Multi-stage incremental sheet forming system and method

Abstract

To provide a system and a method for forming a structure which comprises a steep wall (for example, a wall with an angle of 60 degrees or greater) through incremental sheet forming.SOLUTION: A system comprises: a formation tool; and at least one control unit communicating with the formation tool. At least one control unit is configured to specify a convex closure (convex hull) of a target structure which is formed by the formation tool. The at least one control unit is configured to operate the formation tool according to a first tool path with respect to, an initial structure, for forming an intermediate structure comprising a shape based on the convex closure of the target structure. The at least one control unit is configured to operate the formation tool according to a second tool path, with respect to the intermediate structure, for forming one or more inward properties in the intermediate structure, for forming the target structure.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to multi-stage incremental sheet forming systems and methods. [Background technology]

[0002] Certain structures are formed via incremental sheet forming. In particular, incremental sheet forming provides a method for forming thin structures from metal. Forming tools typically include smooth, blunt, operable heads that are pressed or otherwise placed against the surface of sheet metal suspended in a clamp, fixture, or the like to provide a modified three-dimensional shape.

[0003] During an incremental sheet forming process, a forming tool (such as a forming stylus) traverses a tool path to incrementally deform a blank sheet of metal. It is common to generate the tool path from a stack of level sections of the shape of the part to be formed, known as a Z-level tool path.

[0004] The incremental sheet forming process is known to be sensitive to local wall inclination angles. In general, structures with steep wall angles greater than 60 degrees from the horizontal plane are typically not viable candidates for incremental sheet forming. Above 60 degrees, sheets of metal formed via incremental sheet forming processes typically thin to approximately half their original thickness. Attempts to form such structures via incremental sheet forming have been found to risk fracture of the steep walls of the material.

[0005] Overall, single-stage incremental sheet forming using Z-level tool paths often fails when applied to complex parts with features such as pockets or insets formed on steep walls (e.g., walls formed at angles of at least 60 degrees). Using the Z-level tool path approach, the steep walls thin excessively during the forming process, which can result in (or at least risk of) tearing of the sheet of material. Structures with walls at angles of 60 degrees or greater are typically not suitable for incremental sheet forming. Summary of the Invention

[0006] What is needed are systems and methods for forming structures with steep walls (e.g., walls with angles of 60 degrees or greater) via incremental sheet forming. Additionally, what is needed are incremental sheet forming systems and methods that are not vulnerable to damaging (e.g., breaking) the structural material at steep angles (e.g., 60 degrees or greater).

[0007] In light of these needs, certain embodiments of the present disclosure provide a multi-stage incremental sheet forming system including a forming tool and at least one control unit in communication with the forming tool. The at least one control unit is configured to identify a convex hull of a target structure to be formed by the forming tool. The at least one control unit is configured to operate the forming tool according to a first tool path relative to the initial structure to form an intermediate structure having a shape based on the convex hull of the target structure. The at least one control unit is configured to operate the forming tool according to a second tool path relative to the intermediate structure to form one or more inward features in the intermediate structure to form the target structure, where the second tool path is different from the first tool path.

[0008] In at least one embodiment, the at least one control unit includes a tool path generation control unit configured to determine at least one tool path, a tool path generation control unit configured to determine a convex hull of the target structure, and a forming control unit configured to operate the forming tool.

[0009] In at least one embodiment, the at least one control unit includes a tool path generation control unit configured to identify a convex hull of the target structure based on the smallest convex set that encompasses all points of the target structure.

[0010] In at least one embodiment, a structural database is in communication with the at least one control unit and stores target data including information regarding a geometric representation of the target structure, such as a size of the target structure, a shape of the target structure, one or more inward facing features of the target structure, and manufacturing data including tool geometry, tool size, and tool feed rate.

[0011] In at least one embodiment, the at least one control unit includes a tool path generation control unit that includes a convex hull identification module that analyzes target data related to the target structure and identifies a convex hull of the target structure based on the target data.

[0012] In at least one embodiment, the at least one control unit includes a tool path generation control unit including a convex hull tool path generation module that identifies a first tool path based on the identified convex hull. The forming control unit operates a forming tool according to the first tool path relative to the initial structure to form an intermediate structure having a shape based on the convex hull of the target structure. As one example, the first tool path is a Z-level tool path.

[0013] In at least one embodiment, the at least one control unit includes a tool path generation control unit including a target structure tool path generation module configured to operate and / or output instructions to operate a forming tool according to a second tool path relative to the intermediate structure to form one or more inward features in the intermediate structure to form the target structure. As one example, the second tool path is a lace tool path.

[0014] In at least one embodiment, the one or more inward features include one or more of at least one indentation, at least one cavity, at least one divot, at least one channel, at least one recess, at least one groove, at least one crease, at least one pocket, at least one inset, or at least one hole.

[0015] In at least one embodiment, the target structure includes at least one wall disposed at an angle of at least 60 degrees relative to a level plane, and in at least one embodiment, the intermediate structure lacks one or more inward-facing features.

