Development of Automatic LARS for Deep-Sea AUVs Launched from and Recovered to Catamaran-Type USV

Abstract

There is a critical requirement for a LARS (Launch and Recovery System) to operate UUVs (Unmanned Underwater Vehicles) in ocean environments. Especially when UUVs are launched from and recovered by USVs (Unmanned Surface Vehicles), an automatic LARS is a very important device. This paper comprehensively presents the development of a novel launch and recovery system specifically designed for UUV operations at the bottom of USVs. The mechanical aspect of the LARS can be developed using various mechanisms; in this study, the Sarrus mechanism was applied to achieve the vertical movement required by the system. The structural analysis of the proposed the LARS has confirmed its reliability, structural integrity and operational effectiveness in ocean environments. And, a hydraulic system was applied to operate the LARS, and the overall hydraulic system was designed by calculating the capacity of each hydraulic actuator. In parallel, a complementary electrical and electronic control system was developed to operate the hydraulic systems. A testbed was built for performance testing, and LARS was installed on the testbed to perform LAB Test and Ocean Basin Test. After the performance test, the LARS was disassembled and anodised to prevent corrosion. The completed LARS was mounted on the USV. This research contributes to technologically advanced launch and recovery solution that addresses significant issues in the operation of unmanned underwater vehicles.