UTSA researchers use innovative approach to find victims lost at sea | UTSA today | UTSA
Coast Guard data shows that it responded to 16,845 search and rescue operations in 2020. These operations totaled well in excess of 50,000 rescue hours. Looking for a capsized boat, a downed plane, or humans floating in the sea is often like looking for a needle in a haystack. Wind and currents can create unpredictable drifts. An object thought to be in one place may be far from its path.
“Rescuers are trying to follow the wind. They watch the speed and direction of the wind. After four hours, they’re trying to figure out where the object might be, ”Bhaganagar surmised. “But what they are seriously lacking is the drift of the samples, which occurs because of the ocean current. This is the great challenge of rescues at sea and what the Coast Guard asks us to solve. “
The UTSA team included graduate students Prasanna Kolar, Ryan beckmann, Daniel Brun, Stanford martinez and Syed mohamed. Undergraduate team members included Zachary Riddle with Finn Burmeister-Morton and Joshua Lee of the Honorary College. Together, they combined a mix of technologies to develop a new process for finding objects at sea.
One important component is light sensing and ranging technology (LIDAR), a method of remote sensing that uses light in the form of a pulsed laser to measure varying distances. To improve search and rescue, the students built a platform on a 19-foot boat where the LIDAR continuously rotates 360 degrees. They added stereoscopic depth cameras to either side of the platform. The two cameras, as well as the LIDAR, collect 100 images per second.
Sensors mounted on the boat measure the wind speed. A buoy is dropped into the water to measure the speed of waves and currents. All of this information is transmitted to a supercomputer, the size of a cell phone, to analyze the data in real time.
An algorithm predicts where a rescue object will be located. GPS is used to steer the boat in that direction where further measurements take place. Once there is a high degree of confidence that the object is in this area, the Coast Guard will send rescue boats and helicopters to search.
“We conducted a large-scale experiment dropping six-foot dummies, as well as large-scale Coast Guard dummies, into the water. We tried this in real time and got amazing results, ”Bhaganagar said.
Using an unmanned rescue vessel to locate likely search locations minimizes the risk to Coast Guard personnel, who spend fewer hours randomly searching the high seas. Boats, helicopters and highly skilled rescue operators are also expensive to deploy. Reducing their time on the water leads to more efficient operations, which saves taxpayer dollars.
Working on the Unmanned Rescue Project not only helps the Coast Guard, but also helps students gain valuable research hours while pursuing higher education. Another advantage is the experiential learning opportunities they get. This interdisciplinary project allowed them to work with colleagues from different disciplines with different expertise. To carry out the project, the team used principles of mechanical engineering, fluid dynamics and machine learning.
There were also many unique practical opportunities outside of the classroom. The students used the UTSA campus recreation pool to test prototypes and correct errors early in the process, Bhaganagar said. Once their designs were perfected, they attached the LIDAR sensor to the boat and transported it to Galveston. There, they worked alongside U.S. Coast Guard personnel to put unmanned rescue ships to the test in the Gulf of Mexico.
“Seeing an object drift in open water and understanding the signs is great value and something you can’t get in a classroom or in a textbook. It was an incredible experience, ”said Brun, who conducted field tests in Galveston. “Interacting with Coast Guard engineers was also very exciting and very valuable for the students. “
“The opportunity to support the United States Coast Guard through this project is an excellent example of collaborative research and experiential learning that we are committed to providing to our students,” added JoAnn Browning, Dean of the College of Engineering and Integrated Design at UTSA. “Working with people with different backgrounds in engineering will give our students the essential skills they need to be successful in an increasingly competitive job market. “