JP6769967B2 - Extended transcutaneous electrical nerve stimulator with automatic detection of leg orientation and movement for extended sleep analysis - Google Patents

Description

Reference to earlier pending patent application This application is
(1) Previous US Patent Application No. 14 / 794,588 pending filed on July 8, 2015 by NeuroMetalix and Xuan Kong et al., "MEASURING THE" ON-SKIN "TIME OF A TRANSCUTANEOUS ELECTRICAL NER. SIMULATOR (TENS) DEVICE IN ORDER TO MIMINIZE SKIN IRRITATION DUE TO EXCESSIVE UNINTERRUPTED WEARING OF THE SAMEM "(representative number NEURO-73)
(A) NeuroMetalix and Shai N. et al. Previous US Patent Application No. 14 / 610,757 pending filed by Gozani et al. On January 30, 2015, "APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION". This is a partial continuation application of CON), and this application is
(I) NeuroMetalix and Shai N. et al. Previous US Patent Application No. 13 / 678,221 filed by Gozani et al. On November 15, 2012, "APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION" (representative number 59) It is an application, and this application is
(A) Shai N. Previous US Patent Provisional Application No. 61 / 560,029, "SENSUS OPERATING MODEL" (agent reference number NEURO-59 PROV), filed by Gozani on November 15, 2011, and (b) Shai N. et al. US Patent Provisional Application No. 61 / 657,382, filed by Gozani et al. On June 8, 2012, "APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION" (Representative) (1) is to insist on the interests of
(B) Previous US Patent Application No. 14 / 269,887, pending on May 5, 2014, filed by NeuroMetalix and Thomas Ferree et al., "TRANSCUTANEOUS ELECTRICAL NERVE STIMULATOR WITH USTER TESTURE". This application is a partial continuation application of "DETECTOR, WITH TRANSIENT MOTION DETECTOR FOR INCREASING THE ACCURACY OF THE SAME" (agent reference number NEURO-6667).
(I) Previous US Patent Application No. 14 / 230,648 pending filed on March 31, 2014 by NeuroMetalix and Shai Gozani et al., "DETECTING CUTANEOUS ELECTRODE PEELING USING ELECTRODE-SKIN IMPEN". This application is a partial continuation application of reference number NEURO-64).
(A) US Patent Provisional Application No. 61 / 806,481, filed by Shai Gozani on March 29, 2013, "DETECTING ELECTRODE PEELING BY RELATIVE CHANGES IN SKIN-ELECTRODE IMPEDANCE" (agent reference number NEC). 64 PROV) is claimed, and (B) is
(Ii) Previous US Patent Application No. 14 / 253,628 pending filed on April 15, 2014 by NeuroMetalix and Shai Gozani et al., "TRANSCUTANEOUS ELECTRICAL NERVE STIMULATOR WITH AUTOMATIC EDIT. (Agent reference number NEURO-65) is a partial continuation application, and this application is
(A) US Patent Provisional Application No. 61 / 811,864, filed by Shai Gozani on April 15, 2013, "TRANSCUTANEOUS ELECTRICAL NERVE STIMULATOR WITH AUTOMATIC DETESTION OF PATION OF PATIENT SLEEP- It claims the interests of NEURO-65 PROV), and (B) is
(Iii) U.S. Patent Provisional Application No. 61 / 819,159, filed on May 3, 2013 by Neurometrix and Thomas Ferree et al., "TAP DETECTOR WITH HIGH SENSITIVITY AND SPECIFICITY FORACERUARTAWEAR" (Agent reference number NEURO-66 PROV) claims the benefit, and (B) is
(Iv) U.S. Patent Provisional Application No. 61 / 858,150, filed on July 25, 2013 by Neurometrix and Andres Aquarre et al., "MOVEMENT REGULATED TRIP CONDITIONS IN A WEAR TRANSELATIONS IN A WEAR TRANSTURE It claims the benefit of reference number NEURO-67 PROV), and (1) is
(C) US Patent Provisional Application No. 62 / 021,807, "MEASURING TENS DEVICE ON-SKIN TIME TO PREVENT AND MINIMIZE SKIN", filed on July 8, 2014 by Neurometrix and Xuan Kong et al. It claims the interests of the agent reference number NEURO-73 PROV), and this application is
(2) U.S. Patent Provisional Application No. 62 / 213,978, "TRANSCUTANEOUS ELECTRICAL NERVE STIMULATOR WITH OUTOMATIC EDITION "ANALYSIS" (agent reference number NEURO-77 PROV), and (3) US Patent Provisional Application Nos. 62 / 101,029, "METHOD" filed on January 8, 2015 by Neurometrix and Shai Gozani et al. AND APPARATUS FOR USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION TO AID SLEEP ”(agent reference number NEURO-69A PROV) is claimed.

The 15 patent applications mentioned above are incorporated herein by reference.
The present invention generally relates to a transcutaneous electrical nerve stimulation (TENS) device that applies an electric current over the user's intact skin through electrodes 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 is an extended process using the above devices and methods. Includes Transcutaneous Electrical Nerve Stimulation (TENS).

Chronic pain due to diabetic neuropathy and other causes can interfere with sleep, which is associated with a number of complications. Transcutaneous Electrical Nerve Stimulation (TENS) devices reduce pain by stimulating sensory nerves, which results in an increase in endogenous opioids and a downward regulation of the transmission of pain signals to the brain. TENS devices that can be used during sleep should provide a unique opportunity to relieve pain during sleep with the goal of improving sleep (eg, Barbarisi M, Pace MC, Passavanti MB et al., Pregabalin. And transcutaneous electrical neural stimulation for transcutaneous neuralgia treatment ”, Clin J Pain, September 2010, 26 (7): 567-572).

