FreeTO vs OpenMDAO

FreeTO is free, open-source MATLAB software for initializing, optimizing, and post-processing free-form 3D topology optimization problems. It accepts STL files for a design domain and load-carrying subdomains, together with mesh controls and a target volume fraction. A structured hexahedral mesh is used, and optimized structures have smooth boundaries. Inputs can define supports, force magnitudes, up to nine additional load cases, and regions that must remain unchanged. SIMP is the documented default optimization method, and SEMDOT is also supported. Topologies can be mirrored across up to three specified symmetry planes. Results include compliance, volume fraction, density arrays, element counts, optimization histories, visual topology displays, and an optional STL file. Sample problems cover a GE bracket, airplane bracket, human hand model, and quadcopter. The repository uses an MIT license and other open-source codes. Its available optimizer is optimality criteria; the MMA implementation is commented out, with code available by email request.

OpenMDAO is a free, open-source Python framework for systems analysis and multidisciplinary optimization, available for Linux and self-hosted use. It focuses on gradient-based optimization with analytic derivatives, including design spaces with hundreds or thousands of variables. Models combine components and groups, while drivers run optimization algorithms or design of experiments. Nonlinear and linear solvers can be positioned at different levels of the model hierarchy. Derivative tools include analytic partial derivatives, finite-difference and complex-step approximations, derivative checking, and forward or reverse total derivative calculations. MPI features support parallel subsystems and distributed variables across processes. Parallel computing can also support gradient-free optimization, mixed-integer nonlinear programming and design space exploration. Users can visualize models and optimization progress, and record or read model and solver cases. Dymos for transient modeling and optimal control, and pyCycle for turbine engine cycle analysis, are identified as related libraries. Installation is documented through PyPI or a cloned GitHub repository. The supported OpenMDAO 3.x line requires Python 3.10 or later; its API may change periodically during active development.