TACTILE ARRAY SENSOR

• US 20140088764A1
• Filed: 09/23/2013
• Published: 03/27/2014
• Est. Priority Date: 09/24/2012
• Status: Active Grant

• Current Assignee: Kshirsagar C.J. Naidu, Naidu, Prakash CRJ, Srinivasan A. Mandayam
• Original Assignee: Kshirsagar C.J. Naidu, Naidu, Prakash CRJ, Srinivasan A. Mandayam
• Inventors: Naidu, Prakash CRJ, Naidu, Kshirsagar CJ, Mandayam, Srinivasan A.
• Granted Patent: US 9,415,517 B2
• Time in Patent Office: Days
• US Class Current: 700/258
• CPC Class Codes: B25J 9/1694 characterised by use of sensors other than normal servo-feedback from position, speed or acceleration sensors, perception control, multi-sensor controlled systems, sensor fusion
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: G05B 2219/40625 Tactile sensor
• CPC Class Codes: G06F 1/00 Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00 architectures of general purpose stored program computers G06F15/76
• CPC Class Codes: G06F 2101/00 Indexing scheme relating to the type of digital function generated
• CPC Class Codes: G09G 2230/00 Details of flat display driving waveforms
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes

Abstract

A capacitance based tactile array sensor is disclosed that provides for close resolution of sensing pixels by using insulated conductors as electrodes, and allows for eliminating the need for a joint or connection interface near periphery of the sensor array. Optional aspects of the invention include provision for allowing use of stretchable conductors, reduction of the burden of number of connections at one layer of conductors in the sensor, providing for differential sensing resolutions at different areas of sensing, and modularity in configuration allowing replacement of a defective sensor pixel in the array. The tactile array sensor may be integrated with surface of a robotic hand'"'"'s finger, palm, or any other surface of a device that requires multi-point sensing of external contacts. The capacitance information is processed for useful display or control of systems based on the contact feedback.

Claims

1. A tactile array sensor comprising:

an array of sensor pixels formed by capacitance between overlapped layers of conductor electrodes laid in substantially orthogonal directions to each other;

a means to achieve close spatial resolution between adjacent conductor electrodes by use of said conductor electrodes in pre-insulated condition;

a means to achieve the said capacitance by insulation of conductor electrodes by dielectric material or by use of a separate dielectric material layer;

a means to hold the said sensor pixels in the said configuration;

functioning of sensor pixels by change in capacitance effected by sensing;

a means to enable sensing data acquisition from the sensor pixel array, its processing, and display or control of external devices based on the sensed information.

2. A tactile array sensor of claim 1 wherein the conductors are pre-insulated and thus continue to long lengths falling anywhere within a range between 1 cm to 100 cm on both sides of the tactile array eliminating the need for a joint or connection interface near periphery of the sensor array.

3. A tactile array sensor of claim 1 wherein the sensor data acquisition and processing unit is located away from the sensor array anywhere within a range between 1 cm to 100 cm, providing for remotely centralized unit connected to several sensor arrays.

4. A tactile array sensor of claim 1 wherein the conductors and their insulation are stretchable in one or two directions orthogonal to each other.

17. A method of use of a tactile array sensor of claim 1 comprising the steps:

(a) the tactile array sensor is attached to a robot body part such that the array of sensor pixels are exposed on the exterior surface of the robot body part

(b) the resolution of sensor pixels at different robot body parts is configured according to the needs of the respective body parts

(c) feedback from interaction of sensor pixels with environment around the robot conveys information to the robot or other control system

5. A tactile array sensor comprising:

an array of sensor pixels formed by capacitance between overlapped layers of conductor electrodes;

one layer of conductor electrodes laid in substantially radial configuration connected to a common center;

another layer of conductor electrodes laid in substantially circular and concentric configuration with the ends of the electrodes coming out radially in a common direction;

a means to achieve the said capacitance by insulation of conductor electrodes by dielectric material or by use of a separate dielectric material layer between the layers of conductor electrodes;

a means to hold the said sensor pixels in the said configuration;

functioning of sensor pixels by change in capacitance effected by sensing;

a means to enable data acquisition from the sensor pixel array, its processing, and display or control of external devices based on the sensed information.