However, most TENS devices are designed to operate exclusively during the day (ie, during wakefulness) rather than at night (ie, during sleep). This limitation is evident in the design of conventional TENS devices, where current is applied through wires (called leads) connected to electrode pads on the skin. Such a design could cause the leads to get in the way, get tangled or pulled, and the electrode pads could come off the skin (which would end the TENS treatment), or perhaps worse, from the skin. It is impractical for use during sleep as it may partially peel off and increase current density, which can have negative consequences for the user (eg discomfort or, in extreme cases, burns). Or it's not safe.

Previous US Patent Application No. 14 / 230,648 pending filed on March 31, 2014 by NeuroMetalix and Shai Gozani et al., "DETECTING CUTANEOUS ELECTRODE PEELING USING ELECTRODE-SKIN IMPEDANCE". -64) was published as US Patent Application Publication No. 2014/0296934 A1 on October 2, 2014, and is incorporated herein by reference here, not only during the daytime (ie, during awakening). , A novel TENS device is disclosed that allows TENS treatment to be applied even at night (ie, sleeping state). Key design elements that make this novel TENS device suitable for use during sleep are: (1) the electrodes are attached directly to the housing containing the TENS stimulation circuit and thus the leads are removed, (2) TENS. The housing and electrode pads are securely and comfortably held against the skin by adjustable straps or bands. (3) The TENS device has the electrode pads detached (completely or partially) from the skin. The skin-electrode contact impedance (and associated electrical parameters) is continuously measured to detect whether or not, and when peeling is detected, the current transmission is stopped, (4) The therapeutic stimulus is nighttime. It may be scheduled with an hour on / off block to relieve pain through, (5) the TENS device detects that the user is asleep and automatically adjusts the stimulation level of treatment so as not to interfere with sleep. It may be reduced to.

The novel TENS device disclosed in the earlier pending US Patent Application No. 14 / 230,648 (published as US Patent Application Publication No. 2014/0296934 A1) is located above the user's calf. It is designed to be. There are three reasons for this. First, the TENS device needs to stimulate sensory nerve fibers to relieve pain extensively due to the systemic effects of increased endogenous opioids and downward regulation of pain signal transmission. The upper calf region contains a mass of sensory nerve fibers that is close to the surface of the skin and can be easily activated using a transcutaneous electrical nerve stimulator. Second, 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 aforementioned (systemic) pain-suppressing mechanism by endogenous opioids. There is also evidence to substantiate a further mechanism of pain control, so it is advantageous to place the TENS device above the user's calf. Third, chronic pain can be relentless all day long and often worsens at night, but wearing a TENS device on the upper calf is milder, which facilitates more regular use.

As mentioned above, the novel TENS device disclosed in the previous pending US Patent Application No. 14 / 230,648 (published as US Patent Application Publication No. 2014/0296934 A1) is during sleep. Designed for use, when it detects that the user is asleep, it adjusts the stimulation level of the treatment so that it does not interfere with sleep. Quantifying sleep quality and sleep disorders also increases the likelihood of using TENS devices and improves sleep quality if users are aware of and convinced of the benefits of TENS devices over their sleep. Would be advantageous for TENS devices intended for.

A typical criterion for determining a subject's sleep-wake state is a polysomnography containing at least three distinct types of data, such as an electroencephalogram (EEG), an electroocular diagram (EOG), and an electromyogram (EMG). Due to the difficulty of recording and analyzing these types of data, sleep-wake determination methods have been developed and improved over the last three decades as a practical alternative for investigating sleep / wake patterns. ing. The sleep / wake determination method is generally a continuous recording of body movements by a device equipped with an accelerometer worn on the body [Ancoli-Israel S, Core R, Alessi C, Chambers M, Moorcroft W. , Pollak CP. The role of actigraphy in the circadian of sleep and circadian rhythms. Sleep. May 1, 2003, 26 (3), 342-392].

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

The placement of a TENS device equipped with an accelerometer on the upper calf with a mechanical coupling to the firm upper calf is a novel technique for detecting when the user is sleeping and for analyzing the user's sleep. Innovative metrics and innovative techniques for quantifying body and leg movements associated with poor sleep quality and / or disorders such as restless legs syndrome, and enhanced transcutaneous electricity utilizing them. It is now well recognized that it can be used to accommodate innovative techniques for providing neurostimulation (TENS). Some of these novel metrics can result in "leg movements", "body rotation events" associated with bed rollover, and chronic pain in the user, as well as snoring or sleep apnea. There is also "time on the back" that is associated with problematic sleep postures. In addition to tracking and reporting sleep indicators, real-time feedback to users based on indicator trends can also help users improve their sleep quality. One example is to alert the user (eg, by mechanical or electrical means) when the time to lie on his back exceeds a threshold. In another example, when a pattern of leg movement associated with discomfort caused by nocturnal pain is detected, the TENS stimulation parameters may be modified to extend the analgesic effect of TENS treatment.

Accordingly, the present invention comprises a novel TENS stimulator designed to be located above the user's calf and a preconfigured electrode array designed to stimulate the perimeter of the user's upper calf. It includes the provision and use of TENS devices. A three-axis (x, y, z) accelerometer built into the TENS device relies on the direction of the device to project static gravity onto each axis (ie, x, y, z) and the user on each axis. The acceleration that changes over time due to the movement along that axis is continuously measured.

The placement of a novel TENS device above the user's calf corresponds to a novel technique for detecting when the user is asleep, to quantify sleep and assess abnormal physical and leg movements, and , Used to provide extended TENS treatment using such sleep analysis.

First, the novel TENS device measures leg orientation, which is highly correlated with body orientation and thus indicates the user's lying state (thus indicating the user's sleep-wake state). It is a thing. Specifically, the novel TENS device is the "elevation" of the leg (ie the angle of the lower leg with respect to the horizontal) and the "rotation" of the leg (ie the angle of rotation of the lower leg around its own axis). Two distinct aspects of the leg direction are measured, such as.