[0016] Certain embodiments of the present disclosure provide a multi-stage incremental sheet forming method that includes identifying, by at least one control unit, a convex hull of a target structure to be formed by a forming tool, operating, by the at least one control unit, the forming tool according to a first tool path relative to the initial structure to form an intermediate structure having a shape based on the convex hull of the target structure, and operating, by the at least one control unit, the forming tool according to a second tool path relative to the intermediate structure to form one or more inward features in the intermediate structure to form the target structure, wherein the second tool path is different from the first tool path. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 illustrates a schematic block diagram of a multi-stage incremental sheet forming system according to one embodiment of the present disclosure. [Figure 2] 1 illustrates a flowchart of a multi-stage incremental sheet forming method according to one embodiment of the present disclosure. [Figure 3] 1 shows a perspective view of a target structure according to one embodiment of the present disclosure. [Figure 4] 4 shows a perspective view of an intermediate structure having a shape based on the convex hull of the target structure of FIG. 3 according to one embodiment of the present disclosure. [Figure 5] 5 shows a perspective view of a forming tool operating according to a first tool path to form the intermediate structure of FIG. 4. [Figure 6] 4 shows a perspective view of a forming tool operating according to a second tool path to form the target structure of FIG. 3. [Figure 7] 1 shows a perspective view of a target structure according to one embodiment of the present disclosure. [Figure 8] 8 shows a perspective view of an intermediate structure shaped as a convex hull of the target structure of FIG. 7 according to one embodiment of the present disclosure. [Figure 9] 9 shows a perspective view of a forming tool operating according to a first tool path to form the intermediate structure of FIG. 8; [Figure 10] 8 shows a perspective view of a forming tool operating according to a second tool path to form the target structure of FIG. 7. [Figure 11] 1 shows a perspective view of a target structure according to one embodiment of the present disclosure. [Figure 12] 12 shows a perspective view of an intermediate structure shaped as a convex hull of the target structure of FIG. 11 according to one embodiment of the present disclosure. [Figure 13] 1 shows a perspective view of a target structure according to one embodiment of the present disclosure. [Figure 14] 14 shows a perspective view of an intermediate structure shaped as a convex hull of the target structure of FIG. 13 according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0018] The foregoing summary, as well as the following detailed description of certain embodiments, will be better understood when read in conjunction with the accompanying drawings. As used herein, the use of "a" or "an" in the singular does not necessarily exclude a plurality of such elements or steps. Furthermore, references to "one embodiment" should not be interpreted as excluding the existence of additional embodiments that incorporate the features described herein. Furthermore, unless expressly stated otherwise, embodiments "including" or "having" one or more elements having a particular condition may include additional elements that do not have that condition.

[0019] Certain embodiments of the present disclosure provide a multi-stage incremental sheet forming system and method. The multi-stage incremental sheet forming system and method include a first forming operation to form an intermediate structure having a shape based on a convex hull of a target structure. For example, the intermediate structure may be formed as a convex hull of the target structure. The intermediate structure is formed via a forming tool operating according to a first tool path (e.g., through a predetermined tool path having a start point and an end point). After the intermediate structure having a shape based on the convex hull of the target structure is formed, the forming tool operates according to a second tool path (e.g., through a predetermined tool path having a start point and an end point) different from the first tool path to form inward features within the intermediate structure (e.g., the convex hull of the target structure) to form the target structure.

[0020] To avoid potential damage risks from steep walls (e.g., walls having an angle greater than 60 degrees relative to the horizontal), embodiments of the present disclosure form structures in two stages. In at least one embodiment, the first stage involves a forming tool traversing along a Z-level tool path to form a convex hull of the target structure. The second stage involves a forming tool traversing along a striped tool path to form the target structure, which may include one or more inward-facing features. Thus, embodiments of the present disclosure can form a variety of structures with steeply angled walls via an incremental sheet forming process.

[0021] 1 illustrates a schematic block diagram of a multi-stage incremental sheet forming system 100, according to one embodiment of the present disclosure. In at least one embodiment, the incremental sheet forming system 100 includes a tool path generation control unit 102 that communicates with a construction database 104, such as via one or more wired or wireless connections. The tool path generation control unit 102 may also communicate with a user interface 106, such as via one or more wired or wireless connections. The tool path generation control unit 102 may be co-located with one or both of the construction database 104 and / or the user interface 106. Optionally, the tool path generation control unit 102 may be located remotely from one or both of the construction database 104 and / or the user interface 106.

[0022] The incremental sheet forming system 100 also includes a forming tool or machine 108 configured to operate to form the structure 110. In at least one embodiment, the forming tool 108 is a forming stylus having a rounded, blunt working end 112 configured to apply a force on the structure 110 to form various features (curves, bends, notches, etc.) in and / or on the structure 110. The forming tool 108 operates on the structure 110 according to a tool path 114 (e.g., through a predetermined tool path having a start point and an end point) to form the structure 110 of a desired shape.

[0023] In at least one embodiment, structure 110 is an initial structure such as a blank piece of metal (such as an alloy of aluminum, titanium, copper, etc.) For example, the initial structure may be a flat, planar piece of metal supported on a die.

[0024] In at least one embodiment, the tool path generation control unit 102 communicates with the forming tool 108, such as via one or more wired or wireless connections. The tool path generation control unit 102 is configured to operate the forming tool 108 to form a target structure of a desired shape formed from an initial structure, such as, for example, sheet metal.

[0025] The structure database 104 stores various data. For example, the structure database 104 stores target data 116. The target data 116 includes information about the target or desired structure to be formed. For example, the target data 116 may include a discrete geometric definition, such as a tessellation of the target structure to be formed, which may include one or more inward-facing features. They may be in the format of, for example, an STL, PLY, or VRML file. Optionally, the target data 116 may include a set of surfaces, curves, and points with adjusted parameters. They may be in the format of, for example, a STEP, SAT, Parasolids, or IGES file.

[0026] The user interface 106 includes a display 118, which may include one or more interface devices such as a monitor, television, touch screen, keyboard, mouse, etc. The user interface 106 and the tool path generation control unit 102 may be part of a computer workstation, for example. In at least one other embodiment, the tool path generation control unit 102 and the user interface 106 may be part of a handheld device, such as a smart tablet, smartphone, laptop computer, etc.

