Gears and hands

Hopsan is an open-source multi-domain system simulation tool developed at the division of Fluid and Mechatronic Systems at Linköping University. Hopsan is developed by a group of coworkers at the division, all with varying levels of knowledge in programming, modeling, simulation and hydraulics.

Development first began in the late 1970’s, and it has played an important role in education and research projects and over time.

In 2009, development began of a new object-oriented simulation platform written in C++. There is a strong focus on multi-core support and tool interoperability. This version is available under the GPL open source license.

Hopsan was the first system simulation tool with built-in support for multi-core simulation. It is also the only simulation software that is built around the transmission line modelling (TLM) technique (or bi-directional delay lines). With this method, models can be automatically partitioned by introducing physically motivated time delays between components. Each part of the model can then be solved independently during each time step. This improves simulation performance, numerical robustness and model scalability makes the simulation very robust and fast, and provides a natural mechanism for parallel simulation.

Feautures include

  • Multi-core support for faster simulations
  • Model export/import using Functional Mock-Up Interface (FMI)
  • Model export to Matlab/Simulink
  • Plot data export to CSV, XML, Gnuplot & Matlab
  • Creating models from Modelica and C++
  • Interactive & replay animations
  • Numerical optimization
  • Sensitivity analysis
  • Frequency-domain analysis
  • Energy losses calculations
  • Scripting using HCOM or Python

The transmission-line modelling

Contact persons


Publications and conference proceedings related to Hopsan project.

Tool-Independent Distributed Simulations Using Transmission Line Elements And The Functional Mock-up Interface
Author: Robert Braun and Petter Krus
Published: 54thSIMS Conference (SIMS 2013), Bergen, 2013

Aircraft System Simulation for Preliminary Design
Author: Petter Krus, Robert Braun, Peter Nordin, Björn Eriksson
Published: 28th Congress of the International Council of the Aeronautical Sciences, 23 - 28 September 2012, Brisbane, Australia. Paper ICAS 2012-1.9.3

Towards A Parallel Distributed Equation-Based Simulation Environment
Author: Robert Braun and Petter Krus
Published: 53rd SIMS Conference on Simulation and Modelling (SIMS 2012), Reykjavik, 2012

Multi-Threaded Real-Time Simulations of Fluid Power Systems
Author: Robert Braun and Petter Krus
Published: 8th International Fluid Power Conference (8IFK), Dresden, 2012

High Performance System Simulation Using Multiple Processor Cores
Author: Robert Braun, Peter Nordin, Björn Eriksson and Petter Krus
Published: The Twelfth Scandinavian International Conference on Fluid Power (SICFP), Tampere, 2011

Towards Efficient Distributed Simulation in Modelica using Transmission Line Modeling
Author: Martin Sjölund, Robert Braun, Peter Fritszon and Petter Krus
Published: 3rd International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools (EOOLT), Oslo, 2010

Hopsan NG, A C++ Implementation using the TLM Simulation Technique
Author: Björn Eriksson, Peter Nordin and Petter Krus
Published: The 51st Conference on Simulation and Modelling (SIMS), Oulu, 2010

Next Generation Simulation Software using Transmission Line Elements
Author: Mikael Axin, Robert Braun, Alessandro Dell'Amico, Björn Eriksson, Peter Nordin, Karl Pettersson, Ingo Staack and Petter Krus
Published: Fluid Power and Motion Control (FPMC), Bath, 2010

Read more about our research

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Department of Management and Engineering