Second, a novel TENS device measures leg movement, which also indicates the user's sleep-wake state. Specifically, the novel TENS devices are "net activity" (the magnitude of motion-related acceleration, averaged within a one-minute time window), and "leg movement" (ie, leg movement). Two distinct aspects of leg movement are measured, such as short-term events known to occur during sleep, but not apparent in net activity). Some leg movements with large leg rotations can be further classified as "body rotation events" (such as those that occur when turning over in bed). People with chronic pain and other medical conditions may experience repetitive leg movements, which can degrade the quality of sleep felt by the person (and his or her sleep partner). Quantification and monitoring of repetitive leg movements can provide insight into these conditions and trends in these conditions.

Third, the novel TENS device extends these two measurements of leg movement (ie net activity and leg movement) and two measurements in the leg direction (ie leg ridge and leg rotation) to extend the therapeutic benefits. ) To improve sleep quantification and utilize more accurate quantification metrics.

Determining sleep-wake status with a novel TENS device proceeds in several steps. The user is "sleeping" if the user's leg orientation is determined to be lying down (ie, close to horizontal) over a selected portion (eg, most) of the selected time period (eg, the time window to determine). Is considered. While sleeping, "sleep onset" is defined as the first time a user's net activity and leg movements fall below a set threshold over a defined period of time (eg, a time window to determine). .. Following the onset of sleep, a novel TENS device measures net activity and leg movements. Throughout all time intervals where net activity is below some defined threshold, the user is considered "sleeping". Throughout all of the time the user is lying down, net activity is below the threshold of some net activity, the number of leg movements is below the threshold of some leg movements, and the number of body rotations. Is zero and the user is considered "peaceful". The user is considered to be sleeping "on his back" throughout the time when the static rotation angle of the leg is between the two thresholds of the static rotation angle of the leg. 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 user's caregiver) and / or used to provide the patient with extended TENS treatment.

In one of the preferred embodiments of the present invention, a device for providing transcutaneous electrical nerve stimulation (TENS) therapy to a user is provided, the device.
With the housing
A mounting unit for providing a mechanical connection between the housing and the user's body,
A stimulus unit for electrically stimulating at least one nerve of the user,
A sensing unit for sensing the user's body movements and body orientation,
It includes a reporting unit for providing feedback to the user based on the perceived body movement and body orientation of the user.

In another desirable embodiment of the present invention, a method for applying transcutaneous electrical nerve stimulation to a user is provided, and the method is described.
Steps to attach the stimulation unit and sensing unit to the user's body,
With the step of applying electrical stimulation to the user using a stimulation unit to stimulate one or more nerves,
Steps to analyze electromechanical sensing data from the sensing unit to quantify the user's body orientation and body activity level,
It involves changing the electrical stimulus applied by the stimulus unit based on the user's body orientation and body activity level.

In another preferred embodiment of the invention, a device for monitoring a user's sleep pattern is provided, wherein the device.
With the housing
A mounting unit for providing a mechanical connection between the housing and the user's body,
A sensing unit located inside the housing to sense the user's body movements and body orientation.
It includes a reporting unit for providing feedback to the user based on the user's perceived body movements and body orientation.

In another preferred embodiment of the invention, a method for monitoring a user's sleep pattern is provided, wherein the method is described.
Steps to attach the sensing unit and feedback unit to the user's body,
Steps to determine the user's body movements and body orientation using the sensing unit,
Includes a step of providing feedback to the user via the feedback unit based on body activity and body orientation.

In another preferred embodiment of the invention, a device for providing transcutaneous electrical nerve stimulation (TENS) therapy to a user is provided, said device.
With the housing
With a mounting unit to provide a mechanical connection between the housing and the user's legs,
A stimulus 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 the step of sensing the user's leg direction includes a step of determining the user's leg ridge and leg rotation, and a step of sensing the user's leg movement. With a sensing unit that includes steps to determine the user's net activity and leg movements,
A controller for adjusting the stimulation unit based on the determination by the sensing unit is provided.

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

It is a schematic diagram which shows the novel TENS device formed by this invention attached to the upper part of a user's calf. It is the schematic which shows the novel TENS device of FIG. 1 in more detail. FIG. 2 is a schematic representation of the novel TENS device of FIGS. 1 and 2 attached to the patient's tissue. FIG. 5 is a schematic representation of the novel TENS device of FIGS. 1 and 2, including a detector of the user's condition (ie, leg direction and leg movement). The skin surface detection system of the novel TENS device 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. It is a schematic diagram which shows the direction of the accelerometer incorporated in the novel TENS device of FIG. 1 and FIG. 2 when the novel TENS device of FIG. 1 is attached to the upper part of a user's calf. An outline 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 upper part of the user's calf) is stationary at an elevation angle θ with respect to the horizontal plane. It is a figure. It is a schematic diagram which shows the detection of the leg movement (LM) event, and the calculation of the change Δφ (with respect to the event before) of the rotation angle φ of a device after an LM event. Mathematical processing to relate the accelerometer rotation angle φ (measured by the accelerometer) to the leg rotation angle β via a third angle α that represents the rotational position of the novel TENS device at the top of the user's calf. It is a schematic diagram which shows. FIG. 6 is a schematic flow diagram illustrating exemplary behavior of a novel TENS device, including a detector of the user's condition (ie, leg orientation and leg movement).

Overview of the Innovative TENS Device FIG. 1 shows how the innovative TENS device 100 formed by the present invention is worn on the upper part 140 of the user's calf. The user may wear the TENS device 100 on either leg.

The TENS device 100 shown in more detail in FIG. 2 preferably preferably refers to the stimulator 105, the strap 110, and the electrode array 120 (as is well known in the art, the cathode electrode and the stimulator 105). It has three main components (with connected anode electrodes). The stimulator 105 preferably comprises three compartments 101, 102 and 103 that are 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 a preferred embodiment of the invention, compartment 102 houses a TENS stimulation circuit (excluding batteries) and user interface elements 106 and 108. The compartment 102 is an accelerometer 152, preferably in the form of a semiconductor chip accelerometer, for detecting the user's gestures, the user's leg and body orientation, and the user's leg and body movements, as discussed below. Also accommodate (see FIGS. 4 and 6). The compartment 102 also accommodates the 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, and an ambient light sensor or detector 510 (FIGS. 4 and 6) for determining the state of ambient light. A type of wireless interface unit known in the art that allows the TENS device 100 to wirelessly communicate with other elements (eg, a portable electronic device such as a smartphone 860) with other auxiliary elements. A smaller auxiliary compartment that houses (not shown). 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 invention, many compartments are used, for example, to better adapt to the body and to 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 legs, thereby reducing volume.

