Crewed missions to Moon and Mars are foreseen for the coming decades, posing new challenges for human movement science, particularly regarding space suit design, mobility, and motor control in different gravitational environments (Belobrajdic et al., 2021). The risk for operational errors and injuries in astronauts are increased by mental and physical fatigue (Mehta & Nuamah, 2021). We propose an integrative multisensory approach to conduct movement science in analog space missions by implementing digital twin models of environment and astronaut. Furthermore, a muscular fatigue simulation provides predictions on proposed tasks and traverses to optimize EVA operations based on astronaut’s capabilities. Two proof of concept studies were conducted based on the AMADEE-24 data.

Analog astronauts had to perform four generic geoscientific operations at different experiment sites approximately 50m apart at the beginning and the end of an EVA. All tasks and the ambulatory pathways were recorded using inertial motion capture (Xsens) to track the whole-body kinematics and EMG (Cometa) on eight muscles in the upper and lower body, additionally to the suit telemetry.

GPS and heart rate data of previous missions was used to develop individual physiological traverse models. An environmental model was constructed in Blender 4.1 based on the high-resolution drone images of the AMADEE-24 test site. A co-simulation of both models was performed to predict walking speeds and physiological responses during the traverses of six different EVAs of the AMADEE-24 mission (Fig.1). Predictions were compared to observed telemetry data.

In the second study, whole-body kinematics were investigated to detect the influence of fatigue on the astronaut’s gait pattern. Lateral trunk sway increased on average by 16% (7.55° to 8.75°) and log-scaled center of mass jerk almost tripled over the course of an EVA (-5.69 to -5.87) (Fig.2). A PCA of the lower-body kinematics revealed increased contribution of movement components associated with lateral stability work and trunk sway.

The findings are in line with current research on fatigue-induced gait alterations (Vieira et al., 2016; Mohr & Federolf, 2022). The novel aspect of our study is the detection of these adaptations in a complex, highly variable environment with many uncontrolled parameters.

Further developments focus on improving the functionality and validity of the digital twin models to enhance capabilities for movement analysis and predictions in crewed space missions.

Source: Benjamin Reimeir¹²⁶, Sara Maach¹, Amelie Leininger³, Selina Schindler⁴, Anna Wargel¹, Franziska Riedl¹, Tassilo Berghamer¹, Robert Weidner¹⁴, Gernot Grömer⁴, Peter Federolf², “Farside: Simulation System for Fatigue, Recovery And Physical Stress In Demanding Environments”, AMADEE-24 Science Workshop Booklet 2024

¹ Institute for Mechatronics, University of Innsbruck, Austria
² Department of Sport Science, University of Innsbruck, Austria
³ LMU Munich, Germany
⁴ Freie Universität Berlin, Germany
⁵ Laboratory of Manufacturing Technology, Helmut-Schmidt-University, Germany
⁶ Austrian Space Forum, Innsbruck, Austria