Robotic surgery enables doctors to perform complex medical procedures with greater precision, control, and flexibility. According to the Mayo Clinic, the benefits of robot-assisted surgery include less pain and blood loss, quicker recovery times, and smaller scars. These minimally-invasive procedures can also reduce the rate of complications such as surgical site infections. With today’s surgical robots, doctors can even acquire high-definition views using imaging technologies that are superior to the naked eye.
3D printing, a form of additive manufacturing, can support robot-assisted surgery, but not all 3D printers can achieve the high precision that’s required. Within robotic assemblies, 3D printed components need tight tolerances for parts mating. Microscale part sizes and ultra-high resolution and accuracy are also needed for some applications, such as soft robotic endoscopes. Complex 3D printed parts with small features can support minimally-invasive procedures, but that’s not all there is to consider.
For applications where there is contact with soft tissue, 3D printed parts for surgical robots need to use materials that are biocompatible and sterilizable. The surfaces to these high precision components need to be smooth, and designers want the freedom to integrate 3D printed parts with non-3DP components like sensors and actuators. According to the National Center for Biotechnology Information, most surgical robots that use additive manufacturing do so for complex, compact, and customizable parts.
PµSL 3D Printing for Surgical Robotics
When the first surgical robot, the PUMA 560, was developed in the 1980s, micro injection molding and CNC machining were the main ways to prototype and produce high-precision parts. Because of their tooling costs and turnaround times, however, these traditional forms of manufacturing limited the speed and scope of innovation. Rapid prototyping for patient-specific solutions was especially impractical since high volumes of parts are needed to amortize the cost of tooling.
Today, 3D printing with Projection Micro Stereolithography (PµSL) is helping to advance surgical robotics. PµSL technology combines ultra-high precision, resolution, and accuracy with the use of biocompatible materials that can undergo sterilization. Importantly, PµSL fabricates parts for surgical robots at significantly faster speeds than traditional microfabrication techniques. Other forms of 3D printing can also eliminate the need for tooling, but PµSL works at the microscale with top-notch resolution.
During PµSL 3D printing, a photosensitive liquid resin is exposed to ultraviolet (UV) light so that the rapid photopolymerization of an entire resin of resin occurs. Two-photon polymerization (TPP-DLW), another 3D printing technology, can also produce small parts in ultra-high precision, but it’s a much slower process. Traditional stereolithography (SLA) can’t produce high-precision parts at all, and fused deposition modeling (FDM) is limited to low-precision parts with rough surfaces.
High Precision 3D Printed Parts for Surgical Robots
Surgical robots have two main applications for high-precision 3D printed parts: scopes and surgical instruments. Scopes consist of a tiny camera attached to a long, thin tube that moves through a body passageway or opening. Surgical instruments can include scopes, but this category of 3D printed parts encompasses many other types of devices that are held in a robot’s end effector, which allows the surgical robot to interact with the patient.
For both types of surgical robotics applications, PµSL technology can produce microscale parts at sub-millimeter resolutions. For example, when the University of Leeds needed soft scopes, Dr. James Chandler achieved what he calls “fantastic results” with the MicroArch® S140, a 10µm series 3D printer from Boston Micro Fabrication (BMF). BMF’s ultra-high resolution 3D printers can also extend the applications of surgical robotics with support for surgical instruments such as microneedles, and with applications that include sensors and microelectronics.
Today, BMF is the only company in the world to provide a 3D printing solution that matches precision injection molding in terms of resolution, size and tolerance. BMF’s microscale 3D printers also rival traditional microfabrication techniques in terms of surface quality, which is important for surgical robotics and other applications that require smooth surfaces. “When we get the parts of the printer,” Dr. Chandler of the University of Leeds says, “they feel just like injection molded parts”.
To learn more about high precision 3D printed parts for surgical robotics, contact BMF.
