Advanced Intelligent Systems recently published an article titled “Development of Flexure‐Based Supernumerary Robotic Finger for Hand Function Augmentation,” detailing a novel approach to improving robotic finger designs. This innovative flexure-based supernumerary robotic finger (FBSF) aims to address existing limitations by mirroring human thumb proportions and utilizing electromyographic signals for actuation. The study highlights how the FBSF extends the workspace and enhances functionality, potentially transforming assistive technologies. Additionally, the study underscores the importance of user-driven control mechanisms in advancing robotic finger applications.
Enhanced Workspace and Design
The newly introduced FBSF aims to extend the functional capabilities of the human hand by approximately 29.72%. To achieve this, the design replicates the proportions and movements of the human thumb, which, according to finite element analysis, offers the largest workspace and bending angle. Moreover, the incorporation of polycarbonate paired crossed flexural hinge structures and high impact polystyrene links contributes to its efficient performance while maintaining lightweight properties. The main body of the FBSF weighs 59 grams, and the control box weighs 170 grams, making it a practical addition to the user’s hand.
The control mechanisms are crucial for the effective use of the FBSF. By utilizing the electromyographic signal of the extensor carpi ulnaris via isometric contractions, the FBSF allows for user-driven control and decoupled actuation. This ensures that the device responds accurately to the user’s intentions, facilitating seamless cooperation between the robotic finger and the human hand. An experimental protocol involving tasks such as releasing and clenching demonstrated the FBSF’s responsiveness and efficiency in task execution.
Performance and Application
Performance tests have showcased the FBSF’s ability to grasp various objects, with a verified maximum payload of 2.6 kilograms. The motion capture camera system confirmed the extension of the hand workspace, indicating the practical benefits of this development for real-world applications. Such capabilities suggest that the FBSF can significantly aid in tasks requiring precision and strength, potentially offering substantial assistance in both everyday activities and specialized tasks.
Previous research in the field of robotic fingers has often encountered challenges in achieving a balance between functionality, control, and user comfort. Earlier designs frequently suffered from limited flexibility and cumbersome control mechanisms. However, the flexure-based approach of the FBSF represents an advancement in addressing these issues by offering improved ergonomics and responsiveness. Comparatively, this development marks a notable step forward from prior models, which often lacked the refined user-driven control seen in the FBSF.
Similar innovations in the past have focused on enhancing the mechanical strength and range of motion of robotic fingers. However, many such solutions did not fully integrate the user’s intent into the control system, leading to less intuitive usage. The FBSF, with its electromyographic signal-based control, bridges this gap by ensuring that the device moves in harmony with the user’s natural hand movements, thus providing a more seamless and intuitive experience.
Overall, the development of the FBSF offers valuable insights into the future of assistive robotic technologies. By effectively expanding the workspace and enhancing the control mechanisms, the FBSF can potentially revolutionize various applications, from aiding individuals with impaired hand functions to enhancing the capabilities of healthy users. The use of advanced materials and precise actuation signals aligns with the growing trend of creating more user-centric assistive devices. This development, therefore, not only contributes to the field of robotics but also opens new avenues for enhancing human-machine interaction.
