Performance assesment of Navigation Systems Used in Deep-Water Scientific Human-Occupied Vehicle MATSYA 6000

A precise and reliable navigation system is the key requirement for effective and safe operation of the deep-water scientific human occupied vehicles (HOV). Based on different grades of navigation sensors error models, position estimation algorithm with Monte Carlo simulation is modelled and simulated to estimate the maximum position error with Circular Error Probability (CEP 50) uncertainty limit. It is identified that the technologically-matured Inertial Navigation System integrated with Doppler Velocity Log (DVL) and acoustic ultra-short base line (USBL) positioning systems shall have relative position accuracies of 40-50m when the HOV is operating at 5500m water depths. During a 4h ascent from 5500m water depth in the Central Indian Ocean without the aid of USBL, the DVL-aided and unaided-INS, taking into account the prevailing water currents, could have a position drift with CEP50 of $3.1\pm 0.25$ km and $6.1\pm 0.25$ km, respectively. This simulation studies on estimating the position shall aid in the design of the operational philosophy of the HOV in normal and failure scenarios.