly, when the TENS device 100 (FIG. 9) is worn on the lower part of the user's leg (ie, the upper calf 140) and the user is in a recumbent position, the accelerometer 152 is in its xz plane. It senses the projection of gravity. The angle φ between the x-axis of the device and the gravity vector −g can be calculated based on the projected gravity values in the x-axis and z-axis. The axis z 'coincides with the direction of the "thumb" of the user's leg to which the TENS device 100 is attached. When the TENS device is securely placed in the lower part of the user's leg (ie, the upper calf 140), the angle α between the device's z-axis and the leg's x'-axis is fixed.

  Finally, the body orientation angle β defines the relative rotational position between the leg (defined as the direction indicated by the big toe, ie, the z ′ axis) and the earth's gravity (z ″ axis). When measuring from the x ′ axis to the x ″ axis, the value of the angle remains the same. The relationship between β and φ is easy to derive as follows:

β = 180−α−φ
Since the angle α is fixed, the leg rotation angle β can be derived from the angle φ measured by the accelerometer 152.

  Some brief increase in activity, which is classified as leg movement (LM), is associated with a large change in the rotation angle φ measured by the TENS device 100. A sufficiently large rotation is unlikely to contain only legs, and should indicate that the whole body has turned over when sleeping, eg from left to right or from supine to left or right . Thus, some leg movements (LM) can be classified as “body rotation events”.

  In one preferred embodiment, the body rotation detection algorithm is implemented by the processor 515 of the user state (ie leg direction and leg movement) detector 500 using only the angular change Δφ in the following manner.

  Step 1. For each detected LM period, a raw acceleration vector A (t) with a short time window is selected before and after leg movement. In the present invention, this time window is instantaneous (0.1 seconds).

Step 2. Before and after each LM period, A (t) (not high-pass filtered) in each axis to obtain A _x (t), A _y (t), and A _z (t) Instantaneous values are obtained separately.

Step 3. Using these values before and after LM, the rotation angle φ (t) = atan2 {A _x (t), A _z (t)} is calculated. The arc tangent function atan2 returns an angle in the range of −180 ° <φ (t) <180 °, ie results in all four possible quadrants.

Step 4. Change in rotation angle Δφ = φ _after −φ _before is calculated. In order to facilitate comparison with a threshold (which is “threshold 4” shown in step 924 of FIG. 10), this difference is put in the range of −180 ° <Δ (φ) <180 °, That is, if Δφ> 180 °, 360 ° is reduced, and if Δφ <−180 °, 360 ° is added.

  Step 5. The absolute value | Δφ | is compared with a threshold value. In the present invention, this threshold is 50 °, but other values may be used. If | Δφ |> 50 °, the LM event is classified as a “body rotation event”.

The middle panel (820) of FIG. 8 shows this body rotation detection algorithm applied to real data. The acceleration values A _x (t), A _y (t), and A _z (t) are plotted in traces 821, 822, and 823. Throughout the event, the y-axis component A _y (t) ≈0 g is consistent with the condition that the lower leg ridge is in a recumbent state. In contrast, A _x (t) and A _z (t) show significant activity, especially between times 30 and 70. In addition, the steady-state value of A _x (t) varies from +1 g (before the LM period) to −1 g (after the LM period), suggesting a body rotation event.

  The lowermost panel (830) in FIG. 8 shows the calculation of the elevation angle θ (833) and the rotation angle φ (834) for each instant. Throughout the event, the elevation angle θ≈0 is consistent with the lower part of the leg being a recumbent protuberance. In contrast, the rotation angle φ has changed from φ≈ + 90 ° (represented by the white circle 831) to φ≈88 ° (indicated by the black circle 832). The change in angle is Δφ≈178 °, which coincides with the rotation of the whole body (in the right direction).

  These body rotations may be reported directly to the user to inform about the user's sleep pattern. In addition, body rotation events can be brief and no activity-related increase in the epoch average of activity can be apparent, and therefore the epoch may not be classified as arousal. Rolling over in bed may not represent an arousal state and represents a brief restless sleep. This novel technique for detecting body rotation by assessing the change in rotation angle associated with short leg movement (LM) is independent of body rotation from leg movement related to body rotation. It provides a finer explanation of sleep patterns that allow differentiating leg movements and therefore useful for clinical diagnosis.

  In another preferred embodiment, in order to improve robustness against noise, rather than using a single instantaneous A (t) before and after LM to calculate the angle φ, The average or median value of A (t) over that instant is used.