Now, continuing to look at FIG. 2, the user interface element 106 preferably comprises a push button for the user to control the electrical stimulus, and the user interface element 108 for indicating the stimulus state and to the user. An LED is preferably provided to provide other information. Additional user interface elements (eg, arrays of multiple LEDs, LCD displays, audio feedback via pagers or audio outputs, tactile devices such as vibration motors) may also be provided and are considered within the scope of the invention.

A preferred embodiment of the present invention is designed to be worn on the user's upper calf 140, as shown in FIG. A TENS device 100 with 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.

A preferred embodiment of the invention places the TENS device above the user's calf, but additional anatomical positions (such as above the lumbar region, above the knee, and above the upper arm) are also contemplated and are within the scope of the invention. Be considered.

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

Further details regarding the construction and use of the aforementioned aspects of the TENS device 100 are available (i) on February 3, 2015, by NeuroMetalix and Shai N. et al. U.S. Pat. Nos. 8,948,876 issued to Gozani et al., "APPARATUS AND METHOD FOR RELIEVING PAIN USING TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION" (agent reference number NEURO-5960), Previous US Patent Application No. 14 / 230,648 filed by Gozani et al. On March 31, 2014, "DETECTING CUTANEOUS" ELECTRODE PEELING "USING ELECTRODE-SKIN IMPEDANCE" (agent reference number NEURO-64). ), (Published as US Patent Application Publication No. 2014/0296934 A1 on October 2, 2014), the above US patents and US patent applications are hereby incorporated by reference. Be incorporated.
User Condition (ie, Leg Direction and Leg Motion) Detector According to the present invention, the user condition (ie, leg direction and leg motion) detector 500 further provided by the TENS device 100 (eg, inside compartment 102) is (i). To determine a user's sleep-wake state, (ii) to analyze the user's sleep, and / or (iii) use the TENS device 100 to deliver enhanced transcutaneous electrical nerve stimulation (TENS). It is for doing. Next, looking at FIG. 4, in order to achieve this purpose, the user state (ie, leg direction and leg motion) detector 500 generally includes the accelerometer 152, the real-time clock 505, and the surroundings. The light detector 510, the processor 515 for calculating the user's activity (eg, body orientation, body movement and activity level), and the stimulus current supplied by the constant current source 410 of the TENS device 100, the processor 515. It is provided with a controller 520 for changing according to the determination by.

When the TENS device is firmly attached in place on the upper part 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 limbs. When the TENS device 100 and the lower limbs 140 are tightly and mechanically coupled, the movement of the user's lower limbs can be accurately measured by the accelerometer 152. Such tight mechanical coupling is preferably established by the strap 110 described above. Alternatively, the tight mechanical coupling may be established by other means (eg, a flexible band wrapping the TENS device). If desired, a tension gauge 109 (FIG. 1) may be provided on the strap 110 to ensure that a tight mechanical bond has been established between the TENS device 100 and the calf upper 140.

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

The leg direction and leg movement components measured by the user state (ie, leg direction and leg movement) detector 500 of the present invention can contribute to determine the sleep-wake state of the user individually or collectively. .. In one of the preferred embodiments of the present invention, the processor 515 of the TENS device 100 measures the orientation of the user's calf, which is highly correlated with the orientation of the user's body. More specifically, an upright body orientation is generally a sure sign that the user is awake, and a recumbent orientation suggests a resting state (eg, what happens during sleep). Regular and firm body movements are likely to be the result of daytime (ie, awake) user activity, and quiet or low-level unconscious movements are nighttime (ie, during sleep). It is likely that it is. The interaction of body orientation and level of movement can also be useful in identifying a user's sleep-wake state (ie, thereby expanding the sleep-wake state classification). Specifically, lying body orientation and low levels of physical activity are generally good indicators of a user's sleep.

In addition, the real-time clock 505 of the user state (ie leg direction and leg movement) detector 500 obtains the sleep-wake state obtained by the aforementioned analysis of leg direction and leg movement data at any given time of the day. To further improve the classification results, it is possible to assign an important a priori probability of sleep-wake state (ie, the user is likely to be asleep at 3 am and asleep at 4 pm). It is unlikely that you are there). In a preferred embodiment of the invention, the threshold for classifying the user's body orientation as lying is tightened to reflect the low a priori probability of sleep during certain daytime periods. obtain.

In another embodiment of the invention, the output from the ambient light sensor 510 is used to improve the sleep-wake classification results. Whether the ambient light sensor 510 is illuminated or not in the user's environment to reflect the a priori probability that the user is more likely to be asleep in a darker setting than in a brightly illuminated setting. Can be used to determine. Therefore, the thresholds for classifying the user's body position and exercise level can be adjusted to reflect the a priori probability of sleep.
Skin Surface Detector In one of the preferred embodiments of the present invention, the TENS device 100 may include a skin surface detector to ensure that the TENS device 100 is firmly mounted on the user's skin.

More specifically, when the TENS device is worn by the user, the measurement of direction and motion from the accelerometer 152 in the TENS device 100 is associated only with the user's direction and motion. In a preferred embodiment, a skin surface detector 521 is provided to determine if the TENS device 100 is firmly placed on the upper part of the user's calf and how long it is firmly placed. Next, looking at FIG. 5, in a desirable embodiment, the skin surface detector 521 may be provided inside the TENS device 100. More specifically, in one of the preferred embodiments of the present invention, by closing the switch 220, a voltage of 20 volts from the voltage source 204 is applied 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 voltage to the voltage divider circuit formed by the resistors 208 and 206. To do. More specifically, when the TENS device 100 is on the skin of the user, represents a system equivalent circuit 260 of reality shown in FIG. 5, the anode voltage _V a 204 can be sensed by the voltage divider resistors 206 and 208 .. The cathode voltage measured from the amplifier 207 is not zero, but a value 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 the real system and the cathode voltage from the amplifier 207 becomes zero.

