Physics-Based Simulation in the CASTLE Environment.

The CASTLE simulator provides a physics-based, 3D virtual environment in which software agents can perceive, act, learn, and be evaluated. The degree of abstraction of both perceptions and actions can be varied depending on the needs of the agents. For example, visual perception can be provided to agents as rendered pixmaps or neuronal spikes, and agents can move kinematically or via force and velocity settings on motors. CASTLE can also transform both inputs and outputs to emulate biological characteristics, such as differing resolution across the visual field of view and imprecision in time or position senses. The CASTLE framework is open and can connect to software agents, graphical user interfaces, and external (possibly distributed) simulations. CASTLE is being actively developed and used with cognitive and brain models on diverse platforms, and is freely available under an open-source license.