SYSTEM AND METHODS FOR ADDITIVE MANUFACTURING OF ELECTROMECHANICAL ASSEMBLIES

Abstract

A hybrid additive manufacturing approach that incorporates three-dimensional (3D) printing and placement of modules selected from a library of modules to fabricate an electromechanical assembly. By virtue of fabrication of the electromechanical assembly, mechanical properties and electrical properties of the assembly are created. The invention overcomes the material and process limitations of current printable electronics approaches, enabling complete, complex electromechanical assemblies to be fabricated.

Claims

1. A method for fabricating an electromechanical assembly, comprising the steps of: depositing by a first device a first material into a plurality of stacked regions, each successive region positioned on top of the previous region, the plurality of stacked regions forming a base region comprising one or more void elements; selecting by a second device one or more module components from a library of module components; positioning by the second device each of the one or more module components into a portion of the one or more void elements of the base region portion such that the module components are adjacent one another, the base region portion and one or more module components creating both mechanical properties and electrical properties of the electromechanical assembly.

2. The method for fabricating an electromechanical assembly according to claim 1 wherein the first device is a 3D printing machine.

3. The method for fabricating an electromechanical assembly according to claim 1 wherein the second device is a pick-and-place machine.

4. The method for fabricating an electromechanical assembly according to claim 1 wherein the first material is a photopolymer material.

5. The method for fabricating an electromechanical assembly according to claim 1 wherein each module component includes an electrical element selected from the group comprising: 2-way connect, 4-way connect, crossover connect, resistor, capacitor, inductor, diode, transistor, switch, and microcontroller.

6. The method for fabricating an electromechanical assembly according to claim 1 wherein the positioning step further comprises the step of applying heat by a third device to fuse the module components to one another.

7. The method for fabricating an electromechanical assembly according to claim 6 wherein the third device is a laser sintering machine.

8. An electromechanical assembly comprising: a base region portion comprising a first plurality of successive material region, wherein the first plurality of successive material region forms one or more void elements; one or more module components positioned adjacent to one another in the one or more void elements; and a top region portion comprising a second plurality of successive material regions, wherein the second plurality of successive material regions encapsulates the one or more module components.

9. The electromechanical assembly according to claim 8 wherein each module component comprises a tile element with an electrical element positioned on a surface or within a surface of the tile element.

10. The electromechanical assembly according to claim 9 wherein the tile element is a rectangular parallelepiped shape.

11. The electromechanical assembly according to claim 10 wherein the tile element is a 3 millimeter (mm) square shape with a thickness of 0.9 millimeters (mm).

12. The electromechanical assembly according to claim 9 wherein the electrical element is selected from the group of electrical elements comprising: 2-way connect, 4-way connect, crossover connect, resistor, capacitor, inductor, diode, transistor, switch, and microcontroller.

13. A system for fabricating an electromechanical assembly, comprising: a printing apparatus that deposits a first material into a plurality of stacked regions, the plurality of stacked regions forming a base region portion comprising one or more void elements; a module library comprising a plurality of module components, each module component comprising a tile element including an electrical element and mechanical element positioned on or within a surface of the tile element; a component placement apparatus that selects from the module library one or more module components, the component placement apparatus further positions the one or more module components into a portion of the one or more void elements of the base region portion such that the module components are adjacent one another, the base region portion and one or more module components creating both mechanical properties and electrical properties of the electromechanical assembly.

14. The system for fabricating an electromechanical assembly according to claim 13 further comprising a fusion device for fusing the module components together.

15. The system for fabricating an electromechanical assembly according to claim 14 wherein the fusion device is a laser sintering machine.

16. The method for fabricating an electromechanical assembly according to claim 1 wherein each module component comprises a top surface that includes one or more pads.

17. The method for fabricating an electromechanical assembly according to claim 16 wherein each module component comprises a bottom surface that includes one or more pads.

18. The method for fabricating an electromechanical assembly according to claim 17 wherein a via connects the one or more pads of the top surface and the one or more pads of the bottom surface.

19. The electromechanical assembly according to claim 8 wherein each module component comprises one or more pads on a top surface or a bottom surface of the module component.

20. The system for fabricating an electromechanical assembly according to claim 13 wherein each module component comprises one or more pads on a top surface or a bottom surface of the module component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The preferred embodiments of the invention will be described in conjunction with the appended drawings provided to illustrate and not to the limit the invention, where like designations denote like elements, and in which:

[0038] FIG. 1 illustrates a block diagram of an exemplary system for fabricating an electromechanical assembly according to the invention.

[0039] FIG. 2 illustrates a perspective view of a module component according to the invention.

[0040] FIG. 3 illustrates schematic diagrams of select module components according to the invention.

[0041] FIG. 4 illustrates a flow chart of an exemplary method for fabricating an electromechanical assembly according to the invention.

[0042] FIG. 5 illustrates a graphic representation for fabricating an electromechanical assembly according to the invention.

