Human-Exoskeleton Interaction Portrait

Human-robot physical interaction contains crucial information for optimizing user experience, enhancing robot performance, and objectively assessing user adaptation. This study introduces a new method to evaluate human-robot co-adaptation in lower limb exoskeletons by analyzing muscle activity and interaction torque as a two-dimensional random variable. We introduce the Interaction Portrait (IP), which visualizes this variable's distribution in polar coordinates. We applied this metric to compare a recent torque controller (HTC) based on kinematic state feedback and a novel feedforward controller (AMTC) with online learning, proposed herein, against a time-based controller (TBC) during treadmill walking at varying speeds. Compared to TBC, both HTC and AMTC significantly lower users' normalized oxygen uptake, suggesting enhanced user-exoskeleton coordination. IP analysis reveals this improvement stems from two distinct co-adaptation strategies, unidentifiable by traditional muscle activity or interaction torque analyses alone. HTC encourages users to yield control to the exoskeleton, decreasing muscular effort but increasing interaction torque, as the exoskeleton compensates for user dynamics. Conversely, AMTC promotes user engagement through increased muscular effort and reduced interaction torques, aligning it more closely with rehabilitation and gait training applications. IP phase evolution provides insight into each user's interaction strategy development, showcasing IP analysis's potential in comparing and designing novel controllers to optimize human-robot interaction in wearable robots

Academic greenspace and well-being – Can campus landscape be therapeutic?: Evidence from a German university

This paper aims to provide a deeper understanding of green spaces as health-promoting campus environments. Our study of a campus green space at the University of Bonn, Germany, is one of the first attempts to quantify health-promoting effects of Academic Greenspace among students, adding to our understanding of how green spaces can serve as everyday therapeutic landscapes. We take a closer look at the interlinkages between students’ perceptions of their health and physical, social and mental well-being in place and academic space. We focus on identity-creating elements, personal experiences, emotional bonding, subjective symbolic meanings, and social interaction. Based on our study results, a Healthy Academic Greenspace Framework (HAGF) was developed to reveal the processes by which Academic Greenspace becomes an important health resource on campus for many students. As a facilitator for recreation and attention restoration, as a place of identity as well as a place of social encounter and exchange, Academic Greenspace is meaningful as a place for experiencing everyday life with the potential to support healthy campus planning