Digital foam

• US 7,886,621 B2
• Filed: 03/06/2009
• Issued: 02/15/2011
• Est. Priority Date: 03/06/2009
• Status: Active Grant

• Current Assignee: University of South Australia (University of Adelaide)
• Original Assignee: University of South Australia (University of Adelaide)
• Inventors: Piekarski, Wayne, Smith, Ross Travers, Thomas, Bruce Hunter
• Primary Examiner(s): NOORI, MAX H
• Application Number:
  US12/381,147
• Publication Number:
  US 20100225340A1
• Time in Patent Office: 711 Days
• Field of Search: 737/77, 73862381-862391
• US Class Current: 73/862.381
• CPC Class Codes: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors

Abstract

A displacement sensor element and a haptic sensor arrangement using two or more displacement sensor elements are provided. The arrangements can be used for real-time capture of the shape of haptic deformation of the sensor arrangement. Although examples described in detail herein are primarily directed to tactile applications, the sensor can be used in the machine, robotic and medical fields where a sensor of this type can usefully be applied where only machine or computer controlled robotic elements are interacting, particularly if the machines or robotic elements are being used in human like applications but other force measurement applications are possible.

Claims

1. A displacement sensor array comprising:

two or more conductive elastomeric members, each of which is elastomeric along at least one axis of the elastomeric member and has at least one electrical characteristic that changes when the elastomeric member is compressed along the at least one axis by a force, wherein the conductive elastomeric members have a known spatial configuration relative to each other and are not in physical contact with each other;

an electrically conductive first elastomeric terminal in electrical contact with all of the elastomeric members;

two or more second conductive terminals, each in electrical contact with a corresponding one of the elastomeric members, wherein each said second terminal is located on an opposite side of the corresponding elastomeric member than the first elastomeric terminal, along the at least one axis of the corresponding elastomeric member; and

wherein the known spatial configuration of the elastomeric members combined with the change in the at least one electrical characteristic of a respective conductive elastomeric member affected by a force applied to the first conductive terminal, determines the spatial location of the force relative to one or more of the conductive elastomeric members and relative to at least one of the second conductive terminals.

2. The sensor array of claim 1 wherein the first elastomeric terminal comprises a conductive elastomeric fabric.

3. The sensor array of claim 1 wherein the elastomeric members comprise a material having gaseous voids.

4. The sensor array of claim 1 wherein the electrical characteristics of the elastomeric members comprise one or more members of the group consisting of:

voltage, current, resistance, dielectric constant, and capacitance.

5. The sensor array of claim 1 further comprising a non-conductive elastomeric material disposed between at least two of the conductive elastomeric members.

6. The sensor array of claim 1 further comprising a substrate on which two or more of the second conductive terminals are disposed.

7. A displacement sensor comprising:

a substrate;

at least two spaced apart and electrically conductive elastomeric members, wherein each of the elastomeric members is elastomeric along at least one axis and has at least one electrical characteristic that changes when the member is compressed along the least one axis, and wherein each of the elastomeric members is at a known spatial location with respect to the substrate;

an elastomeric electrically conductive tactile force transference terminal (TFTT) in electrical contact with each of the elastomeric members such that in response to a tactile actuation of the TFTT, an electrical characteristic of at least one of the elastomeric members changes;

at least two electrically conductive terminals, each terminal in electrical contact with a corresponding one of the elastomeric members; and

a processor for measuring the at least one electrical characteristic of each of the elastomeric members between each electrically conductive terminal and the TFTT, and determining the spatial location of a force applied to the TFTT from the measured electrical characteristics and the known locations of the elastomeric members.

8. The displacement sensor of claim 7 further comprising a non-conductive elastomeric material arranged to substantially fill the volume between the spaced apart conductive elastomeric members and electrically isolate the conductive elastomeric members from each other.

9. The displacement sensor of claim 8 wherein the non-conductive elastomeric material has substantially the same elastomeric response characteristics as the conductive elastomeric members.

10. The displacement sensor of claim 7 wherein the electrical characteristics of the elastomeric members comprise one or more members of the group consisting of:

voltage, current, resistance, dielectric constant, and capacitance.

11. The displacement sensor of claim 7 wherein the electrical characteristics of the elastomeric members are processed by the processor so as to substantially map a surface topography of the TFTT with respect to the substrate.

12. The displacement sensor of claim 7 wherein the TFTT comprises an electrically conductive fabric.

13. The displacement sensor of claim 7 wherein the elastomeric members comprise a material having gaseous voids.

14. A method of providing user input to a computer, the method comprising:

providing a displacement sensor according to claim 7;

providing an orientation sensing capability for the displacement sensor;

altering a force applied to the displacement sensor to create an input to the computer to select a menu input mode for the computer;

altering an orientation of the displacement sensor to create an input to the computer to effect a change in menu selection; and

altering a force applied to the displacement sensor to create an input to the computer to make a menu selection.

15. The method of claim 14 further comprising applying a force to one or more locations on the displacement sensor to create an input to the computer to provide interaction with a virtual model of an object.