Patent Publication Number: US-7211053-B2

Title: Selectively applied wearable medical sensors

Description:
This is a Continuation of application Ser. No. 10/043,380, filed Oct. 26, 2001 and issued as U.S. Pat. No. 6,755,795. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to sensors used in the electrical treatment and monitoring of human and animal bodies. More specifically, the invention relates to wearable garments that allow sensor devices to be pressed selectively against the skin of the wearer when it is desired to obtain medical information or to apply treatment by contact with the surface of the skin. 
     2. Description of the Invention 
     Sensing and treatment devices for contacting the surface of the skin are well-known in the art. It is also well-known that such devices require tight-fitting, e.g. elevated unit pressure, contact with the skin. However, the incorporation of such sensors into wearable garments that provide for applying sensors to the skin of a wearer with selective and/or variable pressure, is not well-known. 
     In the prior art, sensors are either adhered directly to the skin of the wearer using well-known types of adhesive materials or, they are tightly strapped to the user&#39;s body using suitable straps or bands having buckles or other clasping mechanisms adapted to the purpose. Such prior art apparatus for affixing sensors to the skin of a user do not take the user&#39;s comfort into consideration by allowing the pressure of the sensor against the skin to be increased easily only when the sensor is in use. 
     The present invention overcomes these problems and limitations of the prior art by allowing sensors to be pressed against the skin of a wearer selectively, only when needed or desired. The sensors are mounted on the inside of a wearable garment, and the garment incorporates circumscribing bands that can be reduced in diameter, selectively, to press the sensors against the skin of one wearing the garment. 
     SUMMARY OF THE INVENTION 
     The present invention discloses a wearable garment that incorporates one or more skin-contacting sensor devices positioned to contact the skin surface of a user wearing the garment. The wearable garment of this invention incorporates one or more bands of flexible material that circumscribe portions of the wearer&#39;s body with at least one sensor device positioned between the band and the wearer. The circumference of the band can be shortened from a first dimension, which loosely circumscribes the desired portion of the wearer&#39;s body, to a second, lesser dimension, which securely presses the sensor into contact with the wearer&#39;s skin. 
     In accordance with this invention, the band may be tightened about the wearer&#39;s body either by drawing the ends of a loop about the body in the nature of a drawstring or by shrinking the overall length of the material of a continuous loop as by passing an electrical current through a continuous loop made of shape Memory Alloy Wire. In this regard, the band may be loosely incorporated into the body of the garment in the well-known manner of a drawstring or, the band may be integrated into the body of the garment as by forming a desired portion of the fabric material from different fibers such as fibers comprising Shape Memory alloy. To utilize the electrically responsive shrinkage characteristics of shape-memory alloy material in a convenient manner, the garment may be provided with means for supporting or otherwise carrying with it, a portable electrical power supply such as a battery. 
     Further in accordance with this invention, it may be noted that any treatment or monitoring equipment that relies upon the sensors carried by the wearable garment, may incorporate internal features such as a programmable microprocessor to activate a band formed of shape memory alloy, at a predetermined rate or in accordance with a predetermined schedule. 
     These and other and further features and advantages of this invention will be made more apparent to those having skill in this art, by reference to the following specification considered in conjunction with the accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front plan view of a wearable garment in accordance with this invention, incorporating two separate drawstrings positioned to apply two separate sensors to the skin of a wearer; 
         FIG. 2  is a pictorial representation of an alternative embodiment of an electrically activatable band usable in accordance with this invention in lieu of the drawstring of  FIG. 1 ; and, 
         FIG. 3  is a front plan view of an alternative embodiment of a wearable garment in accordance with this invention, incorporating constriction bands formed of a shape-memory material that is constrictable in response to the flow of electricity therethrough. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENT 
     In the following description, for purposes of explanation rather than limitation, specific details are set forth such as the particular architecture, interfaces, techniques, etc., in order to provide a thorough understanding of the present invention. For purposes of simplicity and clarity, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail. 
