COMSOL Multiphysics vs OpenSim

COMSOL Multiphysics is desktop software for simulating designs, devices, and processes in engineering, manufacturing, and scientific research. It supports single-physics and fully coupled multiphysics models, including user-defined physics descriptions and equations. Model Builder covers work from geometry and CAD through physics modeling, meshing, studies, optimization, solving, and visualization. Supported fields include electromagnetics, structural mechanics, acoustics, fluid flow, heat transfer, and chemical reactions.

Model Manager provides version control, storage, search, collaboration, permissions, and support for local or remote server databases. Application Builder lets experts create custom simulation interfaces for collaborators and customers; deploying those applications requires COMSOL Server or COMSOL Compiler. Interfacing products include LiveLink for MATLAB, Simulink, and Excel, as well as CAD links or import tools. The software supports Windows, macOS, and Linux, with offline access, authoring tools, 3D visuals, and data export. It is paid, with pricing on request, and a free trial is available. Customers contact COMSOL to evaluate requirements and choose a license; a sales representative responds within one business day.

OpenSim models and simulates how humans, animals, robots, and their environment move and interact. Its graphical interface displays models and supports creating and analyzing simulations. Models can contain rigid bodies, joints, constraints, contact, muscles, and other actuators. Movement analysis tools include inverse kinematics, inverse dynamics, static optimization, and forward dynamics; Computed Muscle Control can generate muscle-driven forward simulations. The API is usable through Matlab, Python, Java, and C++, and GUI scripting uses an embedded Jython shell. Plugins can add analyses and model components, but must be built for the same OpenSim version and platform. The graphical interface is distributed for 64-bit Windows and Mac, while there is no public Linux GUI distribution; the API source can be built for Linux. OpenSim is free and open source under Apache 2.0, though models, examples, and plugins may have separate licenses. It is intended for research and teaching and welcomes academic and commercial applications. Documentation, tutorials, and a discussion forum are available. Downloading requires a SimTK account.