Rob MacCurdy

New open-source software allows for efficient 3D printing with multiple materials

Alexander James Servantez — Mon, 13 Oct 2025 21:16:15 +0000

New open-source software allows for efficient 3D printing with multiple materials Alexander Jame… Mon, 10/13/2025 - 15:16

Alexander Servantez

A new open-source tool is reshaping how engineers design multi-material objects.

Charles Wade, a fourth-year PhD student in the Department of Computer Science at CU Boulder, has created a design system software package that uses functions and code to map not just shapes, but where different materials belong in a 3D object.

OpenVCAD, a new open-source tool created to help engineers efficiently design multi-material objects.

The project, called OpenVCAD, was developed in the Matter Assembly Computation Lab led by Assistant Professor Robert MacCurdy of the Paul M. Rady Department of Mechanical Engineering. The team is publishing a new paper in the top 3D printing journal Additive Manufacturing on October 13 that will highlight the design tool and its potential to transform 3D printing by enabling engineers to design multi-material objects smarter and more efficiently.

“There’s certainly a history of multi-material design study and practice that existed well before OpenVCAD,” said MacCurdy, who is also affiliated with computer science and the Department of Electrical, Computer and Energy Engineering. “But we believe the overhead of writing specific code for specific projects every single time prevents engineers from doing as much design as they could.

“With OpenVCAD, we’re doing all of that work once—and doing it really well—so that people have built-in infrastructure to represent these spatially varying multimaterial designs.”

Pushing the limits of multi-material design

Designing objects with multiple materials has long pushed the limits of conventional computer-aided design (CAD) software.

According to Wade and MacCurdy, traditional design tools tend to represent objects as boundary surfaces only. This means they operate with an implicit assumption that everything inside of a boundary surface is all made up of the same material.

One of the major areas of interest in mechanics is something called gradient design, in which two materials are gradually blended together from one to another—like a shoe sole that shifts from firm at the bottom to soft at the top. But without a powerful design tool, translating rough steps into smooth transitions can be overwhelmingly difficult.

That’s why Wade developed OpenVCAD. The software package acts almost as a set of convenience tools that allow people not only to easily compose complex functions, but also to assign them as materials to objects in a 3D printer.

“This is the first multi-material, code-based design tool that is widely available,” Wade said. “It allows for good complexity when printing objects, it’s accessible and it’s intuitive to write and design. Unlike traditional CAD software, where you’re forced to sketch everything out for each change and you cannot represent graded materials, our tool allows users to change one small variable and watch the whole design update in an easy way.”

A broad impact for all to explore

The team’s new paper will explore OpenVCAD’s capability across a variety of 3D printers, including one available to MacCurdy’s lab group that allows for object printing with up to five materials at a time.

However, it’s the project’s potential impact for the entire engineering community that excites them.

A multi-material scan-to-print medical model for pre-surgical planning.

According to MacCurdy and his team, the OpenVCAD software can be used to help researchers design objects relevant to just about any industry and field. Surgeons in need of realistic planning models to practice on can take advantage of the tool’s gradient mixing properties. Soft robotics experts can use it to create flexible actuators that bend in one direction, but remain straight and stiff in another. Engineers who need to simulate complex multimaterial objects can design in OpenVCAD and easily export a simulation-ready file.

OpenVCAD can even apply specific mechanical properties to specific parts of lattice structures, which are often used for impact-absorbing capabilities to achieve more complicated designs. The possibilities are endless.

“We’re able to rely on OpenVCAD’s core capabilities to represent multi-material objects in a bunch of different domains,” said MacCurdy. “But there is a lot more coming in certain areas that we are excited about and we’re really hoping this approach to multi-material design takes off.”

OpenVCAD is a completely open-source tool, meaning it is widely available for engineers around the world to use. It even comes equipped with a Python implementation so that any user can easily import the team’s repository and get to work with just a single line of code.

“We want this to be widely available to people,” Wade said. “We have a growing base of external researchers from other institutions who are using this tool and we hope to enable that community to do their best work.”

Assistant Professor Robert MacCurdy and fourth-year PhD student Charles Wade have created an open-source design system software package that uses functions and code to map not just shapes, but where different materials belong in a 3D object. The project, called OpenVCAD, has the potential to transform 3D printing by enabling engineers to design multi-material objects smarter and more efficiently.

