Digital clay apparatus and method

• US 7,047,143 B2
• Filed: 07/13/2004
• Issued: 05/16/2006
• Est. Priority Date: 06/08/2001
• Status: Expired due to Fees

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Rossignac, Jaroslaw R., Allen, Mark, Glezer, Ari, Book, Wayne J., Ebert-Uphoff, Imme, Rosen, David W.
• Primary Examiner(s): Bui, Bryan
• Application Number:
  US10/889,916
• Publication Number:
  US 20040249582A1
• Time in Patent Office: 672 Days
• Field of Search: 702/11, 702/45, 702/155, 702/159, 356/375, 264/401
• US Class Current: 702/45
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user

Abstract

A system and method for controlling the surface and/or volume of a digital clay device is provided. One embodiment, among others, is a method comprising the following steps: determining a desired position of a skeleton structure portion residing in the digital clay device, determining a volumetric change of fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the skeleton structure portion, opening a valve so that the fluid flows through the valve thereby causing the determined volumetric change of the fluid, and adjusting a position of the skeleton structure portion corresponding to the desired position of the skeleton structure portion, the position adjustment caused by a force generated by the fluid cell on the skeleton structure portion when the volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

Claims

1. A method for controlling shape of a digital clay device, the method comprising:

determining a desired position of a skeleton structure portion residing in the digital clay device;

determining a volumetric change of a fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the skeleton structure portion;

opening a valve so that the fluid flows through the valve thereby causing the determined volumetric change of the fluid residing in the fluid cell; and

adjusting a position of the skeleton structure portion corresponding to the desired position of the skeleton structure portion, the position adjustment caused by a force generated by the fluid cell on the skeleton structure portion when volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

2. The method of claim 1, wherein opening the valve further comprises opening a hysteric valve.

3. The method of claim 1, wherein opening the valve further comprises opening an active valve.

4. The method of claim 1, wherein opening the valve further comprises opening a passive valve.

5. The method of claim 1, further comprising:

sensing flow of the fluid through the valve;

determining a measured volumetric change in the fluid from the sensed flow;

comparing the measured volumetric change to the determined volumetric change; and

closing the valve so that the fluid flow through the valve stops when the measured volumetric change substantially equals the determined volumetric change.

6. The method of claim 5, wherein sensing flow further comprises sensing a flow rate of the fluid through the valve.

7. The method of claim 5, wherein sensing flow further comprises sensing a pressure difference across the valve, and wherein determining the measured volumetric change further comprises calculating a flow rate of the fluid through the valve based upon the sensed pressure difference.

8. The method of claim 1, further comprising:

determining a plurality of volumetric changes of fluid residing in a plurality of fluid cells such that the sum of the determined plurality of volumetric changes corresponds to the determined desired position of the skeleton structure portion;

opening a corresponding plurality of valves so that fluid flows through the valve thereby causing the determined volumetric change of the fluid residing in the corresponding fluid cells;

sensing flow of fluid through each one of the plurality of valves;

determining a plurality of measured volumetric changes in the fluid from the sensed flows;

comparing each one of the plurality of measured volumetric changes to a corresponding one of the determined volumetric changes; and

closing the plurality of valves when the corresponding one of the measured volumetric changes substantially equals the corresponding determined volumetric change.

9. The method of claim 1, wherein the opening further comprises opening the valve so that the fluid flows through the valve thereby causing fluid to flow into the fluid cell in response to a pressure differential in a reservoir.

10. The method of claim 1, wherein the opening further comprises opening the valve so that the fluid flows through the valve thereby causing fluid to flow out of the fluid cell into a reservoir.

11. A method for controlling shape of a digital clay device, the method comprising:

determining a desired position of a skeleton structure portion residing in the digital clay device;

determining a volumetric change of a fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the skeleton structure portion;

changing volume of the fluid in the fluid cell thereby causing the determined volumetric change of the fluid residing in the fluid cell; and

adjusting a position of the skeleton structure portion corresponding to the desired position of the skeleton structure portion, the position adjustment caused by a force generated by the fluid cell on the skeleton structure portion when the volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

12. A method for sensing shape of a digital clay device, the method comprising:

determining an initial position of a skeleton structure portion residing in the digital clay device;

sensing a pressure change in a fluid cell, the pressure change corresponding to an external force applied to an exterior portion of the digital clay device;

opening a valve in response to the sensed pressure change such that fluid residing in the fluid cell exits the fluid cell;

sensing flow of the fluid through the valve;

closing the valve when the sensed pressure change is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cell, such that flow of the fluid through the valve stops;

determining a volumetric change in the fluid from the sensed flow after the valve is closed; and

determining a change in the position of the skeleton structure portion based upon the determined volumetric change.

13. The method of claim 12, wherein opening the valve further comprises opening a hysteric valve.

14. The method of claim 12, wherein opening the valve further comprises opening an active valve.

15. The method of claim 12, wherein opening the valve further comprises opening a passive valve.

16. The method of claim 12, wherein sensing pressure change further comprises sensing a rate of the pressure change.

17. The method of claim 16, wherein determining the change in the position of the skeleton structure portion is based upon the sensed rate of the pressure change.

