DYMARA – A dynamic manikin with fiber-based modeling of skeletal muscles

This project aims at the development of a fiber-based modeling approach for the behavior of muscles within the musculoskeletal system. Supported by the German Federal Ministry of Education and Research, three departments of the Fraunhofer ITWM Kaiserslautern, TU Kaiserslautern and FAU Erlangen join forces in this project, along with the industrial partners fleXstructures GmbH and MaRhyThe Systems GmbH & Co. KG.

The long term goal is a digital human model that can be used for making workplaces more ergonomic and for improving the health of workers in an industrial environment. Also, therapy planning and prosthesis development are a focus.


The core idea is to describe the skeletal system as a rigid multibody system which is actuated by muscles. Each muscle is represented by a system of one-dimensional cables with variable cross section that undergo large deformation and strains. We employ a incompressible Kelvin-Voigt material for the passive behavior and a active stress law.

Contact between the muscle fibres and the rigid bodies is taken into account by means of a finite element framework and the penalty method.
As first result, we have  applied our framework to conduct a forward simulation of a simple upper limb model. The figure shows a snapshot of this simulation with the biceps and triceps muscles.


For more information contact Bernd Simeon (simeon@mathematik.uni-kl.de).