OpenLSTO is an open-source software for level set based structural topology optimization, written in C++.

The topology optimization method deals with the problem of determining the optimal layout of material and connectivity inside a design domain in order to obtain the best structural performance. Level Set Method was originally developed as a mathematical tool for tracking the motion of interfaces. Its natural handling of topological changes coupled with a clear and smooth interface representation led to its use for structural topology optimization.

This first light version implements the M2DO lab’s level set topology optimization method to solve the problem of minimizing compliance (maximizing stiffness) under a volume constraint in a 2D design domain. It has been designed with ease of installation and use in mind. This means that, wherever possible, a conscious effort was made to develop in-house code components rather than relying on third-party packages or libraries. In simple cases (serial version with no external libraries), the code can be compiled and executed with just a C++ compiler.

Extended capabilities using externally provided software are to be included in the next, more advanced version.


OpenLSTO is available for download under the Apache V. 2.0 license. Please refer to the License page for terms and conditions.


  • Dr. Hayoung Chung
  • Dr. Xiao-Yi Zhou
  • Dr. Renato Picelli
  • Ms. Carolina Jauregui
  • Dr. Sandilya Kambampati
  • Dr. Lester Hedges
  • Dr. Zongliang Du
  • Dr. Scott Townsend

OpenLSTO-Lite (v0.1)

OpenLSTO-Lite on GitHub 

Download OpenLSTO-v0.1 as .zip

Theoretical Manual v0.1 

Tutorial v0.1

OpenLSTO (v1.0)

OpenLSTO on GitHub 

Download OpenLSTO-v1.0 as .zip

Theoretical Manual v1.0 

Tutorial v1.0 

Programmer Manual v1.0

[J1] Picelli R, Townsend S, Brampton C, Norato J, Kim HA (2017) "Stress-based shape and topology optimization with the level set method", Computer Methods in Applied Mechanics and Engineering, DOI: 10.1016/j.cma.2017.09.001
[J2] Sivapuram R, Dunning PD, Kim HA (2016) "Simultaneous material and structural optimization by multiscale topology optimization", Structural and multidisciplinary optimization, 54(5), 1267-1281, Special issue in memory of Prof George Rozvany (invited), DOI: 10.1007/s00158-016-1519-x
[J3] Dunning PD, Kim HA (2015) "Introducing the sequential linear programming level-set method for topology optimization", Structural and Multidisciplinary Optimization, 51(3), 631-643, DOI: 10.1007/s00158-014-1174-z
[J4] Dunning PD, Kim HA (2011) "Investigation and improvement of sensitivity computation using the area-fraction weighted fixed grid FEM and structural optimization", Finite Elements in Analysis and Design (invited), 47, 933-941, DOI: 10.1016/j.finel.2011.03.006

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