Video based 3D tactile reconstruction input device having a deformable membrane

• US 5,459,329 A
• Filed: 09/14/1994
• Issued: 10/17/1995
• Est. Priority Date: 09/14/1994
• Status: Expired due to Term

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Sinclair, Michael J.
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): LE, QUE TAN
• Application Number:
  US08/306,160
• Time in Patent Office: 398 Days
• Field of Search: 250/561, 250/227.24, 250/341.8, 250/358.1, 250/330-334, 356/376, 356/377, 382/25, 382/26, 128/654, 128/656, 378/207
• US Class Current: 250/559.29
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G09B 25/06 for surveying; for geography, e.g. relief models globes G09B27/00; maps G09B29/00

Abstract

A tactile image mapper has a vessel with a deformable membrane on one side and a clear face plate on the other side. The vessel is filled with an optically dense material, such as ink, and a pressure regulator varies and measures the pressure of the optically dense material to cause the deformable membrane to assume the shape of an object to be tactually sensed. A ring illuminator shines light through the clear face plate to the back side of the deformable membrane and a video camera captures the reflections off of the back side of the deformable membrane. A microcomputer captures a frame from the video signal and interprets areas with high intensities in the frame as protrusions on the surface of the object and areas with low intensities in the frame as low areas on the object. Based upon the interpretations at each point within the frame of the video signal, the tactile image mapper reconstructs a high resolution synthesized three dimensional topographical image of the object.

Claims

1. An imaging system for producing a high resolution topographic representation of an object, comprising:

deformable means for deforming to at least a portion of a shape of an object in contact therewith, said deformable means having a light reflecting surface;

means for detecting reflections from said reflecting surface and for converting the detected reflections into data signals;

light modifying means between said reflecting surface and said detecting means for varying the intensity of the reflections in accordance with a deformation of said deforming means; and

means for processing said data signals to produce said high resolution image of said object.

2. The system as set forth in claim 1, wherein said means for detecting said reflections comprises a video camera.

3. The system as set forth in claim 1, further comprising means for illuminating said light reflecting surface.

4. The system as set forth in claim 3, wherein said illuminating means comprises a ring illuminator for uniformly illuminating said reflecting surface of said deformable means.

5. The system as set forth in claim 1, further comprising means for regulating the resistance to deformation of said deformable means.

6. The system as set forth in claim 1, wherein said data signals comprise video signals.

7. The system as set forth in claim 1, wherein said light modifying means comprises a light attenuating material for attenuating said reflections.

8. The system as set forth in claim 7, wherein said light attenuating material comprises ink.

9. A tactile image mapper, comprising:

a vessel for holding a light attenuating material and having a deformable membrane for deforming to a shape of an object, said membrane forming one side of said vessel and a clear transparent plate forming a second side of said vessel opposite said one side;

an illuminator for illuminating an inside reflective surface of said deformable membrane;

a camera for detecting reflections from said inside surface of said deformable membrane and for generating a video signal; and

a processor for capturing a single frame of said video signal and for reconstructing a high resolution image of said object.

10. The tactile image mapper as set forth in claim 9, further comprising a pressure regulator and transducer for varying and measuring a pressure of said light attenuating material to a preset pressure.

11. The tactile image mapper as set forth in claim 10, wherein a plurality of high resolution images of said object are obtained at a respective plurality of different preset pressures.

12. The tactile image mapper as set forth in claim 9, wherein said illuminator comprises a ring illuminator for uniformly illuminating said inside surface of said deformable membrane.

13. The tactile image mapper as set forth in claim 9, wherein said light attenuating material comprises ink.

14. A method for producing a high resolution image of an object, comprising the steps of:

placing one side of a deformable membrane in contact with said object and deforming said membrane to a shape of said object;

illuminating a reflective side of said membrane, said reflective side being opposite said one side;

modifying light reflected from said reflective side in accordance with a deformation of said deformable membrane;

detecting reflections from said reflective side of said membrane and converting said reflections into data signals; and

processing said data signals to produce said high resolution image of said object.

15. The method as set forth in claim 14, wherein said step of deforming comprises the step of varying the resistance to deformation of the membrane.

16. The method as set forth in claim 15, wherein the step of varying the resistance of the membrane comprises setting the stiffness of the membrane to any one of a plurality of pre-determined levels.

17. The method as set forth in claim 14, wherein said step of modifying light reflected from said reflective side comprises the step of passing said reflected light through a light attenuating material.