A personalized exosuit for real-world walking

Researchers have developed a new approach in which robotic exosuit assistance can be calibrated to an individual and adapt to a variety of real-world walking tasks in a matter of seconds. The bioinspired system uses ultrasound measurements of muscle dynamics to develop a personalized and activity-specific assistance profile for users of the exosuit.

Credit: Harvard John A. Paulson School of Engineering and Applied Sciences

People rarely walk at a constant speed and a single incline. We change speed when rushing to the next appointment, catching a crosswalk signal, or going for a casual stroll in the park. Slopes change all the time too, whether we’re going for a hike or up a ramp into a building. In addition to environmental variably, how we walk is influenced by sex, height, age, and muscle strength, and sometimes by neural or muscular disorders such as stroke or Parkinson’s Disease.

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new approach in which robotic exosuit assistance can be calibrated to an individual and adapt to a variety of real-world walking tasks in a matter of seconds. The bioinspired system uses ultrasound measurements of muscle dynamics to develop a personalized and activity-specific assistance profile for users of the exosuit.

The new system only needs a few seconds of walking, even one stride may be sufficient, to capture the muscle’s profile. For each of the ultrasound-generated profiles, the researchers measure how much metabolic energy the person uses during walking with and without the exosuit. The researchers found that the muscle-based assistance provided by the exosuit significantly reduced the metabolic energy of walking across a range of walking speeds and inclines. The exosuit also applied lower assistance force to achieve the same or improved metabolic energy benefit than previous published studies.

Source (Harvard John A. Paulson School of Engineering and Applied Sciences. “A personalized exosuit for real-world walking: Ultrasound measurements of muscle dynamics provide customized, activity-specific assistance.” ScienceDaily. ScienceDaily, 10 November 2021.)

Original paper: R. W. Nuckols, S. Lee, K. Swaminathan, D. Orzel, R. D. Howe, C. J. Walsh. Individualization of exosuit assistance based on measured muscle dynamics during versatile walkingScience Robotics, 2021; 6 (60) DOI: 10.1126/scirobotics.abj1362