Electro active compression bandage

Abstract

The proposed device includes two segments adapted to enclose a body part in a form-fitting manner. Each segment contains an electroactive-material-based actuator, which is adapted to receive an electrical control signal and in response thereto adjust the actuator's morphology, so as to cause the segment to apply a basic pressure profile to the body part. A pressure transition is adapted to redistribute the basic pressure profiles between the first and second segments. A control signal in respect of the first segment causes the pressure transition system to apply a first adjusted pressure profile to at least part of the second portion of the body part, and vice versa, a control signal in respect of the second segment causes the pressure transition system to apply a second adjusted pressure profile to at least a part of the first portion of the body part.

1 . A device for exerting an external pressure to a human body part, the device comprising at least two segments of which a first segment is adapted to at least partially enclose a first portion of the body part in a form-fitting manner and a second segment is adapted to at least partially enclose a second portion of the body part in a form-fitting manner, each of the at least two segments containing an electroactive-material-based actuator which is adapted to receive an electrical control signal and in response thereto adjust the actuator's morphology so as to in the absence of any intermediate component between the actuator and the body part cause the segment to apply a basic pressure profile to the body part in direct response to the electrical control signal; a pressure transition system which is adapted to be positioned between a first surface defined by the first and second segments and a second surface defined by the body part, the pressure transition system extends over the first and second portions of the body part when the device is fitted on the body part, and the pressure transition system has such mechanical properties that the pressure transition system is adapted to redistribute the basic pressure profiles between the first and second segments, in such manner that
 a control signal in respect of the first segment causes the pressure transition system to apply a first adjusted pressure profile to at least a part of the second portion of the body part,   a control signal in respect of the second segment causes the pressure transition system to apply a second adjusted pressure profile to at least a part of the first portion of the body part, and   each of the first adjusted pressure profile and the second adjusted pressure profile being different from each of a first basic pressure profile of the first segment and a second basic pressure profile of the second segment.   
     
     
         2 . The device according to  claim 1 , wherein
 a change of said morphology is instigated by the electrical control signal, and   each of said actuators is adapted to maintain a thus changed morphology on the basis of an electrical control signal supplying charge replenishment to the actuator.   
     
     
         3 . The device according to  claim 1 , wherein the pressure transition system is adapted to be positioned between the first and second segments when the device is fitted on the body part. 
     
     
         4 . The device according to  claim 1 , wherein the pressure transition system has a low-friction surface towards the first and second segments, and said surface is adapted to allow a smooth tangential movement of the first and second segments relative to the pressure transition system. 
     
     
         5 . The device according to  claim 1 , wherein the first and second segments are arranged such that a portion of the first segment covers a portion of the second segment when the device is fitted on the body part. 
     
     
         6 . The device according to  claim 1 , wherein the pressure transition system comprises a number of collapsible ribs adapted to extend along a general central axis of the body part and be positioned between at least one of said segments and a particular portion of the body part when the device is fitted on the body part, an actuator of each of said at least one segment is adapted to cause a tangential movement of said at least one segment relative to the body part, and the collapsible ribs are adapted to fold in response to said movement such that when folded the ribs exert a radial pressure on the particular portion of the body part. 
     
     
         7 . The device according to  claim 1 , wherein the pressure transition system comprises at least one flexible chamber adapted to be positioned between at least one of said segments and a particular portion of the body part when the device is fitted on the body part, an actuator of each of said at least one segment is adapted to cause a tangential movement of said at least one segment relative to the body part, and the at least one flexible chamber is adapted to transform said movement into a resulting radial pressure on the particular portion of the body part. 
     
     
         8 . The device according to  claim 7 , wherein the at least one flexible chamber has an elastic wall of an anisotropic material, the at least one chamber is adapted to be arranged relative to the body part when the device is fitted on the body part such that the at least one chamber is relatively stretchable in a circumferential direction of the body part and relatively stiff in a direction along a general central axis of the body part. 
     
     
         9 . The device according to  claim 1 , wherein the pressure transition system comprises a number of protrusions adapted to be positioned between at least one of said segments and a particular portion of the body part when the device is fitted on the body part, said protrusions are adapted to convert the basic pressure profile of said at least one segment into a nonuniform pressure profile to the particular portion of the body part. 
     
     
         10 . The device according to  claim 9 , wherein said protrusions comprise at least one rigid rib adapted to extend along a general central axis of the body part and be positioned between at least one of said segments and a particular portion of the body part when the device is fitted on the body part, and a respective peak pressure ridge of the nonuniform pressure profile is defined by a positioning of each of the at least one rib relative to the body part. 
     
     
         11 . The device according to  claim 1 , wherein the device comprises a control unit adapted to produce a respective control signal to each of said segments, and the control unit is adapted to vary the control signal over time to implement a treatment profile with respect to the body part. 
     
     
         12 . The device according to  claim 1 , wherein the treatment profile involves applying gradually varying pressure profiles to the body part via said segments. 
     
     
         13 . The device according to  claim 11 , wherein the treatment profile involves producing repeated cycles of variations between relatively high and relatively low basic pressure profiles by means of each of said segments. 
     
     
         14 . The device according to  claim 11 , wherein the treatment profile involves producing quasi-static pressure profiles by means of said segments. 
     
     
         15 . The device according to  claim 1 , wherein the pressure transition system comprises a number of air channels adapted to allow air to pass to the body part. 
     
     
         16 . The device according to  claim 15 , wherein the air channels are adapted to exchange air between the body part and a local environment outside the device concomitantly with said repeating cycles. 
     
     
         17 . The device according to  claim 11 , wherein the pressure transition system comprises at least one sensor element adapted to register a physiological parameter of the body part, and transmit a data signal reflecting this parameter to the control unit. 
     
     
         18 . The device according to  claim 11 , wherein the pressure transition system comprises at least one sensor element adapted to register a parameter expressing an environmental condition in proximity to the body part, and transmit a data signal reflecting this parameter to the control unit. 
     
     
         19 . The device according to  claim 17 , wherein the treatment profile is adaptive in response to at least one manipulation signal. 
     
     
         20 . The device according to  claim 19 , wherein at least one of the at least one manipulation signal is based on at least one of said data signals. 
     
     
         21 - 30 . (canceled)