RECOATER OPERATION ADJUSTMENTS BASED ON LAYER STRUCTURES

1 . A system comprising:

a recoater; and

a controller to:

identify a structure of a surface of a layer of build material formed on a build platform;

determine whether the identified structure of the surface includes a portion that has a property that is outside of a predefined property level;

based on a determination that the portion has a property that is outside of the predefined property level, determine an adjustment to be applied to an operation of the recoater to achieve an intended structure of the layer and/or an intended structure of a subsequent layer; and

apply the determined adjustment on the operation of the recoater.

2 . The system of claim 1 , wherein the controller is further to:

access a stereoscopic image of the surface of the layer; and

identify the structure of the surface from the accessed stereoscopic image.

3 . The system of claim 1 , wherein the property comprises a height of the portion with respect to other portions of the layer, a density of the portion, and/or a uniformity of a density of the portion with respect to other portions of the layer.

4 . The system of claim 1 , wherein the controller is to:

identify the structure of the surface of the layer prior to and/or following application of a selective joining operation on the build material in the layer.

5 . The system of claim 1 , wherein the controller is further to:

determine the adjustment to be applied to the operation of the recoater to include:

an additional scan of the recoater on the layer to further pack down the portion of the layer;

a modification to an operation of the recoater during formation of a subsequent layer;

a modification to an attribute of the recoater during the additional scan and/or during formation of a subsequent layer; and/or

a movement of the build platform with respect to the recoater.

6 . The system of claim 1 , wherein the controller is further to:

control the recoater to move across the build platform to form a layer of build material on the build platform; and

apply the determined adjustment through control of the operation of the recoater on the layer and/or the subsequent layer based on the determined adjustment.

7 . The system of claim 1 , further comprising:

fabrication components; and

wherein the controller is further to:

control the fabrication components to selectively join the build material in the layer;

identify the structure of the surface following the selective joining of the build material;

determine whether the identified structure of the surface following the selective joining of the build material includes the portion having the property that is outside of the predefined property; and

based on a determination that the portion of the identified structure of the surface following the selective joining include the portion having the property that is outside of the predefined property, determine the adjustment to be applied.

8 . The system of claim 1 , wherein the recoater is movable vertically with respect to the build platform and is also rotatable, and wherein the adjustment on the operation of the recoater comprises an adjustment to a vertical position of the recoater with respect to the build platform as the recoater is scanned across the build platform, a timing and/or speed at which the recoater is rotated as the recoater is scanned across the build platform, and/or temperatures at multiple locations of the recoater during scanning of the recoater across the build platform.

9 . A three-dimensional (3D) printing system comprising:

a recoater to form a layer of build material;

a stereoscopic imaging system to capture a stereoscopic image of the layer;

a controller; and

a memory on which is stored machine-readable instructions that when executed by the controller, cause the controller to:

determine, from the captured stereoscopic image, whether a portion of the layer has a property that is outside of a predefined property level;

determine, based on the portion of the layer having the property that is outside of the predefined property level, an adjustment to be applied to an operation of the recoater to achieve an intended structure of the layer and/or an intended structure of a subsequent layer to be formed above the layer; and

control the recoater to operate with the determined adjustment.

10 . The 3D printing system of claim 9 , further comprising:

fabrication components to selectively bind the build material in the layer; and

wherein the instructions are further to cause the controller to:

cause the stereoscopic imaging system to capture the stereoscopic image of the layer prior to the fabrication selectively binding the build material in the layer; and

wherein the captured stereoscopic image comprises the stereoscopic image of the layer captured prior to the fabrication selectively binding the build material in the layer.

11 . The 3D printing system of claim 9 , further comprising:

fabrication components to selectively bind the build material in the layer; and

wherein the instructions are further to cause the controller to:

cause the stereoscopic imaging system to capture the stereoscopic image of the layer following the fabrication components selectively binding of the build material in the layer; and

wherein the captured stereoscopic image comprises the stereoscopic image of the layer captured following the fabrication components selectively binding the build material in the layer.

12 . The 3D printing system of claim 9 , wherein the instructions are further to cause the controller to:

determine the adjustment to be applied to the operation of the recoater to include:

an additional scan of the recoater on the layer to further pack down the portion of the layer;

a modification to an operation of the recoater during formation of a subsequent layer;

a modification to an attribute of the recoater during the additional scan and/or during formation of a subsequent layer; and/or

a movement of the build platform with respect to the recoater.

13 . A method comprising:

identifying, by a controller and from an image of a surface of a build material layer, characteristics of the surface of the build material layer;

determining, by the controller, whether the identified characteristics identify a portion of the surface that has a property that is outside of a predefined property level;

based on a determination that the identified characteristics identify a portion having a property that is outside of the predefined property level, determining, by the controller, an adjustment to be applied to an operation of a recoater to achieve an intended characteristic of the build material layer and/or an intended characteristic of a subsequent build material layer; and

applying, by the controller, the determined adjustment on the operation of the recoater on the build material layer and/or a subsequent build material layer.

14 . The method of claim 13 , further comprising:

controlling the recoater to form the build material layer;

controlling a stereoscopic imaging system to capture stereoscopic images of the build material layer formed through operation of the recoater; and

identifying the characteristics of the surface of the build material layer from the captured stereoscopic images.

15 . The method of claim 13 , wherein determining the adjustment comprises determining the adjustment to be applied to the operation of the recoater to include:

an additional scan of the recoater on the layer to further pack down the portion of the layer;

a modification to an operation of the recoater during formation of a subsequent layer;

a modification to an attribute of the recoater during the additional scan and/or during formation of a subsequent layer; and/or

a movement of the build platform with respect to the recoater.