Apparatus and method for monitoring contact pressure between body parts and contact surfaces

Apparatus adapted to monitor pressure at a plurality of locations along an exterior surface of a body part of a user to produce a force profile corresponding to a distribution of force caused by pressure of said body part against a contact surface, comprising:

• (a) a plurality of pressure sensors supported on at least one strip of flexible substrate material and organized in an array such that each of said sensors has a coordinate address within the array, said strip and said sensors adapted to be interposed between and in contact with both the exterior surface of said body part and said contact surface at selected locations at which pressure is to be monitored, each of said sensors operative in response to pressure to generate an analog force signal proportional to the pressure between the exterior of said body part and said contact surface at its respective location;
• (b) monitor means in communication with the array of said sensors for receiving the analog force signals produced by said sensors and for producing output signals having pressure data representative of the pressure sensed by said sensors, said monitor means including multiplexer circuitry adapted to select the force signal from a selected one of said sensors, an analog-to-digital converter operative to convert said analog force signals to digital force signals and a microprocessor operative to generate address signals whereby said multiplexer circuitry selects the force signal from an addressed sensor so that said converter produces a digital force signal corresponding to the addressed sensor, said monitor means operative to produce each of said output signals in response to the respective digital force signal from said converter;
• (c) computer processing means in communication with said monitor means for receiving and processing the output signals to produce the force profile defining the distribution of force corresponding to the magnitude and location of pressure exerted between the contact surface and the exterior surface of said body part, said computer processing means including command means for generating a read signal operative to cause said monitor means to generate said address signals to generate said output signals and to communicate a set of said output signals correlated to each of said sensors to define a read event;
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• (d) at least one switch means adapted to be positioned remotely of said computer processing means and in proximity to said body part, said switch means for producing a switch active signal in response to one of a plurality of events initiated by force caused by said body part acting on said switch means and indicative of specific pressure states on said body part, said monitor means operative after receipt of said read signal to initiate a read event in response to said switch active signal.

A method of monitoring pressure between a prosthesis and an exterior surface of a residual limb to produce a force profile corresponding to a distribution and magnitude of force caused by pressure of said residual limb against an interface portion of the prosthesis interfacing said prosthesis and said residual limb when said prosthesis contacts a support surface, comprising the steps of:

• (a) interposing a plurality of pressure sensors between and in contact with both the exterior surface of said residual limb and said interface portion of said prosthesis at selected locations, each of said sensors operative in response to compressive pressure between the exterior of said residual limb and said interface portion of said prosthesis at its respective location to generate a force signal proportional to the pressure therebetween;
• (b) monitoring the force signals to produce an output signal in response to each force signal having pressure data corresponding to the pressure sensed by the respective sensor wherein the step of monitoring said sensors is accomplished by executing a read event at a selected time so that an array of sensors is scanned to general said output signals;
• (c) disposing at least one switch on said prosthesis for producing a switch active signal when said switch is in an active state, whereby said step of executing a read event occurs in response to said switch active signal;
• (d) receiving said output signals and storing the pressure data correlated to the location of each respective sensor;
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• (e) displaying said pressure date as said force profile indicating the distribution of force corresponding to the pressure and location of pressure exerted between the interface portion of said prosthesis and the exterior surface of said residual limb.

Apparatus adapted to monitor pressure at a plurality of locations along an exterior surface of a residual limb of a user wearing a prosthesis, said apparatus for contemporaneously producing a force profile when said prosthesis contacts a support surface, said force profile corresponding to a distribution of force caused by pressure of said limb against a contact surface of said prosthesis, comprising:

• (a) a plurality of pressure sensors organized in an array such that said sensors may be interposed between the exterior surface of said residual limb and said contact surface at selected locations at which pressure is to be monitored, each of said sensors operative in response to pressure between the exterior surface of said residual limb and said contact surface at its respective location to generate a force signal proportional to the pressure therebetween;
• (b) monitor means in communication with the array of said sensors for receiving the force signal produced by each respective said sensor and for producing an output signal having pressure data corresponding to the pressure sensed by the respective said sensor;
• (c) processing means in communication with said monitor means for receiving and processing said output signals to produce the force profile corresponding to the magnitude and location of pressure exerted by the contact surface on the exterior surface of said residual limb, said processing means including common means for generating a read signal operative to cause said monitor means to generate said output signals and to communicate a set of said output signals correlated to each of said sensors to define a read event;
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• (d) a switch disposed on a portion of said prosthesis, said switch for producing a switch active signal in response to contact of said portion against the support surface which contact is caused by an event initiated by said residual limb exerting a force on said switch and indicative of a specific pressure state of said residual limb, said monitor means operative after receipt of said read signal to initiate a read event in response to said switch active signal.