18. The method of claim 12, further comprising:

determining a plurality of initial positions for each one of a plurality of skeleton structure portions residing in the digital clay device;

sensing a pressure change in a plurality of fluid cells, the pressure change corresponding to the external force applied to the exterior portion of the digital clay device;

opening a plurality of valves in corresponding ones of the plurality of fluid cells in response to the sensed pressure change such that fluid residing in the fluid cells exits the fluid cells;

sensing flow of the fluid through each one of the corresponding valves;

closing each one of the corresponding valves when the sensed pressure change in each one of the corresponding fluid cells is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cells;

determining volumetric change in the fluid from the sensed flow in each one of the corresponding valves after the valves are closed; and

determining change in the position of the skeleton structure portions based upon the determined volumetric changes.

19. A method for sensing shape of a digital clay device, the method comprising:

determining an initial position of a skeleton structure portion residing in the digital clay device;

sensing a pressure change in a fluid cell, the pressure change corresponding to an external force applied to an exterior portion of the digital clay device;

changing a volume of fluid residing in the fluid cell;

ending the volume change of the fluid when the sensed pressure change corresponds to at least a predefined value, the pressure change resulting from the volume change of the fluid in the fluid cell;

determining a volumetric change in the fluid from the sensed flow after ending the fluid removal; and

determining a change in the position of the skeleton structure portion based upon the determined volumetric change.

20. A system which controls a surface of a digital clay device, comprising:

a processor system;

a plurality of modules, each one of the plurality of modules further comprising;

at least one fluid cell, the fluid cell configured to hold a fluid;

at lease one valve, the valve controlled by the processor system; and

at least one sensor coupled to the valve, the sensor configured to sense flow of the fluid through the valve such that a volumetric change of the fluid residing in the fluid cell is determinable by the processor system; and

a covering having a plurality of surface portions, the covering being flexible and forming the surface of the digital clay device, each one of the surface portions coupled to selected ones of the plurality of modules such that a position of each one of the plurality of surface portions is controllable and determinable, the position of each one of the plurality of surface portions corresponding to an amount of the fluid residing in the corresponding fluid cell.

21. The system of claim 20, wherein the valve further comprises a hysteric valve.

22. The system of claim 20, wherein the valve further comprises an active valve.

23. The system of claim 20, wherein the valve further comprises a passive valve.

24. The system of claim 20, wherein each one of the modules further comprises a skeleton structure portion configured to kinematically constrain movement of the fluid cell in a predetermined direction.

25. The system of claim 20, wherein each one of the modules further comprises a backplate portion where the valve and the sensor reside.

26. The system of claim 20, wherein at least one of the modules comprises a single valve and a single sensor, the single valve configured to open in a first position such that the fluid flows into the fluid cell, and further configured to open in a second position such that the fluid flows out of the fluid cell.

27. The system of claim 20, further comprising a high pressure reservoir, the high pressure reservoir having a pressure greater than a fluid cell pressure of the fluid cell such that when a corresponding valve coupled between the fluid cell and the high pressure reservoir is opened, the fluid flows from the high pressure reservoir into the fluid cell.

28. The system of claim 20, further comprising a low pressure reservoir, the low pressure reservoir having a pressure less than a fluid cell pressure of the fluid cell such that when a corresponding valve coupled between the fluid cell and the low pressure reservoir is opened, fluid flows from the fluid cell into the low pressure reservoir.

29. A system for sensing shape of a digital clay device, comprising:

means for determining a desired position of a skeleton structure portion residing in the digital clay device;

means for determining a volumetric change of a fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the skeleton structure portion;

means for changing the volume of fluid in the fluid cell thereby causing the determined volumetric change of the fluid residing in the fluid cell; and

means for adjusting a position of the skeleton structure portion corresponding to the desired position of the skeleton structure portion, the position adjustment caused by a force generated by the fluid cell on the skeleton structure portion when the volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

30. The system of claim 29, further comprising:

means for sensing flow of the fluid;

means for determining a measured volumetric change in the fluid from the sensed flow; and

means for comparing the measured volumetric change to the determined volumetric change.

31. The system of claim 30, wherein the means for sensing flow further comprises means for sensing a pressure difference across a valve, and wherein the means for determining the measured volumetric change further comprises means for calculating a flow rate of the fluid through the valve based upon the sensed pressure difference.

32. A computer readable medium having a program for sensing shape of a digital clay device, the program comprising logic configured to perform:

determining a desired position of a skeleton structure portion residing in the digital clay device;

determining a volumetric change of a fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the skeleton structure portion;

communicating a first control signal to a valve such that the valve opens so that the fluid flows through the valve thereby causing the determined volumetric change of the fluid residing in the fluid cell; and

communicating a second control signal to the valve such that the valve closes when position of the skeleton structure portion adjusts the desired position of the skeleton structure portion, the position adjustment caused by a force generated by the fluid cell on the skeleton structure portion when the volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

33. A system which senses shape of a digital clay device, comprising:

means for determining an initial position of a skeleton structure portion residing in the digital clay device;

means for sensing a pressure change in a fluid cell, the pressure change corresponding to an external force applied to an exterior portion of the digital clay device;

means for adjusting volume of a fluid in the fluid cell in response to the sensed pressure change such that fluid residing in the fluid cell exits the fluid cell;

means for sensing flow of the fluid from the fluid cell;

means for ending flow of the fluid through the fluid cell when the sensed pressure change is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cell;

means for determining a volumetric change in the fluid after ending the flow of fluid; and

means for determining a change in the position of the skeleton structure portion based upon the determined volumetric change of the fluid.

