Prosthetic system and method utilizing microprocessor-controlled electric vacuum pump

Abstract

A prosthetic system having a microprocessor-controlled socket evacuation device, and a method of retaining a prosthesis on the residual limb of an amputee using such an evacuation device are described herein. The evacuation device can include an electrically powered vacuum pump. The evacuation device can be operated in a manner that automatically adjusts the socket vacuum level to correspond to a determined activity level of a user. The microprocessor control can also limit operation of the evacuation device to certain determined portions of a user's gait cycle.

What is claimed is: 
     
         1 . A prosthetic system, comprising:
 a socket comprising an interior that receives a residual limb;   a vacuum passageway extending from the interior of socket;   an electrically powered vacuum pump in communication with the vacuum passageway;   at least one pressure sensor that monitors vacuum pressure within the socket;   a microprocessor in communication with the evacuation device and the at least one pressure sensor, the microprocessor programmed to automatically:
 evacuate the interior of the socket with the electrically powered vacuum pump to a vacuum level; 
 observe the vacuum pressure within the socket based on signals from the at least one pressure sensor; 
 determine an activity level of a user of the socket based upon the vacuum pressure that is observed; 
 determine a correlating vacuum level based upon the activity level; and 
 evacuate the interior of the socket with the electrically powered vacuum pump to the correlating vacuum level. 
   
     
     
         2 . The prosthetic system of  claim 1 , wherein the correlating vacuum level is greater than the vacuum level when the activity level is increased. 
     
     
         3 . The prosthetic system of  claim 1 , wherein the correlating vacuum level is less than the vacuum level when the activity level is decreased. 
     
     
         4 . The prosthetic system of  claim 1 , wherein the microprocessor is programmed to automatically observe fluctuation of the vacuum pressure within the socket based, wherein the fluctuation is the vacuum pressure within the socket as a function of time, and wherein the activity level is determined using the fluctuation of the vacuum pressure. 
     
     
         5 . The prosthetic system of  claim 4 , wherein the microprocessor is programmed to automatically track a gait cycle using the fluctuation of the vacuum pressure within the socket. 
     
     
         6 . The prosthetic system of  claim 1 , comprising a residual limb motion sensor integrated into the socket and in communication with the microprocessor. 
     
     
         7 . The prosthetic system of  claim 6 , wherein the microprocessor is programmed to automatically:
 detect motion of the residual limb using the residual limb motion sensor;   determine an appropriate vacuum level based upon the motion that is detected; and   construct a map of activity level and vacuum level using the appropriate vacuum level and the activity level.   
     
     
         8 . The prosthetic system of  claim 6 , wherein the microprocessor is programmed to automatically:
 detect motion of the residual limb using the residual limb motion sensor; and   adjust the correlating vacuum level based upon the motion of the residual limb.   
     
     
         9 . The prosthetic system of  claim 1 , wherein the microprocessor is programmed to automatically reference a map of activity level and vacuum level, wherein the correlating vacuum level is determined using the map of activity level and vacuum level. 
     
     
         10 . The prosthetic system of  claim 1 , comprising an additional sensor associated with the socket and in communication with the microprocessor, wherein the additional sensor comprises an accelerometer, a gyroscope, a force sensor, or a combination thereof, and wherein the microprocessor is programmed to automatically monitor movement using signals from the additional sensor. 
     
     
         11 . The prosthetic system of  claim 1 , wherein the microprocessor is programmed to automatically track an amount of pressure the residual limb is exposed to within the socket over a period of time. 
     
     
         12 . A method for controlling a vacuum pump, comprising:
 receiving a residual limb with an interior of a socket of a prosthetic device, wherein the prosthetic device comprises a vacuum passageway extending from the interior of socket, an electrically powered vacuum pump in communication with the vacuum passageway, and at least one pressure sensor that monitors vacuum pressure within the socket;   evacuating the interior of the socket with the electrically powered vacuum pump to a vacuum level;   observing, automatically with the microprocessor, the vacuum pressure within the socket based on signals from the at least one pressure sensor;   determining, automatically with the microprocessor, an activity level of a user of the socket based upon the vacuum pressure that is observed;   determining, automatically with the microprocessor, a correlating vacuum level based upon the activity level; and   evacuating the interior of the socket with the electrically powered vacuum pump to the correlating vacuum level.   
     
     
         13 . The method of  claim 12 , wherein the correlating vacuum level is greater than the vacuum level when the activity level is increased. 
     
     
         14 . The method of  claim 12 , wherein the correlating vacuum level is less than the vacuum level when the activity level is decreased. 
     
     
         15 . The method of  claim 12 , comprising observing, automatically with the microprocessor, fluctuation of the vacuum pressure within the socket based, wherein the fluctuation is the vacuum pressure within the socket as a function of time, and wherein the activity level is determined using the fluctuation of the vacuum pressure. 
     
     
         16 . The method of  claim 15 , comprising tracking, automatically with the microprocessor, a gait cycle using the fluctuation of the vacuum pressure within the socket. 
     
     
         17 . The method of  claim 12 , wherein the prosthetic device comprises a residual limb motion sensor integrated into the socket and in communication with the microprocessor. 
     
     
         18 . The method of  claim 17 , comprising:
 detecting motion of the residual limb using the residual limb motion sensor;   determining an appropriate vacuum level based upon the motion that is detected; and   constructing a map of activity level and vacuum level using the appropriate vacuum level and the activity level.   
     
     
         19 . The method of  claim 17 , comprising:
 detecting motion of the residual limb using the residual limb motion sensor; and   adjusting the correlating vacuum level based upon the motion of the residual limb.   
     
     
         20 . The method of  claim 12 , comprising referencing, automatically with the microprocessor, a map of activity level and vacuum level, wherein the correlating vacuum level is determined using the map of activity level and vacuum level. 
     
     
         21 . The method of  claim 12 , comprising monitoring movement using signals from an additional sensor associated with the socket, wherein the additional sensor comprises an accelerometer, a gyroscope, a force sensor, or a combination thereof. 
     
     
         22 . The method of  claim 12 , comprising tracking an amount of pressure the residual limb is exposed to within the socket over a period of time. 
     
     
         23 . A prosthetic system, comprising:
 a socket comprising an interior that receives a residual limb;   a vacuum passageway extending from the interior of socket;   an electrically powered vacuum pump in communication with the vacuum passageway;   a microprocessor in communication with the electrically powered vacuum pump, the microprocessor programmed to automatically:   evacuate the interior of the socket with the electrically powered vacuum pump to maintain a vacuum level;   monitor a duty cycle of the electrically powered vacuum pump;   compare the duty cycle of the electrically powered vacuum pump to a baseline duty cycle; and   provide a measure of air leaks based upon comparison of the duty cycle and the baseline duty cycle.