Jan Tomec

ESR 9:
Jan Tomec

joined the THREAD project in April 2020 (read his welcome message)

My name is Jan Tomec. I am 24 years old and I have just finished my master’s degree in mechanical engineering at the University of Ljubljana. This is also where I finished my bachelor’s degree before that and my high school before that and basically where I lived for the last 10 years. Such monotonous style of life conflicted with my adventurous spirit. The mentor for my internship suggested to me the project THREAD and I was hooked immediately.

For a couple of years now I was working as an intern on different industrial projects which involved mechanics, mathematics and coding. Projects included numerical simulations of nonlinear three-dimensional shell structures, fluid dynamics around rigid bodies, optimisation of production lines and so on. During my studies I took a special interest in continuum mechanics, dynamics, numerical computations and coding.

Considering my background I find the topic on beam theory fascinating. I believe this program will enhance my expertise in the field of mechanics and programming, but also give me a lot of personal experiences. This will give me the edge in the future when I would like to work on similarly engaging projects in industry.

Jan Tomec, April 2020

Host Institution
University of Rijeka, Faculty of Civil Engineering (Croatia)


The ESR will work on mechanical analysis of satellite aerials during the rocket-launch phase, when they are exposed to extreme inertial loading and high-frequency vibration and impacts in a compact confinement within a rocket. The design requirement is that the satellite should occupy as little space within the rocket as possible, yet still be able to allow the aerials to deploy without permanent deformation or damage upon satellite ejection from the rocket into the orbit. The simulation will be performed using 1D Cosserat continuum (geometrically exact beam theory) and non-linear finite-element analysis in both statics and dynamics within which various interpolation options will be investigated for accuracy and robustness. In addition, a number of time-stepping schemes will be devised, which shall respect geometry of the problem configuration space and preserve mechanical constants of motion. The work will be supported by an industrial partner in space technologies.

Expected Results

The project is expected to result in higher-order spatial interpolation of displacements and rotations parametrised to provide objective solutions on the non-linear problem manifold. Conservative time-integration techniques devised on different non-linear manifolds will be assessed and generalised to account for unilateral constraints. A test rig will be designed and employed to provide experimental validation.


planned at Space SI (industrial partner), University of Innsbruck and University of Liège

associated with the Industrial Challenges

IC 5 Aerospace engineering
IC 9 Software development


Articles in peer-reviewed scientific journals

  • Jan Tomec, Gordan Jelenić (2023): Momentum and near-energy conserving / decaying time integrator for beams with higher-order interpolation on SE(3); Computer Methods in Applied Mechanics and Engineering 419, 116665; DOI: 10.1016/j.cma.2023.116665, see also link
  • Jan Tomec, Gordan Jelenić (2024): Frictionless line-to-line contact: comparison of mortar and unbiased formulation in combination with Lagrange-multiplier and penalty method; International Journal of Solids and Structures 286–287, 112586; DOI: 10.1016/j.ijsolstr.2023.112586, see also link
  • Jan Tomec, Gordan Jelenić (2022): Analysis of static frictionless beam-to-beam contact using mortar method; Multibody System Dynamics 55, 293–322; DOI: 10.1007/s11044-022-09823-2, see also link

Publications in conference proceedings

  • Jan Tomec, Gordan Jelenić (2021): Geometrijski točni 3D gredni element: SE(3) formulacija (Eng.: Geometrically exact 3D beam element: SE(3) formulation). In: Marino Brčić, Ante Skoblar, Dragan Ribarić (eds.): Proceedings of the 11th Meeting of the Croatian Society of Mechanics / Rijeka, Croatia: Croatian Society of Mechanics, 2021, pp. 293–297; link
  • Jan Tomec, Gordan Jelenić (2020): Statička analiza geometrijski točnim 3D grednim elementom (Eng.: Static analysis with geometrically exact 3D element). In: Darko Damjanović, Dražan Kozak, Pejo Konjatić, Marko Katinić (eds.): Proceedings of the 10th Meeting of the Croatian Society of Mechanics / Slavonski Brod, Croatia: Croatian Society of Mechanics, 2020, pp. 271–276; link