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A multi-material lattice structure with a gradient design used for its impact-absorbing capabilities.

How to print a robot from scratch: Combining liquids, solids could lead to faster, more flexible 3D creations

Anonymous — Mon, 18 Apr 2022 20:53:57 +0000

How to print a robot from scratch: Combining liquids, solids could lead to faster, more flexible 3D creations Anonymous (not verified) Mon, 04/18/2022 - 14:53

Professor Robert MacCurdy has developed a new way to 3D-print liquid and solid materials together, potentially leading to more dynamic and useful products—from robots to wearable electronic devices.

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A new design workflow for an integral piece of soft robotic systems

Anonymous — Wed, 08 Sep 2021 19:09:23 +0000

A new design workflow for an integral piece of soft robotic systems Anonymous (not verified) Wed, 09/08/2021 - 13:09

Pneumatic Soft Actuators Project Video

[video:https://www.youtube.com/watch?v=re_9QF8w0bk&t=2s]

A Department of Mechanical Engineering student-written paper that presents an innovative workflow for designing and fabricating pneumatic soft actuators has won the IEEE-CASE Best Application Paper Award at the 2021 CASE Conference in Lyon, France.

The award recognizes the significance of new applications on technical merit, originality, impact on the field and clarity of presentation. The accolade comes with a $1,000 prize to be shared by all authors.

PhD students Lawrence Smith and Travis Hainsworth, graduate student Zachary Jordan and Professor Robert MacCurdy co-authored the paper—titled “A Seamless Workflow for Design and Fabrication of Multimaterial Pneumatic Soft Actuators.” High School Research Assistant Xavier Bell is a co-author as well.

Pneumatic soft actuators are a fundamental part of soft robotic systems. We asked Smith about their project and the team's future plans.

Lawrence Smith, Dpt. of Mechanical Engineering PhD student

Question: How would you describe the results of this work?

Answer: In this paper, we introduce design tools that our lab developed to help soft robotics students enter the field. We noticed that designing, simulating and fabricating soft robots is a time-intensive and manual process, which typically requires multi-domain expertise. Our paper introduces a seamless workflow for designing soft robots that uses an intuitive graphical user interface for design and visualization, and automates the trickiest parts of the process – interfacing with finite element software and preparing designs for 3D printing.

Question: Was there a particular aspect of this work that was hard to complete?

Answer: The trickiest part of this work was building an approachable and intuitive interface for our design tools. We wanted to create software that is enjoyable to play and explore with to encourage students to discover new designs, without being bogged down in unnecessary complexity.

Question: What's next with this project?

Answer: We plan to build on this research by migrating these design tools from their current embodiment – a MATLAB App – to a public website. That way anyone can access our design tools on the web without downloading and installing any software.

Question: What are you and your co-authors’ plans for the $1,000 prize?

Answer: 3D printer filament, probably!

Smith, Hainsworth, Jordan and MacCurdy developed the novel workflow in MacCurdy’s Matter Assembly Computation Lab at CU Boulder’s Department of Mechanical Engineering.

Three mechanical engineering students and Professor Robert MacCurdy developed the novel workflow and published it in a paper that won the IEEE-CASE Best Application Paper Award at the 2021 CASE Conference in France.

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New healthcare-related grants enable research into pandemics, rheumatoid arthritis

Anonymous — Fri, 04 Dec 2020 00:35:41 +0000

New healthcare-related grants enable research into pandemics, rheumatoid arthritis Anonymous (not verified) Thu, 12/03/2020 - 17:35

The AB Nexus Research Collaboration Grant program announced its inaugural round of grants totaling $625,000 for novel research projects integrating expertise from the CU Anschutz and CU Boulder campuses. Three of these projects were born out of the Paul M. Rady Department of Mechanical Engineering.

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Infectious disease containment, anxiety disorder interventions among collaborative projects funded by AB Nexus grants

Anonymous — Fri, 20 Nov 2020 07:00:00 +0000

Infectious disease containment, anxiety disorder interventions among collaborative projects funded by AB Nexus grants Anonymous (not verified) Fri, 11/20/2020 - 00:00

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