As the problem of global water pollution becomes increasingly serious

issues such as waste pollution and ecological maintenance in small water bodies—including coastal areas

rivers

and lakes—are gaining attention. Traditional underwater robotic arms are primarily designed for deep-sea high-precision operations

which often involve high costs

complex structures

and poor adaptability

making them unsuitable for the low-cost and highly flexible requirements of small water applications. This study proposes a modular underwater robotic arm system tailored for small water environments. Through modular architecture and standardized interface design

the system enables rapid reconfiguration and functional expansion of the robotic arm

enhancing its operational capability and reliability in turbid water conditions. The research employs theoretical analysis

simulation verification

and feasibility demonstration. It begins with clarifying design objectives through requirement analysis

followed by modular system architecture design

detailed design and theoretical calculation of key components (e.g.

standardized quick-connect interfaces)

kinematic simulation and performance evaluation using multibody dynamics software

and finally

validation of system feasibility through a detailed experimental plan. This study delivers a low-cost

highly reliable modular underwater robotic arm system

offering a practical technical solution for the widespread adoption of underwater operation equipment in small water bodies. It holds significant importance for advancing underwater robotics technology toward affordability and adaptability.