Dielectric geometry for capacitive-based tactile sensor
A dielectric for a capacitive-based tactile sensor of the type having a pair of spaced apart conductive plates with the dielectric conductively therebetween, includes a body of a non-rigid dielectric polymeric material. The body is shaped into a microstructure defined by a plurality of members adapted to extend from one of the conductive plates to the other. Some of the members includes a first feature shaped to have a first end surface and a second end surface. Second features are integral with the first feature and project from the second end surface. A cross-section area of each of the second features is substantially smaller than a cross-section area of the first feature at the second end surface. A height of the first feature in a distance between the conductive plates is substantially greater than a height of the second features. A capacitive-based tactile sensor with the dielectric is also provided.
1. A dielectric for a capacitive-based tactile sensor of the type having a pair of spaced apart conductive plates with the dielectric conductively therebetween, the dielectric comprising:
a body of a non-rigid dielectric polymeric material, the body being shaped into a microstructure defined by a plurality of members adapted to extend from one of the conductive plates to the other, at least some of the members comprising:
a first feature shaped to have a first end surface and a second end surface;
at least two second features integral with the first feature and projecting from the second end surface;
a cross-section area of each of the second features being substantially smaller than a cross-section area of the first feature at the second end surface; and
a height of the first feature in a distance between the conductive plates being substantially greater than a height of the second features.
2. The dielectric according to claim 1 , wherein the first feature is generally shaped as a truncated cone.
3. The dielectric according to claim 1 , wherein the second features are generally shaped as cones or truncated cones.
4. The dielectric according to claim 1 , wherein the first feature is generally shaped as a cylinder.
5. The dielectric according to claim 1 , wherein the second features are generally shaped as cylinders.
6. The dielectric according to claim 1 , wherein the non-rigid dielectric polymeric material is silicone embedded with at least one of microparticles and nanoparticles.
7. The dielectric according to claim 6 , wherein the silicone is embedded with at least a ferroelectric ceramic for increased relative permittivity of silicone.
8. The dielectric according to claim 1 , wherein the body is a monolithic molded piece.
9. The dielectric according to claim 1 , wherein a ratio of height of the first feature to the second feature ranges between 3:1 to 30:1.
10. The dielectric according to claim 1 , wherein a ratio of cross-section areas of the first feature to the second feature ranges between 3:1 to 40:1.
11. A capacitive-based tactile sensor comprising:
at least a pair of spaced apart conductive plates and adapted to be wired to a controller;
at least one body of a non-rigid dielectric polymeric material conductively received between the conductive plates, the body being shaped into a microstructure defined by a plurality of members extending from one of the conductive plates to the other, at least some of the members comprising:
a first feature shaped to have a first end surface and a second end surface;
at least two second features integral with the first feature and projecting from the second end surface;
a cross-section area of each of the second features being substantially smaller than a cross-section area of the first feature at the second end surface; and
a height of the first feature in a distance between the conductive plates being substantially greater than a height of the second features.
12. The capacitive-based tactile sensor according to claim 11 , wherein the first feature is generally shaped as a truncated cone.
13. The capacitive-based tactile sensor according to claim 11 , wherein the second features are generally shaped as cones or truncated cones.
14. The capacitive-based tactile sensor according to claim 11 , wherein the first feature is generally shaped as a cylinder.
15. The capacitive-based tactile sensor according to claim 11 , wherein the second features are generally shaped as cylinders.
16. The capacitive-based tactile sensor according to claim 11 , wherein the non-rigid dielectric polymeric material is silicone embedded with at least one of microparticles and nanoparticles.
17. The capacitive-based tactile sensor according to claim 16 , wherein the silicone is embedded with at least a ferroelectric ceramic for increased relative permittivity of silicone.
18. The capacitive-based tactile sensor according to claim 11 , wherein the body is a monolithic molded piece.
19. The capacitive-based tactile sensor according to claim 11 , wherein a ratio of height of the first feature to the second feature ranges between 3:1 to 30:1.
20. The capacitive-based tactile sensor according to claim 11 , wherein a ratio of cross-section areas of the first feature to the second feature ranges between 3:1 to 40:1.