DETAILED DESCRIPTION

[0043] The invention demonstrates a capability that is impossible with contemporary electronics printing methods, and would require a costly electrical and mechanical design cycle, along with special-purpose tooling if it were produced following conventional electromechanical fabrication practice.

[0044] The invention is directed to a hybrid approach that incorporates three-dimensional (3D) printing and placement of modules selected from a library of modules to fabricate an electromechanical assembly with both mechanical functionality and electrical functionality comparable to conventionally produced planar printed circuit boards.

[0045] FIG. 1 illustrates a block diagram of an exemplary system 100 for fabricating an electromechanical assembly according to the invention. The system 100 facilitates a hybrid approach that incorporates devices such as a printing apparatus 120 and a component placement apparatus 140 to fabricate an electromechanical assembly 200. The printing apparatus 120 may include any type of printing functionality such as a 3D printing machine. The component placement apparatus 140 may include any type of selection and placement of components such as a high speed pick-and-place machine including with parallel pick-and-place techniques, or other similar techniques. Parallel fabrication methods may be used to exploit the mechanical regularity of the modules to manipulate entire regions simultaneously.

[0046] The printing apparatus 120 may access a material library 110 to obtain the material for printing. The material library 110 may include one or more different types of materials that may be printed, for example, photopolymers or thermoplastics, although any type of material may be used that is capable of being deposited by a 3D printing machine, including for example an inkjet process. The component placement apparatus 140 may access a module library 130 for selection of module components for positioning within the material printed by the printing apparatus 120. The module library may include different generic, prefabricated module components that vary in electrical functionality and/or mechanical functionality. Representative module components are more fully described in reference to FIG. 2 and FIG. 3 below.

[0047] In certain embodiments, a fusion device 160 such as a laser sintering machine may fuse the module components to one another in order to form an electrical connection in order to realize electrical properties. It is also contemplated the fusion device 160 may be used to fuse the module components to the material printed by the printing apparatus 120.

[0048] In addition to the module components including mechanical properties and/or electrical properties, the combination of material printed from the printing apparatus 120 and module components selected and placed by the component placement apparatus 140 create the electromechanical assembly 200 with both mechanical properties and electrical properties. Mechanical properties include, for example, stiffness, strength, stress, and strain. Electrical properties include any control of electrical energy such as circuits including, for example, resistivity and conductivity.

[0049] FIG. 2 illustrates a perspective view of a module component 200 according to the invention. Each module component 200 comprises a tile element 202 comprising a plurality of surfaces. As illustrated, the tile element 202 is generally square in shape, but any shape is contemplated. For example, the tile element may be circular, spherical, or rectangular parallelepiped, to name a few examples. In one specific embodiment, the tile element 202 is a 3 millimeter (mm) square shape with a thickness of 0.9 millimeters (mm) in order to allow easy scaling to higher levels of additive manufacturing. However, the invention is applicable to module components of any size that are amenable to manipulation using a component placement apparatus.

[0050] The tile element 202 includes one or more pads 205 that may be used for connections. The pads 205 are shown on a top surface of the module component 202, but pads may also be located on the surface opposing the top surface. As an example, pad on the top surface may be connected to pads on the bottom surface by a via in each pad. It is also contemplated that the pads may provide programming signals, enabling the printing apparatus 120 (FIG. 1) to individually program each module.

[0051] An electrical element 204 and/or a mechanical element 206 may be either positioned on a surface of the tile element 202 or within a surface of the tile element 202 in order to create functionality/propertieselectrical/mechanicalfor the prefabricated module component 200 for entry into the module library 130 (FIG. 1). The surface opposing the surface that includes the electrical element 204 and/or a mechanical element 206 is generally planar. Electrical elements 204 control electrical energy and may include, for example, 2-way connect, 4-way connect, crossover connect, resistor, capacitor, inductor, diode, transistor, switch, and microcontroller, as seen schematically in FIG. 3. Mechanical elements 206 control mechanical energy and may include any working or moveable function, such as a gripper or robot effector.

[0052] FIG. 3 illustrates schematic diagrams of select module components 204 according to the invention. As shown more specifically in FIG. 3, a blank module component 210 does not include an electrical element or mechanical element. Module component 212 illustrates a 2-way connect. Module component 214 illustrates a 4-way connect. Module component 216 illustrates a crossover connect. Module component 218 illustrates a resistor. Module component 220 illustrates a capacitor. Module component 222 illustrates an inductor. Module component 224 illustrates a diode, specifically a Light Emitting Diode (LED). Module component 226 illustrates a switch. Module component 228 and module component 230 illustrate transistors, specifically a p-channel field-effect transistor (P-FET) and a n-channel field-effect transistor (N-FET), respectively. Module component 227 illustrates a microcontroller.

[0053] The system and methods according to the invention were used to fabricate a 2.5-D interconnection in which neighboring modules on the same region rely on offset modules above or below for electrical connections. Electrical circuits are formed by creating chains of modules on 2 or more regions. This approach allows new modules to be added to an assembly at any vacant location, avoiding interference fits that would otherwise require high-precision placement or large mating forces. This 2.5-D interconnection strategy is one of several contemplated topologies; other strategies compatible with this invention include full 3D interconnections (in-plane connections between modules).

