3D Printing Emerges as Key Fabrication Technology for Soft Robotics

Rajesh Uppal June 22, 2024 AI & IT, Manufacturing, Mechanical Comments Off on 3D Printing Emerges as Key Fabrication Technology for Soft Robotics 454 Views

Introduction:

In recent years, the field of soft robotics has experienced remarkable growth, thanks to advancements in fabrication technologies. Among these, 3D printing has emerged as a game-changer, offering unparalleled capabilities in creating complex, customizable soft robotic systems. With its ability to produce high-quality structures and simultaneously print multiple materials, 3D printing is revolutionizing the way soft robots are designed and manufactured.

Soft robotics represents a groundbreaking advancement in the field of robotics, offering a paradigm shift from the rigid, mechanical structures of traditional robots to pliable, flexible systems that mimic biological organisms. Unlike their conventional counterparts, soft robots lack hard internal structures and instead rely on a combination of muscularity and deformation to grasp objects and move autonomously.

Powered by pressurized air or liquids rather than motors or gears, these robots exhibit a remarkable degree of flexibility and adaptability, making them ideal for a wide range of applications, from exploration missions in space to biomedical devices for healthcare. In many cases soft robotics designs mimic natural, evolved biological forms hence also called bio-inspired robots. This, combined with their soft exteriors, can make soft robots more suitable for interaction with living things or even for use as human exoskeletons.

The US Military is seeking to harness the flexibility of invertebrate creatures to produce robots that benefit from less structural rigidity than what robotics currently allows for. The results suggest a 3D printed robotic squid may be among the next generation of military robots. These robots would be better equipped for working in cramped spaces, using range of movement rather than sheer propelling force.

High-Quality Fabrication:

One of the key enabling technologies driving the development of soft robotics is three-dimensional (3D) printing. This revolutionary fabrication method allows researchers to create complex, customized soft robotic structures with unprecedented precision and efficiency.

Traditional fabrication methods for soft robotics often involve manual assembly or molding techniques, which can be time-consuming and limit design flexibility. However, 3D printing enables precise, layer-by-layer fabrication of intricate soft robotic structures with minimal post-processing required. This allows researchers and engineers to quickly iterate designs and produce prototypes with high fidelity, accelerating the development cycle of soft robotic systems.

Functional soft materials are particularly well suited for soft robotics due to a wide range of stimulants and sensitive demonstration of large deformations, high motion complexities and varied multi-functionalities.

Moreover, advancements in 3D printing technology, such as improved resolution and material compatibility, have further enhanced the quality of printed soft robotics components, enabling them to exhibit complex functionalities and mechanical behaviors.

Printing Multiple Materials:

One of the most significant advantages of 3D printing for soft robotics is its capability to print multiple materials simultaneously. Unlike traditional manufacturing methods, which often require assembly of different components, 3D printing allows for the seamless integration of various materials within a single print. This capability opens up a wide range of possibilities for designing soft robots with heterogeneous properties, such as varying stiffness, elasticity, and conductivity. By strategically combining different materials during the printing process, researchers can create multi-functional soft robotic structures capable of performing complex tasks, such as gripping, locomotion, and sensing, with unprecedented efficiency and versatility.

Recent Advancements

Recent advancements in 3D printing technology have further propelled the field of soft robotics forward. Researchers have developed novel printing techniques and materials specifically tailored for soft robotic applications, such as silicones with high stretchability and biocompatibility. These materials exhibit unique mechanical properties that are well-suited for soft actuators and sensors, enabling robots to perform complex movements and interact safely with humans. Moreover, researchers have successfully integrated soft robotics with other emerging technologies, such as artificial intelligence and stretchable electronics, paving the way for the development of intelligent, self-aware soft robots capable of sensing and adapting to their environment in real-time.

Applications and Impact:

The integration of 3D printing technology into the field of soft robotics has led to significant advancements in both research and practical applications. Researchers are exploring novel designs and functionalities for soft robots, ranging from biomedical devices for minimally invasive surgery to wearable exoskeletons for rehabilitation and assistance.

The potential applications of soft robotics are vast and diverse, spanning from exploration and defense to healthcare and beyond. For example, NASA is exploring the use of soft, tentacled robots for underwater exploration on distant moons, while the military is investing in soft robots for stealthy maneuvering and surveillance missions.

In 2016, team of researchers at Case Western Reserve University created a robot made from the muscle of a sea slug in a flexible 3D-printed polymer body. Robots such as these could be used in surveillance and search missions in the ocean.

US military researchers, in collaboration with the University of Minnesota (UMN), have developed an advanced 3D printer named the “Solider,” specifically designed for creating soft robots. Dr. Ed Habtour from the Army Research Laboratory highlights the importance of structural flexibility and adaptability for stealthy maneuvers in confined spaces, emphasizing the printer’s capability to generate soft actuators and robots on demand. This technology, developed by Prof. Michael McAlpine’s team at UMN, draws inspiration from invertebrates, focusing on emulating their soft distributed actuation circuitries to achieve high bending motions without skeletal support.

