Sensor with a plurality of sensor elements arranged with respect to a substrate

• US 20050268699A1
• Filed: 07/11/2005
• Published: 12/08/2005
• Est. Priority Date: 12/30/2003
• Status: Active Grant

• Current Assignee: Tekscan, Inc.
• Original Assignee: Tekscan, Inc.
• Inventors: Papakostas, Thomas, Lowe, Mark, George, Christopher, Malacaria, Charles
• Granted Patent: US 7,258,026 B2
• Time in Patent Office: Days
• US Class Current: 73/46
• CPC Class Codes: G01L 1/20 by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids of piezo-resistive materials G01L1/18; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress

Abstract

A sensor for measuring a parameter applied to a surface is provided. The sensor includes at least one substrate layer, a plurality of individual sensor elements operatively arranged with respect to the substrate layer, and a conductive trace disposed on the substrate layer. The conductive trace is electrically coupled to an individual sensor element and wraps around at least a portion of the sensor element in a spiral-like manner. Further, by employing slits or cut-outs of material between sensor elements, a sensor element may move independent of an adjacent sensor element, thereby allowing the sensor to conform to an irregularly shaped surface or otherwise when subject to relatively large deflections. The sensor may be employed to detect force distribution of a seating surface, such as a seat cushion of a wheelchair.

Claims

1. A sensor, adapted to conform to the shape of a surface, comprising:

a substrate layer; and

a plurality of individual sensor elements, for measuring a desired parameter, the plurality of sensor elements defining a sensor plane, the sensor elements are arranged with respect to the substrate layer in a manner that allows each sensor element to move in a direction perpendicular to the sensor plane and substantially independent of an adjacent sensor element moving in a direction perpendicular to the sensor plane.

2. The sensor of claim 1, wherein the substrate layer is formed of a thin, flexible material and is constructed and arranged to allow a sensor element to move relative to another sensor element.

3. The sensor of claim 1, further comprising a plurality of slits formed in the substrate layer at locations suitable to allow a sensor element to move relative to another sensor element.

4. The sensor of claim 3, wherein each of the plurality of slits are formed along a nonlinear path.

5. The sensor of claim 1, wherein the plurality of sensor elements is arranged on a substrate layer, wherein the substrate layer comprises a plurality of cut-outs at locations suitable to allow a sensor element to move relative to another sensor element.

6. The sensor of claim 5, wherein at least one cut-out formed in the substrate layer is positioned between multiple sensor elements and is generally diamond or kite shaped.

7. The sensor of claim 1, wherein at least one sensor element comprises a pressure sensitive layer.

8. The sensor of claim 7, wherein the pressure sensitive layer comprises a conductive ink.

9. The sensor of claim 1, wherein the plurality of sensor elements is arranged on a substrate layer in an array of rows and columns.

10. The sensor of claim 1, wherein at least a plurality of sensor elements is configured to detect a force, in combination with an apparatus for the custom fitting of a wheelchair seat or seat cushion, wherein the apparatus comprises:

a platform to which the sensor is mounted; and

a controller communicating with the sensor, wherein the controller is adapted to receive data from the sensor and calculate a force at locations coincident with locations of individual sensor elements of the sensor upon the sensor being subjected to a force.

11. The sensor of claim 1, further comprising a first conductive trace, wherein the first conductive trace comprises a plurality of first conductive traces disposed on the substrate layer, wherein a first one of the conductive traces extends at least partially around one of the plurality of individual sensor elements in a first spiral-like pattern and in a first direction, and wherein a second one of the first conductive traces extends at least partially around another one of the plurality of individual sensor elements in a second spiral-like pattern and in a second direction, wherein the first and second directions are substantially opposite each other.

12. The sensor of claim 11, wherein:

the plurality of individual sensor elements comprises a first plurality of individual sensor elements arranged in a first row and a second plurality of individual sensor elements arranged in a second row,

the first one of the first conductive traces is electrically coupled to and extends in a counter-clockwise direction at least partially around a first one of the first plurality of individual sensor elements in the first row, then extends in a clockwise direction at least partially around the first one of the first plurality of individual sensor elements in the first row, then is electrically coupled to and extends in a counter-clockwise direction at least partially around a second one of the first plurality of individual sensor elements in the first row, then extends in a clockwise direction at least partially around the second one of the first plurality of individual sensor elements in the first row; and

the second of the first conductive traces is electrically coupled to and extends in a clockwise direction at least partially around a first one of the second plurality of individual sensor elements in the second row, then extends in a counter-clockwise direction at least partially around the first one of the second plurality of individual sensor elements in the second row, then is electrically coupled to and extends in a clockwise direction at least partially around a second one of the second plurality of individual sensor elements in the second row, then extends in a counter-clockwise direction at least partially around the second one of the second plurality of individual sensor elements in the second row.

13. A sensor, adapted to conform to the shape of a surface, comprising:

a substrate layer; and

a plurality of individual sensor elements, each adapted to measure a parameter from a range of parameters, the plurality of sensor elements defining a sensor plane, the sensor elements are arranged with respect to the substrate layer in a manner that allows each sensor element to move in a direction perpendicular to the sensor plane and substantially independent of an adjacent sensor element moving in a direction perpendicular to the sensor plane.