The Maritime Security Laboratory (MSL) provides an experimental laboratory for the verification of new theoretical results, technologies, and algorithms. The uniqueness of the Laboratory is that MSL experiments are performed directly in the Hudson River Estuary itself. Therefore, new results are verified in the real environment in which they will have to perform, complete with all the complexity that a shallow tidal estuary brings. This complexity is due to variability of the current, salinity, temperature, winds, turbidity, as well as human-made factors including ambient noise due to surface and air traffic, construction noise, and various forms of electromagnetic radiation. All of these must be accounted for in parsing above and below surface threats, and therefore must be included in an effective laboratory environment.
MSL has instrumentation deployed throughout the estuary to collect weather and environmental data, and through modeling, to predict their characteristics. For the actual MSL execution of experiments, two sites are frequently utilized based on their scientific characteristics and their accessibility – both physically and by radio communications, and by safety considerations. The test sites are shown in Fig. 1.
Figure 1: The MSL Test Sites
MSL utilizes two research vessels in its experiments, as shown in Fig. 2. The larger boat is the RV Savitsky. It is specially constructed and fitted out for maritime research purposes. Towards the stern is an A-frame for loading large and heavy items onto and off of the boat. Radio antennas are affixed to the mast and enable communication of experimental data back to scientists on campus, in real time.
The smaller boat, the Phoenix, is a support boat. It is used to deploy sensors while they are cabled to the Savitsky. It is also used to deploy remote instrumentation, deploy swimmers, and provide for safety. A third smaller zodiac inflatable boat is used predominantly to deploy underwater vehicles.
On the boat, the sensor cables are terminated on a special purpose-built high powered, shock-mounted computer. The Data Acquisition Board on the computer is capable of terminating eight hydrophones, although the computer is capable of accommodating more.
Communications with the boat is currently accomplished with an IEEE 802.11 (WiFi) radio link. This link is used to enable real-time data to be transmitted to the Visualization and Analysis Center (VAC). This allows experiments to be controlled from the VAC, in terms of when and how long data is recorded. Perhaps most importantly, it provides Data Quality Assurance, to assure that at the end of the day, good data has been collected. Another important application of the radio link is to maintain real-time communication with the boat crew during experiments. This is accomplished by establishing a chat line with the boat, and is critical to the logistics and administration of experiments. The radio link is connected to the VAC over the campus network.
Figure 2: Stevens’ Research Vessels. The larger boat is the RV Savitsky, and the smaller is the Phoenix. A buoy supporting a suspended hydrophone can be seen off the port bow of the Phoenix
The Visualization and Analysis Center has several major purposes:
- To provide the capability to administer and control experiments, whether on the boat, or elsewhere
- To ensure data quality assurance during experiments
- To enable the ability to reconfigure experiments in response to the data received.
- To provide an environment for research, algorithm development, and laboratory infrastructure improvements
- To provide a demonstration capability for key stakeholders and potential customers and users
- The VAC contains both Linux and Windows computing environments.
In addition to real-time data feeds into the VAC, six video cameras have been deployed to provide real-time visual observation of experiments, as well as providing a video data source to automatically collect data analyzing surface traffic and low flying aircraft traffic. The VAC is shown in Fig. 3.
Figure 3: The MSL Visualization and Analysis Center
Before experiments are conducted in the Estuary, MSL frequently tests equipment in the Davidson lab tow tank.
Figure 4: A diver in the tow tank