BASF and UC-San Diego have developed an innovative 3D printing method for pneumatically-driven soft robots with integrated control circuits.
By utilizing Fused Filament Fabrication (FFF) and special design techniques, highly functional grippers were created that ensure safe interaction between robots and humans.
The monolithic 3D printing process enables efficient production of autonomous pneumatic devices with various applications in fields such as manufacturing and farming.
BASF and UC-San Diego achieve breakthrough in 3D printing method for pneumatically-driven soft robots with integrated control circuits.
Monolithic pneumatic soft robot with integrated controls, created through innovative 3D printing technology; Image: BASF
A global collaboration between BASF and the University of California (UC) San Diego has resulted in an innovative method for the monolithic 3D printing of pneumatically-driven soft robots with sensing and feedback capabilities.
Facilitated by BASF's California Research Alliance (CARA), the research project led by Yichen Zhai, Albert de Boer, Martin Faber, Rohini Gupta, and Michael T. Tolley has successfully fabricated highly functional grippers with embedded fluidic control circuits using Ultrafuse® TPU and Fused Filament Fabrication (FFF). This approach not only created complex and fully functional devices but also improved the safety of soft robots when interacting with humans.
Traditional soft robots are typically manufactured through molding and assembly processes, which involve numerous manual operations and limit complexity. By utilizing desktop FFF-based 3D printing, the team achieved an accessible alternative that reduces manual labor and enables the creation of more intricate structures.
Overcoming the challenges of high effective stiffness and potential leaks in FFF-printed soft robots, the team devised an innovative design for fabricating soft, airtight, and pneumatic robotic devices, incorporating actuators with embedded fluidic control components.
By employing this approach, the team successfully printed actuators that were ten times softer than previous FFF-produced ones, capable of bending into a complete circle, as well as pneumatic valves for controlling high-pressure airflow with low control pressure.
Through the integration of actuators and valves, the team demonstrated a monolithically printed, electronics-free autonomous gripper. This gripper maintained the airtightness and soft actuation performance of each component while being manufactured in a single 3D printing workflow, taking only 16 hours and 19 minutes. The fabrication process required no post-treatment, assembly, or repairs, ensuring high repeatability and accessibility.
The developed approach can be extended to the design and fabrication of various pneumatic devices with embedded sensing and control circuits. Key design rules for achieving airtight structures involve printing them using a single, continuous toolpath known as an Eulerian path. Additionally, creating structures with thin walls, approximately two traces thick, yields low stiffness comparable to silicone-molded parts.
The monolithic autonomous gripper, fabricated through an uninterrupted 3D printing workflow, was immediately ready for use. Designed to autonomously grasp and release objects with simple controls, it holds potential as a manipulation tool in various applications such as manufacturing and farming.
The entire fabrication process, including design and printing, can be easily replicated using similar desktop 3D printers, without the need for manual operations like assembly or adjustment. The predefined toolpath rules ensured consistency in working performance and airtight quality across all parts and the combined system.
Building upon the fabrication method, as well as the actuator and valve designs, the collaboration between BASF and UC-San Diego has pioneered a unique approach enabled by 3D printing. The developed design rules have successfully enabled the creation of airtight, high-performance, and autonomous pneumatic devices. With different combinations of these "building blocks," customized complex robots can be designed and manufactured using monolithic printing processes.
