A snake-like robot for internal inspection of complex pipe structures (PIKo)

Abstract

Abstract-This paper presents a mechanism for navigating complex pipe structures, both horizontally and vertically. The mechanism consists of a series of identical modules interconnected by two degree of freedom active joints. A set of active wheels on each module provides propulsion. Horizontal motion is achieved through a train-like scheme, while vertical motion is achieved through spanning the pipe alternatingly with the modules. The design and the capability of horizontal and vertical motion is validated through experiments.

Modeling and path-following for a snake robot with active wheels

“…The model parameters are based on the snake robot PIKo which has been developed at the Norwegian research organization SINTEF in Trondheim, Norway [6].…”

“…FTL approaches have already been used in several designs for motion through bends [1], [6]. We therefore consider it an important benchmark against the proposed algorithm.…”

“…It utilizes a very basic principle for control: All modules should repeat the pattern of the first module -the leader -at the exact same spatial position as the leader module. This can either be done by adjusting the speed of the wheels to match the curvature shift [1], or by measuring the distance traveled by the wheels to set correct curvatures [6]. In either case slip will introduce inaccurate movements.…”

“…The model parameters used for simulation are based on the snake robot PIKo which is developed at the Norwegian research institution SINTEF in Trondheim, Norway [6]. We employ n = 6 links in the simulations and for each link i we have that −4 s. However, the head controller only calculates new joint angle and wheels velocity references every 0.025 s in order to make the simulations more similar to a control system on an actual snake robot.…”

Design of in-pipe robot based on inertial positioning and visual detection

“…In order to adapt to the particular in-pipe environment, many of the modifications have been tried. One is to add weight and equip the robot with more wheels for climbing, taking MAKRO 10 and Piko 11,12 for example. As the number of wheels increases, the degrees of freedom and the complexity of control strategies also increase.…”