Effortlessly performing activities of daily living constitutes a cornerstone of our personal independence. Naturally, various forms of upper limb impairments can have a substantial impact on quality of life. We developed the Myoshirt, a textile-based soft wearable robot, or exomuscle, that autonomously follows the user’s movements and thereby assists the shoulder against gravity. With the Myoshirt, participants without impairments (n = 10, 5 male) experienced a delayed onset of muscular fatigue by 51.1 s (36.1%, P < 0.001), while during a functional task their muscular activity decreased by 49.1% (P < 0.001). Analogously, two participants with upper limb impairments due to a muscular dystrophy and a spinal cord injury experienced a delayed onset of muscular fatigue during unloaded arm lifts by 256.4 s (61.5%) and by 450.6 s (210.3%), respectively. Our evidence suggests that the Myoshirt is an effective tool that intuitively assists the shoulder during functional reaching tasks, with the potential of increasing the personal independence of people with upper limb impairments.
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We thank J. Song and D. Hollinger for their valuable contributions during the development and evaluation of the Myoshirt, and furthermore the students and research staff at the Sensory–Motor Systems Lab for their contributions and helpful feedback: F. Haufe, S. Brendle, F. Teuscher, D. Ozan and M. Macuglia. Finally, we would like to thank our participants for their time and insightful feedback. This work was supported by the Swiss National Center of Competence in Research (NCCR) Robotics, Swiss National Science Foundation 51_NF_40_185543, received by R.R.
The authors declare no competing interests.
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Georgarakis, AM., Xiloyannis, M., Wolf, P. et al. A textile exomuscle that assists the shoulder during functional movements for everyday life. Nat Mach Intell 4, 574–582 (2022). https://doi.org/10.1038/s42256-022-00495-3