In another preferred embodiment, the body rotation detection algorithm is implemented by the processor 515 of the user state (ie, leg direction and leg movement) detector 500 using the angular change Δβ in the following manner. Consider a person sleeping with his TENS device on his right leg and lying on his back. When the toes are pointing vertically upwards, β = 0 if the TENS device is placed on either leg, and β increases with counterclockwise (CCW) rotation, thus turning the leg Recall that the range of positions is most likely −80 ° ≦ β ≦ 0 °. Any change Δβ in the angle that stays within that range will probably not be related to body rotation. In contrast, a change in angle Δβ from within the range to outside the range is most likely related to body rotation. Thus, the threshold for detecting body rotation can be adjusted using the change in angle Δβ depending on the leg on which the device is placed. That is, in addition to the magnitude of the change Δβ, the value of the leg rotation angle β before and after the leg movement (LM) and the sign of the angle change Δβ over the leg movement (LM) Can be used to improve performance.
Static Body Rotation Position Detector In one desirable form of the invention, the processor 515 of the user state (ie, leg direction and leg motion) detector 500 is intended to function as a static body rotation position detector. Can be configured.

More specifically, users with sleep apnea are encouraged not to sleep on their back.
Since the rotation range of the human hip movement is limited, the rotation position of the legs has a high correlation with the body position, for example, when sleeping on his back, the toes of either foot have various degrees of horizontal plane It is unlikely that it will be directed in the direction of the horizontal plane and precisely in the direction of the horizontal plane, and may not be directed downward of the horizontal plane. This observation, along with the placement of a novel TENS device at the top of the user's calf, enables an innovative reinforcement to sleep analysis.

  "Epoch" time scale equal to 1 minute, and epoch averaged, high pass filtered

,

,and

Is introduced above in the paragraph titled “Detection of Leg Protrusion”. Since the time spent sleeping on the back is sufficient to report with a resolution of 1 minute, these epoch averaged acceleration values are advantageously used in the following ways to detect static body rotation positions: Can be done.

  Consistent with the definition of the rotation position angle φ of the rotation detector, as before

And here

and

Is the acceleration averaged over the epoch T, raw (ie not high-pass filtered). Let β _T = toe angle relative to vertical. relationship between phi _T and beta _T relies on rotating arrangement represented by the TENS device in calf top of user alpha. Since the electrode gel 444 is sticky and the strap 110 is a support, the TENS device does not move on the user's leg once placed on the calf top 140, so the TENS device is on the user's leg. As long as the angle is constant.

  Referring now to FIG. 9, the double prime coordinate system (ie, x ″, y ″, z ″, which is not seen in FIG. 9 since y ″ extends below the leg axis) 9 is fixed to the earth along the vertical axis and is a single prime coordinate system (ie, x ′, y ′, z ′, and y ′ extends below the leg axis, so FIG. (Not seen) is fixed relative to the leg and has a primeless coordinate system (ie, x, y, z, and y is not seen in FIG. 9 because it extends below the leg axis) Is

and

Is fixed with respect to the TENS device. The earth coordinate system has a z "axis along the vertical, the leg coordinate system has a z 'axis in the toe direction, and the leg rotation angle β is between the x" axis of the earth and the x' axis of the leg. Is an angle. The angle α of the TENS device is the position of the TENS device on the leg, measured from the x ′ axis of the leg. Using the accelerometer axis information in a TENS device and the standard geometry techniques, including identification of similar triangles, it can be shown that these angles are simply related by β = 180−α−φ. It will be obvious to the contractor. Thus, at each epoch, these angles are simply related by β _T = 180−α−φ _T.

  In the preferred embodiment, the following simple procedure is used by the processor 515 of the user state (ie leg orientation and leg movement) detector 500 to determine whether the user is supine by estimating the angle β. The

  Step 1. The user places the TENS device on his / her lower limb and secures the strap 110 around the upper calf 140, lies with the legs approximately horizontal and lies down, and the toes are standing still vertically upwards.

  Step 2. The user informs the TENS device that the above conditions have been met. This indication takes the form of a series of button presses (eg, using button 106), a series of taps on the compartment 102, as detected by the accelerometer 152, or instructions on the smartphone 860 communicating with the TENS device 100. It's okay.

