HATon - Investigation of the upper body’s influence on the global dynamics of human walking

• Applicants: Privatdozent Dr.-Ing. Daniel Renjewski; Professor Dr. Syn Schmitt
• Subject Area: Automation, Mechatronics, Control Systems, Intelligent Technical Systems, Robotics ; Applied Mechanics, Statics and Dynamics ; Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 542210636

The HATon project aims to develop a deeper understanding of the mechanics and control of human gait, with particular consideration given to the dynamics and deformation of the upper body, consisting of the torso, arms, and head. Experimental setups are being developed to achieve this, including a treadmill with separate force measurement plates for the left and right sides and a safety and disturbance system to conduct suitable biomechanical experiments. Models will be derived from the collected data, explaining the observed dynamics and allowing for testing of control strategies. Both reductionist mechanical models will be developed to understand the basic principles of human gait and a complex neuro-musculoskeletal full-body model of humans for detailed computer simulations of walking. The former will be based on the current state of the literature. At the same time, the latter will be developed by synthesizing existing complex sub-models of the entire spine and lower extremities, including the pelvis. Both sub-models have been implemented in-house using high-level programming languages (C and C++).In addition to detailed model understanding from dynamic forward simulation, an inverse-dynamic model will be developed to analyze the local dynamics of the segments and joints of the entire human body in common interpreted script languages (Octave-Matlab-compatible). Based on the collected ground force measurements and kinematic marker data, this model will calculate the time courses of the cutting forces and moments (joint moments). These experimental raw and analyzed data will be used to validate the complex full-body model and verify any reductionist motion mechanics models. By introducing planned disturbances, mainly targeted body unloading interventions in the gait and the subjects' reactions to these disturbances, self-stabilizing mechanisms, as well as control circuits and concepts, can be inferred through the simulation calculations of the full-body model. This will provide deeper insights into the biomechanical design criteria of the musculoskeletal system, possible neural connections, and, thus, biological regulators. Local mechanical energy balances can also be determined, allowing conclusions to be drawn about functionally significant elasticities and energy dissipation, as well as metabolic calculations of individual muscles. The data, models, and software packages developed in the project will be made available to the scientific community for use and further development. In addition to basic biomechanical research, the expected findings of the project will benefit medical rehabilitation of patients with walking disorders caused by accidents or illness, as well as the technical development of walking assistance systems and humanoid robots.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Daniel J. Rixen