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

Second, 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, and the processor 515 of the TENS device 100 has data from the accelerometer 152. However, it recognizes that it cannot 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 responds appropriately (eg, warns the user). be able to. In this regard, the skin surface detector 521 indicates that the TENS device 100 is on the user's skin, and when the accelerometer 152 is snugly coupled to the user's lower limbs, the data from the accelerometer 152 is in the user's leg direction. And understand that it can represent the user's leg movements. 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 snugly coupled to the user's lower limbs, the data from the accelerometer 152 will be in the user's leg direction and It does not represent the user's leg movements.
Processing Accelerometer Data In one of the preferred embodiments of the present invention, the user state (ie, leg direction and leg motion) detector 500 obtains accelerometer data from the accelerometer 152 to obtain user activity (eg, body direction, etc.). It is equipped with a processor 515 for calculating (level of body movement and activity).

More specifically, in one of the preferred embodiments of the invention, the processor 515 has a high degree of correlation with body orientation and thus exhibits a user's lying state (thus indicating a user's sleep-wake state). Accelerometer data from accelerometer 152 was used to measure the user's leg orientation and the user's leg movement, which also indicates the user's sleep-wake state and leg movement activity level, and these user's legs. Extend sleep quantification using orientation and user leg movement determination.

More specifically, the processor 515 uses the user's "raised" (ie, the angle of the lower leg with respect to the horizontal plane) and the "rotation" of the leg (ie, the angle of rotation of the lower leg around its own axis). Accelerometer data from accelerometer 152 is used to measure two distinct aspects of leg orientation.

The processor 515 also includes "net activity" (the magnitude of exercise-related acceleration averaged within a one-minute time window) and "leg movement" (ie, what happens during sleep). Accelerometer data from accelerometer 152 is used to measure two distinct aspects of leg movement, such as (a short-term event known, but not apparent in net activity). Some leg movements with large leg rotations can be further classified as "body rotation events" (such as those that occur when turning over in bed).

In a preferred embodiment of the invention, a processor 515 for calculating user activity (eg, body orientation, 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. The "momentary" time scale is then defined as 0.1 seconds. The axes (x, y, z) 50Hz data in are separately averaged over each _{instant, A x (t), A} y (t), and _A z (t) and 10Hz low noise data expressed Bring a stream.

Accelerometer data A _x (t), A _y (t), and A _z (t) take longer to capture a steady prediction of the Earth's gravity along each axis (x, y, z). It is used to form a characteristic that is the average of A _x (t), A _y (t), and A _z (t) across a window (eg, a one minute time window). These properties are used to detect leg orientation (ie, leg ridges and leg rotations).

In addition, accelerometer data A _x (t), A _y (t), and A _z (t) are static gravity in a high pass filter to separate the acceleration components brought about by leg movement. Ingredients are removed. The -3dB point of the high pass filter is at 0.5Hz. Accelerometer data filtered through high frequencies

,

,and

It is expressed as.
Detection of Leg Rise In one of the preferred embodiments of the present invention, the user state (ie, leg direction and leg movement) detector 500 is configured to detect leg ridge.

More specifically, the leg ridges used by the present invention to determine "body orientation" for sleep monitoring purposes are TENS devices by processor 515 of the user status (ie, leg orientation and leg movement) detector 500. It is calculated based on the measurement data from the accelerometer 152 when the 100 is located on the upper part 140 of the user's calf (FIG. 1). Next, looking at FIG. 6, in a preferred embodiment, the accelerometer 152 is located on the circuit board 151 of the TENS circuit housed inside the compartment 102, whereby the TENS device is located above the user's calf. When placed, the directions of the three axes of the accelerometer shown in 153 of FIG. 6 (ie, x-axis, y-axis, z-axis) are known, fixed in association with the lower leg, and y-axis. Are arranged vertically along the vertical axis of the lower leg, the x-axis is arranged in a close battle direction with respect to the surface of the lower leg, and the z-axis is arranged perpendicular to the y-axis from the surface of the lower leg. It faces in the radial direction.

The calf of an upright and stationary user or a user seated with their feet on the ground should be upright. As a result, the y-axis acceleration of the accelerometer 152 has a value of about -1 g due to the gravity of the earth 154 (FIG. 6), where g is the gravity acceleration of the earth. 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 on the upper part of the calf (possible placement position), the accelerometer axis rotates as shown in 155 of FIG. In this case, the upright and stationary user will have an acceleration value of about + 1g measured along the y-axis. In contrast, a resting lying user sleeping with his legs 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 lying down.

Next, looking at FIG. 7, the gravity vector of the earth is downward, and the elevation angle θ (172) represents the angle between the positive direction (174) of the y-axis of the accelerometer and the true horizontal plane (170). In a preferred embodiment, the threshold for y-axis acceleration measurements is set to 0.50 g from the horizontal plane corresponding to the angle of the leg ridge θ≈30 °, but other thresholds can also be used and the user sleeps. You may have the freedom to adjust this value in order to better distinguish between the behavior of and the behavior of arousal.

In general, the acceleration measured along the y-axis should include not only the projection of gravity on the y-axis, but also the contribution from motion, as in the following equation.
A _y (t) = ± sin | θ (t) | + m (t) [Unit is g]
Here, t is time and m (t) is the contribution of leg movement. The particular ± sign relies on the placement of the TENS device at the upper calf 140 and is fixed for each placement. The motor component m (t) is considered "noise" in situations where leg ridges are determined, and the average over a sufficiently long time window should be zero.

