On July 30, 2023, Antarctic Bear learned that a research team from BASF's California Research Alliance (CARA) and the University of California, San Diego (UC) has revolutionized soft robotics. Researchers Yichen Zhai, Albert de Boer, Martin Faber, Rohini Gupta, and Michael T. Tolley have successfully fabricated a monolithic soft robotic device on a desktop 3D printer embedded with fluid control circuits. This project uses Fused Filament Fabrication (FFF) technology and Ultrafuse TPU material to build innovative grippers, a material composition that guarantees safety when people use them.
Full details of this research can be found in a recently published cover article in Science Robotics, title_d "Desktop fabrication of monolithic soft robotic devices with embedded fluidic control circuits/Desktop-scale fabrication of monolithic soft robotic devices with embedded fluidic control circuits ".
Compared to traditional soft robots that rely on pneumatic actuation and manufacturing methods that involve hand molding/assembly, these new devices are fabricated using 3D printing, reducing the need for manual work and allowing the creation of more complex structures.
A common challenge encountered with FFF-printed soft robots is their highly effective stiffness and potential leakage, which can limit their functionality. To address these issues, the researchers came up with an ingenious design to produce soft, leak-proof pneumatic robotic devices, embedding fluid control components into the actuators during the printing process. They achieved softer actuators that can bend to form a full circle and printed pneumatic valves that can control high-pressure airflow.
The team further combined these actuators and valves to create an electronics-free autonomous gripper. What's remarkable about the device is that it was produced in a continuous 3D printing workflow that lasted 16 hours and 19 minutes. The final product requires no post-processing, assembly, or repair – ensuring a high degree of repeatability and accessibility.
The same fabrication strategy can be extended to other pneumatic devices with embedded sensing and control circuits. Key design rules include printing with a single continuous toolpath, known as an Euler path, and creating structures with ultra-thin walls. This results in a low stiffness structure, comparable to silicone molded parts.
The jig produced is ready to use immediately after printing, with the ability to automatically pick up and release objects. It can be easily replicated using similar desktop 3D printers, making it an attractive tool for various industries, including manufacturing and agriculture.
The collaboration between BASF and UC San Diego not only resulted in innovative manufacturing methods but also established new design rules, resulting in high-performance, airtight autonomous pneumatic devices. This advance heralds a new era of soft robotics, where complex custom robots can be designed and produced in a single monolithic printing process.