[0027] In operation, the tool path generation control unit 102 identifies the size and shape of the target structure via the target data 116. For example, the target data 116 may include information regarding the size, shape, and characteristics of the target structure, as described above. In at least one embodiment, the target data 116 may include geometric data of the target structure, geometric data of the convex hull structure, manufacturing process data, and tool path data.

[0028] The tool path generation control unit 102 analyzes target data 116 related to target structures (e.g., a geometric definition of the target structures) and identifies a convex hull of such target structures. For example, in at least one embodiment, the tool path generation control unit 102 includes a convex hull identification module 120 that analyzes target data related to the target structures (e.g., a tessellation of the target structures) and identifies a convex hull of the target structures.

[0029] The convex hull of a set of points S is the smallest convex set that contains the set of points S. For a target structure, the convex hull is the smallest convex set that contains all of the points of the target structure. In an embodiment, the tool path generation control unit 102 is configured to identify the convex hull of the target structure based on the smallest convex set that contains all of the points of the target structure. The convex hull (C) of a set of points is the set of all possible convex combinations of the points in the set, as expressed by the following mathematical formula: TIFF0007759732000001.tif34170

[0030] After the tool path generation control unit 102 identifies the convex hull of the target structure, the tool path generation control unit 102 operates the forming tool 108 against the structure 110 (e.g., a blank piece of metal) according to a first tool path to form an intermediate structure based on the convex hull of the target structure. Within the example, the shape of the intermediate structure to be formed is selected based on the convex hull of the target structure. In at least one embodiment, the intermediate structure has a shape based on the convex hull of the target structure. For example, in at least one embodiment, the tool path generation control unit 102 includes a convex hull tool path generation module 122 (which may also be referred to as a first tool path generation module) that identifies a first tool path based on the identified convex hull (and may then save the tool path, such as an ASCII text file, which may be in a format such as G-Code or APTSource), and operates the forming tool 108 to form an intermediate structure (e.g., having a shape based on the convex hull of the target structure) that is shaped based on the convex hull of the target structure. In at least one embodiment, the first tool path is a Z-level tool path for the forming tool 108.

[0031] In at least one other embodiment, the intermediate structure is shaped to resemble the convex hull of the target structure. For example, an intermediate structure shaped based on the convex hull of the target structure may include one or more inward-facing or partially formed inward-facing features that the convex hull would not normally include.

[0032] After the tool path generation control unit 102 operates or provides instructions to operate the forming tool 108 to form the intermediate structure, the forming tool 108 operates on the intermediate structure in accordance with the instructions to traverse a second tool path to form various features of the target structure relative to the intermediate structure to form the target structure from the intermediate structure. The second tool path is different from the first tool path. For example, in at least one embodiment, the tool path generation control unit 102 includes or is otherwise in communication with a target structure tool path generation module 124 (which may also be referred to as a second tool path generation module) that identifies the second tool path based on a tessellation of the target structure, which may include inward features to be formed. A control unit operably coupled to the forming tool 108, such as the tool path generation control unit 102 or a separate, different forming control unit 103, operates the forming tool 108 to form the target structure from the intermediate structure. In at least one embodiment, the second tool path is a striped tool path for the forming tool 108.

[0033] As described herein, in one example, the forming control unit 103 receives instructions and commands from the tool path generation control unit 102 to operate the forming tool 108. As another optional example, the tool path generation control unit 102 can directly operate the forming tool 108. In at least one embodiment, the tool path generation control unit 102 and the forming control unit 103 can be separate and distinct control units. As another example, the tool path generation control unit 102 and the forming control unit 103 can be part of a common processing or control system or unit. For example, the tool path generation control unit 102 and the forming control unit 103 can be part of an integrated chip, processing device, or the like.

[0034] In an embodiment, when the tool path generation control unit 102 operates the forming tool 108 to form a target structure from the intermediate structure, the forming tool 108 forms one or more inward features in the intermediate structure having a shape based on the convex hull of the target structure. Thus, in an embodiment, the inward features are formed after the convex hull is formed. The target structure is not formed in a single stage. In a single stage, the forming tool 108 operates on the structure according to a single tool path to form the target structure. Instead, the forming tool 108 first operates on an initial structure (such as a blank piece of metal) according to a first tool path (e.g., operating the forming tool 108 through a predetermined tool path having a start point and an end point) to first form an intermediate structure having a shape based on the convex hull of the target structure. After the intermediate structure is formed, the forming tool 108 subsequently operates on the intermediate structure according to a second tool path to form one or more inward features in the intermediate structure (e.g., within and / or on the intermediate structure) to form the target structure. By first forming the convex hull and subsequently forming the inward features within the convex hull, embodiments of the present disclosure result in less material being too thin and less risk of material damage, even when portions of the structure are at steep angles (as opposed to single-pass incremental sheet forming processes, which can damage steep walls when forming the inward features).

[0035] Inward features are features formed in the outer wall of a structure. For example, inward features include notches, cavities, depressions, channels, recesses, grooves, creases, pockets, insets, holes, and the like.

[0036] As described herein, the multi-stage incremental sheet forming system 100 includes a forming tool 108 and a tool path generation control unit 102 in communication with the forming tool 108 (whether directly and / or via a forming control unit 103). The tool path generation control unit 102 is configured to identify a convex hull of a target structure to be formed by the forming tool 108 (e.g., a convex hull of a geometric representation of the target structure). The tool path generation control unit 102 is configured to operate the forming tool 108 according to a first tool path relative to an initial structure (e.g., a blank piece of sheet metal, such as structure 110) to form an intermediate structure that is shaped based on the convex hull of the target structure (e.g., shaped as the convex hull of the target structure). The tool path generation control unit 102 is further configured to operate the forming tool 108 according to a second tool path relative to the intermediate structure to form one or more inward features in the intermediate structure to form the target structure.