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

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

Step 2. We define a non-overlapping time window of length N called an "epoch". The time at the end of each epoch is represented by T. In a preferred embodiment, accelerometer data (in standard Earth gravity units g) are segmented into epochs (ie, a one minute time window). At a sampling rate of 10 Hz for accelerometer data, the epoch length is N = 600. Based on the sample of each epoch, the mean values A _y , _T and the standard deviation S _{Y, T of the} mean values are calculated.

Step 3. Let θ _T = sin ^-1 _{Ay, T.} A value of θ _T ≈ θ ₀ may result in unstable switching of the leg raised state. In order to reduce this, the hysteresis band θ ₀ ± θ _H is defined. In a preferred embodiment, the hysteresis parameter θ _H is set to 2.5 °, but other values are possible (but should be small compared to θ ₀ ). In a preferred embodiment, instead of calculating sin ^-1 for all epochs, instead the angle threshold is converted to a unit of acceleration, i.e. two thresholds Α _± = sin (θ ₀ ± θ _H ). By calculation, _{Ay and T} will be compared against them.

Step 4. The ability of the hysteresis band to prevent unstable switching of the raised leg state depends on the amount of noise in the data characterized by SEY _{, T,} which is the standard deviation of the mean values _{Ay, T.} To clarify 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} with the threshold A _± . However, the processor 515 compares the "confidence intervals" A _{y, T} ± ηSE _{Y, T} with the threshold A _± instead of comparing the mean values A _{y, T} itself with the threshold A _± . More specifically, for each epoch, if the previous raised state was lying down, the processor 515 of the user state (ie, leg direction and leg movement) detector 500 could classify the next state as upright. , [| A _{y, T} | -ηSE _{Y, T} ]> A ₊ . In order to classify the next state as lying down when the previous raised state is upright, the processor 515 of the user state (ie, leg direction and leg movement) detector 500 may use [| _{Ay, T} | + ηSE _{Y. , T} ] <A ₋ . In the preferred embodiment, η = 3, but other values are possible.
Instantaneous activity In one of the preferred embodiments of the present invention, the processor 515 of the user state (ie, leg direction and leg motion) detector 500 is configured to detect instantaneous activity.

More specifically, when the TENS device 100 is worn on the user's upper calf 140, the user's activity will be captured by the accelerometer 152 of the TENS device. 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's gravity. To separate contributions from leg movement, processor 515 of the user state (ie leg direction and leg movement) detector 500 receives the instantaneous data vector A (t) = [A _x (t) before further processing. , A _y (t), A _z (t)] is filtered to pass high frequencies.

The acceleration components for each axis of the accelerometer contain unique and useful information for analyzing body movements, but the magnitude of the acceleration vector called "instantaneous acceleration".

But,

It is defined as and is commonly used to quantify the overall activity associated with exercise. In a preferred embodiment of the invention, the processor 515 of the user state (ie, leg direction and leg motion) detector 500 has this instantaneous acceleration.

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

Instead of 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 of the preferred embodiments of the present invention, the processor 515 of the user state (ie, leg direction and leg motion) detector 500 may be configured to detect leg motion.

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 between walking, running, climbing stairs, etc. is there. In a preferred embodiment, leg movement (LM) is in a manner consistent with the detection of periodic leg movement (PLM) as defined in the clinical literature (Bonnet et al., 1993 and Zucconi et al., 2006). Although calculated, other techniques 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 performed by processor 515 of the user state (ie, leg direction and leg movement) detector 500 in the following manner.

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

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

To calculate.
Step 3. The IAS is updated as follows for each time. IAS = False,

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

If so, set IAS = False. The two thresholds used in this way are those that simply implement hysteresis to prevent rapid switching of 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. Therefore, the continuous time interval of IAS = true, surrounded by the period of IAS = false, constitutes the leg movement (LM) period. However, if the separation of adjacent periods when the IAS is true is less than 0.5 seconds, this short period when the IAS was false is ignored.

The top panel (810) in FIG. 8 shows an example of a leg movement (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 them are instantaneous accelerations.

Is. The vertical line 813 is

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

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

Is below the second threshold 816 for 0.5 seconds or more for the first time, so that the LM period ends. The final result is an LM period with 89 instantaneous periods (ie 8.9 seconds).
Body Rotation Detector In one of the preferred embodiments of the present 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 specifically, when the TENS device 100 (FIG. 9) is worn on the lower part of the user's leg (ie, upper calf 140) and the user is in a lying position, the accelerometer 152 is in its x-z plane. It will sense the projection of gravity. The angle φ between the device's x-axis and the gravity vector-g can be calculated based on the projected gravity values on the x-axis and z-axis. The axis z'matches the "thumb" orientation of the user's leg to which the TENS device 100 is attached. When the TENS device is firmly positioned at the bottom 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 legs (defined as the direction indicated by the big toe, i.e. the z'axis) and the Earth's gravity (z'axis). When measuring from the x'axis to the x'axis, the angle values remain the same. The relationship between β and φ can be easily derived as shown in the following equation.

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 short-term increase in activity, classified as leg movement (LM), is associated with a large change in rotation angle φ measured by the TENS device 100. A sufficiently large rotation is unlikely to include only the legs and should represent a full-body turnover when sleeping, for example from left to right, or from back to left or right. .. Therefore, some leg movements (LM) can be classified as "body rotation events".

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

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

Step 2. Before and after each LM period, A (t) (not filtered through high frequencies) on each axis to obtain A _x (t), A _y (t), and A _z (t). Get the instantaneous value 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 inverse tangent function atan2 returns an angle within the range −180 ° <φ (t) <180 °, i.e. the result within all four possible quadrants.

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

Step 5. Compare the absolute value | Δφ | with the threshold. 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. Acceleration values A _x (t), A _y (t), and A _z (t) are plotted on 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 ridges are in a recumbent state. In contrast, _Ax (t) and _Az (t) show outstanding activity, especially between times 30 and 70. In addition, the steady-state value of A _x (t) changes from + 1 g (before the LM period) to -1 g (after the LM period), suggesting a body rotation event.