  Step 3. Β≈0 with the toes straight up, so

It is obvious that we estimate

Is estimated from accelerometer data acquired during the period when the toes are facing up. For ease of calculation, this difference is

In the range of

If so, reduce 360 °

If so, add 360 °.
Step 4. This value for all epochs ending at time T

The

Used to calculate In order to facilitate comparison with the threshold, this difference is put in the range of −180 ° <β _T ≦ 180 °, that is, if β _T > 180 °, 360 ° is reduced, and β _T ≦ −180 °. Add 360 °.

Step 5. Define a range of values of beta _T corresponding to the user that, or sleeping lying on his back. In the preferred embodiment, all epochs with −80 ° <β _T <80 ° are classified as “back-up”. Since this range is symmetric, the algorithm is valid no matter which TENS device is placed on either leg. Avoiding ± 90 ° by 10 ° excludes values that may occur when the user is sleeping sideways or sleeping. In another preferred embodiment, the threshold (which should be present in step 930 of FIG. 10) depends on the leg on which the device is placed. For example, if the device is placed on the left leg, the range of angles while lying on its back is usually 0 ° <β _T <80 °. Alternatively, if the device is placed on the right leg, the range of angles while lying on its back is usually −80 ° <β _T <0 °.

  Step 6. When a user with sleep apnea selects this option for the TENS device 100, when the user is determined to be asleep, i.e. lying on low activity, several sets of times, for example several minutes The TENS device notifies the user that he is lying on his back beyond. This indication can be, for example, a form of vibration of the TENS device itself, or an alarm on the smartphone 860.

Step 7. After determining the time (minutes) that the user is likely to sleep, that is, lying down with a low degree of activity, the time (minutes) at which the user is determined to be lying on the back is determined. This ratio is reported to this user using, for example, the smartphone 860.
Exemplary Operation In one desirable form of the invention, a TENS device 100 that includes a user state (ie, leg direction and leg movement) detector 500, its processor 515, and its controller 520 is shown in the flowchart of FIG. Programmed to work in the manner shown.

  More specifically, when the TENS device 100 securely attached to the user's upper calf 140 is turned on, the user state (ie, leg direction and leg motion) detector 500 is accelerated as shown in step 902. Data is collected from total 152, real-time clock 505 and ambient light detector 510. In addition, the skin surface detector 521 verifies that the electrode array 120 of the TENS device 100 is in contact with the user's skin as shown in step 904 (thus, the TENS device 100 is placed on the user's upper calf 140). Make sure it is securely attached).

As shown in step 906, the processor 515 analyzes the data from the accelerometer 152, the real time clock 505, and the ambient light detector 510.
The processor 515 determines whether the user is sleeping by determining the user's leg ridge direction, as shown in step 908, and comparing the elevation angle with a threshold (ie, “threshold 4”), as shown in step 910. Determine if.

If the processor 515 determines that the user is sleeping, the processor 515 determines the user's leg activity, as shown in step 912.
As shown in step 914, if the user's leg activity is compared to a threshold (ie, “threshold 1”) and the user's leg activity is less than threshold 1, the processor 515 returns the user as shown in step 916. Determines that she is sleeping peacefully.

  The processor 515 compares the user's leg activity (determined in step 912) with another threshold (ie, “threshold 2”), as shown in step 918, and if the user's leg activity exceeds the threshold 2, The processor 515 determines that the user is moving the leg excessively, as shown in step 920.

  In addition to the foregoing, the processor 515 also determines the direction of the user's leg rotation, as shown in step 922, and determines the change in the angle of the user's leg rotation, as shown in step 924, with another threshold (ie, “ If the change in the angle of the user's leg rotation exceeds the threshold 3 and the movement of the user's leg exceeds the threshold (ie, “threshold 2”) as shown in step 918, compared to threshold 3 ”) The processor 515 determines that a body rotation event has occurred, as shown in step 926.

  The processor 515 also determines the user's leg rotation direction determined in step 922, the accelerometer data analysis determined in step 906, and the user's limb and toe direction determined in step 928. , And the classification of the user's body position is determined as shown in step 930.

