Evaluating autonomous system performance in the surfzone

The exploration of capability of surfzone robotics is important to improve safety and data availability at reduced cost in a dangerous environment. The US Army Engineer Research and Development Center’s Field Research Facility in Duck North Carolina, USA offers unique capability as a test center due to available resources, data, and expertise. As an example, the capability of two robotic platforms for data collection in the surfzone is evaluated. The first is the Bayonet Ocean Vehicle 350, which is a bottom crawling amphibious vehicle. A RTK mast is used for surveying the bottom position, providing a 2 cm bias with a 8.7 cm Root Mean Square Error (RMSE) over a collection period comprised of 24 separate surveys over 5 different conditions with maximum wave heights at 75 cm. Comparing to the RTK GPS derived profiles are two examples of profiles derived from a pressure sensor. The second platform is a micro Autonomous Surface vehicle that has diving capability, called a Swarm Diver. The Swarm Divers, using pressure, provides depth estimates that were compared to acoustic altimeters and traditional survey’s showing biases and RMSEs greater than 60 cm. Rapid domain mapping was also highlighted, though battery life and vehicle count limited capability.