Researchers from the Singapore University of Technology and Design (SUTD) have developed novel techniques, known as Automated Fibre Embedding (AFE), to produce complex fibre and silicone composite structures for soft robotics applications. Their work was published in IEEE Robotics and Automation Letters.
Many soft robot components, including sensors and actuators, utilise embedded continuous fibres within elastomeric substrates to achieve various functionalities. However, manual embedding of continuous fibres in soft substrates is challenging due to the complexities involved in handling precise layering, and retaining of the fibres in the patterned positions which are prone to inconsistencies.
In contrast, the AFE approaches developed by the research team led by Assistant Professor Pablo Valdivia y Alvarado, enabled high precision fabrication of complex layered composites without manual user intervention, thus significantly augmenting the range of fabrication possibilities while saving time and labour (refer to video).
The techniques exploited seamless combinations of fibre embedding with elastomeric deposition via Direct Ink Writing in an automated manner and allowed precise control of depth and fibre spacing within composite structures. This process automation has great potential for the fabrication and tailoring of soft robot components which require complex geometries that cannot be easily achieved manually.
In the study, three different approaches for automated layering and embedding of fibres inside silicone elastomers were discussed. To demonstrate the versatility of the techniques, several soft robotic applications ranging from inflatable actuators to inductive charging coils were also presented. Embedded fibre patterns enabled by the AFE fabrication processes were used to control colour change, tailor structural and morphological properties, activate thermal inputs, and enable electrical properties in soft robotic structures. Additionally, combinations of the AFE methods were demonstrated for the autonomous fabrication of several soft mechatronic components.
"Our work demonstrates the development of a family of fabrication processes that can be used to tailor complex fibre layouts within soft composites. This will pave the way for various novel applications in soft robotics including soft sensors and soft communication devices," said principal investigator, Assistant Professor Pablo Valdivia y Alvarado from SUTD.
IEEE Robotics and Automation Letters