The processor 515 then characterizes the user's position, such as “upright”, “(left / right) sideways” or “prone” as shown in step 932.
The information derived at steps 916, 920, 926 and 932 is then utilized by the processor 515 to analyze the user's sleep period, as shown at step 934. The results of this sleep analysis (determined in step 934) may then be displayed (as shown in step 936) and provide feedback to the user or the user's caregiver (as shown in step 938). And / or may be used to instruct the controller 520 to adjust the stimulation current supplied by the TENS device 100 (as shown in step 940).
It will be appreciated that the present invention provides a transcutaneous electrical nerve stimulator with automatic monitoring of leg activity and leg orientation. The leg direction includes a state of leg bulge and leg rotation and a change in state of leg bulge and leg rotation. The TENS stimulator may be pre-programmed to change its behavior in response to sensed user leg activity and leg position during bedtime. In addition, leg orientation and leg activity are used to assess sleep quality and sleep posture, all of which are important aspects for improving sleep and health. Leg activity patterns can also be used to diagnose sleep disorders such as periodic leg movements, and TENS stimulators can be used to relieve excessive leg movements that cause disruption to sleep.

  The present invention can be realized without a neural stimulation function. Body movement and position can be monitored and quantified without the need for neural stimulation using the present invention. The monitoring device (device) can be placed in other positions, such as the upper part of either limb.

  Moreover, many additional modifications in the details, materials, steps, and arrangements of parts described and illustrated herein by those skilled in the art to illustrate the nature of the present invention will fall within the principles and scope of the present invention. It should be understood that this can still be done.

Claims (54)

