Buoyancy- and Gravity-Powered Underwater Robots

Abstract

This paper presents a new concept for driving underwater robots that is based on the interaction between the natural forces of buoyancy and gravity present in the underwater environment. Mathematical models are developed to simulate the static and dynamic characteristics of a single-link arm as in fltcenced by its design parameters and operating conditions. A computer-controlled prototype of the arm is designed, built, and tested to demonstrate the feasibility of the concept. The effect of varying the control gains, sample interval, and con trol law on the dynamic performance of the arm is presented for different payloads. The obtained results suggest the potential of this type of robot in handling objects underwater with minimal external energy.