Sökning: "Constraint stabilization"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Constraint stabilization.

1. 1. Ghosts and machines : regularized variational methods for interactive simulations of multibodies with dry frictional contacts

   Författare :Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; Computational physics; Beräkningsfysik;

   Sammanfattning : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. LÄS MER

3. 2. On design of low order H-infinity controllers

   Författare :Daniel Ankelhed; Anders Hansson; Anders Helmersson; Jakob Stoustrup; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; H-infinity synthesis; linear systems; linear matrix inequalities; rank constraints; optimization; rational constraints; interior point methods; Automatic control; Reglerteknik;

   Sammanfattning : When designing controllers with robust performance and stabilization requirements, H-infinity synthesis is a common tool to use. These controllers are often obtained by solving mathematical optimization problems. The controllers that result from these algorithms are typically of very high order, which complicates implementation. LÄS MER

4. 3. High-order finite element methods for incompressible variable density flow

   Författare :Lukas Lundgren; Murtazo Nazarov; Anders Logg; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Finite element method; artificial viscosity; Navier-Stokes equations; conservation properties; artificial compressibility; viscous regularization; variable density flow; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Sammanfattning : The simulation of fluid flow is a challenging and important problem in science and engineering. This thesis primarily focuses on developing finite element methods for simulating subsonic two-phase flows with varying densities, described by the variable density incompressible Navier-Stokes equations. LÄS MER

5. 4. Correctness and Safety in Planning and Control via State-Space Partitions and Barrier Functions

   Författare :Xiao Tan; Dimos V. Dimarogonas; Samuel Coogan; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dynamical systems; Control barrier functions; Optimeringslära och systemteori; Optimization and Systems Theory;

   Sammanfattning : Autonomous systems have become increasingly prevalent in various industries, ranging from household cleaning robots to line inspection drones and copilot vehicles. Ensuring real-time safety is becoming a critical issue when the environment is rapidly changing. LÄS MER

7. 5. Nonlinear Model Predictive Control for Autonomous Vehicles

   Författare :Paolo Falcone; Universita degli Studi del Sannio; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : In this thesis we consider the problem of designing and implementing Model Predictive Controllers (MPC) for stabilizing the dynamics of an autonomous ground vehicle. For such a class of systems, the non-linear dynamics and the fast sampling time limit the real-time implementation of MPC algorithms to local and linear operating regions. LÄS MER