[0037] 2 illustrates a flowchart of a multi-stage incremental sheet forming method according to one embodiment of the present disclosure. In at least one embodiment, one or more control units, such as the tool path generation control unit 102 and the forming control unit 103, operate according to the flowchart shown and described with respect to FIG.

[0038] 1 and 2, at 200, the tool path generation control unit 102 identifies the convex hull of the target structure. For example, the tool path generation control unit 102 (e.g., the convex hull identification module 120) analyzes the target data 116, which includes a geometric representation of the target structure, and identifies the convex hull of the target structure (i.e., identifies the convex hull of the geometric representation of the target structure).

[0039] At 202, an intermediate structure is formed that is based on or shaped as the convex hull of the target structure. For example, the tool path generation control unit 102 (e.g., convex hull tool path generation module 122) outputs instructions to operate the forming tool 108 according to (e.g., traverse along) a first tool path on an initial structure (e.g., a blank piece of metal) to form an intermediate structure having a shape based on the convex hull of the target structure.

[0040] If the intermediate structure is successfully formed (e.g., the convex hull of the target structure is completely formed), the method proceeds to 206, where one or more inward-facing features are formed for the intermediate structure. For example, the tool path generation control unit 102 (e.g., the target structure tool path generation module 124) outputs instructions to operate the forming tool 108 according to a second tool path on the intermediate structure to form the inward-facing feature(s). If all of the inward-facing features of the target structure have been formed for the intermediate structure, the method proceeds to 210, where the target structure is formed.

[0041] As used herein, terms such as "control unit," "central processing unit," "CPU," "computer," and the like may include any processor-based or microprocessor-based system, including systems that use microcontrollers, reduced instruction set computers (RISKs), application specific integrated circuits (ASICs), logic circuits, and any other circuits or processors, including hardware, software, or a combination thereof, capable of performing the functions described herein. The above examples are illustrative only and, thus, are not intended to limit in any way the definition and / or meaning of such terms. For example, the tool path generation control unit 102 and the forming control unit 103 may be or include one or more processors configured to control their operation as described herein.

[0042] A module is one or more portions of a control unit. For example, a module may be part of a chip, a circuit, a processor, etc. As another example, a module may be a chip, a circuit, a processor, etc. In general, a module may be a sub-control unit. For example, convex hull identification module 120, convex hull tool path generation module 122, and target structure tool path generation module 124 are components of tool path generation control unit 102.

[0043] The tool path generation control unit 102 and the forming control unit 103 are configured to execute a set of instructions stored in one or more data storage units or elements (e.g., one or more memories) to process data. For example, the tool path generation control unit, the tool path generation control unit 102, and the forming control unit 103 may include or be coupled to one or more memories. The data storage units may also store data or other information as desired or needed. The data storage units may take the form of an information source or a physical memory element within a processing machine. The one or more data storage units or elements may comprise volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. By way of example, non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), and / or flash memory. Volatile memory may include random access memory (RAM), which may act as external cache memory. The data store of the disclosed systems and methods is intended to include, without being limited to, these and any other suitable types of memory.

[0044] The set of instructions may include various commands that instruct the tool path generation control unit 102 and the forming control unit 103 as processing machines to perform specific operations, such as the methods and processes of various embodiments of the subject matter described herein. The set of instructions may take the form of a software program. The software may take various forms, such as system software or application software. Furthermore, the software may take the form of a collection of separate programs, a program subset within a larger program, or a portion of a program. The software may also include modular programming in the form of object-oriented programming. The processing of input data by the processing machine may be in response to user commands, in response to results of previous processing, or in response to a request made by another processing machine.

[0045] The drawings of the embodiments herein illustrate one or more control or processing units, such as the tool path generation control unit 102 and the forming control unit 103. It should be understood that the processing or control unit may represent circuitry, or portions thereof, that may be implemented as hardware having associated instructions (e.g., software stored on a tangible, non-transitory computer-readable storage medium, such as a computer hard drive, ROM, RAM, etc.) that perform the operations described herein. The hardware may include state machine circuitry hardwired to perform the functions described herein. Optionally, the hardware may include electronic circuitry including and / or connected to one or more logic-based devices, such as a microprocessor, processor, controller, etc. Optionally, the tool path generation control unit 102 and the forming control unit 103 may represent processing circuitry, such as one or more of a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), microprocessor(s), etc. The circuitry in various embodiments may be configured to execute one or more algorithms to perform the functions described herein. One or more algorithms, whether or not explicitly identified in a flowchart or method, may include aspects of the embodiments disclosed herein.

[0046] As used herein, the terms "software" and "firmware" are interchangeable and include any computer program stored in a data storage unit (e.g., one or more memories) for execution by a computer, including RAM memory, ROM memory, EPROM memory, EEPROM memory, and non-volatile RAM (NVRAM) memory. The types of data storage units listed above are merely exemplary and thus not limiting as to the types of memory that may be used for storing computer programs.

[0047] FIG. 3 illustrates a perspective view of a target structure 300 according to one embodiment of the present disclosure. The target structure 300 is a structure desired to be formed. In at least one embodiment, the target structure 300 includes one or more walls 302. In at least one embodiment, the target structure 300 includes one or more walls 302 that collectively form at least one arcuate cavity inward-facing feature 306. In one example, the walls 302 are oriented at an angle relative to a reference plane 304 of 40 degrees or greater (e.g., 60 degrees or greater) relative to the target structure 300. For example, the reference plane 304 is a reference plane (such as the X-Y plane) that is perpendicular to the Z axis in a Cartesian coordinate system. In one example, the portion of at least one wall 302 corresponding to the inward-facing feature 306 includes one or more portions oriented at an angle relative to the reference plane 304 of 60 degrees or greater.

