Geometric and Algebraic Modeling
Date & Time: Tuesday, September 29, 2026 | 17:00 - 18:40
Place: Campus South, Mathematics Building 20.30 [Englerstraße 02], Room 2.059
Chairs: Edwin León-Cardenal
Abstract:
Confirmed Speakers
Speaker: Àlex Garcia-Herranz (Universitat Politècnica de Catalunya)
Title: Lie-Poisson Reduction and Stability of Kirchhoff Rods Under Gravity.
Abstract: Modeling heavy continuous elastic rods under gravity typically requires computationally intensive discretizations or simplifying approximations. This work addresses these limitations by developing a continuous mathematical model and a low-dimensional representation of Kirchhoff rods suitable for robotic control. While gravity breaks the classical left-invariance symmetry of the Hamiltonian on , we recover a reducible geometric structure by embedding the system into the semidirect product group . Lie-Poisson reduction then projects the system from the cotangent bundle to a low-dimensional dual Lie algebra.
We validate this framework by recovering the classical balance laws for internal forces and moments. Crucially for robotic applications, we prove that the mapping from the initial base wrench to the corresponding equilibrium rod configuration is a global diffeomorphism, establishing the six-dimensional base wrench space as a global control atlas.. Combined with a proof of path-connectedness for segmented stable configurations, this geometric formulation provides a foundation for global motion planning and safe manipulation of soft continuum robots and cables.
Speaker: Pablo Munarriz (Universidad de la Rioja)
Title: Polarization and depolarization of simplicial complexes
Abstract: In this talk, we show how the monomial operations of polarization and depolarization can be translated to abstract simplicial complexes. On the one hand, we describe the relation between the Koszul simplicial complex of a monomial ideal and that of its polarization.
On the other hand, we show that monomial depolarization can reduce a simplicial complex while preserving its homology. Using this idea, we propose an algorithm to efficiently compute the Alexander dual of abstract simplicial complexes.
Speaker: Abhilash Nayak (Universitat Politècnica de Catalunya)
Title: Geometric Modeling of Kinematic Grasp Constraints for Robotic Cloth Folding
Abstract: Robotic cloth folding requires coupling the rigid motion of a gripper with the deformation of a flexible surface. We present a lightweight geometric interface in which the gripper is modeled by a pose, a jaw state, and an attached grasping volume, represented as a box or a square pyramid in the gripper frame. When the gripper closes, cloth vertices inside this volume are selected, stored in local coordinates, and transported by quaternion-based rigid transformations. The resulting constraints are integrated into an inextensible cloth simulator and tested on a Franka robot arm by performing a corner-folding motion, highlighting the role of grasp support and gripper orientation.