RSim is a Monte Carlo simulation tool that is based on Geant4, a well-established radiation transport model. Inspired by a project that designed radiation protection for the upcoming NASA Europa mission, RSim was further developed to offer ease of use, CAD importability, and visualization capabilities. With RSim, simulations are set up and run through the user interface, eliminating the need for C++ or Geant4 input commands. Additionally, RSim is integrated with CAD and offers shape healing, making it ideal for users working with complex geometries.

RSim features a unique geometric biasing source capability to expedite simulation times while obtaining accurate statistics. Multiple shape and mesh scorers, such as energy deposition, dose, and flux calculation, can be calculated using RSim and visualized in 3D against the modeled geometries. With RSim’s intuitive interface, a rich database of materials, and multiple options for radiation source customization, engineers can easily predict radiation effects, perform shielding calculations, and assess survivability in harsh surroundings like space.