Additionally, investigators at the Army’s Institute for Soldier Nanotechnologies (ISN), based at MIT, have developed a 3D printing platform for designing magnetically actuated devices. By infusing magnetic particles into printable ink, this technology enables the creation of flexible materials for integration into Soldier systems. Dr. Aura Gimm highlights the potential of this research in creating shape-morphing structures using auxetic metamaterials, which shrink in both longitudinal and transverse directions when exposed to external magnetic actuation. Army Research Laboratory’s Dr. Alex Hsieh underscores the significance of soft robots for maneuvering on complex battlefield terrains, citing their dexterity compared to rigid robots. This approach allows for the modeling and design of magnetically controlled device sections, enabling complex soft robotic tasks essential for military applications.

Harvard engineers have developed one of the first 3D-printed soft robots capable of autonomous movement, addressing a longstanding challenge in soft robotics: integrating rigid and soft materials seamlessly. The robot consists of a soft plunger-like body with pneumatic legs and a rigid core module containing power and control components, integrated through a gradient of material properties to eliminate failure points. Combustion powers the robot’s movement, as it inflates its legs with a mixture of butane and oxygen, enabling powerful jumps reaching up to six times its body height vertically and half its body width laterally, making it effective for navigating obstacles and harsh environments.

Nicholas Bartlett, the study’s lead author, highlights the robot’s ability to withstand impacts and survive combustion events, resulting in improved overall robustness and quicker locomotion compared to traditional soft robots. This resilience and mobility make it suitable for various applications, particularly in unpredictable environments or disaster scenarios where surviving falls and unexpected developments are crucial. Meanwhile, researchers at the University of Minnesota have developed a groundbreaking process for 3D printing stretchable electronic sensory devices, potentially granting robots the ability to sense their surroundings. This technology, which involves printing specialized “inks” with a multifunctional printer, offers vast possibilities, ranging from health monitoring to chemical sensing and energy harvesting.

In the healthcare sector, soft robots hold promise for minimally invasive surgery, prosthetics, and rehabilitation devices. As researchers continue to push the boundaries of soft robotics with innovative technologies like 3D printing, we can expect to see increasingly sophisticated and versatile robots that revolutionize how we interact with the world around us.

The ability to rapidly prototype and iterate designs using 3D printing has also democratized access to soft robotics, allowing enthusiasts and hobbyists to experiment with creating their own custom robotic systems. Furthermore, as 3D printing technology continues to evolve and become more accessible, the potential for innovation in soft robotics is limitless, paving the way for the development of next-generation robotic systems with unprecedented capabilities and applications.

3D printing Robotic Hand

For the first time, researchers have achieved a significant milestone in the field of robotics by successfully printing a robotic hand with bones, ligaments, and tendons made of different polymers in a single process. This breakthrough was made possible by a new technology developed by researchers at ETH Zurich and a US-based startup, Inkbit. By making 3D printing compatible with slow-curing polymers, this innovative approach has greatly expanded the capabilities of soft robotics, offering enhanced elastic properties and increased durability compared to previous materials.

The key advancement lies in the ability to combine soft, elastic, and rigid materials seamlessly, allowing for the creation of complex and durable robots with a wide range of functionalities. Utilizing slow-curing polymers such as thiolene, researchers can now produce intricate structures that return to their original state rapidly after deformation, making them ideal for applications in soft robotics. This flexibility in material selection enables the fabrication of delicate robotic components, including bones, ligaments, and tendons, in a single printing process.

The new technology incorporates a 3D laser scanner and a feedback mechanism, which allows for real-time monitoring and adjustment of each printed layer to compensate for surface irregularities. Unlike traditional methods that require scraping off irregularities after each curing step, this approach ensures precision and accuracy without compromising the quality of the final product. Inkbit, the MIT spin-off responsible for developing the printing technology, plans to offer 3D printing services to customers and commercialize the new printers. Meanwhile, researchers at ETH Zurich aim to explore further possibilities and develop more sophisticated robotic structures and applications using this groundbreaking technology.

Conclusion:

In conclusion, 3D printing has emerged as a key fabrication technology for soft robotics, offering unparalleled advantages in terms of high-quality fabrication and the ability to print multiple materials simultaneously. By leveraging the capabilities of 3D printing, researchers and engineers are pushing the boundaries of what is possible in soft robotics, creating innovative solutions for a wide range of applications. As the field continues to evolve, 3D printing will undoubtedly play a central role in shaping the future of soft robotics, driving innovation and unlocking new opportunities for robotic systems with advanced functionalities and capabilities.