Abstract
Detailed prediction models with robust constraints and small sampling times in Model Predictive Control yield conservative behavior and large computational effort, especially for longer prediction horizons. Here, we extend and combine previous Model Predictive Control methods that account for prediction uncertainty and reduce computational complexity. The proposed method uses robust constraints on a detailed model for short-term predictions, while probabilistic constraints are employed on a simplified model with increased sampling time for long-term predictions. The underlying methods are introduced before presenting the proposed Model Predictive Control approach. The advantages of the proposed method are shown in a mobile robot simulation example.
Zusammenfassung
Detaillierte Prädiktionsmodelle mit robusten Nebenbedingungen in der Modellprädiktiven Regelung führen zu konservativem Verhalten und hohem Rechenaufwand, besonders für lange Prädiktionshorizonte. In dieser Arbeit werden die Vorteile bisheriger Arbeiten zur Modellprädiktiven Regelung erweitert und kombiniert, um Prädiktionsunsicherheit zu berücksichtigen und den Rechenaufwand zu reduzieren. Die vorgeschlagene Methode nutzt robuste Nebenbedingungen und ein detailliertes Modell für kurzfristige Prädiktionen, während probabilistische Nebenbedingungen, ein vereinfachtes Modell und eine größere Abtastzeit für die langfristige Prädiktion genutzt werden. Die Vorteile der neuen Methode werden in einem Simulationsbeispiel analysiert.
About the authors
Tim Brüdigam, M. Sc., is currently a research associate at the Chair of Automatic Control Engineering at the Technical University of Munich. His main research interest lies in advancing Model Predictive Control (MPC), especially stochastic MPC (SMPC), with possible application in automated driving.
Johannes Teutsch, B. Sc., is currently aiming for a Master’s degree in electrical and computer engineering at the Technical University of Munich, with focus on control and machine learning. His research at the Chair of Automatic Control Engineering revolves around Model Predictive Control (MPC).
Dirk Wollherr is Privatdozent at the Institute of Automatic Control Engineering, TU München. From 2001–2004 he was a research assistant at the Control Systems Group, TU Berlin. He was granted a research fellowship at the University of Tokyo in 2004. His research interests include autonomous mobile robots, and human-robot-interaction.
Marion Leibold is Privatdozent at the Institute of Automatic Control Engineering, TU München. From 2003–2004 she was a research assistant at the Control Systems Group, TU Berlin. Her research interests include optimal and nonlinear control in robotics applications.
Martin Buss has been a Full Professor (Chair) in the Chair of Automatic Control Engineering, Faculty of Electrical Engineering and Information Technology, Technical University of Munich since 2003. His research interests include automatic control, mechatronics, multimodal human system interfaces, optimization, nonlinear, and hybrid discrete-continuous systems.
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