Article: Vatsal, V; Hoffman, G; “Design and Analysis of a Wearable Robotic Forearm”, 2018 IEEE International Conference on Robotics and Automation (ICRA), 5489-5496
Abstract: This paper presents the design of a wearable robotic forearm for close-range human-robot collaboration. The robot’s function is to serve as a lightweight supernumerary third arm for shared workspace activities. We present a functional prototype resulting from an iterative design process including several user studies. An analysis of the robot’s kinematics shows an increase in reachable workspace by 246% compared to the natural human reach. The robot’s degrees of freedom and range of motion support a variety of usage scenarios with the robot as a collaborative tool, including self-handovers, fetching objects while the human’s hands are occupied, assisting human-human collaboration, and stabilizing an object. We analyze the bio-mechanical loads for these scenarios and find that the design is able to operate within human ergonomic wear limits. We then report on a pilot human-robot interaction study that indicates robot autonomy is more task-time efficient and preferred by users when compared to direct voice-control. These results suggest that the design presented here is a promising configuration for a lightweight wearable robotic augmentation device, and can serve as a basis for further research into human-wearable collaboration.
Funding Acknowledgement: National Science Foundation under NRI 
Funding Text: This material is based upon work supported by the National Science Foundation under NRI Award no. 1734399. We thank Siyu Zhou for assistance with the prototype’s physical design, and him and Harrison Chang for conducting the interaction pilot study.