Learning Materials

Curriculum

We put together this curriculum for graduate students that intend to do research in the development and implementation of hybrid simulation methods. We suggest you take advantage of these educational resources to build your toolbox

Demo Codes:

A Real-Time Hybrid Simulation (RTHS) Demo code
It includes MATLAB codes and Simulink models of an RTHS simulation example designed to help beginners to understand the concept of RTHS and its representation.

Virtual RTHS Sample Using xPC
It provides MATLAB codes and Simulink models to perform a virtual real-time hybrid simulation of a two-story structure with a damper at the first story subjected to an earthquake using two xPC target computers.

A Real-Time Hybrid Simulation Demo Code for a Structure with Base Isolation
It describes the set-up of a simple RTHS simulation with base isolation applied to a single story steel structure. It is accompanied by MATLAB codes and Simulink models with the purpose of helping beginners understand the RTHS concept and the effects of isolation on the response of the structure.

Educational Video Series

PID control
This video provides information on PID control algorithm in control systems.

Hydraulic actuators and RTHS
This video discusses background information on hydraulic actuators and their use in RTHS for structural engineering applications.

Advanced Topics in Real-time Hybrid Simulation 201: Webinar Series

Hybrid Simulation of Wind-Assisted Ships
The focus of this presentation is the wind-assisted propulsion of large cargo ships. Wind-assisted propulsion is a promising way to reduce emissions in the maritime sector. Many competing sail technologies and products already exist, however, there is still a lack of methods to properly quantify their overall performance. This webinar will present the first hybrid simulations of a bulk carrier fitted with four rotor sails (also known as Flettner rotors). The tests were conducted in NTNU/SINTEF's towing tank in 2021. Wind loads were modeled numerically, as is done for floating wind turbines, and applied in real-time on the ship, which acted as the physical substructure, using a cable-driven robot. In this talk, we will discuss the experimental setup, show the ship's performance under sails, and discuss the challenges that are currently being addressed to improve these methods.

Real-time and Stochastic Hybrid Simulation
In current practice, substructures and excitation that characterize a hybrid model are often considered to be deterministic. However, nominally identical specimens are, in practice, never actually identical, while excitation is usually stochastic. Therefore, there is an increased necessity to understand how uncertain structural systems perform under uncertain operating conditions. To conduct stochastic hybrid simulations, an uncertainty quantification framework was employed in this investigation. It is based on the design of probabilistic hybrid models, uncertainty propagation as well as surrogate modeling, and global sensitivity analysis. Global sensitivity analysis utilizing Sobol' indices is performed to investigate the sensitivity of the simulation results to certain input parameters, uncovering the inner workings of the hybrid model in both epistemic and aleatory sense. The major contribution of this investigation is a high-fidelity simulation tool that can be used to apply uncertainty quantification techniques to examine the dynamic response of uncertain systems operating under uncertain conditions, with the overreaching goal of dynamic validation and calibration of models used in engineering design.

Advances in Multi-axial Real-time Hybrid Simulation
In this talk, we examine multi-actuator techniques to conduct multi-axial RTHS (or maRTHS), focusing on revealing the latest breakthroughs and current challenges. In particular, we explain the framework for three-dimensional testing, including advanced topics in multi-input, multi-output (MIMO) modeling of dynamic systems, multi-actuator control, nonlinear kinematics, and force measurements. Finally, two maRTHS experiments will be presented using centralized and decentralized multivariate control approaches for dynamic compensation.

Developing Real-time Hybrid Simulation for Wave-Structure Interaction
This presentation outlines the ongoing development and implementation of real-time hybrid simulations (RTHS) for wave-structure interaction applications, termed hydro-RTHS, at the NHERI-EF Large Wave Flume and Multi-directional Wave Basin at Oregon State University (OSU). This hydro-RTHS framework couples physical wave loading with computational structural models. Parameters difficult to model physically in wave experiments are modeled numerically, virtually extending OSU’s experimental capabilities. This approach is practical as it physically simulates the wave-structure response. Similarly, additional degrees-of-freedom, material nonlinearities, and similitude advantages can be gained through the coupled numerical model. The hybrid physical-numerical simulation then represents the response of a much larger and more complex system than could otherwise be tested. This presentation will describe the development and implementation of hydro-RTHS, including: (1) difficulties in conducting RTHS in a submersed, wet testing environment, (2) extension of methods well-established in earthquake engineering to wave-structure interaction, and (3) ongoing hydro-RTHS projects at OSU.

Hybrid Simulation 101: Webinar Series

Developing Real-time Hybrid Simulation for Wave-Structure Interaction
This webinar provides an overview of the hybrid simulation data model in DesignSafe and presents an example application of data curation and publication. The main components of the data model include Master Simulation Coordinator, Simulation Substructure, and Experimental Substructure with each of these components generating data during a hybrid simulation. An example of published test data from real-time hybrid simlations with a shake table experimental substructure is presented.

Anatomy of a Hybrid Simulation / Real-Time Hybrid Simulation

This webinar provides an introduction to the range of methods in this class of experimental techniques, the essential components needed to perform a hybrid simulation, a few recent experiments performed using this method, and a readily available sample code / learning tool is available.

Pseudo-Dynamic Hybrid Simulation
This webinar presents the pseudo-dynamic hybrid simulation methods, which is typically conducted at an extended time scale. The focus of this presentation will be on the overview of the pseudo-dynamic (PsD) hybrid simulations, required components, to run PsD hybrid simulations, commonly used test configurations for executing PsD hybrid simulation, followed by a few example experimental implementations.

Designing a Successful Real-Time Hybrid Simulation
This webinar explains the steps to take for choosing the partitioning to use in RTHS, a fundamental step towards successful RTHS implementation. As a case study, this methodology will be demonstrated using the recent Benchmark control problem for real-time hybrid simulation which has been recently presented to the RTHS community to enable community-wide examination to compare and contrast various methods for the design of a robust RTHS controller.

Technical Talks and Presentations

Past Workshops