Modeling and parameter estimation for in-pipe swimming robots

State-of-the-art, in-pipe, crawling robots face challenges in small diameter, non-smooth, water distribution pipes, mostly because of their direct contact with the pipe walls. On the other hand, swimming robots show greater potential in performing various maneuvers inside the pipes, because of the freedom in their motion. Such autonomous, swimming robots are needed for pipe-monitoring and leak detection in all sorts of pipe networks. Swimming motion inside confined environments is not well studied, and thus, this paper tackles the problem of modeling an in-pipe swimming vehicle. A conventional methodology that involved hydrodynamic coefficients is adopted, however the confined environment is affecting the parameters under study heavily. We discuss how these parameters rely on the pipe and robot geometry, unlike the case where the robot would swim in open-water.