Monitoring and understanding aquatic environments is critical to water sustainability. The goal of this award is to establish a theoretical framework and provide an enabling technology for robust underwater collaborative sensing with small, inexpensive robots. Inspired by the source-seeking behavior of live fish, computationally efficient algorithms are developed for cooperative tracing of the gradients of environmental fields, and their robustness is analyzed in the presence of localization error and changing communication topology. The algorithms are experimentally validated in thermal source seeking and tracing with a group of energy-efficient and highly maneuverable gliding robotic fish, which are enhanced in this project with optical communication and localization capabilities. Advanced controllers are developed for these robots to realize three-dimensional maneuvering and to track reference paths planned through collaborative sensing algorithms. This award offers fundamental understanding of limits and robustness properties of collaborative sensing by resource-limited robots, and contributes to the knowledge base in underwater communication and ranging for small robots. It enables technological advances for persistent sampling of versatile aquatic environments including coastal waters, lakes, and rivers, with a myriad of applications such as oil spill response, ecological monitoring, and port and drinking water security. The findings from this project are disseminated through publications, software sharing, and technology commercialization. The project provides interdisciplinary training opportunities for students, including those from underrepresented groups. Outreach activities, including museum/aquarium exhibits and teacher training, are developed to pique the interest of K-12 students, teachers, and the public in science and engineering.
