Simulators are in important role in the Generic Intelligent Machine development. The simulator can be used to test and develop all components of the system.
The simulator in the first image is a hardware-in-the-loop (HIL) simulator, which uses the same control electronics as the real machine, but the mechanics, hydraulics and the environment is simulated. Thus, from software point-of-view the simulator is just an extra machine in the system. This allows accurate testing from communication to control with the simulator, before implementing them on the real machine.
The simulator in the second figure is a multi-robot simulator based on the Open Dynamics Engine (ODE). This simulator is simpler and is "software only" simulator, which allows flexible multiplication of it. The multi robot simulator is used in development of machine fleet functions.
The last simulator is a Matlab simulator that is used to study the interaction between the machine and the ground model.