Gravity-gradient and magnetic-gradient inversion equations are combined to estimate the orientation and distance of an underwater object. The CKF algorithm based on EMMAF algorithm and Spherical-Radial is proposed and is applied to the fault diagnosis of slaver AUV in multi AUV collaborative positioning system. Simulation results are used to analyze the advantages and disadvantages of the three algorithms. This book looks at how a Service-Oriented Agent Architecture (SOAA) for marine robots is endowed with resilient capabilities in order to build a robust (fault-tolerant) vehicle control approach. Particular attention is paid to cognitive RCAs based on agent technologies and any other smart solution already applied or potentially applicable to UMVs. The book also presents current and future trends of RCAs for UMVs.