A new open-source software is shaking up the way engineers design and print multi-material objects.
Charles Wade, a PhD student in computer science at the University of Colorado Boulder, has developed OpenVCAD, a design system that goes beyond traditional modeling by using code to map not just shapes but also the distribution of materials within 3D objects.
Created in the Matter Assembly Computation Lab led by Assistant Professor Robert MacCurdy, the tool enables engineers to design spatially varying multi-material objects with remarkable ease and precision.
The project reflects a growing interest in computational approaches that merge coding with design, a shift that could transform additive manufacturing.
“There’s certainly a history of multi-material design study and practice that existed well before OpenVCAD,” said MacCurdy, who is also affiliated with the departments of computer science and 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 multi-material designs.”
Breaking CAD boundaries
Designing multi-material objects has long tested the limits of conventional computer-aided design (CAD) tools. Traditional systems typically define an object’s outer boundaries, assuming that the interior is made of a single material.
That approach falls short when engineers need to model gradient designs: objects that transition smoothly between materials, like a running shoe sole that shifts from firm at the bottom to soft at the top. Without specialized tools, creating such seamless transitions can be nearly impossible.
That’s where OpenVCAD comes in. The software allows users to combine complex mathematical functions and assign them as materials to different regions of a 3D object.
“This is the first multi-material, code-based design tool that is widely available,” said Wade.
“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.”
From lab to every industry
The research team demonstrated OpenVCAD’s versatility across a variety of 3D printers, including one in MacCurdy’s lab capable of printing with up to five materials simultaneously.
The implications stretch far beyond academia. From medical modeling to soft robotics and structural simulation, the software can support engineers and researchers across fields.
Surgeons could use it to create lifelike anatomical models for surgical planning. Robotics researchers might rely on it to design flexible actuators that bend in one direction but stay rigid in another.
And structural engineers can apply unique mechanical properties to specific parts of complex lattice structures to enhance strength and impact absorption.
“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.”
True to its name, OpenVCAD is fully open-source. It comes with a Python implementation, allowing users to import the repository and begin designing with 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.”