[0048] The target structure 300 includes at least one inward-facing feature 306 inset into at least one wall 302. For example, the inward-facing feature 306 may be or include an inset 307, such as an inwardly directed feature. As shown, the inward-facing feature 306 includes a pocket 309 that faces inward from an outer envelope 308 of the wall 302. The outer envelope 308 is the outermost surface of the wall 302.

[0049] 1 and 3, the target data 116 includes information about the target structure 300. For example, the target data 116 includes information about the size, shape, and inward feature(s) 306 of the target structure 300. In at least one embodiment, the structure database 104 also stores manufacturing data (such as may be included in the target data 116 or stored separately). The manufacturing data includes information about the process, such as tool type, tool shape, tool size, and tool feed rate.

[0050] 4 shows a perspective view of an intermediate structure 400 shaped as a convex hull of target structure 300 (shown in FIG. 3), according to one embodiment of the present disclosure. As shown, intermediate structure 400 is a convex hull of target structure 300.

[0051] 1, 3, and 4, tool path generation control unit 102 identifies a convex hull of target structure 300. Tool path generation control unit 102 then identifies a first tool path based on the convex hull of target structure 300. Forming control unit 103 then operates according to the first tool path on an initial structure (such as structure 110 shown in FIG. 1) to form intermediate structure 400.

[0052] The intermediate structure 400, which is a convex hull of the target structure 300, is devoid of inward-facing features 306. For example, the wall 402 of the intermediate structure 400 is smooth without any inward-facing features.

[0053] Figure 5 shows a perspective view of the forming tool 108 operating according to a first tool path 500 to form the intermediate structure 400 of Figure 4. With reference to Figures 1 and 5, the first tool path 500 may be a Z-level tool path, in which the forming tool 108 engages (e.g., is driven into) the initial structure 110 at a horizontal or Z level 502 to form the intermediate structure 400, which is a convex hull of the target structure 300 (shown in Figure 3). Adjacent Z levels 502 are separated by a predetermined spacing 504.

[0054] FIG. 6 shows a perspective view of the forming tool 108 operating according to a second tool path 600 to form the target structure of FIG. 3 . Referring to FIGS. 1 and 6 , the second tool path 600 may be a striped tool path that cycles back and forth in a direction indicated by arrow A above the intermediate structure (e.g., an X or Y direction perpendicular to the Z direction) to form the inward feature(s) 306. The Z-level path of the first tool path 500 (shown in FIG. 5 ) moves along a contour in the X-Y plane while incrementally progressing in the Z direction. Meanwhile, the striped path of the second tool path 600 moves back and forth in an alternating, side-to-side (or end-to-end) manner while incrementally progressing in the X direction. The forming tool 108 operates according to the second tool path 600 after the intermediate structure 400 (shown in FIG. 4 ) is formed, thereby forming the inward feature(s) 306 in the intermediate structure 400 and forming the target structure 300.

[0055] 7 illustrates a perspective view of a target structure 700 according to one embodiment of the present disclosure. The target structure 700 is a structure desired to be formed. In at least one embodiment, the target structure 700 has one or more walls 702 that collectively form at least one inward-facing feature 706, illustrated as an arcuate cavity. As one example, the wall 702 encompasses a maximum wall angle of 60 degrees or greater relative to a reference plane 704.

[0056] The target structure 700 includes at least one inward-facing feature 706 formed in at least one wall 702. As shown, the inward-facing feature 706 includes a notch 707 having a crease 709 and one or more depressions 711 facing inward from an outer envelope 708 of the wall 702.

[0057] 8 shows a perspective view of an intermediate structure 800 shaped as a convex hull of target structure 700 (shown in FIG. 7), according to one embodiment of the present disclosure. As shown, intermediate structure 800 is a convex hull of target structure 700.

[0058] Intermediate structure 800, which is a convex hull of target structure 700, lacks inward-facing features 706. For example, wall 802 of intermediate structure 800 is smooth without any inward-facing shapes corresponding to inward-facing features 706 of target structure 700.

[0059] Figure 9 shows a perspective view of the forming tool 108 operating according to a first tool path 900 to form the intermediate structure 800 of Figure 8. With reference to Figures 1 and 9, the first tool path 900 may be a Z-level tool path, in which case the forming tool 108 engages (e.g., is driven into) the structure 110 at a vertical or Z-level to form the intermediate structure 800.

[0060] FIG. 10 shows a perspective view of the forming tool 108 operating according to a second tool path 1000 to form the target structure. Referring to FIGS. 1 and 10 , the second tool path 1000 may be a striped tool path that cycles back and forth in a direction indicated by arrow A above the intermediate structure (e.g., in the X or Y direction perpendicular to the Z direction) to form the inward feature(s) 706. The Z-level path of the first tool path 900 (shown in FIG. 9 ) moves along the contour in the X-Y plane while incrementally progressing in the Z direction. Meanwhile, the striped path of the second tool path 1000 moves back and forth in an alternating, side-to-side (or end-to-end) manner while incrementally progressing in the X direction. After the intermediate structure 800 (shown in FIG. 8 ) is formed, the forming tool 108 operates according to the second tool path 1000, thereby forming the inward feature(s) 706 in the intermediate structure 800 and forming the target structure 700.

