A cost-effective hardware architecture for fail-safe autonomous underwater vehicles

There has recently been a notable increase in interest in submarine robotics and more precisely in autonomous underwater vehicles (AUVs). The cost of such vehicles is generally high and therefore, safety, defined as the ability of being able to physically retrieve the AUV if an emergency situation arises, should be one of the main concerns in the design of such systems. We propose a hardware architecture, based on the field bus Controller Area Network (CAN), that specifically addresses the safety issues by using a special node which monitors the potentially hazardous situations in the underwater vehicle and reacts accordingly. The design of such node is vital and therefore internal redundancy is added to prevent a nondetected internal error from jeopardizing the safety of the system. The safety of the system is increased at a marginal cost by having the critical functions which relate to the retrieval of the AUV in a single node made of Components Off The Shelf (COTS)