114 untethered UUV dives: lessons learned
The Ocean Engineering Division at the Naval Command Control and Ocean Surveillance Center RDT&E Division (NRaD) has developed and field tested two successive untethered, supervisory controlled UUV systems: a prototype, and an improved model. These robotic vehicle systems were part of the Advanced Unmanned Search System (AUSS) programme. It was only after the prototype was fielded, many lessons were learned. As a consequence of the prototype experience, the improved model was developed. The second system was a complete redesign, using state-of-the-art subsystems and technologies. The resulting product was both capable and reliable, yet flexible, creating a plethora of system evolutionary possibilities. Sea tests, improved tactics, and systems engineering became synergistic and interactive. AUSS involved pioneering research in underwater search and in UUV systems. Important knowledge was also gained in systems analysis, system engineering, and program evolution. Invaluable experience was gained from 114 successful untethered dives. The purpose of this paper is to share many of the lessons learned during the AUSS program.
Deep-Ocean Search and Inspection: Advanced Unmanned Search System (AUSS) Concept of Operation
Abstract : This report explains search tactics and many of the innovative ideas and technologies that are used to perform the AUSS deep search and inspection. These include the acoustic link, which makes untethered communications possible; the Doppler sonar, which enables it to track its position and navigate without interfering with the acoustic link; high-quality sonars and optical sensors; supervisory control and sophisticated computers and software.
Contractor Failure: Analysis
The possibility exists for any construction contractor to fail to filfill the contract requirements associated with a facility. Contractor failure occurs when a contractor is unable to perform his/her contractual duties, thus requiring the facility owner to invoke the contract's nonperformance clause. This paper provides aggregate contractor business failure statistics and outlines potential causes for failure. A framework to identify and quantify the associated costs is also introduced. Several case studies are presented to examine the cause and cost of failure and the means by which the facilities were completed. Alternatives available for project completion when contractor failure occurs are discussed. Recommendations to identify and monitor contractors at high risk for failure are outlined as well. This paper provides facility owners with a greater awareness of the possibility of contractor failure, how to quantify costs of contractor failure, and avoidance techniques.