SYSTEM FOR SENSING AND DISPLAYING SOFTNESS AND FORCE

• US 20110107842A1
• Filed: 04/20/2009
• Published: 05/12/2011
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: Concordia University
• Original Assignee: Concordia University
• Inventors: Sokhanvar, Saeed, Dargahi, Javad
• Granted Patent: US 8,596,111 B2
• Time in Patent Office: Days
• US Class Current: 73/780
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: G01N 2203/0623 using piezoelectric gauges
• CPC Class Codes: G01N 3/40 Investigating hardness or rebound hardness

Abstract

A sensing element for sensing the softness of an object by abutting the sensing element against the object and biasing the sensing element toward the object with a biasing force. The sensing element includes a deformable section, the deformable section being deformable between an undeformed configuration and a deformed configuration, the deformed configuration being achievable when the deformable section is abutted against and biased toward the object; a deformation sensor operatively coupled to the deformable section for sensing a deformation of the deformable section between the deformed and undeformed configurations; and a force sensor operatively coupled to the deformable section for sensing the biasing force exerted onto the deformable section by the object when the deformable section is biased toward the object with the biasing force.

Claims

1. A sensing element for sensing the softness of an object by abutting said sensing element against said object and biasing said sensing element toward said object with a biasing force, said sensing element comprising:

a deformable section, said deformable section being deformable between an undeformed configuration and a deformed configuration, said deformed configuration being achievable when said deformable section is abutted against and biased toward said object;

a deformation sensor operatively coupled to said deformable section for sensing a deformation of said deformable section between said deformed and undeformed configurations; and

a force sensor operatively coupled to said deformable section for sensing said biasing force exerted onto said deformable section by said object when said deformable section is biased toward said object with said biasing force.

2. A sensing element as defined in claim 1, further comprising

a base;

and

a spacing element extending substantially away from said base;

said deformable section being supported by said spacing element in a substantially spaced apart relationship relatively to said base.

3. A sensing element as defined in claim 2, wherein said deformable section and said base are substantially parallel to each other.

4. A sensing element as defined in claim 2, wherein said deformation sensor includes a piezoelectric material operatively coupled to said deformable section for producing an electrical signal upon a deformation of said deformable section between said deformed and undeformed configurations.

5. A sensing element as defined in claim 2, wherein said deformation sensor includes a capacitor operatively coupled to said deformable section and to said base for producing an electrical signal upon a deformation of said deformable section between said deformed and undeformed configurations.

6. A sensing element as defined in claim 5, wherein said capacitor includes a first metal plate secured to said base and a second metal plate secured to said deformable section, said first and second metal plates being substantially in register with each other.

7. A sensing element as defined in claim 6, wherein said first and second metal plates are located between said deformable section and said base.

8. A sensing element as defined in claim 2, wherein said force sensor is mechanically coupled to said spacing element for sensing a force exerted on said spacing element when said deformable section is abutted against and biased toward said object

9. A sensing element as defined in claim 8, wherein said force sensor includes a piezoelectric material operatively coupled to said spacing element for producing an electrical signal upon a force being exerted on said spacing element.

10. A sensing element as defined in claim 9, wherein said piezoelectric material is provided between said base and said spacing element.

11. A sensing element as defined in claim 1, further comprising

a base;

and

a pair of spacing elements extending substantially away from said base;

said deformable section extending between said spacing elements and being supported by said spacing elements in a substantially spaced apart relationship relatively to said base.

12. A sensing element as defined in claim 1, further comprising

a base, said base defining a recess extending thereinto, said base including a base material delimiting said recess;

said deformable section including a deformable material substantially filling said recess, said deformable material being substantially more deformable than said base material when when said deformable section and said base material are simultaneously abutted against and biased toward said object.

13. A sensing element as defined in claim 12, wherein said force sensor includes a piezoelectric material mechanically coupled to said base and to said deformable section for sensing forces exerted onto said deformable material and said base when said deformable material and said base material are simultaneously abutted against and biased toward said object.

14. A sensing element as defined in claim 12, wherein said base and said deformable section together define an abutment surface for abutting against said object, said sensing element comprising a sheet of piezoelectric material mechanically coupled to both said deformable material and said base material substantially opposed to said abutment surface.

15. A sensing element as defined in claim 14, wherein:

said deformation sensor including a deformation sensor electrode electrically coupled to said sheet of piezoelectric material for receiving electrical signals from said sheet of piezoelectric material when a force is exerted onto said deformable material;

said force sensor including a force sensor electrode electrically coupled to said sheet of piezoelectric material for receiving electrical signals from said sheet of piezoelectric material when a force is exerted onto said base material;

said force sensor and position sensor electrodes being electrically insulated from each other.

16. A softness sensor, said softness sensor including a plurality of sensing elements as defined in claim 1, said plurality of sensing elements being distributed over a predetermined sensing surface.

17. A softness sensor as defined in claim 16, wherein said predetermined sensing surface is substantially planar.