Adaptive cushion method and apparatus for minimizing force concentrations on a human body
First Claim
1. An adaptive cushion apparatus for reducing the magnitude of reaction force concentrations exerted on parts of a human body in response to contact with a supporting object, said apparatus comprising:
- a. a cushion for placement between a supporting object and a human body, said cushion having at least first and second hermetically sealable air bladder cells each made of a flexible, air impervious material, said first and second cells being hermetically isolated from each other,b. at least first and second force sensitive sensors associated with said first and second air bladder cells, respectively, each of said sensors having an electrical characteristic which varies in a predetermined way with a force exerted on a said air bladder cell by a said body,c. a pressurization device for pressurizing a hollow interior space of each of said air bladder cells to an individually controllable pressure,d. at least one pressure transducer operatively coupleable to each of said air bladder cells to thereby measure gas pressure within said hollow interior spaces of said air bladder cells, ande. a control apparatus having a force sensor interface port for receiving signals from said force sensors, a pressure transducer port for receiving signals from said pressure transducer, and an output port for providing control signals to said pressurization device to thereby pressurize air within said air bladder cells to individually controllable values, said control apparatus adapted to pressurize air within said first air bladder cell based upon sums of readings from said first and second force sensitive sensors.
4 Assignments
0 Petitions
Accused Products
Abstract
An adaptive cushion apparatus for minimizing force concentrations on body parts of a person seated or lying on a chair or bed includes an overlay cushion having a plurality of individual air bladder cells, each having thereon a stretchable piezoresistive force sensor of novel design and construction. The apparatus includes an electro-pneumatic control system for inflating and deflating individual air bladder cells to pressures measured by a pressure transducer which tend to minimize force concentrations sensed by the force sensors. A force minimization method according to the invention includes varying the inflation pressure in a first air bladder cell while measuring the sum of the forces exerted on all air bladder cells, repressurizing the first cell to that pressure for which a minimum total force was obtained, repeating the cyclical variation in pressure and re-inflation to a minimum force-obtaining pressure for each of the remaining air bladder cells, and repeating the sequence for all air bladder cells until the force variations are minimized below a predetermined threshold value.
201 Citations
36 Claims
-
1. An adaptive cushion apparatus for reducing the magnitude of reaction force concentrations exerted on parts of a human body in response to contact with a supporting object, said apparatus comprising:
-
a. a cushion for placement between a supporting object and a human body, said cushion having at least first and second hermetically sealable air bladder cells each made of a flexible, air impervious material, said first and second cells being hermetically isolated from each other, b. at least first and second force sensitive sensors associated with said first and second air bladder cells, respectively, each of said sensors having an electrical characteristic which varies in a predetermined way with a force exerted on a said air bladder cell by a said body, c. a pressurization device for pressurizing a hollow interior space of each of said air bladder cells to an individually controllable pressure, d. at least one pressure transducer operatively coupleable to each of said air bladder cells to thereby measure gas pressure within said hollow interior spaces of said air bladder cells, and e. a control apparatus having a force sensor interface port for receiving signals from said force sensors, a pressure transducer port for receiving signals from said pressure transducer, and an output port for providing control signals to said pressurization device to thereby pressurize air within said air bladder cells to individually controllable values, said control apparatus adapted to pressurize air within said first air bladder cell based upon sums of readings from said first and second force sensitive sensors. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29)
-
-
30. An adaptive cushion apparatus comprising:
-
a first air bladder; a second air bladder, said second air bladder being hermetically isolatable from said first air bladder; a pressure sensing sheet positioned above said first and second air bladders, said pressure sensing sheet adapted to detect interface pressures exerted between a patient supported on said adaptive cushion and said first and second air bladders; and a control system in communication with said pressure sensing sheet, said control system adapted to calculate an initial sum of interface pressures exerted on said first and second bladders and to thereafter monitor subsequent sums of interface pressures exerted on both said first and second bladders while an inflation level within said first bladder is changed through a range of values by said control system, said controller adapted to thereafter set the inflation level within said first air bladder to a value corresponding to a selected one of said subsequent sums, said selected one of said subsequent sums being less than said initial sum. - View Dependent Claims (31, 32, 33, 34, 35, 36)
-
Specification