One of the more complex challenges to be overcome when modelling the dynamics of any mobile platform is the representation of the forces of friction. In this work, a verified friction model for a four-wheel planetary rover with skid steering is set out. The model is implemented in multiple simulation scenarios to cover the full scope of the rover's mobility (forward motion, turning, braking, and accelerating) in both 2D and 3D environments.

Fault tolerant design is hugely important for autonomous mobile robots such as planetary exploration rovers (PERs), as they are required to be both robust and reliable in extremely harsh environments. One of the main principles of fault tolerance is the detection and diagnosis of any faults afflicting the system. A model-based fault detection procedure is presented using forward and inverse simulation methods. The results of each method are compared for faults in different system locations to display the differences and advantages of both methods. It is shown by this comparison that the methods complement each other and can be used concurrently to diagnose output and input faults.