     Referring now to  FIG. 1  of the drawings, a wearable shirt garment  10  in accordance with this invention may be seen to comprise a wearable body structure  12  having a first constriction band  14  coupled to the body  12  in the form of a drawstring circumscribing the chest area of a wearer, and a second constricting drawstring  16  circumscribing a wrist area. Shown in dotted lines representing a position on the interior (invisible) surface of garment  10 , a first sensor device  18  is positioned so that it will lie between the band  14  and the chest skin of one wearing the garment  10 . A second sensor  20  is similarly positioned to lie between band  16  and the wrist skin of a wearer. 
     It should be understood readily by those having skill in this art, that the number and positioning of the bands  14 ,  16  and the sensors  18 ,  20  is illustrative only, and other or different sensors, or different number of sensors, in other or different locations may be incorporated into this or any differently shaped garment without departing from the spirit and scope of this invention. For example, in the absence of any desire for a sensor in a wrist area, the garment may be made essentially sleeveless in form, if desired. Similarly, the garment may assume other forms, such as, for example, trousers rather than a shirt or vest, or even, perhaps, a simple wrist or arm band. 
     Bands  14 ,  16  define loops positioned so as to substantially circumscribe desired portions of the anatomy of the wearer of the garment  10  in a loose-fitting loop, and they are configured to have a first circumferential loop dimension that circumscribes the wearer&#39;s body in a loose, non-confining fit. In the embodiment illustrated in  FIG. 1 , bands  14 ,  16  are coupled to the body structure  12  in the manner of a drawstring that is looped around the anatomy of a wearer when the body structure is being worn. Further, the bands are provided with free ends  22 ,  24 , that can be drawn in opposite directions to reduce the circumferential dimension of the loop from a first value to a second value that is less than the first. When the circumferential dimension of the loop is reduced in this way, the corresponding band constricts the body of the wearer of garment  10 , and presses the corresponding sensor device  18 ,  20  against the wearer&#39;s skin. 
     As mentioned earlier herein,  FIG. 2  illustrates an alternative form of constriction band  26 , having the form of a continuous, or closed, loop formed of shape memory alloy fibers having a first loose-fitting circumferential dimension. In the well-known manner of shape memory alloy materials, the first circumferential dimension of loop  26  may be reduced to a lesser second dimension so as to constrict an interposed sensor device  18 ′ into contact with a wearer&#39;s body in accordance with this invention, by passing an electrical current, from a battery  28 ′ for example, through the material of the loop. If desired, this embodiment of the invention may incorporate a suitable microprocessor  30 ′ coupled with a source of electrical power such as battery  28 ′, to control the application of electrical current to the band. In this manner, constriction of the band  26  may be made to take place periodically or in association with any desired external activity, such as the activation of an apparatus associated with use of sensors such as sensor  18 ′, shown in  FIG. 3 . 
     Referring to  FIG. 3 , bands  14 ′,  16 ′ can be integrated with the fabric of a wearable structure using conventional methods and can be of any natural or man made material sufficient to accomplish operations consistent with the requirements of the embodiments of the present disclosure, including, for example, Nitinol. Bands  14 ′,  16 ′ can also have different arrangements suitable to operatively interact with different sensors  18 ′,  20 ′ associated with the wearable structure in different ways, and so as to accommodate different applications. 
     The fabric of the garment body structure  12  may be any suitable material usable for garments, consistent with the requirements of the embodiments of the invention described herein. Similarly, the material of the bands  14 ,  16  may be any suitable flexible material consistent with this disclosure. 
     While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the present invention. In addition, many modifications may be made to adapt to a particular situation and the teaching of the present invention without departing from the central scope. Therefore, it is intended that the present invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out the present invention, but that the present invention include all embodiments falling within the scope of the appended claims. 
     Referring to  FIG. 3 , bands  14 ′,  16 ′ can be integrated with the fabric of a wearable structure using any of a variety of conventional methods for weaving, sewing or knitting and can be of any natural or man made material sufficient to accomplish operations consistent with the requirements of the embodiments of the present disclosure, including, for example, Nitinol. Bands  14 ′,  16 ′ can also have different configurations suitable to operatively interact with different sensors  18 ′,  20 ′ associated with the wearable structure so as to accommodate different applications.