Design and Reliability Analysis of a Tunnel-Detection AUV Based on a Heterogeneous Dual CPU Hot Redundancy System

Abstract

A water conveyance tunnel is narrow and enclosed with a complex distribution of flow field. The performance of sensors such as Doppler log, magnetic compass, sonar, and depth gauge used by conventional underwater vehicles in the tunnel is greatly affected and can even fail. Aiming at the special operating environment and operational requirements of water conveyance tunnels, this paper designed an architecture suitable for pressurized water conveyance tunnel-detection autonomous underwater vehicles (AUVs). The tunnel-detection AUV (called AUV-T in this paper) with the architecture proposed in this paper could easily and smoothly complete inspection tasks in water conveyance tunnels, and field tests have verified the effectiveness of the architecture. Since an AUV in a water conveyance tunnel cannot go to the surface to rescue itself, in order to ensure its safety we designed the heterogeneous dual-CPU (Central Processing Unit) hot redundancy system based on dual communication lines. The reliability analysis showed that the system can significantly reduce the probability of AUV failure and ensure that the AUV can still be recovered even if it fails in the tunnel.