34. The system of claim 33, further comprising means for returning the skeleton structure portion to a predetermined position such that the initial position of the skeleton structure portion is based upon the predetermined position.

35. The system of claim 33, further comprising means for retrieving information corresponding to a previous position of the skeleton structure portion such that the initial position of the skeleton structure portion is based upon the previous position.

36. A computer readable medium having a program for sensing shape of a digital clay device, the program comprising logic configured to perform:

determining an initial position of a skeleton structure portion residing in the digital clay device;

sensing a pressure change in a plurality of fluid cells, the pressure change corresponding to an external force applied to an exterior portion of the digital clay device;

opening at least one valve in response to the sensed pressure change such that fluid residing in the fluid cell exits the fluid cell;

sensing flow of the fluid through the valve;

closing the valve when the sensed pressure change is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cell, such that flow of the fluid through the valve stops;

determining a volumetric change in the fluid from the sensed flow after the valve is closed; and

determining a change in the position of the skeleton structure portion based upon the determined volumetric change.

37. A method for controlling shape of a surface using a digital clay device, the method comprising:

determining a desired position of at least one surface portion;

determining a volumetric change of a fluid residing in a fluid cell, the determined volumetric change corresponding to the determined desired position of the surface portion;

changing volume of the fluid in the fluid cell, thereby causing the determined volumetric change of the fluid residing in the fluid cell; and

adjusting a position of the surface portion corresponding to the desired position of the surface portion, the position adjustment caused by a force generated by the fluid cell when the volume of the fluid cell changes in response to the determined volumetric change of the fluid residing in the fluid cell.

38. The method of claim 37, further comprising:

sensing flow of the fluid;

determining a measured volumetric change in the fluid from the sensed flow;

comparing the measured volumetric change to the determined volumetric change; and

ending the flow of the fluid.

39. The method of claim 38, wherein sensing flow further comprises sensing a pressure difference across a valve, and wherein determining the measured volumetric change further comprises calculating a flow rate of the fluid through the valve based upon the sensed pressure difference.

40. The method of claim 37, further comprising:

determining a plurality of volumetric changes of fluid residing in a plurality of fluid cells such that the sum of the determined plurality of volumetric changes corresponds to the determined desired position of the surface portion;

changing volume of the fluid in the plurality of fluid cells thereby causing the determined volumetric change of the fluid residing in the corresponding fluid cells;

sensing flow of fluid of each one of the plurality of fluid cells;

determining a plurality of measured volumetric changes in the fluid in the plurality of fluid cells from the sensed flows;

comparing each one of the plurality of measured volumetric changes to a corresponding one of the determined volumetric changes; and

ending the flow of the fluid when the corresponding ones of the measured volumetric changes substantially equals the corresponding determined volumetric change.

41. The method of claim 37, further comprising:

opening a valve to a first position so that the fluid flows into the fluid cell when the determined volumetric change increases an amount of fluid residing in the fluid cell; and

opening the valve to a second position so that the fluid flows out of the fluid cell when the determined volumetric change decreases the amount of fluid residing in the fluid cell.

42. A method for sensing shape of a surface using a digital clay device, the method comprising:

determining an initial position of a surface portion;

sensing a pressure change in a fluid cell, the pressure change corresponding to an external force applied to the surface portion;

changing volume of the fluid in the fluid cell;

sensing flow of the fluid removed from the fluid cell;

ending the fluid flow when the sensed pressure change is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cell;

determining a volumetric change in the fluid from the sensed flow; and

determining a change in the position of the surface portion based upon the determined volumetric change.

43. The method of claim 42, further comprising returning the surface portion to a predetermined position such that determining the initial position of the surface portion is based upon the predetermined position.

44. The method of claim 42, further comprising retrieving information corresponding to a previous position of the surface portion such that determining the initial position of the surface portion is based upon the previous position.

45. The method of claim 42, further comprising:

determining a plurality of initial positions for each one of a plurality of surface portions;

sensing a pressure change in a plurality of fluid cells, the pressure change corresponding to the external force applied to the surface portions;

changing volume of the fluid in the fluid cells;

sensing flow of the fluid through each one of the fluid cells;

ending fluid flow when the sensed pressure change in each one of the corresponding fluid cells is reduced to at least a predefined value, the reduced pressure change resulting from the exit of fluid from the fluid cells;

determining a volumetric change in the fluid from the sensed flows; and

determining a change in the position of the surface portions based upon the determined volumetric changes.