[0054] It is contemplated that all modules may share the same mechanical interface, for example 3 mm square, 0.9 mm thick, with four square pads on the top and bottom. These dimensions are incidental, as they are driven by the printed circuit board fabrication methods employed to produce the modules. The invention is equally applicable to smaller modules produced via micro-fabrication, with the added capability of embedding the electronic functionality within, rather than on top of, each module.

[0055] With the exception of the blank module 210 of FIG. 3), the topside pads of each module are connected to their corresponding bottom side pads by a via in each pad. Eight of the module types implement carrier boards for commercially available electronic components, breaking out disparate package connections into a common format. While some modules support electrical elements 204 (FIG. 2) positioned on or within their top side, certain modules may not have components on or within their bottom side in order to facilitate automated manipulation. In alternate embodiments, the electrical elements 204 and/or mechanical elements 206 may be positioned on or within one or more surfaces of the module component 200.

[0056] In particular embodiments, the FET modules 228, 230 support drain currents in excess of 3 A and can be used with signals as fast as 10 Megahertz (MHz). The microcontroller module 232 employs an Atmel ATtiny10 that contains 1 kB of code space, 32 bytes of RAM, an analog to digital converter, internal oscillators, and timer circuitry. This module's pads may also provide programming signals, enabling the printer to individually program each microcontroller module as it is placed.

[0057] FIG. 4 and FIG. 5 illustrate exemplary methods for fabricating an electromechanical assembly according to the invention. Specifically, FIG. 4 is a flow chart and FIG. 5 is a graphic representation.

[0058] As shown in FIG. 4 at step 402, material is selected and deposited into a plurality of stacked regions, each successive region positioned on top of the previous region. At step 404, module components are are selected from a library of modules. The module components are positioned into the material at step 406. In certain embodiments, the module components may be fused together or fused to the material as shown in step 408. At step 410, mechanical properties and electrical properties are created by virtue of fabrication of the electromechanical assembly.

[0059] FIG. 5 illustrates a graphic representation for fabricating an electromechanical assembly. As shown in FIG. 5, step A is directed to a first device 120 depositing material 122, for example using an inkjet process, into a plurality of stacked regions 502a with each successive region positioned on top of the previous region. The plurality of stacked regions 502a forms a base region portion 510a including one or more void elements 520 as constructed by the material 122 such as a photopolymer material.

[0060] As shown by step B, a second device 140 such as a high speed pick-and-place machine, selects a module component 240 from the library of module components and positions the module component 240 in one of void elements 522, 524.

[0061] Step C illustrates both module components 240, 242 positioned within the base region portion 510a. Step D illustrates a second plurality of stacked regions 502b forming a top region portion 510b deposited by the inkjet 3D printing machine 120. The top region portion 510b encapsulates all or a portion of the module components 240, 242 while forming void element 526.

[0062] As shown by step E, the high speed pick-and-place machine 140 selects module component 244 and positions it in void element 526.

[0063] In certain embodiments, a fusion device 160 as shown in step F, such as a laser sintering machine, applies heat in the form of a laser beam 162 in order to fuse the module components 240, 242, 244 to one another. The laser sintering machine 160 may also apply heat to fuse the module components 240, 242, 244 to a region portion 510a, 510b.

[0064] As shown in step G, material is deposited into a third plurality of stacked regions 502c with each successive region positioned on top of the previous region. The plurality of stacked regions 502c forms a second top region portion 502c that encapsulates all of the module components 240, 242, 244 forming an electromechanical assembly 550. By virtue of fabrication of the electromechanical assembly 550, mechanical properties and electrical properties of the assembly are created.

[0065] The system and methods of the invention may be used to fabricate any type of assembly, for example an LED keychain light, activated when a button is depressed on the surface. The system and methods of the invention may be used to fabricate assemblies that exploit the programmability provided by a microcontroller module.

[0066] For example, a microcontroller module may be programmed to create specific pulse-trains such as those that correspond to the on and on-off pulses in a particular infra-red (IR) remote control protocol. These pulses can be used to turn an IR LED on and off, controlling a remote device. Another example includes the play/pause, jog forward, jog backward, volume up and volume down functions, creating a 5-channel IR remote control. Each of the assemblies employ the inkjet-printed material as a supportive structure, and the remote utilizes a flexible material around the buttons that allows motion during button-press events.

[0067] Another example of an assembly incorporates a LED into a structure that has full electromechanical functionality. Inkjet-produced areas can incorporate components such as rack-and-pinion connections, captive hinges, and springs. When one component is activated, one or more other components may be activated. For example, when a component on a gripper is activated, the gripper arms open and an internal switch closes, activating an illumination component.

[0068] While the disclosure is susceptible to various modifications and alternative forms, specific exemplary embodiments of the invention have been shown by way of example in the drawings and have been described in detail. It should be understood, however, that there is no intent to limit the disclosure to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure as defined by the appended claims.