A survey of research status on the environmental adaptation technologies for marine robots

Advancement in marine robotics adaptability, which is crucial for efficient task completion in complex marine environments, is the central focus of contemporary research. This paper discusses the ongoing research and future prospects of environmentally adaptable marine robots. Initially, we provide an overview of how marine robots adapt to varying seawater pressure and buoyancy at different depths. Following this, pressure and buoyancy adaptation technologies are elaborated upon and critically analysed. The shortcomings of conventional rigid pressure resistance are addressed, along with potential solutions using pressure compensation and flexible pressure-resistance methods. Furthermore, we examine the limitations of traditional active buoyancy control and, propose improvements through passive buoyancy and an active-passive cooperative control strategy. Noteworthy advancements including active buoyancy control based on phase-change principle and fully-passive buoyancy control based on fluid compression are identified as promising areas for future development. Lastly, we outline the challenges and prospective directions for the development of adaptive technologies for marine robots, including soft-body and bionic designs, novel material applications, and innovative control methods for marine robots. This study is expected to serve as a valuable reference for future research into deep-sea marine robotic technologies.