[0061] 11 shows a perspective view of a target structure 1100 according to one embodiment of the present disclosure. The target structure 1100 includes a plurality of inward-facing features 1102, such as grooves 1101, channels 1103, and recesses 1105 between peaks 1104.

[0062] Figure 12 shows a perspective view of an intermediate structure 1200 shaped as a convex hull of the target structure 1100 of Figure 11, according to one embodiment of the present disclosure. The intermediate structure 1200 lacks the inward-facing features 1102 shown in Figure 11.

[0063] 13 shows a perspective view of a target structure 1300 according to one embodiment of the present disclosure. The target structure 1300 includes a plurality of inwardly facing features 1302, such as holes or central passages 1304 and outer cutouts 1306.

[0064] Figure 14 shows a perspective view of an intermediate structure 1400 shaped as a convex hull of the target structure 1300 of Figure 13, according to one embodiment of the present disclosure. The intermediate structure 1400 lacks the inward-facing features 1302 shown in Figure 13.

[0065] Figures 3, 7, 11, and 13 show examples of target structures, while Figures 4, 8, 12, and 14 each show examples of intermediate structures that represent the convex hull of the aforementioned target structures. It should be understood that such target structures and intermediate structures are merely exemplary. The target structures may be sized and shaped differently and may have more or fewer inwardly facing features (shaped as shown or shaped differently than shown). Accordingly, the associated intermediate shapes selected based on the convex hull of the target structures may be sized and shaped differently than shown.

[0066] 1-14 , embodiments of the present disclosure provide systems and methods that enable a computing device to quickly and efficiently analyze large amounts of data. For example, a target structure may include thousands, if not millions, of points connected together by polygons, such as triangles. Furthermore, operating a forming tool to accurately form intermediate and target structures may not be efficiently performed manually. Therefore, large amounts of data are analyzed, and the operation of the forming tool 108 is automatically performed based on the analysis. As described above, very large amounts of data are efficiently organized and / or analyzed by the tool path generation control unit 102. The tool path generation control unit 102 further operates and / or outputs instructions to operate the forming tool 108. The tool path generation control unit 102 analyzes the data, generates a first tool path, forms the intermediate structure, generates a second tool path, and forms the target structure in a relatively short amount of time to quickly and efficiently identify the size and shape of the intermediate structure. A human would not be able to efficiently analyze such a large amount of data in such a short amount of time. Thus, embodiments of the present disclosure provide improved and efficient functionality and overwhelmingly superior performance to humans analyzing vast amounts of data.

[0067] In at least one embodiment, components of the multi-stage incremental sheet forming system 100, such as the tool path generation control unit 102, provide and / or enable a computer system to operate as a dedicated computer system for the incremental sheet forming process.

[0068] As described herein, embodiments of the present disclosure provide systems and methods for forming structures with steep walls (e.g., walls angled at 60 degrees or greater) via incremental sheet forming. Additionally, embodiments of the present disclosure provide incremental sheet forming systems and methods that are less vulnerable to damaging (e.g., breaking) structural materials at steep angles (e.g., 60 degrees or greater).

[0069] For purposes of describing embodiments of the present disclosure, various spatial and directional terms may be used, such as top, bottom, lower, center, sideways, horizontal, vertical, front, etc., but it should be understood that such terms are used only relative to the orientation shown in the drawings. The orientation may be flipped, rotated, or otherwise changed so that top becomes bottom and bottom becomes top, horizontal becomes vertical, etc.

[0070] As used herein, a structure, limitation, or element that is "configured to" perform a task or operation is structurally shaped, configured, or adapted to specifically correspond to the task or operation. For clarity and to avoid doubt, an object that is merely modifiable to perform a task or operation is not "configured to" perform a task or operation as used herein.

[0071] It should be understood that the above description is intended to be illustrative, not limiting. For example, the above-described embodiments (and / or aspects thereof) may be used in combination with each other. In addition, many modifications can be made to the teachings of various embodiments to adapt to particular situations or materials without departing from their scope. While the geometries and types of materials described herein are intended to define the parameters of various embodiments of the present disclosure, these embodiments are exemplary rather than limiting. Many other embodiments will be apparent to those skilled in the art upon review of the present invention. The scope of the various embodiments of the present disclosure should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the words "including" and "in which" are used as plain-English equivalents of the words "comprising" and "wherein," respectively. Furthermore, the words "first," "second," "third," etc. are used merely as labels and are not intended to impose numerical requirements on their objects. Moreover, the following claim limitations are not stated in means-plus-function form and are not intended to be construed under 35 U.S.C. §112(f) unless such claim limitations expressly use the phrase "means for" followed by a recitation of function lacking further structure.

