FreeTO vs nTop

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.

nTop is an engineering design platform for generating parametric geometry and exploring design variants. Its implicit modeling represents geometry mathematically, helping models remain stable through substantial parameter changes. Design logic can run across thousands of variants on desktop or distributed cloud compute, while GPU compute and machine learning are described as ways to shorten simulation feedback cycles. The platform supports assembly and surface modeling and imports CAD, mesh, CAE, and other formats, including STEP, Parasolid, CATIA V5, Creo, SolidWorks, STL, OBJ, Abaqus, and ANSYS; listed exports include STEP, Parasolid, STL, and 3MF. The interactive desktop application supports 64-bit Windows 11 Enterprise, Professional, and Education editions; nTop Automate also supports Red Hat Enterprise Linux 8.9. The system requirements specify at least 64 GB RAM and an NVIDIA GPU with Volta architecture or newer and 8 GB VRAM. Commercial pricing is on request. Students, educators, and academic researchers can apply for a free non-commercial education version.