Advanced Intelligent Systems published an article titled “Untethered Fluidic Engine for High‐Force Soft Wearable Robots,” detailing an innovative solution in the realm of soft wearable robotics. This article highlights the development of an electrohydraulic actuation system that integrates portability and high-force capabilities, addressing significant limitations observed in current fluid-driven systems. Crucially, this novel design is lightweight, making it conducive for daily human assistance applications.
Design and Implementation
Fluid-driven artificial muscles, mimicking the behavior of biological muscles, have garnered attention for their potential in wearable assistive robots. However, existing technologies frequently encounter issues such as the necessity for tethered pressure sources or bulky configurations due to flow control valves. These limitations impede the performance and practicality of soft wearable robots.
The newly developed electrohydraulic actuation system tackles these challenges through a two-pronged design approach. Initially, a direct-drive actuation paradigm is introduced, comprising a motor, gear-pump, and hydraulic artificial muscle (HAM), resulting in a compact and valveless setup that weighs only 1.6 kg. Furthermore, a fluidic engine driven by a high-torque motor and a custom-designed gear pump is incorporated, capable of generating pressures up to 0.75 MPa. This setup enables the HAM to produce high forces of up to 580 N.
Performance and Applications
Experimental evaluations indicate that this fluidic engine substantially outperforms existing systems concerning mechanical efficiency. The high-pressure capability and untethered operation of the system suggest significant potential for its application in soft wearable robots designed to assist humans in everyday tasks. The compact and lightweight nature of the system also enhances its suitability for wearable applications.
Earlier research in the field of fluid-driven soft wearable robots predominantly focused on tethered systems, which were limited by their dependency on external power sources. These systems, while capable of generating high forces, lacked the portability required for practical daily use. Additionally, untethered systems developed in the past were often constrained in their force output, rendering them less effective for real-world applications.
In comparison, the current electrohydraulic system bridges the gap by offering both high-force capabilities and portability. The integration of a direct-drive actuation paradigm and a powerful fluidic engine sets it apart from previous technologies. The enhanced mechanical efficiency and compact design represent a significant step forward, potentially revolutionizing the deployment of soft wearable robots.
Looking ahead, this electrohydraulic system could pave the way for more widespread use of soft wearable robots in various fields, including healthcare and rehabilitation. The ability to provide substantial assistive forces without the need for bulky external equipment enhances mobility and usability for end-users. As the technology continues to evolve, it could lead to the development of more advanced and user-friendly wearable robotic systems.
This research addresses the critical limitations of existing fluid-driven soft wearable robots by introducing a compact and high-force electrohydraulic actuation system. The combination of portability and efficiency in this design marks a significant advancement in the field, potentially transforming the usage and effectiveness of wearable robots in assisting human activities.