[0072] Furthermore, the present disclosure includes embodiments according to the following clauses: Article 1. a forming tool (108), and A multi-stage incremental sheet forming system (100) comprising at least one control unit (102) in communication with the forming tool (108), the at least one control unit (102) is configured to determine a convex hull of a target structure (300, 700, 1100) to be formed by the forming tool (108); the at least one control unit (102) is configured to operate the forming tool (108) according to a first tool path (114) relative to the initial structure (110) to form an intermediate structure (400, 800, 1400) having a shape based on the convex hull of the target structure (300, 700, 1100); A multi-stage incremental sheet forming system (100), wherein the at least one control unit (102) is configured to operate the forming tool (108) according to a second tool path (114) different from the first tool path (114) relative to the intermediate structure (400, 800, 1400) to form one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100). Article 2. The at least one control unit (102) a tool path generation control unit (102) configured to identify at least one tool path (114) and the convex hull of the target structure (300, 700, 1100); and 2. The multi-stage incremental sheet forming system (100) of claim 1, comprising a forming control unit (103) configured to operate said forming tool (108). Article 3. The multi-stage incremental sheet forming system (100) described in clause 1 or 2, wherein the at least one control unit (102) comprises a tool path generation control unit (102) configured to identify the convex hull of the target structure (300, 700, 1100) based on the smallest convex set that encompasses all points of the target structure (300, 700, 1100). Article 4. A multi-stage incremental sheet forming system (100) as described in any one of clauses 1 to 3, further comprising a structural database (104) in communication with the at least one control unit (102), the structural database (104) storing target data (116) including information regarding the size of the target structure, the shape of the target structure, the one or more inward features (306, 706, 1302) of the target structure (300, 700, 1100), and manufacturing data including tool shape, tool size, and tool feed rate. Article 5. The multi-stage incremental sheet forming system (100) described in any one of clauses 1 to 4, wherein the at least one control unit (102) comprises a tool path generation control unit (102) including a convex hull identification module (120) that analyzes target data (116) related to the target structure (300, 700, 1100) and identifies the convex hull of the target structure (300, 700, 1100) based on the target data (116). Article 6. The multi-stage incremental sheet forming system (100) described in any one of clauses 1 to 5, wherein the at least one control unit (102) comprises a tool path generation control unit (102) including a convex hull tool path generation module (122) that identifies the first tool path (114) based on the identified convex hull, and a forming control unit (103) operates the forming tool (108) according to the first tool path (114) relative to the initial structure (110) to form the intermediate structure (400, 800, 1400) having the shape based on the convex hull of the target structure (300, 700, 1100). Article 7. 7. The multi-stage incremental sheet forming system (100) of any one of clauses 1 to 6, wherein the first tool path (114) is a Z-level (502) tool path (114). Article 8. The multi-stage incremental sheet forming system (100) described in any one of clauses 1 to 7, wherein the at least one control unit (102) comprises a tool path generation control unit (102) including a target structure tool path generation module (124) configured to perform one or both of operating or outputting instructions for operating the forming tool (108) according to the second tool path (114) relative to the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100) and to form the one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400). Article 9. 9. The multi-stage incremental sheet forming system (100) of any one of clauses 1 to 8, wherein the second tool path (114) is a striped tool path (114). Article 10. The multi-stage incremental sheet forming system (100) of any one of clauses 1 to 9, wherein the one or more inward features (306, 706, 1302) include one or more of at least one notch (707), at least one cavity, at least one depression (711), at least one channel (1103), at least one recess (1105), at least one groove (1101), at least one fold (709), at least one pocket (309), at least one inset (307), or at least one hole (1304). Article 11. 11. The multi-stage incremental sheet forming system (100) of any one of clauses 1 to 10, wherein the target structure (300, 700, 1100) comprises at least one wall positioned at an angle of at least 60 degrees relative to the horizontal. Article 12. 12. The multi-stage incremental sheet forming system (100) of any one of clauses 1 to 11, wherein the intermediate structure (400, 800, 1400) is devoid of the one or more inwardly facing features (306, 706). Article 13. determining, by at least one control unit (102), a convex hull of a target structure (300, 700, 1100) to be formed by a forming tool (108); operating, by the at least one control unit (102), the forming tool (108) according to a first tool path (114) relative to the initial structure (110) to form an intermediate structure (400, 800, 1400) having a shape based on the convex hull of the target structure (300, 700, 1100); and and operating, by the at least one control unit (102), the forming tool (108) relative to the intermediate structure (400, 800, 1400) according to a second tool path (114) different from the first tool path (114) to form one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100). Article 14. 14. The multi-stage incremental sheet forming method of claim 13, further comprising storing target data (116) in a structure database (104) including information regarding a geometric representation of the target structure (300, 700, 1100), including the one or more inwardly facing features (306, 706, 1302) of the target structure (300, 700, 1100). Article 15. 15. The multi-stage incremental sheet forming method of claim 13 or 14, wherein said identifying comprises identifying the convex hull of the target structure (300, 700, 1100) by a convex hull identification module (120). Article 16. 16. The multi-stage incremental sheet forming method of any one of clauses 13 to 15, wherein operating the forming tool (108) according to the first tool path (114) by the at least one control unit (102) includes operating the forming tool (108) according to the first tool path (114) relative to the initial structure (110) by a convex hull tool path generation module (122) to form the intermediate structure (400, 800, 1400) having the shape based on the convex hull of the target structure (300, 700, 1100). Article 17. 17. The multi-stage incremental sheet forming method of any one of clauses 13 to 16, wherein the first tool path (114) is a Z-level (502) tool path (114) and the second tool path (114) is a striped tool path (114). Article 18. 18. The multi-stage incremental sheet forming method of any one of clauses 13 to 17, wherein operating the forming tool (108) according to the second tool path (114) by the at least one control unit (102) comprises operating the forming tool (108) according to the second tool path (114) relative to the intermediate structure (400, 800, 1400) to form the one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100) by a target structure tool path generation module (124). Article 19. 19. The multi-stage incremental sheet forming method of any one of clauses 13 to 18, wherein the one or more inward features (306, 706, 1302) comprise one or more of at least one notch, at least one cavity, at least one depression (711), at least one channel (1103), at least one recess (1105), at least one groove (1101), at least one fold (709), at least one pocket (309), at least one inset (307), or at least one hole (1304). Article 20. 20. The multi-stage incremental sheet forming method of any one of clauses 13 to 19, wherein the target structure (300, 700, 1100) comprises at least one wall positioned at an angle of at least 60 degrees relative to a reference plane (304, 704). Article 21. 21. The multi-stage incremental sheet forming method of any one of clauses 13 to 20, wherein the intermediate structure (400, 800, 1400) is devoid of the one or more inwardly facing features (306, 706). Article 22. Forming tools (108), at least one control unit (102) in communication with said forming tool (108); and A multi-stage incremental sheet forming system (100) comprising a structural database (104) in communication with the at least one control unit (102), the structure database (104) stores target data (116) including information regarding a geometric representation of a target structure (300, 700, 1100) and one or more inwardly directed features (306, 706, 1302) of the target structure (300, 700, 1100), the one or more inwardly directed features (306, 706, 1302) including one or more of at least one notch, at least one cavity, at least one depression (711), at least one channel (1103), at least one recess (1105), at least one groove (1101), at least one fold (709), at least one pocket (309), at least one inset (307), or at least one hole (1304); The at least one control unit (102) a convex hull identification module (120) configured to identify a convex hull of a target structure (300, 700, 1100) formed by the forming tool (108); a convex hull tool path generation module (122) configured to perform one or both of operating and outputting instructions for operating the forming tool (108) according to a Z-level (502) tool path (114) relative to an initial structure (110) to form an intermediate structure (110, 400) having a shape based on the convex hull of the target structure (300, 700, 110), wherein the intermediate structure (400, 800, 1400) lacks the one or more inward-facing features (306, 706); and A multi-stage incremental sheet forming system (100) comprising a target structure tool path generation module (124) configured to perform one or both of operating the forming tool according to a striped tool path (114) relative to the intermediate structure (400, 800, 1400) and outputting instructions for operating the forming tool to form the one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100).

