The MechProcessor: Helping Novices Design Printable Mechanisms Across Different Printers

Abstract

Additive manufacturing (AM), or 3D-printing, sits at the heart of the Maker Movement—the growing desire for wider-ranges of people to design physical objects. However, most users that wish to design functional moving devices face a prohibitive barrier-to-entry: they need fluency in a computer-aided design (CAD) package. This limits most people to being merely consumers, rather than designers or makers. To solve this problem, we combine advances in mechanism synthesis, computer languages, and design for AM to create a computational framework, the MechProcessor, which allows novices to produce 3D-printable, moving mechanisms of varying complexity using simple and extendable interfaces. The paper describes how we use hierarchical cascading configuration languages, breadth-first search, and mixed-integer linear programming (MILP) for mechanism synthesis, along with a nested, printable test-case to detect and resolve the AM constraints needed to ensure the devices can be 3D printed. We provide physical case studies and an open-source library of code and mechanisms that enable others to easily extend the MechProcessor framework. This encourages new research, commercial, and educational directions, including new types of customized printable robotics, business models for customer-driven design, and STEM education initiatives that involve nontechnical audiences in mechanical design. By promoting novice interaction in complex design and fabrication of movable components, we can move society closer to the true promise of the Maker Movement: turning consumers into designers.

How Additive Manufacturing Technology Changes Business Models? – Review of Literature

“…Today's consumer-grade equipment is mainly based on the cheapest available plastic printing technology 2 one-color objects with relatively good mechanical properties [1], and a varying dimensional accuracy [86] requiring nuanced variable optimization (e.g., humidity, room airflows) for acceptable printing results [29]. Implementing full-fledged, complex 3DP-designs requires new types of skills and engineering software [8], [15], [53], [71] and for this purpose [86], [87] formulate ideas of easy-to-use design software.…”

Direct Digital Subtractive Manufacturing of a Functional Assembly Using Voxel-Based Models

“…The AM process limited them to use clearances above 0.4 mm to avoid problems such as friction, release (of moving parts), and removal of support materials. A similar work was done by Fuge et al [17], who developed the MECHPROCESSOR software application to help novices search for and print mechanisms. Another approach utilizing the advantages of AM in minimizing assembly is to embed external components (such as circuits or metal parts within SLA) during the deposition process [18].…”

Interactive robogami: An end-to-end system for design of robots with ground locomotion

“…Although fabrication plans for fully functional robots were presented in Mehta et al (2014), the designs were driven by mechanical considerations, and the electrical and software components generated in a post-processing stage. On the other side of the spectrum are studies in generating driving mechanisms that match desired input motions for toy designs (Coros et al, 2013; Thomaszewski et al, 2014; Zhu et al, 2012), robots (Megaro et al, 2015; Song et al, 2015), and other models (Fuge et al, 2015). The combined geometry-motion design challenge, although acknowledged, is not addressed by these systems.…”

“…Unlike traditional manufacturing, in which complex geometries require in-depth analysis to ensure fabricability (Gupta and Nau, 1995), 3D printing processes are independent of the fabricated object, meaning that designers are able to instantiate increasingly complex geometries without corresponding increases in cost or fabrication time. As a result, a number of groups have started to investigate how mechanisms and linkages can be fabricated as single prints without requiring post-fabrication assembly by printing joints (Cal et al, 2012; Fuge et al, 2015), full mechanisms (Thomaszewski et al, 2014)), and robots (Mavroidis et al, 2000; Megaro et al, 2015). However, when it comes to evaluation and design cycles, current design tools still present users with clear limitations, and the learning curve is steep for anyone who wishes to create a design from scratch.…”