The bottom panel (830) of FIG. 8 shows the calculation of the elevation angle θ (833) and the rotation angle φ (834) for each moment. Throughout the event, elevation θ≈0 is consistent with a recumbent ridge at the bottom of the leg. In contrast, the rotation angle φ changes 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 (rightward) rotation of the whole body.

These body rotations may be reported directly to the user to inform them about their sleep patterns. In addition, body rotation events can be short-lived and activity-related increases in activity epoch mean cannot be apparent, so the epoch does not have to be classified as arousal. Rolling over in bed may not represent arousal and represents a fleeting, restless sleep. This novel technique for detecting body rotation by assessing changes in rotation angle associated with short-term leg movement (LM) is independent of body rotation from leg movement related to body rotation. It allows for differentiating leg movements and thus provides a more detailed description of sleep patterns that are useful in clinical diagnosis.

In another preferred embodiment, to improve robustness to noise, instead of using a single instantaneous A (t) before and after the LM to calculate the angle φ, how many before and after the LM. The mean or median of A (t) over that moment is used.

In another preferred embodiment, the body rotation detection algorithm is implemented by processor 515 of the user state (ie, leg direction and leg movement) detector 500 using the angle change Δβ in the following manner. Consider a person lying on his back with a TENS device placed on his right leg. When the toes are pointing vertically upwards, β = 0 when the TENS device is placed on either leg, and β increases with counterclockwise (CCW) rotation, thus leg rotation. Recall that the range of positions is usually -80 ° ≤ β ≤ 0 °. Any change Δβ in angle that remains within that range will probably not be associated with body rotation. In contrast, the change in angle from within that range to outside that range Δβ is often associated with body rotation. Thus, the threshold for detecting body rotation can be adjusted using the angular change 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 rotation angle β of the leg before and after the movement of the leg (LM) and the sign of the angle change Δβ over the movement of the leg (LM) are the signs of the rotation detector of the body. Can be used to improve performance.
Static body rotation position detector In one of the preferred embodiments of the present invention, the processor 515 of the user state (ie leg direction and leg movement) detector 500 is to function as a static body rotation position detector. Can be configured in.

More specifically, users with sleep apnea are advised not to sleep on their backs.
Since the range of rotation of human hip movements is limited, the position of rotation of the legs is highly correlated with body position, for example, when sleeping on the back, the toes of both feet are horizontal to varying degrees. It is unlikely that it will point upwards, exactly in the direction of the horizontal plane, and it will not be possible to point downwards below the horizontal plane. This observation, along with the placement of a novel TENS device above the user's calf, enables an innovative reinforcement for sleep analysis.

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

,

,and

Is introduced above in the paragraph entitled "Detection of leg ridges". Since it is sufficient to report the time spent sleeping on the back with a resolution of 1 minute, these epoch-averaged acceleration values can be used advantageously 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 unprocessed (ie, unfiltered high pass filter) acceleration averaged over the epoch T. β _T = the angle of the toes with respect to the vertical. The relationship between φ _T and β _T relies on the rotational arrangement of the TENS device at the upper part of the user's calf, represented by α. 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 upper 140, and thus the TENS device is on the user's leg. As long as the angle is constant.

Next, looking at FIG. 9, the double prime coordinate system (that is, x ", y", z ", which is not seen in FIG. 9 because y" extends below the leg axis) has gravity. It is fixed to the earth along the vertical axis, is a single prime coordinate system (ie x', y', z', and y'extends below the leg axis, so FIG. 9 shows. (Not seen) is fixed to the leg and has no prime (ie x, y, z, y is not seen in FIG. 9 because it extends below the leg axis). Is

and

Is fixed to the TENS device that measures. The earth coordinate system has a z "axis along the vertical, the leg coordinate system has a z'axis in the direction of the toes, and the leg rotation angle β is between the x" axis of the earth and the x'axis of the leg. The angle. The angle α of the TENS device is the position of the TENS device on the leg as measured from the x'axis of the leg. Using accelerometer axis information in TENS devices and standard geometric techniques, including the identification of similar triangles, it can be easily associated by β = 180-α-φ. It will be obvious to the trader. Therefore, in each epoch, these angles are easily related by β _T = 180-α-φ _T.

In a preferred embodiment, the following simple procedure is used by processor 515 of the user state (ie leg direction and leg movement) detector 500 to determine if the user is lying on his back by estimating the angle β. To.

Step 1. The user places a TENS device on his lower limbs, neatly secures the strap 110 around the upper calf 140, lays down with his legs nearly horizontal, and stays still with his toes pointing vertically upwards.

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

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

It is self-evident to presume

Is estimated from accelerometer data acquired during the period when the toes are facing up. To facilitate the calculation, this difference,

Put in the range of, that is,

If so, subtract 360 °,

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

,

Used to calculate. To facilitate comparison with the threshold, put this difference in the range -180 ° <β _T ≤ 180 °, i.e. if β _T > 180 °, subtract 360 ° and β _T ≤ -180 °. For example, add 360 °.

Step 5. Define a range of β _T values that corresponds to a user lying on his back or sleeping. In the preferred embodiment, all epochs with −80 ° <β _T <80 ° are classified as “on their backs”. Since this range is symmetric, this algorithm is valid no matter which leg the TENS device is placed on. Avoiding ± 90 ° by 10 ° excludes values that can occur when the user is lying 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 located. 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 down with low activity, several sets of time, for example minutes. The TENS device notifies the user when lying on his back beyond. This instruction can be, for example, the 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 have slept, that is, lying down with a low activity, the time (minutes) of the portion where the user is determined to be lying on his back is determined. This percentage is reported to this user, for example using a smartphone 860.
Illustrative Operation In one of the preferred embodiments of the present invention, a TENS device 100 including a user state (ie leg direction and leg motion) detector 500, its processor 515, and its controller 520 is shown in the flow diagram of FIG. It is programmed to work as shown.