[0073] The written description uses examples to disclose various embodiments of the present disclosure, including the best mode, and to enable any person skilled in the art to practice various embodiments of the present disclosure, including making and using any device or system, and performing any methods incorporated therein. The patentable scope of various embodiments of the present disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if the examples have structural elements that do not differ from the literal language of the claims, or if the examples include equivalent structural elements that differ only insignificantly from the literal language of the claims.

Claims

1. a forming tool (108), and A multi-stage incremental sheet forming system (100) comprising at least one control unit (102) in communication with said forming tool (108), the at least one control unit (102) is configured to determine a convex hull of a target structure (300, 700, 1100) formed by the forming tool (108); the at least one control unit (102) is configured to operate the forming tool (108) according to a first tool path (114) relative to the initial structure (110) to form an intermediate structure (400, 800, 1400) having a shape based on the convex hull of the target structure (300, 700, 1100); The at least one control unit (102) is configured to operate the forming tool (108) according to a second tool path (114) different from the first tool path (114) relative to the intermediate structure (400, 800, 1400) to form the target structure (300, 700, 1100) and to form one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400).

2. The at least one control unit (102) a tool path generation control unit (102) configured to identify at least one tool path (114) and the convex hull of the target structure (300, 700, 1100); and The multi-stage incremental sheet forming system (100) of claim 1, comprising a forming control unit (103) configured to operate the forming tool (108).

3. 3. The multi-stage incremental sheet forming system (100) of claim 1 or 2, wherein the at least one control unit (102) comprises a tool path generation control unit (102) configured to identify the convex hull of the target structure (300, 700, 1100) based on the smallest convex set that encompasses all points of the target structure (300, 700, 1100).

4. 4. The multi-stage incremental sheet forming system of claim 1, further comprising a structure database in communication with the at least one control unit, the structure database storing target data including information regarding the size of the target structure, the shape of the target structure, the one or more inward features of the target structure, and manufacturing data including tool shape, tool size, and tool feed rate.

5. 5. The multi-stage incremental sheet forming system of claim 1, wherein the at least one control unit comprises a tool path generation control unit including a convex hull identification module that analyzes target data related to the target structure and identifies the convex hull of the target structure based on the target data.

6. 6. The multi-stage incremental sheet forming system of claim 1, wherein the at least one control unit comprises a tool path generation control unit including a convex hull tool path generation module that identifies the first tool path based on the identified convex hull, and a forming control unit operates the forming tool according to the first tool path relative to the initial structure to form the intermediate structure having the shape based on the convex hull of the target structure.

7. 7. The multi-stage incremental sheet forming system of claim 1, wherein the at least one control unit comprises a tool path generation control unit including a target structure tool path generation module configured to perform one or both of operating or outputting instructions for operating the forming tool according to the second tool path relative to the intermediate structure to form the target structure and to form the one or more inward features in the intermediate structure.

8. 8. The multi-stage incremental sheet forming system (100) of claim 1, wherein the one or more inward features (306, 706, 1302) comprise one or more of at least one notch (707), at least one cavity, at least one depression (711), at least one channel (1103), at least one recess (1105), at least one groove (1101), at least one fold (709), at least one pocket (309), at least one inset (307), or at least one hole (1304).

9. 9. The multi-stage incremental sheet forming system (100) of claim 1, wherein the target structure (300, 700, 1100) comprises at least one wall disposed at an angle of at least 60 degrees relative to the horizontal.

10. determining, by at least one control unit (102), a convex hull of a target structure (300, 700, 1100) to be formed by a forming tool (108); operating, by the at least one control unit (102), the forming tool (108) according to a first tool path (114) relative to the initial structure (110) to form an intermediate structure (400, 800, 1400) having a shape based on the convex hull of the target structure (300, 700, 1100); and and operating, by the at least one control unit (102), the forming tool (108) relative to the intermediate structure (400, 800, 1400) according to a second tool path (114) different from the first tool path (114) to form the target structure (300, 700, 1100) and to form one or more inward features (306, 706, 1302) in the intermediate structure (400, 800, 1400).

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