Hoffmann, Ramona

Dr.-Ing.

Ramona Hoffmann

  • 2005 Dipl.-Ing. in Mechanical Engineering, University of Kaiserslautern
  • 2005 – 2008 Corporate Sector Research and Advanced Engineering, Applied Research Microsystem Technologies, Robert Bosch GmbH Stuttgart
  • 2008 – 2009 Production engineer in the international manufacturing network for Common Rail Injector CV, Robert Bosch GmbH Homburg
  • 2009 – 2011 Doctoral candidate, Computational Dynamics and Control, University of Kaiserslautern
  • 2011 – 2013 Doctoral candidate, Chair of Applied Dynamics, Friedrich-Alexander-Universität Erlangen-Nürnberg
  • 2014 Dr.-Ing. Friedrich-Alexander-Universität Erlangen-Nürnberg
  • 2013 – 2015 Scientific employee, Fraunhofer ITWM, Kaiserslautern
  • 2015 – 2016 Scientific employee, Institute of Applied Dynamics, Friedrich-Alexander-Universität Erlangen-Nürnberg

theses

 

reviewed journal publications

2019

2013

2011

conferences and proceedings

2016

2013

2012

2011

 

further publications

 

  • Simulation and optimal control of the dynamics of multibody systems in biomechanics and robotics

    (Third Party Funds Single)

    Term: 2008-12-01 - 2011-12-01
    Funding source: DFG-Einzelförderung / Emmy-Noether-Programm (EIN-ENP)

    Simulation is of great importance when studying everyday or athletic motions with regard to improvements in ergonomics and performance. In particular for medical problems like analysing gait or optimising prostheses as well as for planning robot manoeuvres, simulation is often the only way to estimate the actuating and applied forces and torques. An approximate solution can only be as accurate as the underlying numerical method represents the system’s characteristic properties. If, for example, the energy required to perform a motion is a criterion of interest, the use of an energy consistent method is crucial. In purely forward dynamical simulations, here mechanical integrators are widely accepted. This project aims to develop and investigate new efficient and robust methods for the dynamic optimisation of movements that guarantee the inheritance of the real solution’s relevant properties by the approximated solution. The developed methods are applied to varying fields. Multirate integrators are developed that simulate different system parts with individual time steps saving computational time while accuracy remains unchanged. To realistically simulate motions of the human arm, Hill-type muscle models actuate the limbs. A semi-analytic algorithm approximating the muscle path allows its use in optimal control problems with physiologically motivated cost functions. Everyday motions like operating a steering wheel or lifting a weight, as well as sports motions like long throw and shot put, are optimised. Another main point is the simulation of the lower extremities. The modelled limbs are actuated by joint torques and contact problems where inelasticities and friction are taken into account. Monopedal jumping and human gait are investigated. Changing between open and closed kinematic loops (double stance phase versus swing phase) is described by different holonomic constraints that are active or passive in different phases. For the example of optimising a pole vault, the introduced method is applied to a flexible multibody system. It is shown that the developed methods are very effective and flexible and therefore a variety of problems can be investigated ranging from robotics over everyday human motion to athletics’ high performance motions.