More specifically, when the TENS device 100 firmly attached to the user's upper calf 140 is turned on, the user state (ie leg direction and leg movement) detector 500 accelerates as shown in step 902. Data is collected from a total of 152, the real-time clock 505 and the ambient light detector 510. In addition, the skin surface detector 521 confirms that the electrode arrangement 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 on the user's upper calf 140). Make sure it is firmly attached).

As shown in step 906, the processor 515 analyzes the data from the accelerometer 152, the real-time clock 505 and the ambient photodetector 510.
Processor 515 determines whether the user is sleeping by determining the leg ridge direction of the user, as shown in step 908, and comparing the elevation angle with a threshold (ie, "threshold 4"), as shown in step 910. Judge whether or not.

When the processor 515 determines that the user is sleeping, it determines the leg activity of the user, as shown in step 912.
If the user's leg activity is compared to a threshold (ie, "threshold 1") as shown in step 914 and the user's leg activity is less than the threshold 1, processor 515 will perform the user as shown in step 916. Judges that he is sleeping peacefully.

Processor 515 also compares the user's leg activity (obtained in step 912) with another threshold (ie, "threshold 2"), as shown in step 918, and when the user's leg activity exceeds threshold 2, Processor 515 determines that the user is moving his leg excessively, as shown in step 920.

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

Further, the processor 515 indicates that the user's leg rotation direction obtained in step 922, the accelerometer data analysis obtained in step 906, and the user's limbs and toes obtained in step 928 are upward. To determine the classification of the user's position as shown in step 930.

Processor 515 then characterizes the user's position, such as "backward", "(left / right) sideways" or "downside down", as shown in step 932.
The information derived in steps 916, 920, 926 and 932 is then utilized by processor 515 to analyze the user's sleep period, as shown in step 934. The results of this sleep analysis (as determined in step 934) may then be displayed (as shown in step 936) and provide feedback to the user or user's caregiver (as shown in step 938). And / or (as shown in step 940) may be used to instruct controller 520 to adjust the stimulus current supplied by the TENS device 100.
Modifications of the Desirable Embodiment 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 orientation includes a state of leg ridge and leg rotation and a change in the state of leg ridge and leg rotation. The TENS stimulator can be pre-programmed to change its behavior in response to the detected leg activity and leg position of the user during bedtime. In addition, leg orientation and leg activity are used to assess sleep quality and posture during sleep, all of which are important embodiments 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 alleviate excessive leg movements that cause confusion for sleep.

The present invention can be realized without a nerve stimulating function. Body movements and positions can be monitored and quantified using the present invention without the need for nerve stimulation. The monitoring device may be placed in another position, such as the upper part of either limb.

Moreover, many additional changes in the arrangement of details, materials, steps and parts described and illustrated herein to illustrate the properties of the invention by those skilled in the art are within the principles and scope of the invention. Please understand that it can be done while still staying.

Claims (15)

A device for providing transcutaneous electrical nerve stimulation (TENS) therapy to users.
With the housing
A mounting unit for providing a mechanical connection 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 movement of the user's body and the direction of the body,
It comprises a reporting unit for providing feedback to the user based on the perceived body movement and body orientation of the user.
Direction of the body, Ri rotational direction der in a plane perpendicular to the longitudinal axis of the body the user,
The sensing unit uses data from the electromechanical sensor and the direction of rotation is estimated by analyzing the output of the electromechanical sensor.
The output of the electromechanical sensor, Ru average der projections of the earth gravity to a plane perpendicular to the longitudinal axis of the body the user device. The device of claim 1 , wherein the analysis comprises the step of estimating an angle formed by said average of said projections of earth gravity. The device of claim 2 , wherein the calibrated body rotation direction is the estimated angle obtained with reference to a rotation direction angle in a known body direction. The device of claim 3 , wherein the known body orientation is such that the user is lying on his back with his big toe facing up. A device for providing transcutaneous electrical nerve stimulation (TENS) therapy to users.
With the housing
A mounting unit for providing a mechanical connection 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 movement of the user's body and the direction of the body,
It comprises a reporting unit for providing feedback to the user based on the perceived body movement and body orientation of the user.
The sensing unit uses data from the 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 the state of the user's body direction using an analysis unit that operates in the measurement of the earth's gravity acceleration, and the state of the user's body direction is upright. Or including one from a set of lying down,
The sensing unit determines the 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 the target region, the movement. State is considered active and
The reporting unit calculates the cumulative time that the user's body orientation is lying down.
A device in which the reporting unit calculates the distribution of the difference between the angles of the user's body in the rotational direction. The device according to claim 5 , wherein the reporting unit calculates the cumulative time when the user's motion state is not active and the user's body orientation is lying down. The device according to claim 5 , wherein when the user's body direction is lying down, the angle of each pair is measured immediately before and immediately after the user's motion state is active. The device of claim 5 , wherein the reporting unit calculates the duration when the user's calibrated body rotational angle is within the target range. The device according to claim 8 , wherein the target range has nothing to do with the instruction of the limbs. The device of claim 8 , wherein the target range relies on limb instructions. The device of claim 8 , wherein the feedback is activated when the user's calibrated body rotation direction is within the target range. The device of claim 5 , wherein the feedback is activated when the distribution meets a set of criteria. 12. The apparatus of claim 12 , wherein the set of criteria is the proportion of the contrast having a value above a threshold greater than a predetermined proportion. The device of claim 8 , wherein the feedback is activated when the duration exceeds a threshold. A device for providing transcutaneous electrical nerve stimulation (TENS) therapy to users.
With the housing
With a mounting unit to provide a mechanical connection between the housing and the user's legs,
A stimulation unit for electrically stimulating at least one nerve of the user,
A sensing unit for sensing the leg direction and leg movement of the user, wherein the step of sensing the leg direction of the user includes a step of determining the leg ridge and leg rotation of the user, and the leg movement of the user is performed. The sensing unit comprises the step of determining the user's net activity and leg movement.
A device including a controller for adjusting the stimulation unit based on a determination by the sensing unit.

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