Method and system for hierarchical multi-scale part design with the aid of a digital computer

Patent metadata

Field	Value
Publication number	US-11507054-B2
Application number	US-201816236949-A
Country	US
Kind code	B2
Filing date	Dec 31, 2018
Priority date	Dec 31, 2018
Publication date	Nov 22, 2022
Grant date	Nov 22, 2022

Abstract

The present disclosure is directed to a method and system for hierarchical multi-scale design with the aid of a digital computer. A hierarchical representation of a shape and material distribution is constructed which satisfies a top-level constraint at a top-level of representation. Properties for families of designs at each of the lower levels of representation that satisfy additional constraints link each of the lower levels of representation to at least a next higher level of the representation.

First claim

The invention claimed is:

1. A computer-implemented method comprising:
specifying at least one design criterion comprising at least one constraint;
constructing a hierarchical representation of families of designs that satisfy the at least one design criterion at every level of the hierarchical representation, each family comprising an equivalence class of shape and material distribution fields, the hierarchical representation comprising lower levels of representation that provide more details about the families of designs than higher levels of representation, the lower levels of representation further restricting the families of designs compared to the higher levels of representation;
synthesizing the families of designs at every level of the hierarchical representation that satisfy the specified criteria as well as additional constraints that link the levels of the hierarchical representation, wherein synthesizing the families of designs comprises invoking a forward solver to evaluate objective functions and constraint violations at each level of the representation;
determining a lowest level of representation of the hierarchical representation that produces a final design at a detail suitable for manufacturing; and
manufacturing a part according to the final design via a manufacturing instrument.

2. The method of claim 1 , wherein the design criteria further comprise at least one objective function that provides a figure of merit for designs that satisfy the at least one constraint and the additional constraints, the synthesizing the families of designs further comprising optimization with respect to the objective function.

3. The method of claim 1 , wherein the hierarchical representation comprises of surrogate properties of shape and material distributions for the families of designs, the surrogate properties providing sufficient information to evaluate the families of designs against the design criteria.

4. The method of claim 3 , wherein the surrogate properties comprise finite subsequences of a convergent sequence or a series of variables that represent a projection of the shape and material distributions at a given level onto a functional basis.

5. The method of claim 4 , wherein longer subsequences are decided at the lower levels of representation.

6. The method of claim 3 , wherein each level of the hierarchical representation comprises a spatial cellular decomposition wherein each cell at each level of the spatial cellular decomposition is assigned with one or more surrogate properties.

7. The method of claim 6 , wherein each cell at each level is decomposed into disjoint cells to obtain next cells at a next lower level.

8. The method of claim 6 , wherein each level of the hierarchical representation describes the shape and the material distributions at a size scale determined by a size of each cell.

9. The method of claim 6 , wherein the additional constraints link the properties of a cell at a given level to properties of the cells obtained from the decomposition.

10. The method of claim 9 , wherein the surrogate properties are integral properties of the shape and material distributions within each cell and the additional constraints that link them across the levels are of additivity of the integral properties.

11. The method of claim 3 , wherein final shape and material distributions are not determined until the surrogate properties are synthesized for all levels of representation.

12. A system comprising:
a processor coupled to memory, the memory storing instructions executable by the processor for performing:
synthesizing a hierarchical representation of surrogate properties of shape and material distributions of a family of designs by a spatial cellular decomposition with the surrogate properties assigned to each cell at each level of the hierarchical representation, each family comprising an equivalence class of shape and material distribution fields;
starting from a top level of the hierarchical representation, determining the surrogate properties at the top level that satisfy constraints specified at the top level based on an analysis performed at the top level;
for each level below the top level, performing a process comprising further decomposing each cell at a given level into disjoint child cells of a next level, decisions on the surrogate properties assigned to the disjoint child cells being made based on an analysis performed at the given level subject to additional constraints that enforce the properties at each cell at the given level to remain consistent with the surrogate properties decided at each cell at a previous level, wherein the analysis comprises invoking a forward solver to evaluate objective functions and constraint violations at the given level; and
determining a lowest level of representation of the hierarchical representation that produces a final design at a detail suitable for manufacturing; and
a manufacturing instrument that builds a part according to the final design.

13. The system of claim 12 , wherein the surrogate properties synthesized at each level declaratively represent a family or equivalence class of designs that possess the surrogate properties, and wherein the decisions at each level further restrict the class of designs into subclasses by redistributing the properties of a cell in the previous level.

14. The system of claim 12 , wherein the process terminates when the family or the equivalence class of designs is restricted enough at a bottom level of the representation to be interpreted as a class of interchangeable designs realized by at least one of given manufacturing processes and material microstructures.

15. The system of claim 14 , wherein the given manufacturing process or material microstructure is finalized after the synthesis of the surrogate properties is complete at all levels.

16. The system of claim 12 , wherein the processor further optimizes the surrogate properties at one or more of the levels according to one or more objective functions.

17. The system of claim 16 , wherein the optimization comprises enumerating solutions along Pareto fronts.

18. The system of claim 12 , wherein the decisions at each level are performed by iterations over one or more candidate families of designs represented by the surrogate properties at the given level.

19. The system of claim 18 , wherein the iterations are guided by sensitivities or gradients of at least one of the constraints or objective functions at the given level to changes in the surrogate properties.

20. A method comprising:
visualizing a hierarchical representation of surrogate properties of shape and material distributions of a family of designs by a spatial cellular decomposition with properties assigned to each cell at each level of the hierarchical representation, each family comprising an equivalence class of shape and material distribution fields, and wherein the surrogate properties are determined by invoking a forward solver to evaluate objective functions and constraint violations at each level;
displaying a color-coding of values of surrogate properties at specified levels of the representation;
determining a lowest level of representation of the hierarchical representation that produces a final design at a detail suitable for manufacturing; and
manufacturing a part according to the final design via a manufacturing instrument.

Assignees

• Palo Alto Res Ct Inc

Inventors

• Behandish Morad
• Mirzendehdel Amir
• Nelaturi Saigopal

Classifications

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• G06F2113/10

  Additive manufacturing, e.g. three-dimensional [3D] printing · CPC title

• G05B2219/49007

  Making, forming 3-D object, model, surface · CPC title

• G06F30/23

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title

• B33Y50/00

  Data acquisition or data processing for additive manufacturing · CPC title