An apparatus for providing a user with transcutaneous electrical nerve stimulation (TENS) therapy comprising:
A housing;
A mounting unit for providing a mechanical coupling between the housing and the user's body;
A stimulation unit for electrically stimulating at least one nerve of the user;
A sensing unit for sensing the user's body movement and body direction;
A reporting unit for providing feedback to the user based on the sensed body movement and body orientation of the user.   The apparatus according to claim 1, wherein the mounting unit is a flexible band.   The apparatus of claim 1, wherein the mounting unit communicates a state of mechanical coupling between the housing and the user's body to the sensing unit.   The apparatus of claim 3, wherein the state of the mechanical coupling between the housing and the user's body is determined by a mechanical element.   The apparatus of claim 4, wherein the mechanical element is a tensiometer.   The apparatus of claim 4, wherein the state of the mechanical coupling between the housing and the user's body is determined by an electrical element.   The apparatus of claim 6, wherein the electrical element measures a voltage value of a voltage divider circuit formed by the housing and the user's body.   The apparatus of claim 1, wherein the sensing unit uses data from an electromechanical sensor.   The apparatus of claim 8, wherein the state of the mechanical coupling between the housing and the user's body determines the usefulness of the data from the electromechanical sensor.   The apparatus of claim 8, wherein the electromechanical sensor is an accelerometer.   The apparatus of claim 1, wherein the sensing unit determines an orientation state of the user's body using an analysis unit that operates in a gravitational acceleration measurement of the earth.   The apparatus of claim 11, wherein the user's body orientation includes one of a set consisting of upright or lying.   13. The apparatus of claim 12, wherein the analysis unit is a programmable microprocessor that averages a projection of the gravitational acceleration measurement on an axis of a sensor of the electrical machine and compares the average value to a threshold value.   The apparatus of claim 13, wherein the axis coincides with a longitudinal direction of the user's body.   14. The apparatus of claim 13, wherein the threshold is one half of a standard Earth gravity acceleration value.   The apparatus of claim 13, wherein the average value is calculated over a period of 1 minute.   The apparatus according to claim 13, wherein if the average value is less than the threshold value, the state of the user's body direction is determined to be lying.   9. The apparatus of claim 8, wherein the sensing unit determines the state of movement of the user using an analysis unit that operates on the data from the electromechanical sensor.   The apparatus of claim 18, wherein the motion state is considered active if the processed characteristic of the data is within a target area.   The apparatus of claim 19, wherein the processed characteristic is an average value of a combination of filtered components of the data from the electromechanical sensor.   21. The apparatus of claim 20, wherein the combination is a square root of the sum of squares of the filtered components.   21. The apparatus of claim 20, wherein the filtering is removing static earth gravity components from the data from the electromechanical sensor.   21. The apparatus of claim 20, wherein the component is individual axis data from the electromechanical sensor.   The apparatus of claim 19, wherein the target area includes all values above a threshold.   The apparatus of claim 19, wherein the target region has a boundary incorporating a hysteresis band.   The apparatus of claim 25, wherein the width of the hysteresis band depends on an estimated noise level of the data from the electromechanical sensor.   The apparatus of claim 1, wherein the body direction is a rotational direction in a plane perpendicular to a longitudinal axis of the user's body.   28. The apparatus of claim 27, wherein the sensing unit uses data from an electromechanical sensor and the direction of rotation is estimated by analyzing the output of the electromechanical sensor.   29. The apparatus of claim 28, wherein the output of the electromechanical sensor is an average of the projection of earth gravity onto a plane perpendicular to the longitudinal axis of the user's body.   30. The apparatus of claim 29, wherein the analysis includes estimating an angle formed by the average of the projection of earth gravity.   31. The apparatus of claim 30, wherein a calibrated body rotation direction is the estimated angle obtained with reference to a rotation direction angle in a known body direction.   32. The apparatus of claim 31, wherein the known body orientation is such that the user lies on his back with his toe up. The sensing unit uses data from an electromechanical sensor, and the state of the mechanical coupling between the housing and the user's body determines the usefulness of the data from the electromechanical sensor; The electromechanical sensor is an accelerometer, and the sensing unit determines an orientation state of the user's body using an analysis unit that operates in a gravitational acceleration measurement of the earth, and the orientation state of the user is Including one from a set consisting of upright or lying down,
The sensing unit determines a state of movement of the user using an analysis unit that operates on the data from the electromechanical sensor, and if the processed characteristic of the data is within a target area, the movement Is considered active,
The apparatus of claim 1, wherein the reporting unit calculates an accumulated time during which the user's body orientation is lying.   34. The apparatus of claim 33, wherein the reporting unit calculates the accumulated time when the user's movement status is not active and the user's body orientation is lying down.   34. The apparatus of claim 33, wherein the reporting unit calculates a difference distribution of angular differences in the direction of rotation of the user's body.   36. The apparatus of claim 35, wherein each pair of angles is measured immediately before and immediately after the user's movement state is active when the user's body orientation is lying down.   36. The apparatus of claim 35, wherein the reporting unit calculates a duration when the user's calibrated body rotation angle is within a target range.   38. The apparatus of claim 37, wherein the target range is independent of limb indication.   38. The apparatus of claim 37, wherein the target range depends on an indication of the limb.   38. The apparatus of claim 37, wherein the feedback is activated when a calibrated body rotation direction of the user is within the target range.   36. The apparatus of claim 35, wherein the feedback is activated when the distribution meets a set of criteria.   42. The apparatus of claim 41, wherein the set of criteria is the percentage difference having a value that exceeds a threshold greater than a predetermined percentage.   38. The apparatus of claim 37, wherein the feedback is activated when the duration exceeds a threshold.   The apparatus of claim 1, wherein the feedback is providing mechanical vibration to the user.   The apparatus of claim 1, wherein the feedback is providing an electrical stimulus to the user.   The apparatus of claim 1, wherein the feedback includes adjustment of the stimulation unit.   47. The apparatus of claim 46, wherein the adjustment results in a change in TENS stimulus intensity.   47. The apparatus of claim 46, wherein the adjustment results in a change in TENS stimulation frequency.   47. The apparatus of claim 46, wherein the adjustment results in a change in TENS stimulation start time.   The apparatus of claim 1, wherein the feedback is an alert sent to the user by at least one selected from a set consisting of a smartphone and another connected device. A method for providing percutaneous electrical nerve stimulation to a user, comprising:
Attaching a stimulation unit and a sensing unit to the user's body;
Applying electrical stimulation to the user using the stimulation unit to stimulate one or more nerves;
Analyzing electrical machine sensing data from the sensing unit to quantify the user's body orientation and body activity level;
Changing the electrical stimulation applied by the stimulation unit based on the user's body orientation and body activity level. An apparatus for monitoring a user's sleep pattern,
A housing;
A mounting unit for providing a mechanical coupling between the housing and the user's body;
A sensing unit disposed within the housing to sense movement and body direction of the user;
A reporting unit for providing feedback to the user based on the sensed body movement and body orientation of the user. A method for monitoring a user's sleep pattern,
Attaching a sensing unit and a feedback unit to the user's body;
Using the sensing unit to determine body movement and body direction of the user;
Providing feedback to the user via the feedback unit based on physical activity and body orientation. An apparatus for providing a user with transcutaneous electrical nerve stimulation (TENS) therapy comprising:
A housing;
A mounting unit for providing a mechanical connection between the housing and a user's leg;
A stimulation unit for electrically stimulating at least one nerve of the user;
A sensing unit for sensing the user's leg direction and leg movement, wherein sensing the user's leg direction includes determining the user's leg protuberance and leg rotation, comprising: A sensing unit comprising sensing the user's net activity and leg movement; and
A controller for adjusting the stimulation unit based on a determination by the sensing unit.

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