Stryker Corporation

Hill-rom Services, Inc.

Ontario Limited

Hill-fom Services, Inc.

Verg, Inc.

1625986 Ontario Limited

Geoffrey Locke Taylor

James R Stolpmann

Kerry Jean Mensching

James H Price

Karl Norman Caldwell

James Milton Cherry Thomas

Marla Repik

Nick Bries

William Lawrence Chapin

Grant D Derksen

An apparatus and a method of monitoring fat burning in a subject non-invasively by measuring electric conductivity or resistance on the skin.

Fat burning monitoring

A flexible force or pressure sensing mat includes a first sheet of electrically conductive first paths, a second sheet of electrically conductive second paths, and a sensing layer positioned between the first and second sheets. The first and second conductive paths are oriented transversely to each other, and the locations of their intersections define individual sensing areas or sensors. The sensing layer is made from materials that have first and second electrical characteristics&#x2014;such as capacitance and resistance&#x2014;that vary in response to physical forces exerted thereon. A controller repetitively measures the multiple electrical characteristics of each sensor in order to produce a near real time pressure distribution map of the forces sensed by the mat. The mat can be used on a patient support surface&#x2014;such as a bed, cot, stretcher, recliner, operating table, etc.&#x2014;to monitor and help reduce the likelihood of a patient developing pressure ulcers.

Force detecting mat with multiple sensor types

A pressure sensing sheet includes at least first, second, and third layers wherein the first and third layers each have conductive paths defined therein that are separated by nonconductive spacers. The orientation of the conductive paths of the first layer are transverse to the orientation of the conductive paths of the third layer. The second layer is made of material that has an electrical characteristic that changes with applied pressure, such as, but not limited to, piezoresistive or piezoelectric material. The first and/or third layers are made from multi-material sheets wherein a first type of material will repel conductive particles when subjected to an autocatalytic coating process, while the second type of material will bond with the conductive particles during the autocatalytic coating process. The use of different materials in the first and/or third layers facilitates the manufacturing of the conductive paths and nonconductive spacers.

Pressure sensing mat

Flexible force/pressure sensors for producing electrical output signals proportional to forces or pressures exerted on the sensor include a thin, elastically deformable foam pad laminated between a pair of electrically conducive fabric sheets. A piezocapacitive embodiment of the sensor utilizes an elastically deformable perforated open-cell polyurethane foam pad preferably saturated with glycerin to increase the capacitance of the sensor. The piezocapacitive sensor section is preferably stacked onto a piezoresistive section having a second open-cell foam pad containing piezoresistive carbon particles to form a hybrid piezocapacitive/piezoresistive sensor. A third, 'leaky dielectric' embodiment of a sensor includes a single open-cell foam pad which contains both a dielectric liquid and conductive particles. A low frequency such as d.c. to a few hertz is applied to a sensor to determine piezoresistive response of the sensor to forces or pressures and a higher frequency such as 30 KHz is applied to determine piezocapactive response.

Flexible piezocapacitive and piezoresistive force and pressure sensors

An adaptive cushion for reducing pressure on body parts of a person positioned on a chair or bed includes an overlay cushion having a plurality of individual air bladder cells, each having thereon a force sensor. The cushion includes a controller for inflating and deflating individual air bladder cells to air pressures that tend to reduce the interface pressures sensed by the force sensors. A pressure reduction method includes varying the inflation pressure in a first air bladder cell while measuring the sum of the interface pressures exerted on all or a plurality of the air bladder cells, re-pressurizing the first cell to that air pressure for which a minimum total interface pressure was obtained, repeating this process for the remaining air bladder cells.

Adaptive cushion method and apparatus for minimizing force concentrations on a human body

A force sensing array includes multiple layers of material that are arranged to define an elastically stretchable sensing sheet. The sensing sheet may be placed underneath a patient to detect interface forces or pressures between the patient and the support structure that the patient is positioned on. The force sensing array includes a plurality of force sensors. The force sensors are defined where a row conductor and a column conductor approach each other on opposite sides of a force sensing material, such as a piezoresistive material. In order to reduce electrical cross talk between the plurality of sensors, a semiconductive material is included adjacent the force sensing material to create a PN junction with the force sensing material. This PN junction acts as a diode, limiting current flow to essentially one direction, which, in turn, reduces cross talk between the multiple sensors.

Force sensing sheet

Force or pressure transducer arrays have elastically stretchable electrically conductive polymer threads disposed in parallel rows and columns that contact at intersections thereof a piezoresistive material which has an electrical resistivity which varies inversely with pressure or force exerted thereon to form a matrix array of force or pressure sensor elements. The threads are fixed to a single one or pair of flexible elastically stretchable substrate sheets made of thin sheets of an insulating polymer such as PVC, or for greater elasticity and conformability to irregularly-shaped objects such as human body parts, an elastically stretchable fabric such as LYCRA or SPANDEX. Elastic stretchability of the sensor arrays is optionally enhanced by disposing either or both row and column conductive threads in sinuously curved, serpentine paths rather than straight lines.

Elastically stretchable fabric force sensor arrays and methods of making

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.

A patient support surface comprises a cover defining an interior region, a modifiable support layer situated in the interior region and having at least one air bladder, and a sensor layer situated in the interior region and having at least one sensor configured to detect a physiological parameter of a patient atop the patient support surface.

Patient support surface with vital signs sensors

Patient support surface with physiological sensors

A support surface includes a cover defining an interior region, a mattress core located in the interior region, and a force sensor located in the interior region.

Force optimization surface apparatus and method

A force optimization apparatus is provided including a patient support surface and an interface pressure sensor.

A remote wound assessment method and apparatus includes forming an oblique image of a wound and a target plate containing a rectangle and placed near the wound. Using a novel method of determining vanishing points where photographic images of parallel lines on the target object intersect, coordinate transformations are calculated which map the oblique image of the rectangle into a normal image thereof. Using the same coordinate transformations, an oblique image of a wound adjacent to the target plate is mapped into a normal view thereof, allowing precise measurement of wound features. By forming two separate images of a wound and target plate at two different oblique inclinations, three dimensional features of a wound may be measured.

Growing community of inventors

Winnipeg, Canada

Geoffrey Locke Taylor