A research team at Concordia University has introduced a new sound-based 3D printing approach that could reshape how tiny, high-performance components are made for healthcare and robotics. The method, called proximal sound printing (PSP), uses focused ultrasound to solidify liquid polymers with dramatically improved control—delivering prints that are up to 10 times more precise than earlier acoustic 3D printing techniques.
The work, published in the journal Microsystems & Nanoengineering, builds on the group’s earlier “direct sound printing” concept, which showed that ultrasound can trigger sonochemical reactions to cure polymers on demand. That original approach was a major step forward, but it often ran into common micro-manufacturing problems: inconsistent results, limited resolution, and difficulty producing reliably small features.
PSP tackles these issues with a deceptively simple shift—bringing the sound source much closer to the printing surface. By moving into this “proximal” range, the researchers can focus the ultrasound more tightly, improving stability and enabling finer details. Another key advantage is efficiency: the closer configuration achieves this higher precision while using significantly less power, which matters for scaling the technology for real-world manufacturing and lab use.
What makes sound-based 3D printing especially exciting is what it doesn’t rely on. Unlike many conventional 3D printers that need heat or light to cure materials, ultrasound curing can be more compatible with soft polymers. That includes silicone and similar flexible materials widely used in next-generation devices—such as lab-on-a-chip platforms, wearable tech, and soft robotics—where small size and material softness are essential, but difficult to achieve with standard micro-scale printing methods.
The research was led by PhD graduate Shervin Forough alongside Professor Muthukumaran Packirisamy and Mohsen Habibi, with support from the Natural Sciences and Engineering Research Council. Looking ahead, the team expects proximal sound printing to speed up prototyping and production for miniaturized medical diagnostic tools and soft robotic parts, offering a faster and more versatile route for building advanced microscale systems—without being limited to the material and process constraints of traditional 3D printing.
