Sensor

• US 9,182,845 B2
• Filed: 03/24/2010
• Issued: 11/10/2015
• Est. Priority Date: 03/25/2009
• Status: Active Grant

• Current Assignee: Peratech Holdco Limited.
• Original Assignee: Peratech Holdco Limited.
• Inventors: Lussey, David, Graham, Mark Andrew
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): Ketema, Benyam
• Application Number:
  US13/259,471
• Publication Number:
  US 20120120009A1
• Time in Patent Office: 2,057 Days
• Field of Search: 345/173, 338/47
• US Class Current: 1/1
• CPC Class Codes: G06F 3/04146 using pressure sensitive conductive elements delivering a boolean signal and located between crossing sensing lines, e.g. located between X and Y sensing line layers

Abstract

A sensor for, and a method of, generating electrical signals indicating a positional property and an extent property of a mechanical interaction within a sensing zone. The sensor comprises a plurality of conductive layers. At least one conductive layer is a pressure-sensitive conductive layer comprising a quantum tunnelling conductance (qtc) material. Contact between conductive layers is allowed during the absence of a mechanical interaction within said sensing zone. The sensor may be configured to provide a three-terminal sensing functionality or a four-terminal sensing functionality. The sensing zone may be substantially two-dimensional or substantially three-dimensional. The sensor may be substantially flexible or substantially rigid.

Claims

1. A sensor for generating electrical signals indicating a positional property and an extent property of a mechanical interaction within a sensing zone, said sensor comprising a plurality of conductive layers, the plurality of conductive layers being placed on first and second sheets:

said first sheet carrying a first conductive layer having a first conductive area;

a first electrical terminal and a second electrical terminal in electrical connection with said first conductive area;

said first conductive area being configured to enable an electrical potential gradient to be established between said first electrical terminal and said second electrical terminal in a first direction extending across said first conductive layer;

said second sheet carrying a second conductive layer having a second conductive area;

a third electrical terminal in electrical connection with said second conductive area;

said sensor being configured such that an electrical path is established between said first conductive area and said second conductive area during a mechanical interaction within said sensing zone; and

at least one of said first sheet and said second sheet comprises a pressure-sensitive conductive layer comprising a quantum tunnelling conductance (qtc) material;

said sensor being configured such that direct electrical contact between said first and second conductive layers is permitted during the absence of a mechanical interaction within said sensing zone.

2. The sensor of claim 1, wherein said third electrical terminal is a sheet terminal.

3. The sensor of claim 1, wherein said second conductive area has a fourth electrical terminal connected thereto and is configured to allow an electrical potential gradient to be established between said third electrical terminal and said fourth electrical terminal, in a second direction that is substantially perpendicular to said first direction.

4. The sensor of claim 3, wherein

said first conductive layer presents a plurality of conductive rows, each row electrically insulated from the others, each row having a first electrical terminal and a second electrical terminal in electrical connection therewith and configured to allow an electrical potential gradient to be established between said first electrical terminal and said second electrical terminal, in a first direction, and

said second conductive layer presents a plurality of conductive columns, each column electrically insulated from the others, each column having a third electrical terminal and a fourth electrical terminal in electrical connection therewith and configured to allow an electrical potential gradient to be established between said third electrical terminal and said fourth electrical terminal, in a second direction that is substantially perpendicular to said first direction.

5. A method of generating electrical signals indicating a positional property and an extent property of a mechanical interaction within a sensing zone of a sensor, comprising the steps of:

receiving the sensor of claim 3,

establishing an electric potential gradient across said first conductive layer, between said first electrical terminal and said second electrical terminal, in said first direction,

receiving a first voltage from one of said third electrical terminal and said fourth electrical terminal of said second conductive layer, to produce a first positional value,

processing said first positional value to produce a first positional value of a mechanical interaction,

establishing an electric potential gradient across said second conductive layer, between said third electrical terminal and said fourth electrical terminal, in said second direction,

receiving a second voltage from one of said first electrical terminal and said second electrical terminal of said first conductive layer, to produce a second positional value,

processing said second positional value to produce a second positional value of a mechanical interaction,

establishing an electric potential from one of said first electrical terminal and said second electrical terminal of said first conductive layer, to produce a first current,

measuring said first current from one of said third electrical terminal and said second electrical terminal of said second conductive layer, to produce a first current value,

establishing an electric potential from the other of said first electrical terminal and said second electrical terminal of said first conductive layer, to produce a second current,

measuring said second current from the other of said third electrical terminal and said fourth electrical terminal of said second conductive layer, to produce a second current value, and

processing said second current value in combination with said first current value to produce an extent property of a mechanical interaction.

6. The sensor of claim 1, wherein a first pressure-sensitive conductive layer comprising a quantum tunnelling conductance (qtc) material provides said first conductive layer,

a second pressure-sensitive conductive layer comprising a quantum tunnelling conductance (qtc) material provides said second conductive layer, and

said sensor comprises said first conductive layer and said second conductive layer only.

7. The sensor of claim 1, wherein a pressure-sensitive conductive layer provides a third conductive layer that is disposed between said first conductive layer and said second conductive layer.

8. The sensor of claim 7, wherein a second pressure-sensitive conductive layer comprising a quantum tunnelling conductance (qtc) material provides a fourth conductive layer, and said fourth conductive layer and said second conductive layer are configured as a separate sheet to said first sheet.

9. The sensor of claim 1, wherein said extent property is one of:

magnitude of applied force, magnitude of applied pressure, area of mechanical interaction.

10. The sensor of claim 1, wherein said sensing zone is non-planar, said sensor being constructed of a plurality of molded parts assembled together.

11. The sensor of claim 1, wherein at least one conductive layer comprises textile fibres.

12. A method of generating electrical signals indicating a positional property and an extent property of a mechanical interaction within a sensing zone of a sensor, comprising the steps of:

receiving the sensor of claim 1,

establishing an electric potential gradient across said first conductive layer, between said first electrical terminal and said second electrical terminal, in said first direction,

receiving a first voltage from said third electrical terminal, to produce a first positional value,

processing said first positional value to produce a first positional property of a mechanical interaction,

establishing an electric potential from one of said first electrical terminal and said second electrical terminal of said first conductive layer, to produce a first current,

measuring said first current from said third electrical terminal of said second conductive layer, to produce a first current value,

establishing an electric potential from the other of said first electrical terminal and said second electrical terminal of said first conductive layer, to produce a second current,

measuring said second current from said third electrical terminal of said second conductive layer, to produce a second current value, and

processing said second current value in combination with said first current value to produce an extent property of a mechanical interaction.