System and method for determining a build plan based upon an analyzed build plate geometric signature

1. A three-dimensional (3D) printing system for manufacturing a three-dimensional (3D) article comprising:

a resin vessel for containing a volume of photocurable resin having a resin upper surface;

an imaging system configured to define a build plane;

a build plate having a build plate upper surface that is inclined at an oblique angle with respect to a lateral axis and the oblique angle is proportional to a height H which exists between a lowest point and a highest point over a build area over which the 3D article is to be fabricated over the build plate upper surface;

a build plate positioner;

a sensor configured to generate a signal indicative of a fluid-related vertical position of one or more of the resin upper surface and a component of a volume compensator (VC);

a controller configured to:

operate the build plate positioner to vertically translate the build plate upper surface from a state of non-immersion to a state of immersion and/or from a state of immersion to a state of non-immersion;

concurrent with operating the build plate positioner, receiving the signal from the sensor, the signal indicative of a fluid level vertical deflection that increases with the oblique angle and the height H;

analyze the signal to determine the height H; and

form a plurality of base layers having a cumulative thickness at least equal to the height H before beginning to form layers of the 3D article.

2. The three-dimensional (3D) printing system of claim 1 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point at a first vertical position of the build plate at which a low point of the build plate upper surface is positioned at the resin upper surface, formation of the plurality of base layers begins at the first vertical position of the build plate.

3. The three-dimensional (3D) printing system of claim 1 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point that defines the height H and a number N of the plurality of base layers to fabricate before fabricating the 3D article.

4. The three-dimensional (3D) printing system of claim 3 wherein the number N of base layers fabricated before fabrication of the 3D article is equal to the height H divided by a thickness t of one base layer plus a predetermined number of additional layers.

5. The three-dimensional (3D) printing system of claim 1 wherein the analyzing the signal defines a curve, the curve is a first or second derivative of a function of fluid-related vertical position versus a build plate position, the curve is analyzed to determine a lowest or highest vertical position of the build plate upper surface.

6. The three-dimensional (3D) printing system of claim 1 wherein the analyzing the signal defines a curve and a determination of whether a previously fabricated article is present upon the build plate upper surface.

7. A method of manufacturing a three-dimensional (3D) article comprising:

providing a three dimensional printing system including:

a resin vessel for containing a volume of photocurable resin having a resin upper surface;

an imaging system configured to define a build plane;

a build plate having a build plate upper surface that is inclined at an oblique angle with respect to a lateral axis and the oblique angle is proportional to a height H which exists between a lowest point and a highest point over a build area over which the 3D article is to be fabricated over the build plate upper surface;

a build plate positioner;

a sensor configured to generate a signal indicative of a fluid-related vertical position of one or more of the resin upper surface and a component of a volume compensator (VC); and a controller and;

operating the controller to:

operate the build plate positioner to vertically translate the build plate upper surface from a state of non-immersion to a state of immersion and/or from a state of immersion to a state of non-immersion;

concurrent with operating the build plate positioner, receiving the signal from the sensor, the signal indicative of a fluid level vertical deflection that increases with the oblique angle and the height H;

analyze the signal to determine the height H a build plate geometric signature; and

form a plurality of base layers having a cumulative thickness at least equal to the height H before beginning to form layers of the 3D article.

8. The method of claim 7 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point at a first vertical position of the build plate at which a low point of the build plate upper surface is positioned at the resin upper surface, formation of the plurality of base layers begins at the first vertical position of the build plate.

9. The method of claim 7 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point that defines the height H and a number N of the plurality of base layers to fabricate before fabricating the 3D article.

10. The method of claim 9 wherein the number N of base layers fabricated before fabrication of the 3D article is equal to the height H divided by a thickness t of one base layer plus a predetermined number of additional layers.

11. The method of claim 7 wherein the analyzing the signal defines a curve, the curve is a first or second derivative of a function of fluid-related vertical position versus a build plate position, the curve is analyzed to determine a lowest or highest vertical position of the build plate upper surface.

12. The method of claim 7 wherein the analyzing the signal defines a curve and a determination of whether a previously fabricated article is present upon the build plate upper surface.

13. A non-transient storage media storing software instructions, when executed by a processor, the software instructions control portions of a three-dimensional printing system, the three dimensional printing system including a resin vessel for containing a volume of photocurable resin having a resin upper surface, an imaging system configured to define a build plane, a build plate having a build plate upper surface that is inclined at an oblique angle with respect to a lateral axis and the oblique angle is proportional to a height H which exists between a lowest point and a highest point over a build area over which the 3D article is to be fabricated over the build plate upper surface, a build plate positioner, and a sensor configured to generate a signal indicative of a fluid-related vertical position of one or more of the resin upper surface and a component of a volume compensator (VC), when executed by the processor the software instructions perform at least the following steps:

operate the build plate positioner to vertically translate the build plate upper surface from a state of non-immersion to a state of immersion and/or from a state of immersion to a state of non-immersion;

concurrent with operating the build plate positioner, receiving the signal from the sensor, the signal indicative of a fluid level vertical deflection that increases with the oblique angle and the height H;

analyze the signal to determine the height H; and

form a plurality of base layers having a cumulative thickness at least equal to the height H before beginning to form layers of the 3D article.

14. The non-transient storage media of claim 13 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point at a first vertical position of the build plate at which a low point of the build plate upper surface is positioned at the resin upper surface, formation of the plurality of base layers begins at the first vertical position of the build plate.

15. The non-transient storage media of claim 13 wherein the analyzing the signal defines a curve, the curve having a change in slope or inflection point that defines the height H and a number N of the plurality of base layers to fabricate before fabricating the 3D article.

16. The non-transient storage media of claim 15 wherein the number N of base layers fabricated before fabrication of the 3D article is equal to the height H divided by a thickness t of one base layer plus a predetermined number of additional layers.

17. The non-transient storage media of claim 13 wherein the analyzing the signal defines a curve, the curve is a first or second derivative of a function of fluid-related vertical position versus a build plate position, the curve is analyzed to determine a lowest or highest vertical position of the build plate upper surface.

18. The non-transient storage media of claim 13 wherein the analyzing the signal defines a curve and a determination of whether a previously fabricated article is present upon the build plate upper surface.