6. A tactile array sensor of claim 5 wherein close spatial resolution between adjacent conductor electrodes in the second layer is achieved by use of said conductor electrodes in pre-insulated condition.

7. A tactile array sensor of claim 5 wherein reduction of the burden of number of connections at one layer of conductors in the sensor is achieved by radial conductor electrodes electrically connected to a common terminal at one end at the center of the sensor array.

8. A tactile array sensor of claim 5 wherein reduction of the overall computation burden of the sensor is achieved by having a broader resolution of sensor array at peripheral region while maintaining a closer resolution of sensing array at central region of the sensor.

18. A method of use of a tactile array sensor of claim 5 comprising the steps:

(a) the tactile array sensor is attached to a robot body part such that the array of sensor pixels are exposed on the exterior surface of the robot body part

(b) the resolution of sensor pixels at different robot body parts is configured according to the needs of the respective body parts

(c) feedback from interaction of sensor pixels with environment around the robot conveys information to the robot or other control system

9. A tactile array sensor comprising:

an array of sensor pixels formed by capacitance between overlapped layers of conductor electrodes;

one layer of conductor electrodes provided by a common ground electrode laid in substantially spiral configuration with an end coming out radially after the spiral;

another layer of conductor electrode pads arranged over the spiral ground electrode and connected to conductors laid in substantially spiral configuration with the ends of the conductors coming out radially in a common direction after the spiral;

a means to achieve the said capacitance by use of a dielectric material layer between the said layers of conductor electrodes;

a means to hold the said sensor pixels in the said configuration;

functioning of sensor pixels by change in capacitance effected by sensing;

a means to enable data acquisition from the sensor pixel array, its processing, and display or control of external devices based on the sensed information.

10. A tactile array sensor of claim 9 wherein close spatial laying of adjacent conductors in the second layer is achieved by use of the conductors in pre-insulated condition.

11. A tactile array sensor of claim 9 wherein reduction of the burden of number of connections at one layer of conductors in the sensor is achieved by common spiral ground conductor electrode electrically connected to a common terminal at one end at the periphery of the sensor array.

12. A tactile array sensor of claim 9 wherein reduction of the overall computation burden of the sensor is achieved by providing for a broader resolution of sensor array at one region while maintaining a closer resolution of sensing array at another region of the sensor.

19. A method of use of a tactile array sensor of claim 9 comprising the steps:

(a) the tactile array sensor is attached to a robot body part such that the array of sensor pixels are exposed on the exterior surface of the robot body part

(b) the resolution of sensor pixels at different robot body parts is configured according to the needs of the respective body parts

(c) feedback from interaction of sensor pixels with environment around the robot conveys information to the robot or other control system

13. A tactile array sensor comprising:

an array of sensor pixels formed by capacitance between overlapped layers of conductor electrodes;

one layer of conductor electrodes provided by a common ground electrode laid as a conductive surface with perforations;

another layer of conductor electrode pads arranged over the common ground electrode and connected to insulated conductors passing through the said perforations in a direction perpendicular to the surface of the tactile array sensor pixels;

a means to achieve the said capacitance by use of a dielectric material layer between the said layers of conductor electrodes;

a means to hold the said sensor pixels in the said configuration;

functioning of sensor pixels by change in capacitance effected by sensing;

a means to enable data acquisition from the sensor pixel array, its processing, and display or control of external devices based on the sensed information.

14. A tactile array sensor of claim 13 wherein sensing pads are assembled modularly by use of separate dielectric material washers providing for repair or replacement of individual sensor pixels.

15. A tactile array sensor of claim 13 wherein reduction of the burden of number of connections at one layer of conductors in the sensor is achieved by common ground conductor electrode electrically connected to a common terminal.

16. A tactile array sensor of claim 13 wherein reduction of the overall computation burden of the sensor is achieved by providing for a broader resolution of sensor array at one region while maintaining a closer resolution of sensing array at another region of the sensor.

20. A method of use of a tactile array sensor of claim 13 comprising the steps:

(a) the tactile array sensor is attached to a robot body part such that the array of sensor pixels are exposed on the exterior surface of the robot body part

(b) the resolution of sensor pixels at different robot body parts is configured according to the needs of the respective body parts

(c) feedback from interaction of sensor pixels with environment around the robot conveys information to the robot or other control system