Design of an elastic drive train for integration into a robotic finger

Kurzfassung

Robotic hands are a highly versatile tool, particularly in human-centric environments. In these environments it is important to be able to handle objects designed for humans, thus becoming paramount for robotic hands to resemble human hands also in size. Moreover, the elasticity in both human and robotic hands allows for enhanced adaptability to the environment and robustness against unforeseen impacts. At present, we can distinguish two principal categories of high-functional robotic hands, in terms of the location of their actuation: those with remote actuation in conjunction with a flexible transmission, which are typically complex and challenging to maintain, and those with drive trains situated in the finger, which result in hands that are relatively large in comparison to human hands. In order to address this issue, the objective of this work is to examine the feasibility of integrating an elastic drive train into a robotic finger while maintaining a similar size to that of the human finger. Achieving this requires the combination of a motor, gearbox, and elastic element in a miniaturized form factor. The initial phase of the design process for this thesis involves the development of a concept that identifies potential options and evaluates their feasibility. Once an initial concept was selected for this work, in the next phase, we performed the required calculations, created models and conducted simulations in order to test the concept’s viability. This is followed by the construction of a prototype and an evaluation of its functionality. Even if the gearbox prototype can be further optimised to achieve the full potential of the drive train, the evaluation of the actuator demonstrates intrinsic elastic behaviour due to its elastic element. Furthermore, the overall size was reduced significantly.