A Preliminary Design Study of a Re-Deployable Underwater Test Bed
Dr. Nagi Khadr | Parsons Government Services, Inc.
The proposed objective is to conduct a preliminary design study on a re-deployable underwater test bed that will accommodate data collection by different sensor modalities and systems over carefully emplaced test items. Although not entirely re-deployable in the strict sense of the word, the idea is that the item emplacement aspect of the test bed makes use of special re-deployable materials that ensures a consistent predefined, yet flexible, emplacement process. In this way, by using this emplacement process at separate locations within one or more sites, comparative testing not only across modalities and systems but also across a variety of conditions may be possible.
The proposed approach to the preliminary design consists of: (1) conducting an analysis to determine item distribution scenarios that will apply to all sensor modalities and systems of interest over a variety of conditions. This step will rely on gathering and summarizing as much known item response information as possible from all modalities and systems with the cooperation of PIs of relevant projects and will include identifying the environmental ground truth measurements needed for an informed evaluation of the data collected over the different conditions; (2) fully elaborating on and investigating the feasibility of implementing a re-deployable item emplacement process that can be used for a range of different test bed scenarios. The main conceptual idea relies on deploying re-useable materials that are lightweight, can be set up on the water surface, submerged then outfitted with an adaptable mesh fabric containing a known spatial distribution of uniquely identifiable acoustic pinger tags. Using handheld tunable devices, divers can navigate from one potential emplacement spot to another on a pre-emplacement reconnaissance mission and/or a predefined item emplacement mission. The addition of an array of fixed hydrophones integrated with a GPS reference can provide geographical locations to the tags; and (3) researching site possibilities for installing test beds that will apply to the largest possible variety of conditions to all sensor modalities and systems of interest. This final step will methodically rank MR sites based on the diversity of desired test bed scenarios that can be accommodated throughout the year, also taking site accessibility and security into account.
The preliminary study is one of several undertaken in an attempt to clarify the best course of action to take when designing an underwater test site. If the proposed re-deployable item emplacement process is shown to be both feasible and cost-effective, this would pave the way towards establishing an underwater test site with test beds that are more complex than just simple grids and would rival the success that the terrestrial Standardized UXO Technology Demonstration Sites have had in evaluating and comparing emerging and existing technologies. Other benefits would come from steps (1) and (3) of the technical approach in the form of a catalog of item responses for all the relevant modalities and systems, and a ranked list of MR sites that could potentially host the desired test bed scenarios.